from flask import (
    Flask,
    request,
    jsonify,
    send_from_directory,
    Response,
)
from flask_cors import CORS
import json
import time
from datetime import datetime
import os
import sys
from core import PLCDataStreamer
from utils.json_manager import JSONManager, SchemaManager

app = Flask(__name__)
CORS(
    app,
    resources={
        r"/api/*": {
            "origins": [
                "http://localhost:5173/app",
                "http://127.0.0.1:5173/app",
                "*",
            ]
        }
    },
)
app.secret_key = "plc_streamer_secret_key"

# React build directory (for Vite production build)
REACT_DIST_DIR = os.path.join(os.path.abspath("."), "frontend", "dist")


def resource_path(relative_path):
    """Get absolute path to resource, works for dev and for PyInstaller"""
    try:
        # PyInstaller creates a temp folder and stores path in _MEIPASS
        base_path = sys._MEIPASS
    except Exception:
        # Not running in a bundle
        base_path = os.path.abspath(".")

    return os.path.join(base_path, relative_path)


def project_path(*parts: str) -> str:
    """Build absolute path from the project root (based on this file)."""
    base_dir = os.path.abspath(os.path.dirname(__file__))
    return os.path.join(base_dir, *parts)


# Global instances
streamer = None
json_manager = JSONManager()
schema_manager = SchemaManager()


def check_streamer_initialized():
    """Check if streamer is initialized, return error response if not"""
    if streamer is None:
        return jsonify({"error": "Application not initialized"}), 503
    return None


@app.route("/images/<filename>")
def serve_image(filename):
    """Serve images from .images directory"""
    return send_from_directory(".images", filename)


@app.route("/static/<path:filename>")
def serve_static(filename):
    """Serve static files (CSS, JS, etc.)"""
    return send_from_directory("static", filename)


@app.route("/favicon.ico")
def serve_favicon():
    """Serve application favicon from robust locations.

    Priority:
      1) frontend/public/favicon.ico
      2) frontend/public/record.png
      3) static/icons/record.png
    """
    # Use absolute paths for reliability (works in dev and bundled)
    public_dir = project_path("frontend", "public")
    public_favicon = os.path.join(public_dir, "favicon.ico")
    public_record = os.path.join(public_dir, "record.png")

    if os.path.exists(public_favicon):
        return send_from_directory(public_dir, "favicon.ico")
    if os.path.exists(public_record):
        return send_from_directory(public_dir, "record.png")

    # Fallback: static/icons
    static_icons_dir = project_path("static", "icons")
    if os.path.exists(os.path.join(static_icons_dir, "record.png")):
        return send_from_directory(static_icons_dir, "record.png")

    # Final fallback: 404
    return Response("Favicon not found", status=404, mimetype="text/plain")


@app.route("/record.png")
def serve_public_record_png():
    """Serve /record.png from the React public folder with fallbacks."""
    public_dir = project_path("frontend", "public")
    public_record = os.path.join(public_dir, "record.png")

    if os.path.exists(public_record):
        return send_from_directory(public_dir, "record.png")

    static_icons_dir = project_path("static", "icons")
    if os.path.exists(os.path.join(static_icons_dir, "record.png")):
        return send_from_directory(static_icons_dir, "record.png")

    return Response("record.png not found", status=404, mimetype="text/plain")


# ==============================
# Frontend (React SPA)
# ==============================


@app.route("/assets/<path:filename>")
def serve_react_assets(filename):
    """Serve built React assets from Vite (production)."""
    assets_dir = os.path.join(REACT_DIST_DIR, "assets")
    return send_from_directory(assets_dir, filename)


@app.route("/")
@app.route("/app")
@app.route("/app/<path:path>")
def serve_react_index(path: str = ""):
    """Serve React SPA index (expects Vite build at frontend/dist)."""
    index_path = os.path.join(REACT_DIST_DIR, "index.html")
    if not os.path.exists(index_path):
        return Response(
            "React build not found. Run 'cd frontend && npm install && npm run build' first.",
            status=500,
            mimetype="text/plain",
        )
    return send_from_directory(REACT_DIST_DIR, "index.html")


## Legacy UI removed after migration to React


# ==============================
# Unified JSON Configuration API
# ==============================


@app.route("/api/config/schemas", methods=["GET"])
def list_config_schemas():
    """List all available configuration schemas."""
    try:
        schemas = schema_manager.list_available_schemas()
        return jsonify({"success": True, "schemas": schemas})
    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/config/schema/<schema_id>", methods=["GET"])
def get_config_schema(schema_id):
    """Get a specific JSON schema with optional UI schema."""
    try:
        # Get main schema
        schema = schema_manager.get_schema(schema_id)
        if not schema:
            return (
                jsonify({"success": False, "error": f"Schema '{schema_id}' not found"}),
                404,
            )

        # Get optional UI schema
        ui_schema = schema_manager.get_ui_schema(schema_id)

        response = {"success": True, "schema": schema}
        if ui_schema:
            response["ui_schema"] = ui_schema

        return jsonify(response)

    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/config/<config_id>", methods=["GET"])
def read_config(config_id):
    """Read configuration data from JSON file."""
    try:
        data = json_manager.read_json(config_id)
        return jsonify({"success": True, "data": data})
    except ValueError as e:
        return jsonify({"success": False, "error": str(e)}), 400
    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/config/<config_id>", methods=["PUT"])
def write_config(config_id):
    """Write configuration data to JSON file."""
    try:
        payload = request.get_json(force=True, silent=False)
        if not payload:
            return jsonify({"success": False, "error": "No JSON data provided"}), 400

        # Write the data
        json_manager.write_json(config_id, payload)

        # Notify backend to reload if it's PLC config
        if config_id == "plc" and streamer:
            try:
                streamer.config_manager.load_configuration()
            except Exception as e:
                # Log the error but don't fail the save operation
                print(f"Warning: Could not reload config in backend: {e}")

        return jsonify(
            {
                "success": True,
                "message": f"Configuration '{config_id}' saved successfully",
            }
        )

    except ValueError as e:
        return jsonify({"success": False, "error": str(e)}), 400
    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/config/<config_id>/export", methods=["GET"])
def export_config(config_id):
    """Export configuration as downloadable JSON file."""
    try:
        data = json_manager.read_json(config_id)

        # Prepare download response
        content = json.dumps(data, indent=2, ensure_ascii=False)
        filename = f"{config_id}_export_{datetime.now().strftime('%Y%m%d_%H%M%S')}.json"

        response = Response(content, mimetype="application/json")
        response.headers["Content-Disposition"] = f"attachment; filename={filename}"
        return response

    except ValueError as e:
        return jsonify({"success": False, "error": str(e)}), 400
    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/config/<config_id>/reload", methods=["POST"])
def reload_config(config_id):
    """Notify backend to reload configuration from JSON files."""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        if config_id == "plc":
            streamer.config_manager.load_configuration()
        elif config_id in ["dataset-definitions", "dataset-variables"]:
            # Reload dataset configuration
            streamer.load_datasets()
        elif config_id in ["plot-definitions", "plot-variables"]:
            # Reload plot configuration if needed
            pass

        return jsonify(
            {
                "success": True,
                "message": f"Configuration '{config_id}' reloaded successfully",
            }
        )

    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


# ==============================
# Operational API (PLC Control, Streaming, etc.)
# ==============================


@app.route("/api/plc/config", methods=["POST"])
def update_plc_config():
    """Update PLC configuration"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()
        ip = data.get("ip", "10.1.33.11")
        rack = int(data.get("rack", 0))
        slot = int(data.get("slot", 2))

        streamer.update_plc_config(ip, rack, slot)
        return jsonify({"success": True, "message": "PLC configuration updated"})

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 400


@app.route("/api/udp/config", methods=["POST"])
def update_udp_config():
    """Update UDP configuration"""
    try:
        data = request.get_json()
        host = data.get("host", "127.0.0.1")
        port = int(data.get("port", 9870))
        sampling_interval = data.get("sampling_interval")  # Optional, can be None

        streamer.update_udp_config(host, port, sampling_interval)
        return jsonify({"success": True, "message": "UDP configuration updated"})

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 400


@app.route("/api/csv/config", methods=["GET"])
def get_csv_config():
    """Get CSV recording configuration"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        csv_config = streamer.config_manager.csv_config.copy()

        # Add current directory information
        current_dir = streamer.config_manager.get_csv_directory_path()
        csv_config["current_directory"] = os.path.abspath(current_dir)
        csv_config["directory_exists"] = os.path.exists(current_dir)

        # Add disk space info
        disk_info = streamer.get_disk_space_info()
        if disk_info:
            csv_config["disk_space"] = disk_info

        return jsonify({"success": True, "config": csv_config})

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 500


@app.route("/api/csv/config", methods=["POST"])
def update_csv_config():
    """Update CSV recording configuration"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()

        # Extract valid configuration parameters
        config_updates = {}
        valid_params = {
            "records_directory",
            "rotation_enabled",
            "max_size_mb",
            "max_days",
            "max_hours",
            "cleanup_interval_hours",
        }

        for param in valid_params:
            if param in data:
                config_updates[param] = data[param]

        if not config_updates:
            return (
                jsonify(
                    {
                        "success": False,
                        "message": "No valid configuration parameters provided",
                    }
                ),
                400,
            )

        # Update configuration
        result = streamer.config_manager.update_csv_config(**config_updates)

        return jsonify(
            {
                "success": True,
                "message": "CSV configuration updated successfully",
                "old_config": result["old_config"],
                "new_config": result["new_config"],
            }
        )

    except ValueError as e:
        return jsonify({"success": False, "message": str(e)}), 400
    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 500


@app.route("/api/csv/cleanup", methods=["POST"])
def trigger_csv_cleanup():
    """Manually trigger CSV cleanup"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        # Perform cleanup
        streamer.streamer.perform_csv_cleanup()
        return jsonify(
            {"success": True, "message": "CSV cleanup completed successfully"}
        )

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 500


@app.route("/api/csv/directory/info", methods=["GET"])
def get_csv_directory_info():
    """Get information about CSV directory and files"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        base_dir = streamer.config_manager.get_csv_directory_path()

        info = {
            "base_directory": os.path.abspath(base_dir),
            "directory_exists": os.path.exists(base_dir),
            "total_files": 0,
            "total_size_mb": 0,
            "oldest_file": None,
            "newest_file": None,
            "day_folders": [],
        }

        if os.path.exists(base_dir):
            total_size = 0
            oldest_time = None
            newest_time = None

            for day_folder in os.listdir(base_dir):
                day_path = os.path.join(base_dir, day_folder)
                if os.path.isdir(day_path):
                    day_info = {"name": day_folder, "files": 0, "size_mb": 0}

                    for file_name in os.listdir(day_path):
                        if file_name.endswith(".csv"):
                            file_path = os.path.join(day_path, file_name)
                            if os.path.isfile(file_path):
                                stat = os.stat(file_path)
                                file_size = stat.st_size
                                file_time = stat.st_mtime

                                info["total_files"] += 1
                                day_info["files"] += 1
                                total_size += file_size
                                day_info["size_mb"] += file_size / (1024 * 1024)

                                if oldest_time is None or file_time < oldest_time:
                                    oldest_time = file_time
                                    info["oldest_file"] = datetime.fromtimestamp(
                                        file_time
                                    ).isoformat()

                                if newest_time is None or file_time > newest_time:
                                    newest_time = file_time
                                    info["newest_file"] = datetime.fromtimestamp(
                                        file_time
                                    ).isoformat()

                    day_info["size_mb"] = round(day_info["size_mb"], 2)
                    info["day_folders"].append(day_info)

            info["total_size_mb"] = round(total_size / (1024 * 1024), 2)
            info["day_folders"].sort(key=lambda x: x["name"], reverse=True)

        return jsonify({"success": True, "info": info})

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 500


@app.route("/api/plc/connect", methods=["POST"])
def connect_plc():
    """Connect to PLC"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    if streamer.connect_plc():
        return jsonify({"success": True, "message": "Connected to PLC"})
    else:
        # Extraer detalle de error si disponible
        last_error = None
        try:
            last_error = streamer.plc_client.last_error
        except Exception:
            last_error = None
        return (
            jsonify(
                {
                    "success": False,
                    "message": "Error connecting to PLC",
                    "error": last_error,
                    "plc_config": streamer.config_manager.plc_config,
                }
            ),
            500,
        )


@app.route("/api/plc/disconnect", methods=["POST"])
def disconnect_plc():
    """Disconnect from PLC"""
    streamer.disconnect_plc()
    return jsonify({"success": True, "message": "Disconnected from PLC"})


@app.route("/api/variables", methods=["POST"])
def add_variable():
    """Add a new variable"""
    try:
        data = request.get_json()
        name = data.get("name")
        area = data.get("area")
        db = int(data.get("db"))
        offset = int(data.get("offset"))
        var_type = data.get("type")
        bit = data.get("bit")  # Added bit parameter

        valid_types = [
            "real",
            "int",
            "bool",
            "dint",
            "word",
            "byte",
            "uint",
            "udint",
            "sint",
            "usint",
        ]
        valid_areas = ["db", "mw", "m", "pew", "pe", "paw", "pa", "e", "a", "mb"]

        if (
            not name
            or not area
            or var_type not in valid_types
            or area.lower() not in valid_areas
        ):
            return jsonify({"success": False, "message": "Invalid data"}), 400

        if area.lower() in ["e", "a", "mb"] and bit is None:
            return (
                jsonify(
                    {
                        "success": False,
                        "message": "Bit position must be specified for bit areas",
                    }
                ),
                400,
            )

        if area.lower() in ["e", "a", "mb"] and (bit < 0 or bit > 7):
            return (
                jsonify(
                    {
                        "success": False,
                        "message": "Bit position must be between 0 and 7",
                    }
                ),
                400,
            )

        streamer.add_variable(name, area, db, offset, var_type, bit)
        return jsonify({"success": True, "message": f"Variable {name} added"})

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 400


@app.route("/api/variables/<name>", methods=["DELETE"])
def remove_variable(name):
    """Remove a variable"""
    streamer.remove_variable(name)
    return jsonify({"success": True, "message": f"Variable {name} removed"})


@app.route("/api/variables/<name>", methods=["GET"])
def get_variable(name):
    """Get a specific variable configuration from current dataset"""
    try:
        if not streamer.current_dataset_id:
            return (
                jsonify({"success": False, "message": "No dataset selected"}),
                400,
            )

        current_variables = streamer.get_dataset_variables(streamer.current_dataset_id)
        if name not in current_variables:
            return (
                jsonify({"success": False, "message": f"Variable {name} not found"}),
                404,
            )

        var_config = current_variables[name].copy()
        var_config["name"] = name

        # Check if variable is in streaming list for current dataset
        streaming_vars = streamer.datasets[streamer.current_dataset_id].get(
            "streaming_variables", []
        )
        var_config["streaming"] = name in streaming_vars

        return jsonify({"success": True, "variable": var_config})

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 400


@app.route("/api/variables/<name>", methods=["PUT"])
def update_variable(name):
    """Update an existing variable in current dataset"""
    try:
        if not streamer.current_dataset_id:
            return jsonify({"success": False, "message": "No dataset selected"}), 400

        data = request.get_json()
        new_name = data.get("name", name)
        area = data.get("area")
        db = int(data.get("db", 1))
        offset = int(data.get("offset"))
        var_type = data.get("type")
        bit = data.get("bit")

        valid_types = [
            "real",
            "int",
            "bool",
            "dint",
            "word",
            "byte",
            "uint",
            "udint",
            "sint",
            "usint",
        ]
        valid_areas = ["db", "mw", "m", "pew", "pe", "paw", "pa", "e", "a", "mb"]

        if (
            not new_name
            or not area
            or var_type not in valid_types
            or area.lower() not in valid_areas
        ):
            return jsonify({"success": False, "message": "Invalid data"}), 400

        if area.lower() in ["e", "a", "mb"] and bit is None:
            return (
                jsonify(
                    {
                        "success": False,
                        "message": "Bit position must be specified for bit areas",
                    }
                ),
                400,
            )

        if area.lower() in ["e", "a", "mb"] and (bit < 0 or bit > 7):
            return (
                jsonify(
                    {
                        "success": False,
                        "message": "Bit position must be between 0 and 7",
                    }
                ),
                400,
            )

        current_dataset_id = streamer.current_dataset_id
        current_variables = streamer.get_dataset_variables(current_dataset_id)

        # Check if variable exists in current dataset
        if name not in current_variables:
            return (
                jsonify({"success": False, "message": f"Variable {name} not found"}),
                404,
            )

        # Check if new name already exists (if name is changing)
        if name != new_name and new_name in current_variables:
            return (
                jsonify(
                    {
                        "success": False,
                        "message": f"Variable {new_name} already exists",
                    }
                ),
                400,
            )

        # Preserve streaming state
        streaming_vars = streamer.datasets[current_dataset_id].get(
            "streaming_variables", []
        )
        was_streaming = name in streaming_vars

        # Remove old variable
        streamer.remove_variable_from_dataset(current_dataset_id, name)

        # Add updated variable
        streamer.add_variable_to_dataset(
            current_dataset_id, new_name, area, db, offset, var_type, bit, was_streaming
        )

        return jsonify({"success": True, "message": "Variable updated successfully"})

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 400


@app.route("/api/variables/<name>/streaming", methods=["POST"])
def toggle_variable_streaming(name):
    """Toggle streaming for a specific variable in current dataset"""
    try:
        if not streamer.current_dataset_id:
            return jsonify({"success": False, "message": "No dataset selected"}), 400

        data = request.get_json()
        enabled = data.get("enabled", False)

        # Use the new dataset-specific method
        streamer.toggle_variable_streaming(streamer.current_dataset_id, name, enabled)

        status = "enabled" if enabled else "disabled"
        return jsonify(
            {"success": True, "message": f"Variable {name} streaming {status}"}
        )

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 400


@app.route("/api/variables/streaming", methods=["GET"])
def get_streaming_variables():
    """Get list of variables enabled for streaming in current dataset"""
    if streamer is None:
        return jsonify({"success": False, "error": "Streamer not initialized"}), 503

    # Get streaming variables from current dataset
    streaming_vars = []
    if streamer.current_dataset_id and streamer.current_dataset_id in streamer.datasets:
        streaming_vars = streamer.datasets[streamer.current_dataset_id].get(
            "streaming_variables", []
        )

    return jsonify({"success": True, "streaming_variables": streaming_vars})


@app.route("/api/datasets/<dataset_id>/variables/values", methods=["GET"])
def get_dataset_variable_values(dataset_id):
    """Get current values of all variables in a dataset - CACHE ONLY"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        # Check if dataset exists
        if dataset_id not in streamer.datasets:
            return (
                jsonify(
                    {"success": False, "message": f"Dataset '{dataset_id}' not found"}
                ),
                404,
            )

        # Get dataset variables
        dataset_variables = streamer.get_dataset_variables(dataset_id)

        if not dataset_variables:
            return jsonify(
                {
                    "success": True,
                    "message": "No variables defined in this dataset",
                    "values": {},
                    "source": "no_variables",
                }
            )

        # Check if dataset is active (required for cache to be populated)
        if dataset_id not in streamer.active_datasets:
            return jsonify(
                {
                    "success": False,
                    "message": f"Dataset '{dataset_id}' is not active. Activate the dataset to start reading variables and populate cache.",
                    "error_type": "dataset_inactive",
                    "values": {},
                    "detailed_errors": {},
                    "stats": {
                        "success": 0,
                        "failed": 0,
                        "total": len(dataset_variables),
                    },
                    "timestamp": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
                    "source": "no_cache_dataset_inactive",
                    "is_cached": False,
                }
            )

        # Check if PLC is connected (required for streaming to populate cache)
        if not streamer.plc_client.is_connected():
            return jsonify(
                {
                    "success": False,
                    "message": "PLC not connected. Connect to PLC and activate dataset to populate cache.",
                    "error_type": "plc_disconnected",
                    "values": {},
                    "detailed_errors": {},
                    "stats": {
                        "success": 0,
                        "failed": 0,
                        "total": len(dataset_variables),
                    },
                    "timestamp": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
                    "source": "no_cache_plc_disconnected",
                    "is_cached": False,
                }
            )

        # Get cached values - this is the ONLY source of data according to application principles
        if not streamer.has_cached_values(dataset_id):
            return jsonify(
                {
                    "success": False,
                    "message": f"No cached values available for dataset '{dataset_id}'. Cache is populated by the streaming process at the dataset's configured interval. Please wait for the next reading cycle.",
                    "error_type": "no_cache_available",
                    "values": {},
                    "detailed_errors": {},
                    "stats": {
                        "success": 0,
                        "failed": 0,
                        "total": len(dataset_variables),
                    },
                    "timestamp": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
                    "source": "no_cache_available",
                    "is_cached": False,
                    "note": f"Dataset reads every {streamer.config_manager.get_dataset_sampling_interval(dataset_id)}s",
                }
            )

        # Get cached values (the ONLY valid source according to application design)
        read_result = streamer.get_cached_dataset_values(dataset_id)

        # Convert timestamp from ISO format to readable format for consistency
        if read_result.get("timestamp"):
            try:
                cached_timestamp = datetime.fromisoformat(read_result["timestamp"])
                read_result["timestamp"] = cached_timestamp.strftime(
                    "%Y-%m-%d %H:%M:%S"
                )
            except:
                pass  # Keep original timestamp if conversion fails

        # Extract values and handle diagnostics
        if not read_result.get("success", False):
            # Complete failure case
            error_msg = read_result.get("error", "Unknown error reading variables")
            error_type = read_result.get("error_type", "unknown")

            # Log detailed error information
            if streamer.logger:
                streamer.logger.error(
                    f"Cached values indicate failure for dataset '{dataset_id}': {error_msg}"
                )
                if read_result.get("errors"):
                    for var_name, var_error in read_result["errors"].items():
                        streamer.logger.error(f"  Variable '{var_name}': {var_error}")

            return (
                jsonify(
                    {
                        "success": False,
                        "message": error_msg,
                        "error_type": error_type,
                        "values": {},
                        "detailed_errors": read_result.get("errors", {}),
                        "stats": read_result.get("stats", {}),
                        "timestamp": read_result.get(
                            "timestamp", datetime.now().strftime("%Y-%m-%d %H:%M:%S")
                        ),
                        "source": "cache",
                        "is_cached": True,
                    }
                ),
                500,
            )

        # Success or partial success case
        raw_values = read_result.get("values", {})
        variable_errors = read_result.get("errors", {})
        stats = read_result.get("stats", {})

        # Format values for display
        formatted_values = {}
        error_details = {}

        for var_name, value in raw_values.items():
            if value is not None:
                var_config = dataset_variables[var_name]
                var_type = var_config.get("type", "unknown")

                # Format value based on type
                try:
                    if var_type == "real":
                        formatted_values[var_name] = (
                            f"{value:.3f}"
                            if isinstance(value, (int, float))
                            else str(value)
                        )
                    elif var_type == "bool":
                        formatted_values[var_name] = "TRUE" if value else "FALSE"
                    elif var_type in [
                        "int",
                        "uint",
                        "dint",
                        "udint",
                        "word",
                        "byte",
                        "sint",
                        "usint",
                    ]:
                        formatted_values[var_name] = (
                            str(int(value))
                            if isinstance(value, (int, float))
                            else str(value)
                        )
                    else:
                        formatted_values[var_name] = str(value)
                except Exception as format_error:
                    formatted_values[var_name] = "FORMAT_ERROR"
                    error_details[var_name] = f"Format error: {str(format_error)}"
            else:
                # Variable had an error - get the specific error message
                specific_error = variable_errors.get(var_name, "Unknown error")
                formatted_values[var_name] = "ERROR"
                error_details[var_name] = specific_error

        # Prepare response message
        total_vars = stats.get("total", len(dataset_variables))
        success_vars = stats.get("success", 0)
        failed_vars = stats.get("failed", 0)

        # Determine data source for message (always cache now)
        data_source = "cache"
        source_text = " (from streaming cache)"

        if failed_vars == 0:
            message = (
                f"Successfully displaying all {success_vars} variables{source_text}"
            )
            response_success = True
        else:
            message = f"Partial data available: {success_vars}/{total_vars} variables have valid cached values, {failed_vars} failed{source_text}"
            response_success = True  # Still success if we got some values

            # Log warnings for partial failures
            if streamer.logger:
                streamer.logger.warning(
                    f"Partial failure in cached values for dataset '{dataset_id}': {message}"
                )
                for var_name, var_error in error_details.items():
                    if formatted_values.get(var_name) == "ERROR":
                        streamer.logger.warning(f"  Variable '{var_name}': {var_error}")

        return jsonify(
            {
                "success": response_success,
                "message": message,
                "values": formatted_values,
                "detailed_errors": error_details,
                "stats": stats,
                "timestamp": read_result.get(
                    "timestamp", datetime.now().strftime("%Y-%m-%d %H:%M:%S")
                ),
                "warning": read_result.get("warning"),
                "source": data_source,
                "is_cached": True,
                "cache_info": f"Dataset reads every {streamer.config_manager.get_dataset_sampling_interval(dataset_id)}s",
            }
        )

    except Exception as e:
        return (
            jsonify(
                {
                    "success": False,
                    "message": f"Error retrieving cached variable values: {str(e)}",
                    "values": {},
                }
            ),
            500,
        )


# Dataset Management API Endpoints


@app.route("/api/datasets", methods=["GET"])
def get_datasets():
    """Get all datasets"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    return jsonify(
        {
            "success": True,
            "datasets": streamer.datasets,
            "active_datasets": list(streamer.active_datasets),
            "current_dataset_id": streamer.current_dataset_id,
        }
    )


@app.route("/api/datasets", methods=["POST"])
def create_dataset():
    """Create a new dataset"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()
        dataset_id = data.get("dataset_id", "").strip()
        name = data.get("name", "").strip()
        prefix = data.get("prefix", "").strip()
        sampling_interval = data.get("sampling_interval")

        if not dataset_id or not name or not prefix:
            return (
                jsonify(
                    {
                        "success": False,
                        "message": "Dataset ID, name, and prefix are required",
                    }
                ),
                400,
            )

        # Validate sampling interval if provided
        if sampling_interval is not None:
            sampling_interval = float(sampling_interval)
            if sampling_interval < 0.01:
                return (
                    jsonify(
                        {
                            "success": False,
                            "message": "Sampling interval must be at least 0.01 seconds",
                        }
                    ),
                    400,
                )

        streamer.create_dataset(dataset_id, name, prefix, sampling_interval)

        return jsonify(
            {
                "success": True,
                "message": f"Dataset '{name}' created successfully",
                "dataset_id": dataset_id,
            }
        )

    except ValueError as e:
        return jsonify({"success": False, "message": str(e)}), 400
    except Exception as e:
        return (
            jsonify({"success": False, "message": f"Error creating dataset: {str(e)}"}),
            500,
        )


@app.route("/api/datasets/<dataset_id>", methods=["DELETE"])
def delete_dataset(dataset_id):
    """Delete a dataset"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        streamer.delete_dataset(dataset_id)
        return jsonify({"success": True, "message": "Dataset deleted successfully"})
    except ValueError as e:
        return jsonify({"success": False, "message": str(e)}), 404
    except Exception as e:
        return (
            jsonify({"success": False, "message": f"Error deleting dataset: {str(e)}"}),
            500,
        )


@app.route("/api/datasets/<dataset_id>/activate", methods=["POST"])
def activate_dataset(dataset_id):
    """Activate a dataset for streaming"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        streamer.activate_dataset(dataset_id)
        return jsonify({"success": True, "message": "Dataset activated successfully"})
    except ValueError as e:
        return jsonify({"success": False, "message": str(e)}), 404
    except RuntimeError as e:
        return jsonify({"success": False, "message": str(e)}), 400
    except Exception as e:
        return (
            jsonify(
                {"success": False, "message": f"Error activating dataset: {str(e)}"}
            ),
            500,
        )


@app.route("/api/datasets/<dataset_id>/deactivate", methods=["POST"])
def deactivate_dataset(dataset_id):
    """Deactivate a dataset"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        streamer.deactivate_dataset(dataset_id)
        return jsonify({"success": True, "message": "Dataset deactivated successfully"})
    except ValueError as e:
        return jsonify({"success": False, "message": str(e)}), 404
    except Exception as e:
        return (
            jsonify(
                {"success": False, "message": f"Error deactivating dataset: {str(e)}"}
            ),
            500,
        )


@app.route("/api/datasets/<dataset_id>/variables", methods=["POST"])
def add_variable_to_dataset(dataset_id):
    """Add a variable to a dataset"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()
        name = data.get("name", "").strip()
        area = data.get("area", "").strip()
        db = data.get("db", 1)
        offset = data.get("offset", 0)
        var_type = data.get("type", "").strip()
        bit = data.get("bit")
        streaming = data.get("streaming", False)

        if not name or not area or not var_type:
            return (
                jsonify(
                    {
                        "success": False,
                        "message": "Variable name, area, and type are required",
                    }
                ),
                400,
            )

        streamer.add_variable_to_dataset(
            dataset_id, name, area, db, offset, var_type, bit, streaming
        )

        return jsonify(
            {
                "success": True,
                "message": f"Variable '{name}' added to dataset successfully",
            }
        )

    except ValueError as e:
        return jsonify({"success": False, "message": str(e)}), 400
    except Exception as e:
        return (
            jsonify({"success": False, "message": f"Error adding variable: {str(e)}"}),
            500,
        )


@app.route("/api/datasets/<dataset_id>/variables/<variable_name>", methods=["DELETE"])
def remove_variable_from_dataset(dataset_id, variable_name):
    """Remove a variable from a dataset"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        streamer.remove_variable_from_dataset(dataset_id, variable_name)
        return jsonify(
            {
                "success": True,
                "message": f"Variable '{variable_name}' removed from dataset successfully",
            }
        )
    except ValueError as e:
        return jsonify({"success": False, "message": str(e)}), 404
    except Exception as e:
        return (
            jsonify(
                {"success": False, "message": f"Error removing variable: {str(e)}"}
            ),
            500,
        )


@app.route(
    "/api/datasets/<dataset_id>/variables/<variable_name>/streaming", methods=["POST"]
)
def toggle_variable_streaming_in_dataset(dataset_id, variable_name):
    """Toggle streaming for a variable in a dataset"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()
        enabled = data.get("enabled", False)

        streamer.toggle_variable_streaming(dataset_id, variable_name, enabled)

        return jsonify(
            {
                "success": True,
                "message": f"Variable '{variable_name}' streaming {'enabled' if enabled else 'disabled'}",
            }
        )
    except ValueError as e:
        return jsonify({"success": False, "message": str(e)}), 404
    except Exception as e:
        return (
            jsonify(
                {"success": False, "message": f"Error toggling streaming: {str(e)}"}
            ),
            500,
        )


@app.route("/api/datasets/current", methods=["POST"])
def set_current_dataset():
    """Set the current dataset for editing"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()
        dataset_id = data.get("dataset_id")

        if dataset_id and dataset_id in streamer.datasets:
            streamer.current_dataset_id = dataset_id
            # Note: No need to save - this is just changing current selection in memory
            return jsonify(
                {
                    "success": True,
                    "message": "Current dataset updated successfully",
                    "current_dataset_id": dataset_id,
                }
            )
        else:
            return jsonify({"success": False, "message": "Invalid dataset ID"}), 400

    except Exception as e:
        return (
            jsonify(
                {
                    "success": False,
                    "message": f"Error setting current dataset: {str(e)}",
                }
            ),
            500,
        )


@app.route("/api/streaming/start", methods=["POST"])
def start_streaming():
    """Start UDP streaming (legacy endpoint - now only starts UDP streaming)"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    if streamer.start_streaming():
        return jsonify({"success": True, "message": "UDP streaming started"})
    else:
        return (
            jsonify({"success": False, "message": "Error starting UDP streaming"}),
            500,
        )


@app.route("/api/streaming/stop", methods=["POST"])
def stop_streaming():
    """Stop UDP streaming (legacy endpoint - now only stops UDP streaming)"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    streamer.stop_streaming()
    return jsonify({"success": True, "message": "UDP streaming stopped"})


@app.route("/api/sampling", methods=["POST"])
def update_sampling():
    """Update sampling interval"""
    try:
        data = request.get_json()
        interval = float(data.get("interval", 0.1))

        if interval < 0.01:
            interval = 0.01

        streamer.update_sampling_interval(interval)
        return jsonify({"success": True, "message": f"Interval updated to {interval}s"})

    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 400


@app.route("/api/csv/start", methods=["POST"])
def start_csv_recording_legacy():
    """Start CSV recording independently (legacy endpoint)"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    if streamer.data_streamer.start_csv_recording():
        return jsonify({"success": True, "message": "CSV recording started"})
    else:
        return (
            jsonify({"success": False, "message": "Error starting CSV recording"}),
            500,
        )


@app.route("/api/csv/stop", methods=["POST"])
def stop_csv_recording_legacy():
    """Stop CSV recording independently (legacy endpoint)"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    streamer.data_streamer.stop_csv_recording()
    return jsonify({"success": True, "message": "CSV recording stopped"})


@app.route("/api/csv/recording/start", methods=["POST"])
def start_csv_recording():
    """Start CSV recording independently of UDP streaming"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    if streamer.data_streamer.start_csv_recording():
        return jsonify({"success": True, "message": "CSV recording started"})
    else:
        return (
            jsonify({"success": False, "message": "Error starting CSV recording"}),
            500,
        )


@app.route("/api/csv/recording/stop", methods=["POST"])
def stop_csv_recording():
    """Stop CSV recording independently of UDP streaming"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    streamer.data_streamer.stop_csv_recording()
    return jsonify({"success": True, "message": "CSV recording stopped"})


# 🔑 NEW: UDP Streaming Control (Independent)
@app.route("/api/udp/streaming/start", methods=["POST"])
def start_udp_streaming():
    """Start UDP streaming to PlotJuggler independently of CSV recording"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    if streamer.data_streamer.start_udp_streaming():
        return jsonify(
            {"success": True, "message": "UDP streaming to PlotJuggler started"}
        )
    else:
        return (
            jsonify({"success": False, "message": "Error starting UDP streaming"}),
            500,
        )


@app.route("/api/udp/streaming/stop", methods=["POST"])
def stop_udp_streaming():
    """Stop UDP streaming to PlotJuggler independently of CSV recording"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    streamer.data_streamer.stop_udp_streaming()
    return jsonify({"success": True, "message": "UDP streaming to PlotJuggler stopped"})


# 🔍 HEALTH CHECK ENDPOINT
@app.route("/api/health", methods=["GET"])
def health_check():
    """Simple health check endpoint"""
    try:
        streamer_status = "initialized" if streamer is not None else "not_initialized"
        plot_manager_status = (
            "available"
            if (
                streamer
                and hasattr(streamer, "data_streamer")
                and hasattr(streamer.data_streamer, "plot_manager")
            )
            else "not_available"
        )

        return jsonify(
            {
                "status": "ok",
                "streamer": streamer_status,
                "plot_manager": plot_manager_status,
                "timestamp": time.time(),
            }
        )
    except Exception as e:
        return (
            jsonify({"status": "error", "error": str(e), "timestamp": time.time()}),
            500,
        )


# 📈 PLOT MANAGER API ENDPOINTS
@app.route("/api/plots", methods=["GET"])
def get_plots():
    """Get all plot sessions status"""
    print("🔍 DEBUG: /api/plots endpoint called")

    error_response = check_streamer_initialized()
    if error_response:
        print("❌ DEBUG: Streamer not initialized")
        return error_response

    print("✅ DEBUG: Streamer is initialized")

    try:
        print("🔍 DEBUG: Accessing streamer.data_streamer.plot_manager...")
        plot_manager = streamer.data_streamer.plot_manager
        print(f"✅ DEBUG: Plot manager obtained: {type(plot_manager)}")

        print("🔍 DEBUG: Calling get_all_sessions_status()...")
        sessions = plot_manager.get_all_sessions_status()
        print(f"✅ DEBUG: Sessions obtained: {len(sessions)} sessions")
        print(f"📊 DEBUG: Sessions data: {sessions}")

        result = {"sessions": sessions}
        print(f"✅ DEBUG: Returning result: {result}")
        return jsonify(result)
    except Exception as e:
        print(f"💥 DEBUG: Exception in get_plots: {type(e).__name__}: {str(e)}")
        import traceback

        print(f"📋 DEBUG: Full traceback:")
        traceback.print_exc()
        return jsonify({"error": str(e)}), 500


@app.route("/api/plots", methods=["POST"])
def create_plot():
    """Create a new plot session"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()

        # Validar datos requeridos
        if not data.get("variables"):
            return jsonify({"error": "At least one variable is required"}), 400

        if not data.get("time_window"):
            return jsonify({"error": "Time window is required"}), 400

        # Validar que las variables existen en datasets activos
        available_vars = streamer.data_streamer.plot_manager.get_available_variables(
            streamer.data_streamer.get_active_datasets(),
            streamer.config_manager.datasets,
        )

        invalid_vars = [var for var in data["variables"] if var not in available_vars]
        if invalid_vars:
            return (
                jsonify(
                    {
                        "error": f"Variables not available: {', '.join(invalid_vars)}",
                        "available_variables": available_vars,
                    }
                ),
                400,
            )

        # Validar trigger si está habilitado
        if data.get("trigger_enabled") and data.get("trigger_variable"):
            boolean_vars = streamer.data_streamer.plot_manager.get_boolean_variables(
                streamer.data_streamer.get_active_datasets(),
                streamer.config_manager.datasets,
            )

            if data["trigger_variable"] not in boolean_vars:
                return (
                    jsonify(
                        {
                            "error": f"Trigger variable '{data['trigger_variable']}' is not a boolean variable",
                            "boolean_variables": boolean_vars,
                        }
                    ),
                    400,
                )

        # Crear configuración de la sesión
        config = {
            "id": data.get("id"),  # Use the plot ID from the definition
            "name": data.get(
                "name", f"Plot {len(streamer.data_streamer.plot_manager.sessions) + 1}"
            ),
            "variables": data["variables"],
            "time_window": int(data["time_window"]),
            "y_min": data.get("y_min"),
            "y_max": data.get("y_max"),
            "trigger_variable": data.get("trigger_variable"),
            "trigger_enabled": data.get("trigger_enabled", False),
            "trigger_on_true": data.get("trigger_on_true", True),
        }

        # Convertir valores numéricos si están presentes
        if config["y_min"] is not None:
            config["y_min"] = float(config["y_min"])
        if config["y_max"] is not None:
            config["y_max"] = float(config["y_max"])

        session_id = streamer.data_streamer.plot_manager.create_session(config)

        return jsonify(
            {
                "success": True,
                "session_id": session_id,
                "message": f"Plot session '{config['name']}' created successfully",
            }
        )

    except Exception as e:
        return jsonify({"error": str(e)}), 500


@app.route("/api/plots/<session_id>", methods=["DELETE"])
def remove_plot(session_id):
    """Remove a plot session"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        success = streamer.data_streamer.plot_manager.remove_session(session_id)
        if success:
            return jsonify({"success": True, "message": "Plot session removed"})
        else:
            return jsonify({"error": "Plot session not found"}), 404
    except Exception as e:
        return jsonify({"error": str(e)}), 500


@app.route("/api/plots/<session_id>/control", methods=["POST"])
def control_plot(session_id):
    """Control a plot session (start/stop/pause/resume/clear)"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()
        action = data.get("action")

        if action not in ["start", "stop", "pause", "resume", "clear"]:
            return (
                jsonify(
                    {"error": "Invalid action. Use: start, stop, pause, resume, clear"}
                ),
                400,
            )

        success = streamer.data_streamer.plot_manager.control_session(
            session_id, action
        )
        if success:
            return jsonify({"success": True, "message": f"Plot session {action}ed"})
        else:
            return jsonify({"error": "Plot session not found"}), 404
    except Exception as e:
        return jsonify({"error": str(e)}), 500


@app.route("/api/plots/<session_id>/data", methods=["GET"])
def get_plot_data(session_id):
    """Get plot data for a specific session"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        plot_data = streamer.data_streamer.plot_manager.get_session_data(session_id)
        if plot_data:
            return jsonify(plot_data)
        else:
            return jsonify({"error": "Plot session not found"}), 404
    except Exception as e:
        return jsonify({"error": str(e)}), 500


@app.route("/api/plots/<session_id>/config", methods=["GET"])
def get_plot_config(session_id):
    """Get plot configuration for a specific session"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        config = streamer.data_streamer.plot_manager.get_session_config(session_id)
        if config:
            return jsonify({"success": True, "config": config})
        else:
            return jsonify({"error": "Plot session not found"}), 404
    except Exception as e:
        return jsonify({"error": str(e)}), 500


@app.route("/api/plots/<session_id>/config", methods=["PUT"])
def update_plot_config(session_id):
    """Update plot configuration for a specific session"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        data = request.get_json()

        # Validar datos requeridos
        if not data.get("variables"):
            return jsonify({"error": "At least one variable is required"}), 400

        if not data.get("time_window"):
            return jsonify({"error": "Time window is required"}), 400

        # Validar que las variables existen en datasets activos
        available_vars = streamer.data_streamer.plot_manager.get_available_variables(
            streamer.data_streamer.get_active_datasets(),
            streamer.config_manager.datasets,
        )

        invalid_vars = [var for var in data["variables"] if var not in available_vars]
        if invalid_vars:
            return (
                jsonify(
                    {
                        "error": f"Variables not available: {', '.join(invalid_vars)}",
                        "available_variables": available_vars,
                    }
                ),
                400,
            )

        # Validar trigger si está habilitado
        if data.get("trigger_enabled") and data.get("trigger_variable"):
            boolean_vars = streamer.data_streamer.plot_manager.get_boolean_variables(
                streamer.data_streamer.get_active_datasets(),
                streamer.config_manager.datasets,
            )

            if data["trigger_variable"] not in boolean_vars:
                return (
                    jsonify(
                        {
                            "error": f"Trigger variable '{data['trigger_variable']}' is not a boolean variable",
                            "boolean_variables": boolean_vars,
                        }
                    ),
                    400,
                )

        # Crear configuración actualizada
        config = {
            "name": data.get("name", f"Plot {session_id}"),
            "variables": data["variables"],
            "time_window": int(data["time_window"]),
            "y_min": data.get("y_min"),
            "y_max": data.get("y_max"),
            "trigger_variable": data.get("trigger_variable"),
            "trigger_enabled": data.get("trigger_enabled", False),
            "trigger_on_true": data.get("trigger_on_true", True),
        }

        # Convertir valores numéricos si están presentes
        if config["y_min"] is not None:
            config["y_min"] = float(config["y_min"])
        if config["y_max"] is not None:
            config["y_max"] = float(config["y_max"])

        # Actualizar configuración
        success = streamer.data_streamer.plot_manager.update_session_config(
            session_id, config
        )

        if success:
            return jsonify(
                {
                    "success": True,
                    "message": f"Plot session '{config['name']}' updated successfully",
                }
            )
        else:
            return jsonify({"error": "Plot session not found"}), 404

    except Exception as e:
        return jsonify({"error": str(e)}), 500


@app.route("/api/plots/variables", methods=["GET"])
def get_plot_variables():
    """Get available variables for plotting"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        available_vars = streamer.data_streamer.plot_manager.get_available_variables(
            streamer.data_streamer.get_active_datasets(),
            streamer.config_manager.datasets,
        )

        boolean_vars = streamer.data_streamer.plot_manager.get_boolean_variables(
            streamer.data_streamer.get_active_datasets(),
            streamer.config_manager.datasets,
        )

        return jsonify(
            {
                "available_variables": available_vars,
                "boolean_variables": boolean_vars,
                "active_datasets_count": len(
                    streamer.data_streamer.get_active_datasets()
                ),
            }
        )
    except Exception as e:
        return jsonify({"error": str(e)}), 500


@app.route("/api/status")
def get_status():
    """Get current status"""
    if streamer is None:
        return jsonify({"error": "Application not initialized"}), 503
    return jsonify(streamer.get_status())


@app.route("/api/plc/reconnection/status")
def get_plc_reconnection_status():
    """Get detailed PLC reconnection status"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        status = streamer.plc_client.get_reconnection_status()
        connection_info = streamer.plc_client.get_connection_info()

        return jsonify(
            {"success": True, "reconnection": status, "connection": connection_info}
        )
    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/plc/reconnection/enable", methods=["POST"])
def enable_plc_reconnection():
    """Enable automatic PLC reconnection"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        streamer.plc_client.enable_automatic_reconnection(True)
        return jsonify(
            {"success": True, "message": "Automatic PLC reconnection enabled"}
        )
    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/plc/reconnection/disable", methods=["POST"])
def disable_plc_reconnection():
    """Disable automatic PLC reconnection"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        streamer.plc_client.enable_automatic_reconnection(False)
        return jsonify(
            {"success": True, "message": "Automatic PLC reconnection disabled"}
        )
    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/events")
def get_events():
    """Get recent events from the application log"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    try:
        limit = request.args.get("limit", 50, type=int)
        limit = min(limit, 200)  # Maximum 200 events per request

        events = streamer.get_recent_events(limit)
        return jsonify(
            {
                "success": True,
                "events": events,
                "total_events": len(streamer.event_logger.events_log),
                "showing": len(events),
            }
        )
    except Exception as e:
        return jsonify({"success": False, "error": str(e)}), 500


@app.route("/api/stream/variables", methods=["GET"])
def stream_variables():
    """Stream variable values in real-time using Server-Sent Events"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    # Get request parameters outside the generator
    dataset_id = request.args.get("dataset_id")
    interval = float(request.args.get("interval", 1.0))  # Default 1 second

    if not dataset_id:
        return jsonify({"error": "Dataset ID required"}), 400

    if dataset_id not in streamer.datasets:
        return jsonify({"error": f"Dataset {dataset_id} not found"}), 404

    def generate():
        """Generate SSE data stream - CACHE ONLY"""

        # Send initial connection message
        yield f"data: {json.dumps({'type': 'connected', 'message': 'SSE connection established - monitoring cache'})}\n\n"

        last_values = {}

        while True:
            try:
                # Check basic preconditions for cache availability
                if not streamer.plc_client.is_connected():
                    # PLC not connected - cache won't be populated
                    data = {
                        "type": "plc_disconnected",
                        "message": "PLC not connected - cache not being populated",
                        "timestamp": datetime.now().isoformat(),
                    }
                    yield f"data: {json.dumps(data)}\n\n"
                    time.sleep(interval)
                    continue

                # Check if dataset is active
                if dataset_id not in streamer.active_datasets:
                    data = {
                        "type": "dataset_inactive",
                        "message": f"Dataset '{dataset_id}' is not active - activate to populate cache",
                        "timestamp": datetime.now().isoformat(),
                    }
                    yield f"data: {json.dumps(data)}\n\n"
                    time.sleep(interval)
                    continue

                # Get dataset variables
                dataset_variables = streamer.get_dataset_variables(dataset_id)

                if not dataset_variables:
                    # No variables in dataset
                    data = {
                        "type": "no_variables",
                        "message": "No variables defined in this dataset",
                        "timestamp": datetime.now().isoformat(),
                    }
                    yield f"data: {json.dumps(data)}\n\n"
                    time.sleep(interval)
                    continue

                # Get cached values - the ONLY source according to application principles
                if not streamer.has_cached_values(dataset_id):
                    # No cache available yet - dataset might be starting up
                    sampling_interval = (
                        streamer.config_manager.get_dataset_sampling_interval(
                            dataset_id
                        )
                    )
                    data = {
                        "type": "no_cache",
                        "message": f"Waiting for cache to be populated (dataset reads every {sampling_interval}s)",
                        "timestamp": datetime.now().isoformat(),
                        "sampling_interval": sampling_interval,
                    }
                    yield f"data: {json.dumps(data)}\n\n"
                    time.sleep(interval)
                    continue

                # Get cached values (the ONLY valid source)
                read_result = streamer.get_cached_dataset_values(dataset_id)

                if read_result.get("success", False):
                    values = read_result.get("values", {})
                    timestamp = read_result.get("timestamp", datetime.now().isoformat())

                    # Format values for display
                    formatted_values = {}
                    for var_name, value in values.items():
                        if value is not None:
                            var_config = dataset_variables[var_name]
                            var_type = var_config.get("type", "unknown")

                            try:
                                if var_type == "real":
                                    formatted_values[var_name] = (
                                        f"{value:.3f}"
                                        if isinstance(value, (int, float))
                                        else str(value)
                                    )
                                elif var_type == "bool":
                                    formatted_values[var_name] = (
                                        "TRUE" if value else "FALSE"
                                    )
                                elif var_type in [
                                    "int",
                                    "uint",
                                    "dint",
                                    "udint",
                                    "word",
                                    "byte",
                                    "sint",
                                    "usint",
                                ]:
                                    formatted_values[var_name] = (
                                        str(int(value))
                                        if isinstance(value, (int, float))
                                        else str(value)
                                    )
                                else:
                                    formatted_values[var_name] = str(value)
                            except:
                                formatted_values[var_name] = "FORMAT_ERROR"
                        else:
                            formatted_values[var_name] = "ERROR"

                    # Only send if values changed
                    if formatted_values != last_values:
                        data = {
                            "type": "values",
                            "values": formatted_values,
                            "timestamp": timestamp,
                            "source": "cache",
                            "stats": read_result.get("stats", {}),
                            "cache_age_info": f"Dataset reads every {streamer.config_manager.get_dataset_sampling_interval(dataset_id)}s",
                        }
                        yield f"data: {json.dumps(data)}\n\n"
                        last_values = formatted_values.copy()
                else:
                    # Send error data from cache
                    error_data = {
                        "type": "cache_error",
                        "message": read_result.get(
                            "error", "Cached data indicates error"
                        ),
                        "timestamp": datetime.now().isoformat(),
                        "error_type": read_result.get("error_type", "unknown"),
                        "source": "cache",
                    }
                    yield f"data: {json.dumps(error_data)}\n\n"

                time.sleep(interval)

            except Exception as e:
                error_data = {
                    "type": "stream_error",
                    "message": f"SSE stream error: {str(e)}",
                    "timestamp": datetime.now().isoformat(),
                    "source": "cache_monitoring",
                }
                yield f"data: {json.dumps(error_data)}\n\n"
                time.sleep(interval)

    return Response(
        generate(),
        mimetype="text/event-stream",
        headers={
            "Cache-Control": "no-cache",
            "Connection": "keep-alive",
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Headers": "Cache-Control",
        },
    )


@app.route("/api/stream/status", methods=["GET"])
def stream_status():
    """Stream application status in real-time using Server-Sent Events"""
    error_response = check_streamer_initialized()
    if error_response:
        return error_response

    # Get request parameters outside the generator
    interval = float(request.args.get("interval", 2.0))  # Default 2 seconds

    def generate():
        """Generate SSE status stream"""
        last_status = None

        # Send initial connection message
        yield f"data: {json.dumps({'type': 'connected', 'message': 'Status stream connected'})}\n\n"

        while True:
            try:
                # Get current status
                current_status = streamer.get_status()

                # Only send if status changed
                if current_status != last_status:
                    data = {
                        "type": "status",
                        "status": current_status,
                        "timestamp": datetime.now().isoformat(),
                    }
                    yield f"data: {json.dumps(data)}\n\n"
                    last_status = current_status

                time.sleep(interval)

            except Exception as e:
                error_data = {
                    "type": "error",
                    "message": f"Status stream error: {str(e)}",
                    "timestamp": datetime.now().isoformat(),
                }
                yield f"data: {json.dumps(error_data)}\n\n"
                time.sleep(interval)

    return Response(
        generate(),
        mimetype="text/event-stream",
        headers={
            "Cache-Control": "no-cache",
            "Connection": "keep-alive",
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Headers": "Cache-Control",
        },
    )


def graceful_shutdown():
    """Perform graceful shutdown"""
    print("\n⏹️  Performing graceful shutdown...")
    try:
        streamer.stop_streaming()
        streamer.disconnect_plc()
        streamer.release_instance_lock()
        print("✅ Shutdown completed successfully")
    except Exception as e:
        print(f"⚠️  Error during shutdown: {e}")


def main():
    """Main application entry point with error handling and recovery"""
    max_retries = 3
    retry_count = 0

    while retry_count < max_retries:
        try:
            # Create templates directory if it doesn't exist
            os.makedirs("templates", exist_ok=True)

            print("🚀 Starting Flask server for PLC S7-315 Streamer")
            print("📊 Web interface available at: http://localhost:5050")
            print("🔧 Configure your PLC and variables through the web interface")

            # Initialize streamer (this will handle instance locking and auto-recovery)
            global streamer

            # Start Flask application
            app.run(debug=False, host="0.0.0.0", port=5050, use_reloader=False)

            # If we reach here, the server stopped normally
            break

        except RuntimeError as e:
            if "Another instance" in str(e):
                print(f"❌ {e}")
                print("💡 Tip: Stop the other instance or wait for it to finish")
                sys.exit(1)
            else:
                print(f"⚠️  Runtime error: {e}")
                retry_count += 1

        except KeyboardInterrupt:
            print("\n⏸️  Received interrupt signal...")
            graceful_shutdown()
            break

        except Exception as e:
            print(f"💥 Unexpected error: {e}")
            retry_count += 1

            if retry_count < max_retries:
                print(f"🔄 Attempting restart ({retry_count}/{max_retries})...")
                time.sleep(2)  # Wait before retry
            else:
                print("❌ Maximum retries reached. Exiting...")
                graceful_shutdown()
                sys.exit(1)


if __name__ == "__main__":
    try:
        # Initialize streamer instance
        streamer = PLCDataStreamer()
        main()
    except Exception as e:
        print(f"💥 Critical error during initialization: {e}")
        sys.exit(1)