/**
 * LLM Index RAG - 前端交互脚本
 */

// 搜索表单处理
document.getElementById('searchForm')?.addEventListener('submit', async function(e) {
    e.preventDefault();
    
    const query = document.getElementById('queryInput').value.trim();
    const mode = document.querySelector('input[name="mode"]:checked').value;
    
    if (!query) {
        alert('请输入查询内容');
        return;
    }
    
    // 显示加载状态
    const resultsSection = document.getElementById('resultsSection');
    const ragSection = document.getElementById('ragSection');
    const resultsContainer = document.getElementById('resultsContainer');
    const ragAnswer = document.getElementById('ragAnswer');
    const ragSources = document.getElementById('ragSources');
    const resultCount = document.getElementById('resultCount');
    
    resultsSection.style.display = 'none';
    ragSection.style.display = 'none';
    resultsContainer.innerHTML = '<div class="text-center py-4"><div class="spinner-border text-primary"></div><p class="mt-2">正在检索...</p></div>';
    resultsSection.style.display = 'block';
    
    try {
        if (mode === 'search') {
            // 文档检索模式
            const response = await fetch('/api/search', {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify({query: query, top_k: 10})
            });
            
            const data = await response.json();
            
            if (data.error) {
                resultsContainer.innerHTML = `<div class="alert alert-danger">${data.error}</div>`;
                return;
            }
            
            resultCount.textContent = data.total;
            
            if (data.results && data.results.length > 0) {
                resultsContainer.innerHTML = data.results.map(r => `
                    <div class="result-item">
                        <h6 class="mb-1">
                            <a href="/documents" class="text-decoration-none">${r.title || r.document_title || '文档'}</a>
                        </h6>
                        <p class="text-muted small mb-1">${r.summary || r.content?.substring(0, 200) + '...' || ''}</p>
                        <div class="d-flex gap-2 align-items-center">
                            <span class="source-tag">${r.source || '本地文档'}</span>
                            <span class="badge bg-primary">${(r.score * 100).toFixed(1)}%</span>
                        </div>
                    </div>
                `).join('');
            } else {
                resultsContainer.innerHTML = `
                    <div class="text-center py-4 text-muted">
                        <i class="bi bi-search display-4"></i>
                        <p class="mt-2">未找到相关结果</p>
                        <p class="small">请尝试其他关键词，或先上传并索引文档</p>
                    </div>
                `;
            }
        } else {
            // RAG问答模式
            resultsContainer.innerHTML = '<div class="text-center py-4"><div class="spinner-border text-primary"></div><p class="mt-2">正在生成回答...</p></div>';
            
            const response = await fetch('/api/rag/answer', {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify({query: query, top_k: 5})
            });
            
            const data = await response.json();
            
            if (data.error) {
                resultsContainer.innerHTML = `<div class="alert alert-danger">${data.error}</div>`;
                return;
            }
            
            resultsSection.style.display = 'none';
            ragSection.style.display = 'block';
            
            // 显示回答
            ragAnswer.innerHTML = `
                <div class="d-flex align-items-start gap-3">
                    <div class="bg-primary text-white rounded-circle p-2">
                        <i class="bi bi-robot"></i>
                    </div>
                    <div class="flex-grow-1">
                        <div class="markdown-content">${data.answer || '抱歉，无法生成回答。'}</div>
                    </div>
                </div>
            `;
            
            // 显示来源
            if (data.sources && data.sources.length > 0) {
                ragSources.innerHTML = data.sources.map(s => `
                    <div class="result-item">
                        <h6 class="mb-1">${s.title || s.document_title || '参考文档'}</h6>
                        <p class="text-muted small mb-0">${s.content?.substring(0, 150) + '...' || ''}</p>
                    </div>
                `).join('');
            } else {
                ragSources.innerHTML = '<p class="text-muted">无参考来源</p>';
            }
        }
    } catch (err) {
        resultsContainer.innerHTML = `<div class="alert alert-danger">请求失败: ${err.message}</div>`;
    }
});

// 文档上传
document.getElementById('uploadForm')?.addEventListener('submit', async function(e) {
    e.preventDefault();
    
    const formData = new FormData(this);
    const fileInput = document.getElementById('fileInput');
    
    if (!fileInput.files.length) {
        alert('请选择文件');
        return;
    }
    
    const uploadBtn = document.getElementById('uploadBtn');
    uploadBtn.disabled = true;
    uploadBtn.innerHTML = '<span class="spinner-border spinner-border-sm"></span> 上传中...';
    
    try {
        const response = await fetch('/api/documents', {
            method: 'POST',
            body: formData
        });
        
        const data = await response.json();
        
        if (data.success) {
            alert('上传成功！');
            location.reload();
        } else {
            alert('上传失败: ' + (data.error || '未知错误'));
        }
    } catch (err) {
        alert('上传失败: ' + err.message);
    } finally {
        uploadBtn.disabled = false;
        uploadBtn.innerHTML = '<i class="bi bi-upload"></i> 上传';
    }
});

// 索引文档
async function indexDocument(docId) {
    if (!confirm('确定要索引此文档吗？这可能需要一些时间。')) return;
    
    try {
        const response = await fetch(`/api/index/${docId}`, {method: 'POST'});
        const data = await response.json();
        
        if (data.success) {
            alert('索引完成！');
            location.reload();
        } else {
            alert('索引失败: ' + (data.error || '未知错误'));
        }
    } catch (err) {
        alert('索引失败: ' + err.message);
    }
}

// 删除文档
async function deleteDocument(docId) {
    if (!confirm('确定要删除此文档吗？此操作不可恢复。')) return;
    
    try {
        const response = await fetch(`/api/documents/${docId}`, {method: 'DELETE'});
        const data = await response.json();
        
        if (data.success) {
            alert('删除成功！');
            location.reload();
        } else {
            alert('删除失败: ' + (data.error || '未知错误'));
        }
    } catch (err) {
        alert('删除失败: ' + err.message);
    }
}

// 批量索引
async function batchIndex() {
    if (!confirm('确定要索引所有待处理文档吗？')) return;
    
    try {
        const response = await fetch('/api/index/batch', {method: 'POST'});
        const data = await response.json();
        
        alert(`索引完成！成功: ${data.success}, 失败: ${data.failed}`);
        location.reload();
    } catch (err) {
        alert('批量索引失败: ' + err.message);
    }
}

// 重建索引
async function rebuildIndex() {
    if (!confirm('重建索引将清除所有现有索引，确定继续吗？')) return;
    
    try {
        const response = await fetch('/api/index/rebuild', {method: 'POST'});
        const data = await response.json();
        
        alert(`重建完成！成功: ${data.success}, 失败: ${data.failed}`);
        location.reload();
    } catch (err) {
        alert('重建索引失败: ' + err.message);
    }
}

// 加载统计信息
async function loadStats() {
    try {
        const response = await fetch('/api/stats');
        const stats = await response.json();
        
        document.getElementById('statDocs').textContent = stats.total_documents || 0;
        document.getElementById('statChunks').textContent = stats.total_chunks || 0;
        document.getElementById('statTerms').textContent = stats.total_terms || 0;
        document.getElementById('statWords').textContent = (stats.total_words || 0).toLocaleString();
    } catch (err) {
        console.error('加载统计失败:', err);
    }
}

// 页面加载时刷新统计
document.addEventListener('DOMContentLoaded', function() {
    // 如果在首页，定时刷新统计
    if (document.getElementById('statDocs')) {
        loadStats();
        setInterval(loadStats, 30000); // 每30秒刷新
    }
});