// 云函数：发送生日提醒
const cloud = require('wx-server-sdk')

cloud.init({
  env: cloud.DYNAMIC_CURRENT_ENV
})

const db = cloud.database()

// 模板ID
const TEMPLATE_ID = '6J7Stt-lu7DKU6jblJ0nZGq_D81z5glnksf7qWfy5Yw'

/**
 * 计算两个日期之间的天数差
 */
function getDaysUntil(targetDate) {
  const today = new Date()
  today.setHours(0, 0, 0, 0)
  
  const target = new Date(targetDate)
  target.setHours(0, 0, 0, 0)
  
  const diffTime = target - today
  const diffDays = Math.ceil(diffTime / (1000 * 60 * 60 * 24))
  
  return diffDays
}

/**
 * 格式化日期
 */
function formatDate(date) {
  const d = new Date(date)
  const year = d.getFullYear()
  const month = String(d.getMonth() + 1).padStart(2, '0')
  const day = String(d.getDate()).padStart(2, '0')
  return `${year}年${month}月${day}日`
}

const TYPE_NAMES = {
  birthday: '公历生日',
  lunar_birthday: '农历生日',
  wedding: '结婚纪念日',
  engagement: '订婚纪念日',
  other: '其他纪念日'
}

/**
 * 获取类型名称
 */
function getTypeName(type, customName) {
  if (type === 'other' && customName) return customName
  return TYPE_NAMES[type] || '纪念日'
}

/**
 * 获取今年的纪念日日期
 */
function getThisYearDate(anniversary) {
  const today = new Date()
  const currentYear = today.getFullYear()
  
  // 使用公历日期计算
  let thisYearDate = new Date(currentYear, anniversary.solarMonth - 1, anniversary.solarDay)
  
  // 如果今年的已经过了，计算明年的
  const daysUntil = getDaysUntil(thisYearDate)
  if (daysUntil < 0) {
    thisYearDate = new Date(currentYear + 1, anniversary.solarMonth - 1, anniversary.solarDay)
  }
  
  return thisYearDate
}

/**
 * 主函数
 */
exports.main = async (event, context) => {
  console.log('开始执行提醒任务...')
  
  try {
    // 获取所有启用提醒的纪念日
    const anniversariesRes = await db.collection('anniversaries')
      .where({
        remindEnabled: true
      })
      .get()
    
    console.log(`找到 ${anniversariesRes.data.length} 条启用提醒的纪念日`)
    
    let successCount = 0
    let failCount = 0
    
    // 遍历每个纪念日
    for (const anniversary of anniversariesRes.data) {
      try {
        // 计算今年的纪念日日期
        const thisYearDate = getThisYearDate(anniversary)
        const daysUntil = getDaysUntil(thisYearDate)
        
        console.log(`${anniversary.personName} 的 ${getTypeName(anniversary.type, anniversary.customTypeName)}，还有 ${daysUntil} 天`)
        
        // 判断是否需要提醒
        const shouldRemind = (
          daysUntil === 0 ||  // 当天
          daysUntil === anniversary.remindDays  // 提前N天
        )
        
        if (shouldRemind) {
          // 检查今天是否已经发送过提醒
          const today = new Date()
          today.setHours(0, 0, 0, 0)
          
          const logRes = await db.collection('remind_logs')
            .where({
              anniversaryId: anniversary._id,
              sendDate: db.command.gte(today)
            })
            .count()
          
          if (logRes.total > 0) {
            console.log(`今天已发送过提醒，跳过: ${anniversary.personName}`)
            continue
          }
          
          // 发送订阅消息
          const sendRes = await cloud.openapi.subscribeMessage.send({
            touser: anniversary.openid,
            page: 'pages/index/index',
            data: {
              name1: {
                value: anniversary.personName
              },
              thing2: {
                value: daysUntil === 0 ? '今天' : `还有${daysUntil}天`
              },
              thing6: {
                value: formatDate(thisYearDate)
              },
              thing5: {
                value: anniversary.remark || '别忘了准备一份礼物哦！'
              }
            },
            templateId: TEMPLATE_ID,
            miniprogramState: 'formal'  // 正式版
          })
          
          console.log(`发送成功: ${anniversary.personName}`, sendRes)
          
          // 记录提醒日志
          await db.collection('remind_logs').add({
            data: {
              anniversaryId: anniversary._id,
              personName: anniversary.personName,
              typeName: getTypeName(anniversary.type, anniversary.customTypeName),
              daysUntil: daysUntil,
              sendDate: new Date(),
              status: 'success'
            }
          })
          
          successCount++
        }
      } catch (err) {
        console.error(`发送失败: ${anniversary.personName}`, err)
        failCount++
        
        // 记录失败日志
        await db.collection('remind_logs').add({
          data: {
            anniversaryId: anniversary._id,
            personName: anniversary.personName,
            sendDate: new Date(),
            status: 'failed',
            error: err.message
          }
        })
      }
    }
    
    console.log(`提醒任务完成: 成功${successCount}条，失败${failCount}条`)
    
    return {
      success: true,
      total: anniversariesRes.data.length,
      successCount,
      failCount
    }
  } catch (err) {
    console.error('提醒任务执行失败:', err)
    return {
      success: false,
      error: err.message
    }
  }
}