from flask import Flask, render_template, request, jsonify, send_file
from werkzeug.exceptions import RequestEntityTooLarge
import os
import json
import datetime

app = Flask(__name__)
app.config['MAX_CONTENT_LENGTH'] = 16 * 1024 * 1024  # 16MB max upload

# Data storage path
DATA_DIR = os.path.join(os.path.dirname(__file__), 'data')
os.makedirs(DATA_DIR, exist_ok=True)

@app.errorhandler(RequestEntityTooLarge)
def handle_file_too_large(e):
    return jsonify({"success": False, "message": "File too large. Maximum size is 16MB."}), 413

@app.errorhandler(404)
def page_not_found(e):
    return render_template('index.html'), 404

@app.route('/')
def index():
    return render_template('index.html')

@app.route('/health')
def health_check():
    return "OK", 200

@app.route('/api/save', methods=['POST'])
def save_project():
    try:
        data = request.json
        if not data:
            return jsonify({"success": False, "message": "No data provided"}), 400
            
        project_name = data.get('projectName', 'untitled')
        # Sanitize filename
        safe_name = "".join([c for c in project_name if c.isalpha() or c.isdigit() or c in (' ', '-', '_')]).strip()
        if not safe_name:
            safe_name = 'untitled'
        
        filename = f"{safe_name}.json"
        filepath = os.path.join(DATA_DIR, filename)
        
        with open(filepath, 'w', encoding='utf-8') as f:
            json.dump(data, f, ensure_ascii=False, indent=2)
            
        return jsonify({"success": True, "message": "项目已保存", "filename": filename})
    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 500

@app.route('/api/load', methods=['GET'])
def load_projects():
    try:
        if not os.path.exists(DATA_DIR):
            os.makedirs(DATA_DIR, exist_ok=True)
            
        files = [f for f in os.listdir(DATA_DIR) if f.endswith('.json')]
        projects = []
        for f in files:
            filepath = os.path.join(DATA_DIR, f)
            try:
                with open(filepath, 'r', encoding='utf-8') as file:
                    data = json.load(file)
                    projects.append({
                        "filename": f,
                        "projectName": data.get('projectName', f.replace('.json', '')),
                        "updatedAt": datetime.datetime.fromtimestamp(os.path.getmtime(filepath)).strftime('%Y-%m-%d %H:%M:%S')
                    })
            except:
                continue
        # Sort by update time desc
        projects.sort(key=lambda x: x['updatedAt'], reverse=True)
        return jsonify({"success": True, "projects": projects})
    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 500

@app.route('/api/load/<filename>', methods=['GET'])
def load_project_detail(filename):
    try:
        # Security check
        if '..' in filename or not filename.endswith('.json'):
            return jsonify({"success": False, "message": "Invalid filename"}), 400
            
        filepath = os.path.join(DATA_DIR, filename)
        if not os.path.exists(filepath):
            return jsonify({"success": False, "message": "File not found"}), 404
            
        with open(filepath, 'r', encoding='utf-8') as f:
            data = json.load(f)
            return jsonify({"success": True, "data": data})
    except Exception as e:
        return jsonify({"success": False, "message": str(e)}), 500

if __name__ == '__main__':
    # Use 7860 for Hugging Face Spaces default
    port = int(os.environ.get('PORT', 7860))
    app.run(debug=True, host='0.0.0.0', port=port)