import { useState, useEffect, useCallback } from 'react';
import knowledgeService from '@/services/knowledge_service';
import type { IKnowledge, IKnowledgeResult } from '@/interfaces/database/knowledge';
import type { IFetchKnowledgeListRequestParams } from '@/interfaces/request/knowledge';

// 知识库列表Hook状态接口
export interface UseKnowledgeListState {
  knowledgeBases: IKnowledge[];
  total: number;
  loading: boolean;
  error: string | null;
  currentPage: number;
  pageSize: number;
  keywords: string;
}

// 知识库列表Hook返回值接口
export interface UseKnowledgeListReturn extends UseKnowledgeListState {
  fetchKnowledgeBases: (params?: IFetchKnowledgeListRequestParams) => Promise<void>;
  setKeywords: (keywords: string) => void;
  setCurrentPage: (page: number) => void;
  setPageSize: (size: number) => void;
  refresh: () => Promise<void>;
}

/**
 * 知识库列表数据管理Hook
 * 支持关键词搜索、分页等功能
 */
export const useKnowledgeList = (
  initialParams?: IFetchKnowledgeListRequestParams
): UseKnowledgeListReturn => {
  const [knowledgeBases, setKnowledgeBases] = useState<IKnowledge[]>([]);
  const [total, setTotal] = useState(0);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [currentPage, setCurrentPage] = useState(initialParams?.page || 1);
  const [pageSize, setPageSize] = useState(initialParams?.page_size || 10);
  const [keywords, setKeywords] = useState(initialParams?.keywords || '');

  /**
   * 获取知识库列表
   */
  const fetchKnowledgeBases = useCallback(async (params?: IFetchKnowledgeListRequestParams) => {
    try {
      setLoading(true);
      setError(null);

      // 合并参数
      const queryParams = {
        keywords: params?.keywords ?? keywords,
        page: params?.page ?? currentPage,
        page_size: params?.page_size ?? pageSize,
      };

      // 构建请求体
      const requestBody: any = {};
      if (queryParams.keywords && queryParams.keywords.trim()) {
        requestBody.keywords = queryParams.keywords.trim();
      }

      // 构建查询参数
      const requestParams: any = {};
      if (queryParams.page) {
        requestParams.page = queryParams.page;
      }
      if (queryParams.page_size) {
        requestParams.page_size = queryParams.page_size;
      }
      if (queryParams.keywords) {
        requestParams.keywords = queryParams.keywords;
      }

      const response = await knowledgeService.getKnowledgeList(
        Object.keys(requestParams).length > 0 ? requestParams : undefined,
        Object.keys(requestBody).length > 0 ? requestBody : undefined
      );

      // 检查响应状态
      if (response.data.code === 0) {
        const data = response.data.data as IKnowledgeResult;
        setKnowledgeBases(data.kbs || []);
        setTotal(data.total || 0);
      } else {
        throw new Error(response.data.message || '获取知识库列表失败');
      }
    } catch (err: any) {
      const errorMessage = err.response?.data?.message || err.message || '获取知识库列表失败';
      setError(errorMessage);
      console.error('Failed to fetch knowledge bases:', err);
    } finally {
      setLoading(false);
    }
  }, [keywords, currentPage, pageSize]);

  /**
   * 刷新当前页面数据
   */
  const refresh = useCallback(() => {
    return fetchKnowledgeBases();
  }, [fetchKnowledgeBases]);

  /**
   * 设置关键词并重置到第一页
   */
  const handleSetKeywords = useCallback((newKeywords: string) => {
    setKeywords(newKeywords);
    setCurrentPage(1);
  }, []);

  /**
   * 设置当前页
   */
  const handleSetCurrentPage = useCallback((page: number) => {
    setCurrentPage(page);
  }, []);

  /**
   * 设置页面大小并重置到第一页
   */
  const handleSetPageSize = useCallback((size: number) => {
    setPageSize(size);
    setCurrentPage(1);
  }, []);

  // 当关键词、页码或页面大小变化时重新获取数据
  useEffect(() => {
    fetchKnowledgeBases();
  }, [keywords, currentPage, pageSize]);

  return {
    knowledgeBases,
    total,
    loading,
    error,
    currentPage,
    pageSize,
    keywords,
    fetchKnowledgeBases,
    setKeywords: handleSetKeywords,
    setCurrentPage: handleSetCurrentPage,
    setPageSize: handleSetPageSize,
    refresh,
  };
};

/**
 * 知识库详情Hook
 */
export const useKnowledgeDetail = (kbId: string) => {
  const [knowledge, setKnowledge] = useState<IKnowledge | null>(null);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);

  const fetchKnowledgeDetail = useCallback(async () => {
    if (!kbId) return;

    try {
      setLoading(true);
      setError(null);

      const response = await knowledgeService.getKnowledgeDetail({ kb_id: kbId });

      if (response.data.code === 0) {
        setKnowledge(response.data.data);
      } else {
        throw new Error(response.data.message || '获取知识库详情失败');
      }
    } catch (err: any) {
      const errorMessage = err.response?.data?.message || err.message || '获取知识库详情失败';
      setError(errorMessage);
      console.error('Failed to fetch knowledge detail:', err);
    } finally {
      setLoading(false);
    }
  }, [kbId]);

  useEffect(() => {
    fetchKnowledgeDetail();
  }, [fetchKnowledgeDetail]);

  return {
    knowledge,
    loading,
    error,
    refresh: fetchKnowledgeDetail,
  };
};

/**
 * 知识库操作Hook
 * 提供创建、更新、删除知识库的功能
 */
export const useKnowledgeOperations = () => {
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);

  /**
   * 创建知识库
   */
  const createKnowledge = useCallback(async (data: Partial<IKnowledge>) => {
    try {
      setLoading(true);
      setError(null);

      const response = await knowledgeService.createKnowledge(data);

      if (response.data.code === 0) {
        return response.data.data;
      } else {
        throw new Error(response.data.message || '创建知识库失败');
      }
    } catch (err: any) {
      const errorMessage = err.response?.data?.message || err.message || '创建知识库失败';
      setError(errorMessage);
      console.error('Failed to create knowledge:', err);
      throw err;
    } finally {
      setLoading(false);
    }
  }, []);

  /**
   * 更新知识库基础信息
   * 包括名称、描述、语言等基本信息
   */
  const updateKnowledgeBasicInfo = useCallback(async (data: {
    id: string;
    name?: string;
    description?: string;
    language?: string;
    avatar?: any;
    permission?: string;
  }) => {
    try {
      setLoading(true);
      setError(null);

      const updateData = {
        kb_id: data.id,
        ...data,
      };

      const response = await knowledgeService.updateKnowledge(updateData);

      if (response.data.code === 0) {
        return response.data.data;
      } else {
        throw new Error(response.data.message || '更新知识库基础信息失败');
      }
    } catch (err: any) {
      const errorMessage = err.response?.data?.message || err.message || '更新知识库基础信息失败';
      setError(errorMessage);
      console.error('Failed to update knowledge basic info:', err);
      throw err;
    } finally {
      setLoading(false);
    }
  }, []);

  /**
   * 更新知识库模型配置
   * 包括嵌入模型、解析器配置、相似度阈值等
   */
  const updateKnowledgeModelConfig = useCallback(async (data: {
    id: string;
    embd_id?: string;
    // parser_config?: Partial<ParserConfig>;
    similarity_threshold?: number;
    vector_similarity_weight?: number;
    parser_id?: string;
  }) => {
    try {
      setLoading(true);
      setError(null);

      const updateData = {
        kb_id: data.id,
        ...data,
      };

      const response = await knowledgeService.updateKnowledge(updateData);

      if (response.data.code === 0) {
        return response.data.data;
      } else {
        throw new Error(response.data.message || '更新知识库模型配置失败');
      }
    } catch (err: any) {
      const errorMessage = err.response?.data?.message || err.message || '更新知识库模型配置失败';
      setError(errorMessage);
      console.error('Failed to update knowledge model config:', err);
      throw err;
    } finally {
      setLoading(false);
    }
  }, []);

  /**
   * 删除知识库
   */
  const deleteKnowledge = useCallback(async (kbId: string) => {
    try {
      setLoading(true);
      setError(null);

      const response = await knowledgeService.removeKnowledge({ kb_id: kbId });

      if (response.data.code === 0) {
        return response.data.data;
      } else {
        throw new Error(response.data.message || '删除知识库失败');
      }
    } catch (err: any) {
      const errorMessage = err.response?.data?.message || err.message || '删除知识库失败';
      setError(errorMessage);
      console.error('Failed to delete knowledge:', err);
      throw err;
    } finally {
      setLoading(false);
    }
  }, []);

  /**
   * 清除错误状态
   */
  const clearError = useCallback(() => {
    setError(null);
  }, []);

  return {
    loading,
    error,
    createKnowledge,
    updateKnowledgeBasicInfo,
    updateKnowledgeModelConfig,
    deleteKnowledge,
    clearError,
  };
};

/**
 * 知识库批量操作Hook
 * 提供批量删除等功能
 */
export const useKnowledgeBatchOperations = () => {
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);

  /**
   * 批量删除知识库
   */
  const batchDeleteKnowledge = useCallback(async (kbIds: string[]) => {
    try {
      setLoading(true);
      setError(null);

      const results = await Promise.allSettled(
        kbIds.map(kbId => knowledgeService.removeKnowledge({ kb_id: kbId }))
      );

      const failures = results
        .map((result, index) => ({ result, index }))
        .filter(({ result }) => result.status === 'rejected')
        .map(({ index }) => kbIds[index]);

      if (failures.length > 0) {
        throw new Error(`删除失败的知识库: ${failures.join(', ')}`);
      }

      return results;
    } catch (err: any) {
      const errorMessage = err.response?.data?.message || err.message || '批量删除知识库失败';
      setError(errorMessage);
      console.error('Failed to batch delete knowledge:', err);
      throw err;
    } finally {
      setLoading(false);
    }
  }, []);

  /**
   * 清除错误状态
   */
  const clearError = useCallback(() => {
    setError(null);
  }, []);

  return {
    loading,
    error,
    batchDeleteKnowledge,
    clearError,
  };
};