import { Injectable } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { ConversationContext } from '../claude-agent.service';
import { KnowledgeClientService } from '../../knowledge/knowledge-client.service';

export interface Tool {
  name: string;
  description: string;
  input_schema: {
    type: string;
    properties: Record<string, unknown>;
    required?: string[];
  };
}

@Injectable()
export class ImmigrationToolsService {
  constructor(
    private knowledgeClient: KnowledgeClientService,
    private configService: ConfigService,
  ) {}

  /**
   * Get all available tools for the agent
   */
  getTools(): Tool[] {
    return [
      {
        name: 'search_knowledge',
        description: '搜索香港移民相关知识库，获取最新的政策信息和常见问题解答',
        input_schema: {
          type: 'object',
          properties: {
            query: {
              type: 'string',
              description: '搜索查询内容',
            },
            category: {
              type: 'string',
              enum: ['QMAS', 'GEP', 'IANG', 'TTPS', 'CIES', 'TECHTAS'],
              description: '移民类别代码（可选）',
            },
          },
          required: ['query'],
        },
      },
      {
        name: 'check_off_topic',
        description: '检查用户的问题是否与香港移民相关，用于判断是否需要拒绝回答',
        input_schema: {
          type: 'object',
          properties: {
            question: {
              type: 'string',
              description: '用户的问题',
            },
          },
          required: ['question'],
        },
      },
      {
        name: 'collect_assessment_info',
        description: '收集用户的个人信息用于移民资格评估',
        input_schema: {
          type: 'object',
          properties: {
            category: {
              type: 'string',
              enum: ['QMAS', 'GEP', 'IANG', 'TTPS', 'CIES', 'TECHTAS'],
              description: '用户感兴趣的移民类别',
            },
            age: {
              type: 'number',
              description: '用户年龄',
            },
            education: {
              type: 'string',
              description: '最高学历',
            },
            university: {
              type: 'string',
              description: '毕业院校',
            },
            yearsOfExperience: {
              type: 'number',
              description: '工作年限',
            },
            currentJobTitle: {
              type: 'string',
              description: '当前职位',
            },
            industry: {
              type: 'string',
              description: '所属行业',
            },
            annualIncome: {
              type: 'number',
              description: '年收入（人民币）',
            },
            hasHKEmployer: {
              type: 'boolean',
              description: '是否有香港雇主',
            },
          },
          required: ['category'],
        },
      },
      {
        name: 'generate_payment',
        description: '为付费评估服务生成支付二维码',
        input_schema: {
          type: 'object',
          properties: {
            serviceType: {
              type: 'string',
              enum: ['ASSESSMENT'],
              description: '服务类型',
            },
            category: {
              type: 'string',
              enum: ['QMAS', 'GEP', 'IANG', 'TTPS', 'CIES', 'TECHTAS'],
              description: '移民类别',
            },
            paymentMethod: {
              type: 'string',
              enum: ['ALIPAY', 'WECHAT', 'CREDIT_CARD'],
              description: '支付方式',
            },
          },
          required: ['serviceType', 'category', 'paymentMethod'],
        },
      },
      {
        name: 'save_user_memory',
        description: '保存用户的重要信息到长期记忆，以便后续对话中记住用户情况',
        input_schema: {
          type: 'object',
          properties: {
            memoryType: {
              type: 'string',
              enum: ['FACT', 'PREFERENCE', 'INTENT'],
              description: '记忆类型：FACT-用户陈述的事实，PREFERENCE-用户偏好，INTENT-用户意图',
            },
            content: {
              type: 'string',
              description: '要记住的内容',
            },
            category: {
              type: 'string',
              enum: ['QMAS', 'GEP', 'IANG', 'TTPS', 'CIES', 'TECHTAS'],
              description: '相关的移民类别（可选）',
            },
          },
          required: ['memoryType', 'content'],
        },
      },
      {
        name: 'get_user_context',
        description: '获取用户的历史背景信息和之前的对话记忆，帮助提供更个性化的建议',
        input_schema: {
          type: 'object',
          properties: {
            query: {
              type: 'string',
              description: '当前问题，用于检索相关记忆',
            },
          },
          required: ['query'],
        },
      },
      // ========== 实时工具 ==========
      {
        name: 'get_current_datetime',
        description: '获取当前的日期和时间，用于回答与时间相关的问题',
        input_schema: {
          type: 'object',
          properties: {
            timezone: {
              type: 'string',
              description: '时区，默认为 Asia/Hong_Kong',
            },
            format: {
              type: 'string',
              enum: ['full', 'date', 'time'],
              description: '返回格式：full-完整日期时间，date-仅日期，time-仅时间',
            },
          },
        },
      },
      {
        name: 'web_search',
        description: '搜索互联网获取最新信息，用于查询移民政策变更、新闻动态等实时内容',
        input_schema: {
          type: 'object',
          properties: {
            query: {
              type: 'string',
              description: '搜索关键词',
            },
            site: {
              type: 'string',
              description: '限定搜索网站，如 immd.gov.hk（香港入境处）',
            },
            language: {
              type: 'string',
              enum: ['zh-CN', 'zh-TW', 'en'],
              description: '搜索语言，默认 zh-CN',
            },
          },
          required: ['query'],
        },
      },
      {
        name: 'get_exchange_rate',
        description: '查询实时货币汇率，用于投资移民金额换算等场景',
        input_schema: {
          type: 'object',
          properties: {
            from: {
              type: 'string',
              description: '源货币代码，如 CNY（人民币）、USD（美元）',
            },
            to: {
              type: 'string',
              description: '目标货币代码，如 HKD（港币）',
            },
            amount: {
              type: 'number',
              description: '要转换的金额（可选）',
            },
          },
          required: ['from', 'to'],
        },
      },
      {
        name: 'fetch_immigration_news',
        description: '获取香港移民相关的最新新闻和政策公告',
        input_schema: {
          type: 'object',
          properties: {
            category: {
              type: 'string',
              enum: ['QMAS', 'GEP', 'IANG', 'TTPS', 'CIES', 'TECHTAS', 'ALL'],
              description: '移民类别，ALL表示所有类别',
            },
            limit: {
              type: 'number',
              description: '返回条数，默认5条',
            },
          },
        },
      },
    ];
  }

  /**
   * Execute a tool and return the result
   */
  async executeTool(
    toolName: string,
    input: Record<string, unknown>,
    context: ConversationContext,
  ): Promise<unknown> {
    console.log(`[Tool] Executing ${toolName} with input:`, JSON.stringify(input));

    switch (toolName) {
      case 'search_knowledge':
        return this.searchKnowledge(input, context);

      case 'check_off_topic':
        return this.checkOffTopic(input);

      case 'collect_assessment_info':
        return this.collectAssessmentInfo(input, context);

      case 'generate_payment':
        return this.generatePayment(input, context);

      case 'save_user_memory':
        return this.saveUserMemory(input, context);

      case 'get_user_context':
        return this.getUserContext(input, context);

      case 'get_current_datetime':
        return this.getCurrentDatetime(input);

      case 'web_search':
        return this.webSearch(input);

      case 'get_exchange_rate':
        return this.getExchangeRate(input);

      case 'fetch_immigration_news':
        return this.fetchImmigrationNews(input);

      default:
        return { error: `Unknown tool: ${toolName}` };
    }
  }

  /**
   * Search knowledge base - 调用 knowledge-service RAG API
   */
  private async searchKnowledge(
    input: Record<string, unknown>,
    context: ConversationContext,
  ): Promise<unknown> {
    const { query, category } = input as { query: string; category?: string };

    console.log(`[Tool:search_knowledge] Query: "${query}", Category: ${category || 'all'}`);

    // 调用 knowledge-service RAG API
    const result = await this.knowledgeClient.retrieveKnowledge({
      query,
      userId: context.userId,
      category,
      includeMemories: true,
      includeExperiences: true,
    });

    if (result && result.content) {
      return {
        success: true,
        content: result.content,
        sources: result.sources,
        userContext: result.userMemories,
        relatedExperiences: result.systemExperiences,
        message: `找到 ${result.sources?.length || 0} 条相关知识`,
      };
    }

    // 降级：返回基础响应
    return {
      success: false,
      content: null,
      message: '知识库暂无相关内容，请基于内置知识回答',
    };
  }

  /**
   * Check if question is off-topic - 调用 knowledge-service API
   */
  private async checkOffTopic(input: Record<string, unknown>): Promise<unknown> {
    const { question } = input as { question: string };

    console.log(`[Tool:check_off_topic] Checking: "${question}"`);

    // 调用 knowledge-service 离题检测 API
    const result = await this.knowledgeClient.checkOffTopic(question);

    if (result.isOffTopic) {
      return {
        isOffTopic: true,
        confidence: result.confidence,
        suggestion: result.reason || '这个问题似乎与香港移民无关。作为移民咨询顾问，我专注于香港各类移民政策的咨询。请问您有香港移民相关的问题吗？',
      };
    }

    return {
      isOffTopic: false,
      confidence: result.confidence,
      suggestion: null,
    };
  }

  /**
   * Collect assessment info - 收集评估信息并保存到记忆
   */
  private async collectAssessmentInfo(
    input: Record<string, unknown>,
    context: ConversationContext,
  ): Promise<unknown> {
    const info = input as {
      category: string;
      age?: number;
      education?: string;
      university?: string;
      yearsOfExperience?: number;
      currentJobTitle?: string;
      industry?: string;
      annualIncome?: number;
      hasHKEmployer?: boolean;
    };

    console.log(`[Tool:collect_assessment_info] User ${context.userId} - Category: ${info.category}`);

    // 保存收集到的信息到用户记忆
    const memoryContent = Object.entries(info)
      .filter(([, v]) => v !== undefined)
      .map(([k, v]) => `${k}: ${v}`)
      .join(', ');

    if (memoryContent) {
      await this.knowledgeClient.saveUserMemory({
        userId: context.userId,
        memoryType: 'FACT',
        content: `用户评估信息 - ${memoryContent}`,
        sourceConversationId: context.conversationId,
        relatedCategory: info.category,
        importance: 80,
      });
    }

    return {
      success: true,
      collectedInfo: info,
      message: '已记录您的信息。如需完整评估，请选择付费评估服务。',
      nextStep: 'payment',
    };
  }

  /**
   * Generate payment QR code
   */
  private async generatePayment(
    input: Record<string, unknown>,
    context: ConversationContext,
  ): Promise<unknown> {
    const { serviceType, category, paymentMethod } = input as {
      serviceType: string;
      category: string;
      paymentMethod: string;
    };

    console.log(
      `[Tool:generate_payment] User ${context.userId} - ${serviceType} for ${category} via ${paymentMethod}`,
    );

    // 记录用户付费意向
    await this.knowledgeClient.saveUserMemory({
      userId: context.userId,
      memoryType: 'INTENT',
      content: `用户希望购买${category}类别的${serviceType}服务，选择${paymentMethod}支付`,
      sourceConversationId: context.conversationId,
      relatedCategory: category,
      importance: 90,
    });

    // TODO: 调用 payment-service 生成实际支付
    const priceMap: Record<string, number> = {
      QMAS: 99,
      GEP: 99,
      IANG: 79,
      TTPS: 99,
      CIES: 199,
      TECHTAS: 99,
    };

    const price = priceMap[category] || 99;

    return {
      success: true,
      orderId: `ORD_${Date.now()}`,
      amount: price,
      currency: 'CNY',
      paymentMethod,
      qrCodeUrl: `https://placeholder-payment-qr.com/${paymentMethod.toLowerCase()}/${Date.now()}`,
      expiresAt: new Date(Date.now() + 30 * 60 * 1000).toISOString(),
      message: `请扫描二维码支付 ¥${price} 完成${category}类别的移民资格评估服务`,
    };
  }

  /**
   * Save user memory - 调用 knowledge-service Memory API
   */
  private async saveUserMemory(
    input: Record<string, unknown>,
    context: ConversationContext,
  ): Promise<unknown> {
    const { memoryType, content, category } = input as {
      memoryType: 'FACT' | 'PREFERENCE' | 'INTENT';
      content: string;
      category?: string;
    };

    console.log(
      `[Tool:save_user_memory] User ${context.userId} - Type: ${memoryType}, Content: "${content}"`,
    );

    // 调用 knowledge-service Memory API
    const memory = await this.knowledgeClient.saveUserMemory({
      userId: context.userId,
      memoryType,
      content,
      sourceConversationId: context.conversationId,
      relatedCategory: category,
      importance: memoryType === 'FACT' ? 70 : memoryType === 'INTENT' ? 80 : 60,
    });

    if (memory) {
      return {
        success: true,
        memoryId: memory.id,
        message: '已记住您的信息，下次对话时我会记得',
      };
    }

    return {
      success: false,
      message: '记忆保存失败，但不影响当前对话',
    };
  }

  /**
   * Get user context - 获取用户历史背景
   */
  private async getUserContext(
    input: Record<string, unknown>,
    context: ConversationContext,
  ): Promise<unknown> {
    const { query } = input as { query: string };

    console.log(`[Tool:get_user_context] User ${context.userId} - Query: "${query}"`);

    // 并行获取相关记忆和重要记忆
    const [relevantMemories, topMemories] = await Promise.all([
      this.knowledgeClient.searchUserMemories({
        userId: context.userId,
        query,
        limit: 3,
      }),
      this.knowledgeClient.getUserTopMemories(context.userId, 5),
    ]);

    const allMemories = [...relevantMemories];

    // 添加不重复的重要记忆
    for (const mem of topMemories) {
      if (!allMemories.find(m => m.id === mem.id)) {
        allMemories.push(mem);
      }
    }

    if (allMemories.length > 0) {
      return {
        success: true,
        memories: allMemories.map(m => ({
          type: m.memoryType,
          content: m.content,
          importance: m.importance,
        })),
        message: `找到 ${allMemories.length} 条用户背景信息`,
      };
    }

    return {
      success: true,
      memories: [],
      message: '这是新用户，暂无历史信息',
    };
  }

  // ========== 实时工具实现 ==========

  /**
   * Get current datetime - 获取当前日期时间
   */
  private getCurrentDatetime(input: Record<string, unknown>): unknown {
    const { timezone = 'Asia/Hong_Kong', format = 'full' } = input as {
      timezone?: string;
      format?: 'full' | 'date' | 'time';
    };

    console.log(`[Tool:get_current_datetime] Timezone: ${timezone}, Format: ${format}`);

    const now = new Date();
    const options: Intl.DateTimeFormatOptions = {
      timeZone: timezone,
    };

    let result: string;

    switch (format) {
      case 'date':
        options.year = 'numeric';
        options.month = 'long';
        options.day = 'numeric';
        options.weekday = 'long';
        result = now.toLocaleDateString('zh-CN', options);
        break;
      case 'time':
        options.hour = '2-digit';
        options.minute = '2-digit';
        options.second = '2-digit';
        options.hour12 = false;
        result = now.toLocaleTimeString('zh-CN', options);
        break;
      case 'full':
      default:
        options.year = 'numeric';
        options.month = 'long';
        options.day = 'numeric';
        options.weekday = 'long';
        options.hour = '2-digit';
        options.minute = '2-digit';
        options.second = '2-digit';
        options.hour12 = false;
        result = now.toLocaleString('zh-CN', options);
        break;
    }

    return {
      success: true,
      datetime: result,
      timezone,
      timestamp: now.toISOString(),
      message: `当前${timezone}时间: ${result}`,
    };
  }

  /**
   * Web search - 搜索互联网获取最新信息
   * 使用 Google Custom Search API 或其他搜索服务
   */
  private async webSearch(input: Record<string, unknown>): Promise<unknown> {
    const { query, site, language = 'zh-CN' } = input as {
      query: string;
      site?: string;
      language?: string;
    };

    console.log(`[Tool:web_search] Query: "${query}", Site: ${site || 'any'}, Language: ${language}`);

    // 构建搜索查询
    let searchQuery = query;
    if (site) {
      searchQuery = `site:${site} ${query}`;
    }

    // 尝试使用 Google Custom Search API
    const googleApiKey = this.configService.get<string>('GOOGLE_SEARCH_API_KEY');
    const googleCseId = this.configService.get<string>('GOOGLE_CSE_ID');

    if (googleApiKey && googleCseId) {
      try {
        const url = new URL('https://www.googleapis.com/customsearch/v1');
        url.searchParams.set('key', googleApiKey);
        url.searchParams.set('cx', googleCseId);
        url.searchParams.set('q', searchQuery);
        url.searchParams.set('lr', `lang_${language.split('-')[0]}`);
        url.searchParams.set('num', '5');

        const response = await fetch(url.toString());
        if (response.ok) {
          const data = (await response.json()) as { items?: Array<{ title: string; link: string; snippet: string }> };
          const results = (data.items || []).map((item: { title: string; link: string; snippet: string }) => ({
            title: item.title,
            url: item.link,
            snippet: item.snippet,
          }));

          return {
            success: true,
            query: searchQuery,
            results,
            resultCount: results.length,
            message: `找到 ${results.length} 条相关结果`,
          };
        }
      } catch (error) {
        console.error('[Tool:web_search] Google API error:', error);
      }
    }

    // 降级：返回建议用户自行搜索的信息
    return {
      success: false,
      query: searchQuery,
      results: [],
      message: '搜索服务暂时不可用。建议您访问以下官方网站获取最新信息：',
      suggestedSites: [
        { name: '香港入境事务处', url: 'https://www.immd.gov.hk' },
        { name: '香港人才服务窗口', url: 'https://www.talentservicewindow.gov.hk' },
        { name: '投资推广署', url: 'https://www.investhk.gov.hk' },
      ],
    };
  }

  /**
   * Get exchange rate - 获取实时汇率
   * 使用免费的汇率 API
   */
  private async getExchangeRate(input: Record<string, unknown>): Promise<unknown> {
    const { from, to, amount } = input as {
      from: string;
      to: string;
      amount?: number;
    };

    console.log(`[Tool:get_exchange_rate] From: ${from}, To: ${to}, Amount: ${amount || 'N/A'}`);

    // 使用 Exchange Rate API (免费层)
    const apiKey = this.configService.get<string>('EXCHANGE_RATE_API_KEY');
    const baseUrl = apiKey
      ? `https://v6.exchangerate-api.com/v6/${apiKey}/pair/${from}/${to}`
      : `https://api.exchangerate-api.com/v4/latest/${from}`;

    try {
      const response = await fetch(baseUrl);
      if (response.ok) {
        const data = (await response.json()) as {
          conversion_rate?: number;
          rates?: Record<string, number>;
          time_last_update_utc?: string;
        };

        let rate: number | undefined;
        if (apiKey) {
          // v6 API response
          rate = data.conversion_rate;
        } else {
          // v4 API response (free, no key needed)
          rate = data.rates?.[to];
        }

        if (rate) {
          const convertedAmount = amount ? amount * rate : null;
          return {
            success: true,
            from,
            to,
            rate,
            amount: amount || null,
            convertedAmount,
            lastUpdate: data.time_last_update_utc || new Date().toISOString(),
            message: amount
              ? `${amount} ${from} = ${convertedAmount?.toFixed(2)} ${to} (汇率: ${rate.toFixed(4)})`
              : `1 ${from} = ${rate.toFixed(4)} ${to}`,
          };
        }
      }
    } catch (error) {
      console.error('[Tool:get_exchange_rate] API error:', error);
    }

    // 降级：使用固定参考汇率
    const fallbackRates: Record<string, Record<string, number>> = {
      CNY: { HKD: 1.08, USD: 0.14 },
      USD: { HKD: 7.78, CNY: 7.24 },
      HKD: { CNY: 0.93, USD: 0.13 },
    };

    const fallbackRate = fallbackRates[from]?.[to];
    if (fallbackRate) {
      const convertedAmount = amount ? amount * fallbackRate : null;
      return {
        success: true,
        from,
        to,
        rate: fallbackRate,
        amount: amount || null,
        convertedAmount,
        isEstimate: true,
        message: `参考汇率 (可能有偏差): 1 ${from} ≈ ${fallbackRate} ${to}${amount ? `，${amount} ${from} ≈ ${convertedAmount?.toFixed(2)} ${to}` : ''}`,
      };
    }

    return {
      success: false,
      message: `暂不支持 ${from} 到 ${to} 的汇率查询`,
    };
  }

  /**
   * Fetch immigration news - 获取移民相关新闻
   * 从官方渠道或新闻源获取
   */
  private async fetchImmigrationNews(input: Record<string, unknown>): Promise<unknown> {
    const { category = 'ALL', limit = 5 } = input as {
      category?: string;
      limit?: number;
    };

    console.log(`[Tool:fetch_immigration_news] Category: ${category}, Limit: ${limit}`);

    // 尝试从 knowledge-service 获取最新新闻（如果有此功能）
    try {
      const response = await fetch(
        `${this.configService.get<string>('KNOWLEDGE_SERVICE_URL') || 'http://knowledge-service:3003'}/api/v1/news/immigration?category=${category}&limit=${limit}`,
      );

      if (response.ok) {
        const data = (await response.json()) as { success?: boolean; data?: Array<unknown> };
        if (data.success && data.data) {
          return {
            success: true,
            category,
            news: data.data,
            message: `获取到 ${data.data.length} 条${category === 'ALL' ? '' : category + '相关'}移民新闻`,
          };
        }
      }
    } catch {
      console.log('[Tool:fetch_immigration_news] Knowledge service news not available');
    }

    // 降级：返回静态参考信息和官方渠道
    const categoryNews: Record<string, Array<{ title: string; summary: string; date: string; source: string }>> = {
      QMAS: [
        {
          title: '优才计划持续接受申请',
          summary: '香港优才计划无配额限制，全年接受申请。申请人需符合基本资格要求，并通过计分制评核。',
          date: '2024-01',
          source: '香港入境事务处',
        },
      ],
      TTPS: [
        {
          title: '高才通计划最新动态',
          summary: '高端人才通行证计划持续运作，A/B/C三类申请通道开放。',
          date: '2024-01',
          source: '香港入境事务处',
        },
      ],
      CIES: [
        {
          title: '新资本投资者入境计划',
          summary: '投资门槛为3000万港币，需投资于许可资产类别。',
          date: '2024-03',
          source: '香港入境事务处',
        },
      ],
    };

    const newsItems = category === 'ALL'
      ? Object.values(categoryNews).flat()
      : categoryNews[category] || [];

    return {
      success: true,
      category,
      news: newsItems.slice(0, limit),
      isStatic: true,
      message: newsItems.length > 0
        ? `以下是${category === 'ALL' ? '' : category + '类别'}的参考信息。如需最新资讯，请访问香港入境事务处官网。`
        : '暂无相关新闻，建议访问香港入境事务处官网获取最新信息。',
      officialSources: [
        { name: '香港入境事务处', url: 'https://www.immd.gov.hk/hks/services/visas/admission_talents.html' },
        { name: '香港人才服务窗口', url: 'https://www.talentservicewindow.gov.hk' },
      ],
    };
  }
}