import type { FamilyMember, FamilyTreeData } from "@/types/family"
import { parseGedcom } from "read-gedcom"

/**
 * 将 FamilyTreeData 导出为 GEDCOM 格式
 */
export function exportToGedcom(treeData: FamilyTreeData): string {
  const lines: string[] = []
  
  // GEDCOM Header
  lines.push("0 HEAD")
  lines.push("1 SOUR Chinese Family Tree")
  lines.push("2 VERS 1.0")
  lines.push("2 NAME 华夏谱")
  lines.push("1 DEST ANY")
  lines.push("1 DATE " + new Date().toISOString().split('T')[0].replace(/-/g, ' '))
  lines.push("1 CHAR UTF-8")
  lines.push("1 GEDC")
  lines.push("2 VERS 5.5.1")
  lines.push("2 FORM LINEAGE-LINKED")
  
  const members = Object.values(treeData.members)
  
  // 个人记录 (INDI)
  members.forEach(member => {
    lines.push(`0 @I${member.id}@ INDI`)
    lines.push(`1 NAME ${member.fullName}`)
    lines.push(`2 GIVN ${member.givenName}`)
    lines.push(`2 SURN ${member.surname}`)
    
    if (member.courtesyName) {
      lines.push(`2 _AKA ${member.courtesyName}`)
    }
    
    if (member.gender === 'MALE') {
      lines.push("1 SEX M")
    } else if (member.gender === 'FEMALE') {
      lines.push("1 SEX F")
    }
    
    // 出生信息
    if (member.birthDate) {
      lines.push("1 BIRT")
      lines.push(`2 DATE ${formatGedcomDate(member.birthDate)}`)
      if (member.birthPlace) {
        lines.push(`2 PLAC ${member.birthPlace}`)
      }
    }
    
    // 逝世信息
    if (member.deathDate) {
      lines.push("1 DEAT")
      lines.push(`2 DATE ${formatGedcomDate(member.deathDate)}`)
      if (member.burialPlace) {
        lines.push(`2 PLAC ${member.burialPlace}`)
      }
    }
    
    // 籍贯
    if (member.ancestralHome) {
      lines.push("1 RESI")
      lines.push(`2 PLAC ${member.ancestralHome}`)
    }
    
    // 备注
    if (member.bio) {
      lines.push("1 NOTE " + member.bio.replace(/\n/g, "\n1 CONT "))
    }
    
    // 家庭关系 - 作为子女
    if (member.fatherId || member.motherId) {
      const famId = `F${member.fatherId || member.motherId}_${member.id}`
      lines.push(`1 FAMC @${famId}@`)
    }
    
    // 家庭关系 - 作为配偶
    if (member.spouseIds.length > 0) {
      member.spouseIds.forEach(spouseId => {
        const famId = `F${member.id}_${spouseId}`
        lines.push(`1 FAMS @${famId}@`)
      })
    }
  })
  
  // 家庭记录 (FAM)
  const processedFamilies = new Set<string>()
  
  members.forEach(member => {
    // 创建父母家庭
    if (member.fatherId || member.motherId) {
      const famId = `F${member.fatherId || member.motherId}_${member.id}`
      if (!processedFamilies.has(famId)) {
        lines.push(`0 @${famId}@ FAM`)
        if (member.fatherId) {
          lines.push(`1 HUSB @I${member.fatherId}@`)
        }
        if (member.motherId) {
          lines.push(`1 WIFE @I${member.motherId}@`)
        }
        
        // 查找所有同父母的子女
        const siblings = members.filter(m => 
          m.fatherId === member.fatherId && m.motherId === member.motherId
        )
        siblings.forEach(child => {
          lines.push(`1 CHIL @I${child.id}@`)
        })
        
        processedFamilies.add(famId)
      }
    }
    
    // 创建配偶家庭
    if (member.spouseIds.length > 0) {
      member.spouseIds.forEach(spouseId => {
        const famId = member.gender === 'MALE' 
          ? `F${member.id}_${spouseId}`
          : `F${spouseId}_${member.id}`
          
        if (!processedFamilies.has(famId)) {
          lines.push(`0 @${famId}@ FAM`)
          
          if (member.gender === 'MALE') {
            lines.push(`1 HUSB @I${member.id}@`)
            lines.push(`1 WIFE @I${spouseId}@`)
          } else {
            lines.push(`1 HUSB @I${spouseId}@`)
            lines.push(`1 WIFE @I${member.id}@`)
          }
          
          // 添加子女
          member.childrenIds.forEach(childId => {
            lines.push(`1 CHIL @I${childId}@`)
          })
          
          processedFamilies.add(famId)
        }
      })
    }
  })
  
  // GEDCOM Trailer
  lines.push("0 TRLR")
  
  return lines.join("\n")
}

/**
 * 从 GEDCOM 格式导入数据
 */
export function importFromGedcom(gedcomText: string): FamilyTreeData {
  const parsed = parseGedcom(gedcomText as any)
  const members: Record<string, FamilyMember> = {}
  let rootId: string | undefined
  
  // 第一遍：创建所有个人
  const records = Array.isArray(parsed) ? parsed : (parsed as any).tree || []
  records.forEach((record: any) => {
    if (record.tag === 'INDI') {
      const id = record.pointer.replace('@I', '').replace('@', '')
      
      let fullName = ''
      let givenName = ''
      let surname = ''
      let courtesyName: string | undefined
      let gender: 'MALE' | 'FEMALE' | 'OTHER' = 'OTHER'
      let birthDate: string | undefined
      let deathDate: string | undefined
      let birthPlace: string | undefined
      let burialPlace: string | undefined
      let ancestralHome: string | undefined
      let bio: string | undefined
      
      record.tree.forEach((field: any) => {
        if (field.tag === 'NAME') {
          fullName = field.data.replace(/\//g, '').trim()
          field.tree?.forEach((subField: any) => {
            if (subField.tag === 'GIVN') givenName = subField.data
            if (subField.tag === 'SURN') surname = subField.data
            if (subField.tag === '_AKA') courtesyName = subField.data
          })
        }
        if (field.tag === 'SEX') {
          gender = field.data === 'M' ? 'MALE' : field.data === 'F' ? 'FEMALE' : 'OTHER'
        }
        if (field.tag === 'BIRT') {
          field.tree?.forEach((subField: any) => {
            if (subField.tag === 'DATE') birthDate = parseGedcomDate(subField.data)
            if (subField.tag === 'PLAC') birthPlace = subField.data
          })
        }
        if (field.tag === 'DEAT') {
          field.tree?.forEach((subField: any) => {
            if (subField.tag === 'DATE') deathDate = parseGedcomDate(subField.data)
            if (subField.tag === 'PLAC') burialPlace = subField.data
          })
        }
        if (field.tag === 'RESI') {
          field.tree?.forEach((subField: any) => {
            if (subField.tag === 'PLAC') ancestralHome = subField.data
          })
        }
        if (field.tag === 'NOTE') {
          bio = field.data
        }
      })
      
      members[id] = {
        id,
        surname: surname || '未知',
        givenName: givenName || fullName,
        fullName: fullName || `${surname}${givenName}`,
        gender,
        generation: 1, // 将在第二遍中计算
        courtesyName,
        birthDate,
        deathDate,
        birthPlace,
        burialPlace,
        ancestralHome,
        bio,
        spouseIds: [],
        childrenIds: [],
        createdAt: new Date().toISOString(),
        updatedAt: new Date().toISOString(),
      }
    }
  })
  
  // 第二遍：建立关系
  records.forEach((record: any) => {
    if (record.tag === 'FAM') {
      let husbId: string | undefined
      let wifeId: string | undefined
      const childIds: string[] = []
      
      record.tree.forEach((field: any) => {
        if (field.tag === 'HUSB') {
          husbId = field.data.replace('@I', '').replace('@', '')
        }
        if (field.tag === 'WIFE') {
          wifeId = field.data.replace('@I', '').replace('@', '')
        }
        if (field.tag === 'CHIL') {
          childIds.push(field.data.replace('@I', '').replace('@', ''))
        }
      })
      
      // 设置配偶关系
      if (husbId && wifeId) {
        if (members[husbId] && !members[husbId].spouseIds.includes(wifeId)) {
          members[husbId].spouseIds.push(wifeId)
        }
        if (members[wifeId] && !members[wifeId].spouseIds.includes(husbId)) {
          members[wifeId].spouseIds.push(husbId)
        }
      }
      
      // 设置父母-子女关系
      childIds.forEach(childId => {
        if (members[childId]) {
          if (husbId) {
            members[childId].fatherId = husbId
            if (members[husbId] && !members[husbId].childrenIds.includes(childId)) {
              members[husbId].childrenIds.push(childId)
            }
          }
          if (wifeId) {
            members[childId].motherId = wifeId
            if (members[wifeId] && !members[wifeId].childrenIds.includes(childId)) {
              members[wifeId].childrenIds.push(childId)
            }
          }
        }
      })
    }
  })
  
  // 计算世代并找到根节点
  const calculateGeneration = (id: string, visited = new Set<string>()): number => {
    if (visited.has(id)) return 1 // 防止循环引用
    visited.add(id)
    
    const member = members[id]
    if (!member) return 1
    
    if (!member.fatherId && !member.motherId) {
      return 1 // 根节点
    }
    
    const fatherGen = member.fatherId ? calculateGeneration(member.fatherId, visited) : 0
    const motherGen = member.motherId ? calculateGeneration(member.motherId, visited) : 0
    
    return Math.max(fatherGen, motherGen) + 1
  }
  
  Object.keys(members).forEach(id => {
    members[id].generation = calculateGeneration(id)
  })
  
  // 找到第一代作为根节点
  rootId = Object.keys(members).find(id => members[id].generation === 1)
  
  return {
    members,
    rootId,
  }
}

// 辅助函数：格式化日期为 GEDCOM 格式
function formatGedcomDate(isoDate: string): string {
  const date = new Date(isoDate)
  const months = ['JAN', 'FEB', 'MAR', 'APR', 'MAY', 'JUN', 'JUL', 'AUG', 'SEP', 'OCT', 'NOV', 'DEC']
  return `${date.getDate()} ${months[date.getMonth()]} ${date.getFullYear()}`
}

// 辅助函数：解析 GEDCOM 日期为 ISO 格式
function parseGedcomDate(gedcomDate: string): string {
  const months: Record<string, number> = {
    JAN: 0, FEB: 1, MAR: 2, APR: 3, MAY: 4, JUN: 5,
    JUL: 6, AUG: 7, SEP: 8, OCT: 9, NOV: 10, DEC: 11
  }
  
  const parts = gedcomDate.trim().split(' ')
  if (parts.length === 3) {
    const day = parseInt(parts[0])
    const month = months[parts[1].toUpperCase()]
    const year = parseInt(parts[2])
    
    if (!isNaN(day) && month !== undefined && !isNaN(year)) {
      return new Date(year, month, day).toISOString().split('T')[0]
    }
  }
  
  // 如果只有年份
  if (parts.length === 1 && !isNaN(parseInt(parts[0]))) {
    return `${parts[0]}-01-01`
  }
  
  return new Date().toISOString().split('T')[0]
}