// 全局变量
let customCards = [];
let currentSortType = 'newest';
let currentFilterType = 'all';
let currentUserId = null;
let currentCardId = null;
let userVotes = {};

// DOM元素
const cardsContainer = document.getElementById('cards-container');
const sortBySelect = document.getElementById('sort-by');
const filterBySelect = document.getElementById('filter-by');
const cardModal = document.getElementById('card-modal');
const closeModal = document.querySelector('.close-modal');
const upvoteBtn = document.getElementById('upvote-btn');
const downvoteBtn = document.getElementById('downvote-btn');

// 页面加载完成后初始化
document.addEventListener('DOMContentLoaded', () => {
    // 获取当前用户ID
    getCurrentUser()
        .then(userId => {
            currentUserId = userId;
            // 获取用户投票历史
            return getUserVotes(userId);
        })
        .then(votes => {
            userVotes = votes;
            // 加载自定义卡牌
            loadCustomCards();
        })
        .catch(error => {
            console.error('初始化失败:', error);
            showErrorMessage('加载数据失败，请刷新页面重试');
        });
    
    // 添加事件监听器
    sortBySelect.addEventListener('change', () => {
        currentSortType = sortBySelect.value;
        renderCards();
    });
    
    filterBySelect.addEventListener('change', () => {
        currentFilterType = filterBySelect.value;
        renderCards();
    });
    
    // 关闭模态框
    closeModal.addEventListener('click', () => {
        cardModal.style.display = 'none';
    });
    
    // 点击模态框外部关闭
    window.addEventListener('click', (event) => {
        if (event.target === cardModal) {
            cardModal.style.display = 'none';
        }
    });
    
    // 投票按钮点击事件
    upvoteBtn.addEventListener('click', () => {
        if (currentCardId) {
            voteCard(currentCardId, 'upvote');
        }
    });
    
    downvoteBtn.addEventListener('click', () => {
        if (currentCardId) {
            voteCard(currentCardId, 'downvote');
        }
    });
});

// 获取当前用户ID
async function getCurrentUser() {
    try {
        const response = await fetch('/api/current_user');
        if (!response.ok) {
            throw new Error('获取用户信息失败');
        }
        
        const data = await response.json();
        return data.user_id;
    } catch (error) {
        console.error('获取用户ID失败:', error);
        return null;
    }
}

// 获取用户投票历史
async function getUserVotes(userId) {
    if (!userId) return {};
    
    try {
        const response = await fetch(`/api/user_votes`);
        if (!response.ok) {
            throw new Error('获取投票历史失败');
        }
        
        const data = await response.json();
        return data.votes || {};
    } catch (error) {
        console.error('获取投票历史失败:', error);
        return {};
    }
}

// 加载自定义卡牌
async function loadCustomCards() {
    cardsContainer.innerHTML = '<div class="loading-indicator">加载中...</div>';
    
    try {
        const response = await fetch('/api/custom_cards');
        if (!response.ok) {
            throw new Error('加载卡牌失败');
        }
        
        const data = await response.json();
        customCards = data.cards || [];
        
        // 渲染卡牌
        renderCards();
    } catch (error) {
        console.error('加载卡牌失败:', error);
        cardsContainer.innerHTML = `<div class="error-message">加载卡牌失败: ${error.message}</div>`;
    }
}

// 渲染卡牌列表
function renderCards() {
    if (!customCards || customCards.length === 0) {
        cardsContainer.innerHTML = `
            <div class="empty-state">
                <h2>暂无卡牌</h2>
                <p>成为第一个创建自制卡牌的人吧！</p>
                <a href="/create_card" class="btn btn-primary">创建卡牌</a>
            </div>
        `;
        return;
    }
    
    // 过滤卡牌
    let filteredCards = [...customCards];
    
    if (currentFilterType === 'my' && currentUserId) {
        filteredCards = filteredCards.filter(card => card.creator_id === currentUserId);
        
        // 如果过滤后没有卡牌
        if (filteredCards.length === 0) {
            cardsContainer.innerHTML = `
                <div class="empty-state">
                    <h2>您还没有创建卡牌</h2>
                    <p>点击下方按钮开始创建您的第一张自制卡牌！</p>
                    <a href="/create_card" class="btn btn-primary">创建卡牌</a>
                </div>
            `;
            return;
        }
    }
    
    // 排序卡牌
    sortCards(filteredCards);
    
    // 渲染卡牌
    cardsContainer.innerHTML = filteredCards.map(card => {
        // 计算净投票数
        const voteScore = (card.upvotes || 0) - (card.downvotes || 0);
        const voteClass = voteScore > 0 ? 'vote-positive' : (voteScore < 0 ? 'vote-negative' : 'vote-neutral');
        
        // 格式化创建时间
        const createdDate = new Date(card.created_at);
        const formattedDate = `${createdDate.getFullYear()}-${(createdDate.getMonth() + 1).toString().padStart(2, '0')}-${createdDate.getDate().toString().padStart(2, '0')}`;
        
        return `
            <div class="card-item" data-id="${card.id}">
                <div class="card-header">
                    <div class="card-avatar">${card.character.avatar || '👤'}</div>
                    <div class="card-info">
                        <h3>${card.character.name}</h3>
                        <p>${card.character.title}</p>
                    </div>
                </div>
                <div class="card-content">
                    <h2 class="card-title">${card.title}</h2>
                    <p class="card-text">${card.description}</p>
                </div>
                <div class="card-footer">
                    <div class="card-creator">
                        由 ${card.creator_name} 创建于 ${formattedDate}
                    </div>
                    <div class="card-votes ${voteClass}">
                        <span class="vote-count">${voteScore}</span>
                    </div>
                </div>
            </div>
        `;
    }).join('');
    
    // 添加卡牌点击事件
    document.querySelectorAll('.card-item').forEach(card => {
        card.addEventListener('click', () => {
            const cardId = card.getAttribute('data-id');
            openCardDetails(cardId);
        });
    });
}

// 排序卡牌
function sortCards(cards) {
    switch (currentSortType) {
        case 'newest':
            // 按创建时间降序排序（最新的在前面）
            cards.sort((a, b) => new Date(b.created_at) - new Date(a.created_at));
            break;
        case 'popular':
            // 按点赞数降序排序
            cards.sort((a, b) => ((b.upvotes || 0) - (b.downvotes || 0)) - ((a.upvotes || 0) - (a.downvotes || 0)));
            break;
        case 'controversial':
            // 按总投票数排序 (争议性)
            cards.sort((a, b) => ((b.upvotes || 0) + (b.downvotes || 0)) - ((a.upvotes || 0) + (a.downvotes || 0)));
            break;
        default:
            // 默认按最新排序
            cards.sort((a, b) => new Date(b.created_at) - new Date(a.created_at));
    }
}

// 打开卡牌详情
function openCardDetails(cardId) {
    const card = customCards.find(c => c.id === cardId);
    if (!card) return;
    
    // 更新当前卡牌ID
    currentCardId = cardId;
    
    // 填充模态框内容
    document.getElementById('modal-card-title').textContent = card.title;
    document.getElementById('modal-card-creator').textContent = card.creator_name;
    
    // 格式化创建时间
    const createdDate = new Date(card.created_at);
    const formattedDate = `${createdDate.getFullYear()}-${(createdDate.getMonth() + 1).toString().padStart(2, '0')}-${createdDate.getDate().toString().padStart(2, '0')}`;
    document.getElementById('modal-card-date').textContent = formattedDate;
    
    document.getElementById('modal-card-description').textContent = card.description;
    document.getElementById('modal-option-a-text').textContent = card.option_a.text;
    document.getElementById('modal-option-b-text').textContent = card.option_b.text;
    
    // 生成效果标签
    const optionAEffects = document.getElementById('modal-option-a-effects');
    const optionBEffects = document.getElementById('modal-option-b-effects');
    
    optionAEffects.innerHTML = generateEffectTags(card.option_a.effects);
    optionBEffects.innerHTML = generateEffectTags(card.option_b.effects);
    
    // 更新投票状态
    const voteScore = (card.upvotes || 0) - (card.downvotes || 0);
    document.getElementById('modal-card-votes').textContent = voteScore;
    
    // 检查用户之前的投票
    const userVote = userVotes[cardId];
    upvoteBtn.classList.toggle('voted', userVote === 'upvote');
    downvoteBtn.classList.toggle('voted', userVote === 'downvote');
    
    // 显示模态框
    cardModal.style.display = 'block';
}

// 生成效果标签HTML
function generateEffectTags(effects) {
    if (!effects) return '';
    
    const tags = [];
    for (const [stat, value] of Object.entries(effects)) {
        if (value === 0) continue;
        
        let statName = '';
        let statIcon = '';
        
        switch (stat) {
            case 'loyalty':
                statName = '帝国忠诚度';
                statIcon = '🦅';
                break;
            case 'chaos':
                statName = '混沌侵染';
                statIcon = '🌀';
                break;
            case 'population':
                statName = '民众控制';
                statIcon = '👥';
                break;
            case 'military':
                statName = '军事力量';
                statIcon = '🔫';
                break;
            case 'resources':
                statName = '资源储备';
                statIcon = '⚙️';
                break;
        }
        
        const isPositive = value > 0;
        tags.push(`
            <div class="effect-tag ${isPositive ? 'positive' : 'negative'}">
                ${statIcon} ${statName} ${isPositive ? '+' : ''}${value}
            </div>
        `);
    }
    
    return tags.join('');
}

// 投票
async function voteCard(cardId, voteType) {
    if (!currentUserId) {
        showMessage('请先登录后再投票');
        return;
    }
    
    try {
        const response = await fetch(`/api/vote_card`, {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify({
                card_id: cardId,
                vote_type: voteType
            })
        });
        
        if (!response.ok) {
            throw new Error('投票失败');
        }
        
        const data = await response.json();
        
        // 更新本地投票记录
        userVotes[cardId] = data.newVote || null;
        
        // 更新卡牌数据
        const cardIndex = customCards.findIndex(c => c.id === cardId);
        if (cardIndex !== -1) {
            customCards[cardIndex].upvotes = data.upvotes;
            customCards[cardIndex].downvotes = data.downvotes;
            
            // 更新UI
            const voteScore = data.upvotes - data.downvotes;
            document.getElementById('modal-card-votes').textContent = voteScore;
            
            // 更新投票按钮状态
            upvoteBtn.classList.toggle('voted', data.newVote === 'upvote');
            downvoteBtn.classList.toggle('voted', data.newVote === 'downvote');
            
            // 渲染卡牌列表以更新投票数量
            renderCards();
        }
    } catch (error) {
        console.error('投票失败:', error);
        showMessage('投票失败，请稍后再试');
    }
}

// 显示错误消息
function showErrorMessage(message) {
    cardsContainer.innerHTML = `<div class="error-message">${message}</div>`;
}

// 显示消息（临时弹出提示）
function showMessage(message) {
    const messageElement = document.createElement('div');
    messageElement.className = 'message-popup';
    messageElement.textContent = message;
    
    document.body.appendChild(messageElement);
    
    // 消息显示动画
    setTimeout(() => {
        messageElement.classList.add('show');
    }, 10);
    
    // 3秒后移除消息
    setTimeout(() => {
        messageElement.classList.remove('show');
        setTimeout(() => {
            messageElement.remove();
        }, 300);
    }, 3000);
}