from flask import Blueprint, request, jsonify
import logging
import re
from providers import ProviderFactory
from db import (
    is_within_allowed_window,
    get_access_windows,
    log_token_usage
)

api_bp = Blueprint('api', __name__)

@api_bp.route("/ask", methods=["POST"])
def ask_ai():
    logging.info("Incoming request")

    # Ensure incoming data is JSON
    if not request.is_json:
        return jsonify({"error": "Content-Type måste vara application/json"}), 400

    # Parse JSON safely
    try:
        data = request.get_json(force=True)
    except Exception as e:
        logging.warning("Invalid JSON payload: %s", e)
        return jsonify({"error": "Ogiltig JSON"}), 400

    # Validate API proxy key
    key = data.get("proxy_key")
    if not isinstance(key, str) or not re.fullmatch(r"[a-zA-Z0-9\-]{4,64}", key):
        return jsonify({"error": "Ogiltig eller saknad nyckel"}), 401

    # Check if the key has any valid access windows
    windows = get_access_windows(key)
    if not windows:
        return jsonify({"error": "Ogiltig eller saknad nyckel"}), 401

    # Enforce time-based access control
    if not is_within_allowed_window(windows):
        formatted_windows = [f"{w['start_datetime']}-{w['end_datetime']}" for w in windows]
        return jsonify({
            "error": "Åtkomst tillåten under följande tider: " + ", ".join(formatted_windows)
        }), 403

    # Validate prompt and system role inputs
    system_role = data.get("system_role")
    prompt = data.get("prompt")
    if not isinstance(system_role, str) or not isinstance(prompt, str):
        return jsonify({"error": "Prompt och systemroll måste vara text"}), 400

    if len(system_role) > 1000 or len(prompt) > 2000:
        return jsonify({"error": "Inmatning för lång"}), 400

    # Sanitize input to remove unwanted characters
    def sanitize(text):
        return re.sub(r"[<>]", "", text)
    system_role = sanitize(system_role)
    prompt = sanitize(prompt)

    # Call AI provider and handle response
    try:
        provider = ProviderFactory.get_provider()
        response_data = provider.generate_response(system_role, prompt)
        
        result = response_data["response"]
        usage = response_data["usage"]

        # Log token usage per key
        log_token_usage(
            key,
            usage["prompt_tokens"],
            usage["completion_tokens"],
            usage["total_tokens"]
        )
        logging.info("AI response returned (%d tokens) from provider: %s", 
                    usage["total_tokens"], provider.__class__.__name__)

        return jsonify({"response": result})

    except Exception as e:
        logging.error("AI provider error: %s", e)
        return jsonify({"error": "Ett fel inträffade vid kontakt med AI-tjänsten"}), 500