import { apiFetch, apiFetchForm } from "@/lib/api";

/**
 * 知识库（/api/knowledge/*）适配层。
 * 权限：后端 require_knowledge_operator —— 仅管理员或运营角色，前端不做二次判断。
 */

export interface KnowledgeDocument {
  doc_id?: string;
  id?: string;
  title?: string | null;
  filename?: string | null;
  collection_name?: string | null;
  chunk_count?: number | null;
  strategy?: string | null;
  create_time?: string | null;
  [key: string]: unknown;
}

export interface UploadPreview {
  filename?: string;
  strategy?: string;
  chunk_size?: number;
  chunk_overlap?: number;
  chunks?: unknown[];
  preview?: unknown;
  [key: string]: unknown;
}

export const knowledgeApi = {
  list: () => apiFetch<KnowledgeDocument[]>("/knowledge/documents"),

  get: (docId: string) =>
    apiFetch<KnowledgeDocument>(`/knowledge/documents/${encodeURIComponent(docId)}`),

  /** 第一步：上传文件拿切分预览，不落库。 */
  preview: (form: FormData) =>
    apiFetchForm<UploadPreview>("/knowledge/documents/preview", form),

  /** 第二步：确认入库（可复用 preview 返回的 doc_id）。 */
  confirm: (form: FormData) =>
    apiFetchForm<KnowledgeDocument>("/knowledge/documents/confirm", form),

  remove: (docId: string) =>
    apiFetch<{ doc_id?: string; deleted?: boolean; [key: string]: unknown }>(
      `/knowledge/documents/${encodeURIComponent(docId)}`,
      { method: "DELETE" }
    ),
};

/** 组装知识库上传表单，空值不提交，避免后端把空串当成有效参数。 */
export function buildKnowledgeForm(
  file: File,
  extra: {
    title?: string;
    doc_id?: string;
    collection_name?: string;
    strategy?: string;
    chunk_size?: number | null;
    chunk_overlap?: number | null;
  } = {}
): FormData {
  const form = new FormData();
  form.append("file", file);
  for (const [key, value] of Object.entries(extra)) {
    if (value !== undefined && value !== null && value !== "") {
      form.append(key, String(value));
    }
  }
  return form;
}