app.py

from flask import Flask, render_template, request, jsonify, send_file
import os
import json
import uuid
import shutil
from datetime import datetime

app = Flask(__name__)
app.config['MAX_CONTENT_LENGTH'] = 5 * 1024 * 1024  # 5MB Limit

# Configuration
DATA_DIR = os.path.join(os.path.dirname(__file__), 'data')
SOP_FILE = os.path.join(DATA_DIR, 'sops.json')
DEFAULT_SOP_FILE = os.path.join(os.path.dirname(__file__), 'sops_default.json')

os.makedirs(DATA_DIR, exist_ok=True)

# Initialize data file if not exists
if not os.path.exists(SOP_FILE):
    if os.path.exists(DEFAULT_SOP_FILE):
        try:
            shutil.copy(DEFAULT_SOP_FILE, SOP_FILE)
            print(f"Initialized {SOP_FILE} from default data.")
        except Exception as e:
            print(f"Error copying default data: {e}")
            # Fallback to empty list
            with open(SOP_FILE, 'w', encoding='utf-8') as f:
                json.dump([], f)
    else:
        with open(SOP_FILE, 'w', encoding='utf-8') as f:
            json.dump([], f)

# Error Handlers
@app.errorhandler(404)
def not_found_error(error):
    if request.path.startswith('/api/'):
        return jsonify({'error': '资源未找到'}), 404
    return render_template('index.html'), 404

@app.errorhandler(500)
def internal_error(error):
    if request.path.startswith('/api/'):
        return jsonify({'error': '服务器内部错误'}), 500
    return "服务器内部错误", 500

@app.errorhandler(413)
def request_entity_too_large(error):
    return jsonify({'error': '文件过大 (最大 5MB)'}), 413

class DataStore:
    @staticmethod
    def load_sops():
        try:
            with open(SOP_FILE, 'r', encoding='utf-8') as f:
                return json.load(f)
        except Exception as e:
            print(f"Error loading SOPs: {e}")
            return []

    @staticmethod
    def save_sops(sops):
        try:
            with open(SOP_FILE, 'w', encoding='utf-8') as f:
                json.dump(sops, f, ensure_ascii=False, indent=2)
            return True
        except Exception as e:
            print(f"Error saving SOPs: {e}")
            return False

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

@app.route('/api/sops', methods=['GET'])
def get_sops():
    sops = DataStore.load_sops()
    # Sort by updated_at desc
    sops.sort(key=lambda x: x.get('updated_at', ''), reverse=True)
    return jsonify(sops)

@app.route('/api/sops', methods=['POST'])
def create_sop():
    data = request.json
    sops = DataStore.load_sops()
    
    new_sop = {
        'id': str(uuid.uuid4()),
        'title': data.get('title', '未命名 SOP'),
        'category': data.get('category', '通用'),
        'version': '1.0',
        'status': 'draft', # draft, review, published
        'created_at': datetime.now().isoformat(),
        'updated_at': datetime.now().isoformat(),
        'content': {
            'purpose': '',
            'scope': '',
            'prerequisites': [],
            'roles': [],
            'steps': [], # Array of {id, title, description, role}
            'flowchart': '', # Mermaid syntax
            'troubleshooting': []
        }
    }
    
    sops.append(new_sop)
    DataStore.save_sops(sops)
    return jsonify(new_sop)

@app.route('/api/sops/<sop_id>', methods=['PUT'])
def update_sop(sop_id):
    data = request.json
    sops = DataStore.load_sops()
    
    for sop in sops:
        if sop['id'] == sop_id:
            sop.update(data)
            sop['updated_at'] = datetime.now().isoformat()
            DataStore.save_sops(sops)
            return jsonify(sop)
            
    return jsonify({'error': 'SOP not found'}), 404

@app.route('/api/sops/<sop_id>', methods=['DELETE'])
def delete_sop(sop_id):
    sops = DataStore.load_sops()
    sops = [s for s in sops if s['id'] != sop_id]
    DataStore.save_sops(sops)
    return jsonify({'success': True})

@app.route('/api/import', methods=['POST'])
def import_sop():
    if 'file' not in request.files:
        return jsonify({'error': '未找到文件部分'}), 400
    
    file = request.files['file']
    if file.filename == '':
        return jsonify({'error': '未选择文件'}), 400
        
    if not file.filename.lower().endswith('.json'):
        return jsonify({'error': '文件类型无效。仅支持 JSON 格式。'}), 400

    try:
        # Read file content
        content = file.read()

        if len(content) > 5 * 1024 * 1024:  # 5MB limit
            return jsonify({'error': '文件过大 (超过 5MB)'}), 413
        
        # Null byte check (Binary check)
        if b'\0' in content:
            return jsonify({'error': '检测到二进制内容或空字节'}), 400
            
        # Parse JSON
        try:
            json_content = json.loads(content.decode('utf-8'))
        except UnicodeDecodeError:
            return jsonify({'error': '文件编码错误。需要 UTF-8 编码。'}), 400
        except json.JSONDecodeError:
            return jsonify({'error': 'JSON 格式无效'}), 400
            
        # Validate structure (Basic)
        if isinstance(json_content, list):
            items = json_content
        elif isinstance(json_content, dict):
            items = [json_content]
        else:
            return jsonify({'error': '无效的 JSON 结构。必须是列表或对象。'}), 400
            
        valid_sops = []
        for item in items:
            # Basic validation
            if 'title' in item and 'content' in item:
                # Ensure ID is unique or generate new one
                if 'id' not in item:
                    item['id'] = str(uuid.uuid4())
                valid_sops.append(item)
        
        if not valid_sops:
            return jsonify({'error': '文件中未发现有效的 SOP 数据'}), 400
            
        # Save
        current_sops = DataStore.load_sops()
        # Strategy: Append. If ID exists, overwrite? Let's just append/overwrite based on ID.
        existing_ids = {s['id']: i for i, s in enumerate(current_sops)}
        
        count = 0
        for sop in valid_sops:
            if sop['id'] in existing_ids:
                current_sops[existing_ids[sop['id']]] = sop
            else:
                current_sops.append(sop)
            count += 1
            
        DataStore.save_sops(current_sops)
        return jsonify({'success': True, 'count': count, 'message': f'成功导入 {count} 个 SOP'})
        
    except Exception as e:
        print(f"Import error: {e}")
        return jsonify({'error': str(e)}), 500

@app.route('/api/export/<sop_id>', methods=['GET'])
def export_sop(sop_id):
    # This could be a specialized export endpoint, 
    # but for now frontend handles most exports.
    # Placeholder for future server-side PDF generation if needed.
    pass

if __name__ == '__main__':
    # Use environment variable to control debug mode, default to True for local dev
    debug_mode = os.environ.get('FLASK_DEBUG', 'true').lower() == 'true'
    app.run(host='0.0.0.0', port=7860, debug=debug_mode)