"""
技术论坛 - 后台管理系统
"""

from flask import Flask, render_template, jsonify, request
from flask_cors import CORS
import json
from pathlib import Path
from datetime import datetime

app = Flask(__name__)
CORS(app)

# 数据目录
DATA_DIR = Path(__file__).parent.parent / 'data'
USERS_FILE = DATA_DIR / 'users.json'
POSTS_FILE = DATA_DIR / 'posts.json'
TOPICS_FILE = DATA_DIR / 'topics.json'

def load_users():
    if USERS_FILE.exists():
        return json.loads(USERS_FILE.read_text(encoding='utf-8'))
    return {}

def load_posts():
    if POSTS_FILE.exists():
        return json.loads(POSTS_FILE.read_text(encoding='utf-8'))
    return {}

def load_topics():
    if TOPICS_FILE.exists():
        return json.loads(TOPICS_FILE.read_text(encoding='utf-8'))
    return {}

def save_users(users):
    USERS_FILE.write_text(json.dumps(users, ensure_ascii=False, indent=2), encoding='utf-8')

def save_posts(posts):
    POSTS_FILE.write_text(json.dumps(posts, ensure_ascii=False, indent=2), encoding='utf-8')

def save_topics(topics):
    TOPICS_FILE.write_text(json.dumps(topics, ensure_ascii=False, indent=2), encoding='utf-8')

# ============ 页面路由 ============

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

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

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

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

# ============ API路由 ============

@app.route('/api/stats')
def api_stats():
    users = load_users()
    posts = load_posts()
    topics = load_topics()
    
    # 统计
    total_messages = 0
    for post in posts.values():
        total_messages += len(post.get('replies', []))
    
    today = datetime.now().strftime('%Y-%m-%d')
    today_posts = sum(1 for p in posts.values() if p.get('created_at', '').startswith(today))
    today_users = sum(1 for u in users.values() if u.get('created_at', '').startswith(today))
    
    # 帖子类型统计
    discussion_count = sum(1 for p in posts.values() if p.get('type') == 'discussion')
    share_count = sum(1 for p in posts.values() if p.get('type') == 'share')
    
    return jsonify({
        'users_count': len(users),
        'posts_count': len(posts),
        'topics_count': len(topics),
        'messages_count': total_messages,
        'today_posts': today_posts,
        'today_users': today_users,
        'discussion_count': discussion_count,
        'share_count': share_count,
    })

@app.route('/api/users')
def api_users():
    users = load_users()
    posts = load_posts()
    
    user_list = []
    for uid, user in users.items():
        # 统计用户帖子和回复数
        posts_count = len(user.get('posts', []))
        replies_count = 0
        for post in posts.values():
            for reply in post.get('replies', []):
                if reply.get('author_id') == uid:
                    replies_count += 1
        
        user_list.append({
            'id': uid,
            'username': user.get('username', ''),
            'email': user.get('email', ''),
            'phone': user.get('phone', ''),
            'posts_count': posts_count,
            'replies_count': replies_count,
            'created_at': user.get('created_at', ''),
        })
    
    user_list.sort(key=lambda x: x['created_at'], reverse=True)
    return jsonify(user_list)

@app.route('/api/users/<user_id>', methods=['DELETE'])
def api_delete_user(user_id):
    users = load_users()
    posts = load_posts()
    topics = load_topics()
    
    if user_id not in users:
        return jsonify({'error': '用户不存在'}), 404
    
    # 删除用户的帖子
    for post_id in users[user_id].get('posts', []):
        if post_id in posts:
            del posts[post_id]
    
    # 从主题关注中移除
    for topic in topics.values():
        if user_id in topic.get('followers', []):
            topic['followers'].remove(user_id)
    
    # 删除用户
    del users[user_id]
    
    save_users(users)
    save_posts(posts)
    save_topics(topics)
    
    return jsonify({'success': True})

@app.route('/api/posts')
def api_posts():
    posts = load_posts()
    users = load_users()
    
    post_type = request.args.get('type')
    
    post_list = []
    for pid, post in posts.items():
        if post_type and post['type'] != post_type:
            continue
        
        author = users.get(post['author_id'], {})
        post_list.append({
            'id': pid,
            'title': post['title'],
            'type': post['type'],
            'author': author.get('username', '未知'),
            'author_id': post['author_id'],
            'likes': len(post.get('likes', [])),
            'replies': len(post.get('replies', [])),
            'views': post.get('views', 0),
            'is_pinned': post.get('is_pinned', False),
            'created_at': post['created_at'],
        })
    
    post_list.sort(key=lambda x: x['created_at'], reverse=True)
    return jsonify(post_list)

@app.route('/api/posts/<post_id>')
def api_post_detail(post_id):
    posts = load_posts()
    users = load_users()
    
    post = posts.get(post_id)
    if not post:
        return jsonify({'error': '帖子不存在'}), 404
    
    author = users.get(post['author_id'], {})
    
    # 获取回复
    replies = []
    for reply in post.get('replies', []):
        reply_author = users.get(reply['author_id'], {})
        replies.append({
            'id': reply['id'],
            'content': reply['content'][:100] + '...' if len(reply['content']) > 100 else reply['content'],
            'author': reply_author.get('username', '未知'),
            'likes': len(reply.get('likes', [])),
            'created_at': reply['created_at'],
        })
    
    return jsonify({
        'id': post_id,
        'title': post['title'],
        'content': post['content'],
        'type': post['type'],
        'author': author.get('username', '未知'),
        'tags': post.get('tags', []),
        'likes': len(post.get('likes', [])),
        'replies': replies,
        'views': post.get('views', 0),
        'is_pinned': post.get('is_pinned', False),
        'created_at': post['created_at'],
    })

@app.route('/api/posts/<post_id>', methods=['DELETE'])
def api_delete_post(post_id):
    posts = load_posts()
    users = load_users()
    
    if post_id not in posts:
        return jsonify({'error': '帖子不存在'}), 404
    
    author_id = posts[post_id].get('author_id')
    
    del posts[post_id]
    
    # 从用户列表中移除
    if author_id and author_id in users:
        if post_id in users[author_id].get('posts', []):
            users[author_id]['posts'].remove(post_id)
    
    save_posts(posts)
    save_users(users)
    
    return jsonify({'success': True})

@app.route('/api/posts/<post_id>/pin', methods=['POST'])
def api_pin_post(post_id):
    posts = load_posts()
    
    if post_id not in posts:
        return jsonify({'error': '帖子不存在'}), 404
    
    posts[post_id]['is_pinned'] = not posts[post_id].get('is_pinned', False)
    save_posts(posts)
    
    return jsonify({
        'success': True,
        'is_pinned': posts[post_id]['is_pinned']
    })

@app.route('/api/topics')
def api_topics():
    topics = load_topics()
    users = load_users()
    
    topic_list = []
    for tid, topic in topics.items():
        author = users.get(topic['author_id'], {})
        topic_list.append({
            'id': tid,
            'name': topic['name'],
            'icon': topic.get('icon', '🔧'),
            'author': author.get('username', '未知'),
            'sub_topics_count': len(topic.get('sub_topics', [])),
            'questions_count': len(topic.get('questions', [])),
            'followers_count': len(topic.get('followers', [])),
            'created_at': topic['created_at'],
        })
    
    topic_list.sort(key=lambda x: x['followers_count'], reverse=True)
    return jsonify(topic_list)

@app.route('/api/topics/<topic_id>')
def api_topic_detail(topic_id):
    topics = load_topics()
    users = load_users()
    
    topic = topics.get(topic_id)
    if not topic:
        return jsonify({'error': '主题不存在'}), 404
    
    author = users.get(topic['author_id'], {})
    
    return jsonify({
        'id': topic_id,
        'name': topic['name'],
        'description': topic.get('description', ''),
        'icon': topic.get('icon', '🔧'),
        'author': author.get('username', '未知'),
        'sub_topics': topic.get('sub_topics', []),
        'questions': topic.get('questions', []),
        'followers_count': len(topic.get('followers', [])),
        'created_at': topic['created_at'],
    })

@app.route('/api/topics/<topic_id>', methods=['DELETE'])
def api_delete_topic(topic_id):
    topics = load_topics()
    
    if topic_id not in topics:
        return jsonify({'error': '主题不存在'}), 404
    
    del topics[topic_id]
    save_topics(topics)
    
    return jsonify({'success': True})

@app.route('/api/tags')
def api_tags():
    posts = load_posts()
    
    tag_counts = {}
    for post in posts.values():
        for tag in post.get('tags', []):
            tag_counts[tag] = tag_counts.get(tag, 0) + 1
    
    tags = sorted(tag_counts.items(), key=lambda x: x[1], reverse=True)
    return jsonify([{'name': t[0], 'count': t[1]} for t in tags[:20]])

if __name__ == '__main__':
    print("=" * 50)
    print("技术论坛 - 后台管理系统")
    print("=" * 50)
    print(f"访问地址: http://localhost:19005")
    print("=" * 50)
    
    app.run(host='0.0.0.0', port=19005, debug=True)