"""Flask REST API server for Email Triage OpenEnv."""

import os
from pathlib import Path

from flask import Flask, request, jsonify, render_template, send_file

from environment.env import EmailTriageEnv
from environment.types import Action

app = Flask(__name__, template_folder=os.path.join(os.path.dirname(__file__), 'templates'))

# Global environment instances (one per task)
environments = {}

def get_env(task_name: str = "spam_detection") -> EmailTriageEnv:
    """Get or create environment for task"""
    if task_name not in environments:
        environments[task_name] = EmailTriageEnv(task_name=task_name)
    return environments[task_name]

@app.route("/", methods=["GET"])
def index():
    """Root endpoint - Interactive dashboard"""
    try:
        return render_template("index.html")
    except Exception:
        # Fallback: read HTML file directly
        html_path = os.path.join(os.path.dirname(__file__), 'templates', 'index.html')
        if os.path.exists(html_path):
            with open(html_path, 'r', encoding='utf-8') as f:
                return f.read()
        return jsonify({
            "status": "ok",
            "message": "Email Triage OpenEnv API",
            "version": "1.0.0",
            "note": "Dashboard not available. Use API endpoints directly.",
            "endpoints": {
                "health": "GET /health",
                "tasks": "GET /tasks",
                "reset": "POST /reset?task=spam_detection",
                "step": "POST /step?task=spam_detection",
                "state": "GET /state?task=spam_detection",
                "state-describe": "GET /state-describe?task=spam_detection"
            }
        }), 200

@app.route("/health", methods=["GET"])
def health():
    """Health check endpoint"""
    return jsonify({"status": "ok"}), 200

@app.route("/reset", methods=["POST"])
def reset():
    """Reset environment - POST /reset?task=spam_detection"""
    task_name = request.args.get("task", "spam_detection")
    env = get_env(task_name)
    obs = env.reset()
    return jsonify({
        "observation": obs.model_dump(mode="json"),
        "task": task_name
    }), 200

@app.route("/step", methods=["POST"])
def step():
    """Step environment - POST /step with JSON action"""
    task_name = request.args.get("task", "spam_detection")
    env = get_env(task_name)

    data = request.get_json()
    if not data:
        return jsonify({"error": "No action provided"}), 400

    try:
        action = Action(
            classification=data.get("classification"),
            team=data.get("team", "none"),
            priority=int(data.get("priority", 1))
        )
    except Exception as e:
        return jsonify({"error": f"Invalid action: {str(e)}"}), 400

    obs, reward, done, info = env.step(action)

    return jsonify({
        "observation": obs.model_dump(mode="json"),
        "reward": reward.model_dump(mode="json"),
        "done": done,
        "info": info
    }), 200

@app.route("/state", methods=["GET"])
def state():
    """Get current state - GET /state?task=spam_detection"""
    task_name = request.args.get("task", "spam_detection")
    env = get_env(task_name)
    state = env.state()
    return jsonify(state.model_dump(mode="json")), 200

@app.route("/state-describe", methods=["GET"])
def state_describe():
    """Describe observation and action spaces"""
    task_name = request.args.get("task", "spam_detection")
    env = get_env(task_name)
    return jsonify({
        "observation_space": env.describe_observation_space(),
        "action_space": env.describe_action_space()
    }), 200

@app.route("/tasks", methods=["GET"])
def tasks():
    """List available tasks"""
    return jsonify({
        "tasks": [
            {
                "name": "spam_detection",
                "description": "Binary spam/non-spam classification",
                "difficulty": "easy",
                "num_emails": 10
            },
            {
                "name": "multi_class_routing",
                "description": "Multi-class classification with routing",
                "difficulty": "medium",
                "num_emails": 12
            },
            {
                "name": "context_aware_triage",
                "description": "Complex context-aware triage with escalation",
                "difficulty": "hard",
                "num_emails": 20
            }
        ]
    }), 200


def main():
    """Main entry point for the server"""
    port = int(os.environ.get("PORT", 7860))
    app.run(host="0.0.0.0", port=port, debug=False)


if __name__ == "__main__":
    main()