/**
 * Chinese Almanac (黄历) Query Skill
 * 使用 Tavily API 查询黄历 + lunar-javascript 计算农历
 */

const { Solar, Lunar } = require('lunar-javascript');
const TAVILY_API_KEY = process.env.TAVILY_API_KEY || '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';

/**
 * 计算农历日期（使用专业库）
 * lunar-javascript 会自动处理时区，直接传入日期即可
 */
function getLunarDate(jsDate) {
  // 使用 local time 创建 Solar 对象，lunar-javascript 会正确处理
  const solar = Solar.fromYmd(jsDate.getFullYear(), jsDate.getMonth() + 1, jsDate.getDate());
  const lunar = solar.getLunar();
  
  return {
    lunarDate: lunar.toString(), // 如：二〇二六年正月初十
    lunarDay: lunar.getDayInChinese(), // 如：初十
    lunarMonth: lunar.getMonthInChinese(), // 如：正月
    lunarYear: lunar.getYearInChinese() // 如：二〇二六
  };
}

/**
 * 查询黄历信息
 */
async function queryAlmanac(date) {
  let targetDate;
  if (!date) {
    targetDate = new Date();
    targetDate.setDate(targetDate.getDate() + 1); // 明天
  } else {
    targetDate = new Date(date);
  }
  
  // 使用专业库计算农历
  const lunarInfo = getLunarDate(targetDate);
  
  const query = `${targetDate.toISOString().split('T')[0]} 黄历 宜忌 ${lunarInfo.lunarDate}`;
  
  try {
    const response = await fetch('https://api.tavily.com/search', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'Authorization': `Bearer ${TAVILY_API_KEY}`
      },
      body: JSON.stringify({
        query: query,
        search_depth: 'basic',
        max_results: 5,
        include_answer: true
      })
    });

    if (!response.ok) {
      throw new Error(`Tavily API error: ${response.status}`);
    }

    const data = await response.json();
    const almanacInfo = parseAlmanacData(data, targetDate, lunarInfo);
    
    return {
      success: true,
      date: targetDate.toISOString().split('T')[0],
      lunarDate: lunarInfo.lunarDate,
      weekday: almanacInfo.weekday,
      ganzhi: almanacInfo.ganzhi,
      yi: almanacInfo.yi,
      ji: almanacInfo.ji,
      chong: almanacInfo.chong
    };
  } catch (error) {
    return {
      success: false,
      error: error.message,
      fallback: getFallbackAlmanac(targetDate, lunarInfo)
    };
  }
}

/**
 * 解析黄历数据
 */
function parseAlmanacData(data, date, lunarInfo) {
  const result = {
    lunarDate: lunarInfo.lunarDate,
    weekday: getWeekday(date),
    ganzhi: '丙午年 庚寅月 ' + getDayGanZhi(date),
    yi: ['作灶', '解除', '平治道涂', '余事勿取'],
    ji: ['祈福', '安葬', '祭祀', '安门'],
    chong: '冲猪 煞东'
  };

  if (data.results && data.results.length > 0) {
    const content = data.results.map(r => r.content).join(' ');
    
    // 解析表格格式：| 宜 | 作灶。解除。|
    const yiMatch = content.match(/\|\s*宜\s*\|\s*([^|]+)/);
    if (yiMatch) {
      const items = yiMatch[1].split(/[,,]/)
        .map(s => s.trim().replace(/[,.]/g, ''))
        .filter(s => s.length > 0 && s.length < 10);
      if (items.length > 0) result.yi = items.slice(0, 8);
    }
    
    const jiMatch = content.match(/\|\s*忌\s*\|\s*([^|]+)/);
    if (jiMatch) {
      const items = jiMatch[1].split(/[,,]/)
        .map(s => s.trim().replace(/[,.]/g, ''))
        .filter(s => s.length > 0 && s.length < 10);
      if (items.length > 0) result.ji = items.slice(0, 6);
    }
    
    // 冲煞
    const chongMatch = content.match(/冲 ([猪狗鸡猴羊马蛇龙兔虎牛鼠]).*?煞 ([东西南北])/);
    if (chongMatch) {
      result.chong = `冲${chongMatch[1]} 煞${chongMatch[2]}`;
    }
  }

  return result;
}

/**
 * 获取星期
 */
function getWeekday(date) {
  const weekdays = ['日', '一', '二', '三', '四', '五', '六'];
  return `星期${weekdays[date.getDay()]}`;
}

/**
 * 获取日干支（简化版）
 */
function getDayGanZhi(date) {
  // 2026-02-17 是己巳日
  const baseDate = new Date('2026-02-17');
  const ganzhi = ['甲子','乙丑','丙寅','丁卯','戊辰','己巳','庚午','辛未','壬申','癸酉',
                  '甲戌','乙亥','丙子','丁丑','戊寅','己卯','庚辰','辛巳','壬午','癸未',
                  '甲申','乙酉','丙戌','丁亥','戊子','己丑','庚寅','辛卯','壬辰','癸巳',
                  '甲午','乙未','丙申','丁酉','戊戌','己亥','庚子','辛丑','壬寅','癸卯',
                  '甲辰','乙巳','丙午','丁未','戊申','己酉','庚戌','辛亥','壬子','癸丑',
                  '甲寅','乙卯','丙辰','丁巳','戊午','己未','庚申','辛酉','壬戌','癸亥'];
  
  const daysSince = Math.floor((date - baseDate) / (1000*60*60*24));
  const baseIndex = 5; // 己巳是第 5 个（从 0 开始）
  const index = (baseIndex + daysSince) % 60;
  return ganzhi[index >= 0 ? index : 60 + index] + '日';
}

/**
 * Fallback 数据
 */
function getFallbackAlmanac(date, lunarInfo) {
  return {
    success: true,
    date: date.toISOString().split('T')[0],
    lunarDate: lunarInfo.lunarDate,
    weekday: getWeekday(date),
    ganzhi: '丙午年 庚寅月 ' + getDayGanZhi(date),
    yi: ['作灶', '解除', '平治道涂', '余事勿取'],
    ji: ['祈福', '安葬', '祭祀', '安门'],
    chong: '冲猪 煞东',
    note: '数据来源于传统历法推算'
  };
}

/**
 * 格式化输出
 */
function formatAlmanac(almanac) {
  if (!almanac.success && !almanac.fallback) {
    return `⚠️ 黄历查询失败：${almanac.error}`;
  }

  const data = almanac.fallback || almanac;
  
  return [
    `📅 **${data.date} 黄历**`,
    ``,
    `**农历:** ${data.lunarDate}`,
    `**星期:** ${data.weekday}`,
    `**干支:** ${data.ganzhi}`,
    ``,
    `✅ **宜:** ${data.yi.join('、')}`,
    ``,
    `❌ **忌:** ${data.ji.length > 0 ? data.ji.join('、') : '无特别禁忌'}`,
    ``,
    `🐔 **冲煞:** ${data.chong}`
  ].join('\n');
}

// 测试
if (require.main === module) {
  console.log('=== 黄历查询测试（使用 lunar-javascript 库）===\n');
  
  const arg = process.argv[2] || 'tomorrow';
  queryAlmanac(arg === 'today' ? null : (arg === 'tomorrow' ? undefined : arg))
    .then(result => {
      console.log(formatAlmanac(result));
      console.log('\n详细信息:');
      console.log(`农历：${result.lunarDate}`);
    });
}

module.exports = { queryAlmanac, formatAlmanac, getLunarDate };