"""
Example Flask application for PyServe ASGI mounting.

This demonstrates how to create a Flask application that can be
mounted at a specific path in PyServe (via WSGI-to-ASGI adapter).
"""

from typing import Optional

try:
    from flask import Flask, jsonify, request
except ImportError:
    raise ImportError(
        "Flask is not installed. Install with: pip install flask"
    )


app = Flask(__name__)

users_db = {
    1: {"id": 1, "name": "Alice", "email": "alice@example.com"},
    2: {"id": 2, "name": "Bob", "email": "bob@example.com"},
}


@app.route("/")
def root():
    return jsonify({"message": "Welcome to Flask mounted in PyServe!"})


@app.route("/health")
def health_check():
    return jsonify({"status": "healthy", "app": "flask"})


@app.route("/users")
def list_users():
    return jsonify({"users": list(users_db.values()), "count": len(users_db)})


@app.route("/users/<int:user_id>")
def get_user(user_id: int):
    if user_id not in users_db:
        return jsonify({"error": "User not found"}), 404
    return jsonify(users_db[user_id])


@app.route("/users", methods=["POST"])
def create_user():
    data = request.get_json()
    if not data or "name" not in data:
        return jsonify({"error": "Name is required"}), 400

    new_id = max(users_db.keys()) + 1 if users_db else 1
    users_db[new_id] = {
        "id": new_id,
        "name": data["name"],
        "email": data.get("email", ""),
    }
    return jsonify({"message": f"User created with ID {new_id}", "user": users_db[new_id]}), 201


@app.route("/users/<int:user_id>", methods=["PUT"])
def update_user(user_id: int):
    if user_id not in users_db:
        return jsonify({"error": "User not found"}), 404

    data = request.get_json()
    if data:
        if "name" in data:
            users_db[user_id]["name"] = data["name"]
        if "email" in data:
            users_db[user_id]["email"] = data["email"]

    return jsonify({"message": f"User {user_id} updated", "user": users_db[user_id]})


@app.route("/users/<int:user_id>", methods=["DELETE"])
def delete_user(user_id: int):
    if user_id not in users_db:
        return jsonify({"error": "User not found"}), 404

    del users_db[user_id]
    return jsonify({"message": f"User {user_id} deleted"})


def create_app(config: Optional[dict] = None) -> Flask:
    application = Flask(__name__)

    if config:
        application.config.update(config)

    @application.route("/")
    def factory_root():
        return jsonify({
            "message": "Welcome to Flask (factory) mounted in PyServe!",
            "config": config or {},
        })

    @application.route("/health")
    def factory_health():
        return jsonify({"status": "healthy", "app": "flask-factory"})

    @application.route("/echo/<message>")
    def echo(message: str):
        return jsonify({"echo": message})

    return application


if __name__ == "__main__":
    app.run(host="0.0.0.0", port=8002, debug=True)