import request from './request'
import type { ApiResponse } from '@/types/api'
import { getToken } from '@/utils/token'

/** Token 相关辅助 —— 旧版 api.js 中 handleUnauthorized 行为已由 request.ts 拦截器接管 */

function authHeaders(): Record<string, string> {
  const token = getToken()
  return token ? { Authorization: `Bearer ${token}` } : {}
}

// ==================== 文档 CRUD ====================

/** 文档列表（分页 + 过滤 + 搜索） */
export function listDocuments(page = 1, size = 10, categoryId?: string, status?: string, keyword?: string, tag?: string, folderId?: string, sortField?: string, sortOrder?: string): Promise<ApiResponse> {
  let path = `/document/list?page=${page}&size=${size}`
  if (categoryId) path += `&categoryId=${categoryId}`
  if (folderId != null) path += `&folderId=${folderId}`
  if (status) path += `&status=${status}`
  if (keyword) path += `&keyword=${encodeURIComponent(keyword)}`
  if (tag) path += `&tag=${encodeURIComponent(tag)}`
  if (sortField) path += `&sortField=${sortField}`
  if (sortOrder) path += `&sortOrder=${sortOrder}`
  return request.get(path).then(r => r.data)
}

/** 文档详情 */
export function getDocumentDetail(id: string): Promise<ApiResponse> {
  return request.get(`/document/${id}`).then(r => r.data)
}

/** 文档分块列表 */
export function getDocumentChunks(id: string): Promise<ApiResponse> {
  return request.get(`/document/${id}/chunks`).then(r => r.data)
}

/** 下载文档原始文件 */
export async function downloadDocument(id: string): Promise<void> {
  const response = await fetch(`/document/download/${id}`, { headers: authHeaders() })
  if (!response.ok) {
    const error = await response.json().catch(() => ({ message: '下载失败' }))
    throw new Error(error.message || `HTTP ${response.status}`)
  }
  const disposition = response.headers.get('Content-Disposition')
  let filename = 'download'
  if (disposition) {
    const utf8Match = disposition.match(/filename\*=UTF-8''(.+?)(?:;|$)/i)
    if (utf8Match) {
      filename = decodeURIComponent(utf8Match[1])
    } else {
      const quotedMatch = disposition.match(/filename="(.+?)"/i)
      if (quotedMatch) filename = decodeURIComponent(quotedMatch[1])
    }
  }
  const blob = await response.blob()
  const url = window.URL.createObjectURL(blob)
  const a = document.createElement('a')
  a.href = url
  a.download = filename
  document.body.appendChild(a)
  a.click()
  document.body.removeChild(a)
  window.URL.revokeObjectURL(url)
}

/** 删除文档 */
export function deleteDocument(id: string): Promise<ApiResponse> {
  return request.delete(`/document/${id}`).then(r => r.data)
}

/** 更新文档元信息 */
export function updateDocument(id: string, title: string, categoryId: string, tags?: string[]): Promise<ApiResponse> {
  return request.put(`/document/${id}`, { title, categoryId, tags }).then(r => r.data)
}

/** 重新处理文档 */
export function reprocessDocument(id: string): Promise<ApiResponse> {
  return request.put(`/document/${id}/reprocess`).then(r => r.data)
}

/** 批量删除文档 */
export function batchDeleteDocuments(ids: string[]): Promise<ApiResponse> {
  return request.post('/document/batch/delete', { ids }).then(r => r.data)
}

/** 批量重新处理文档 */
export function batchReprocessDocuments(ids: string[]): Promise<ApiResponse> {
  return request.post('/document/batch/reprocess', { ids }).then(r => r.data)
}

/** 切换文档启用/禁用 */
export function toggleDocument(id: string): Promise<ApiResponse> {
  return request.put(`/document/${id}/toggle`).then(r => r.data)
}

/** 批量启用/禁用 */
export function batchToggleDocuments(ids: string[], enabled: boolean): Promise<ApiResponse> {
  return request.post('/document/batch/toggle', { ids, enabled }).then(r => r.data)
}

/** 批量移动（分类根或目录，folderId 为空/0 表示移动到分类根） */
export function batchMoveDocuments(ids: string[], categoryId: string, folderId?: string): Promise<ApiResponse> {
  return request.post('/document/batch/move', { ids, categoryId, folderId }).then(r => r.data)
}

/** 更新单个分块内容 */
export function updateChunk(docId: string, chunkIndex: number, content: string): Promise<ApiResponse> {
  return request.put(`/document/${docId}/chunk/${chunkIndex}`, { content }).then(r => r.data)
}

/** 删除单个分块 */
export function deleteChunk(docId: string, chunkIndex: number): Promise<ApiResponse> {
  return request.delete(`/document/${docId}/chunk/${chunkIndex}`).then(r => r.data)
}

/** 语义搜索 */
export function searchDocuments(query: string, topK?: number, similarityThreshold?: number, categoryId?: string, categoryIds?: string[], searchMode?: string): Promise<ApiResponse> {
  const body: any = { query, topK, similarityThreshold }
  if (categoryIds && categoryIds.length) body.categoryIds = categoryIds
  if (categoryId) body.categoryId = categoryId
  if (searchMode) body.searchMode = searchMode
  return request.post('/document/search', body).then(r => r.data)
}

// ==================== 统计 ====================

/** 知识库统计 */
export function getStats(): Promise<ApiResponse> {
  return request.get('/document/stats').then(r => r.data)
}

// ==================== 标签 ====================

/** 获取标签列表 */
export function getTagList(): Promise<ApiResponse> {
  return request.get('/tag/list').then(r => r.data)
}