import { NextRequest, NextResponse } from "next/server"
import { getServerSession } from "next-auth"
import { authOptions } from "@/lib/auth"
import { prisma } from "@/lib/prisma"
import { checkPermission } from "@/lib/permissions"
import { Role, Gender } from "@prisma/client"
import { z } from "zod"
import { recordMemberHistory } from "@/lib/member-history"
import { recalculateGenerations, getMinGeneration, findNewRootMember } from "@/lib/generation-utils"

const createMemberSchema = z.object({
  surname: z.string().min(1),
  givenName: z.string().min(1),
  fullName: z.string().min(1),
  gender: z.nativeEnum(Gender),
  generation: z.number().int().positive(),
  generationName: z.string().optional(),
  courtesyName: z.string().optional(),
  artName: z.string().optional(),
  posthumousName: z.string().optional(),
  rank: z.number().optional(),
  birthDate: z.string().optional(),
  deathDate: z.string().optional(),
  isLunarDate: z.boolean().optional(),
  ancestralHome: z.string().optional(),
  birthPlace: z.string().optional(),
  burialPlace: z.string().optional(),
  phone: z.string().optional(),
  telephone: z.string().optional(),
  email: z.string().optional(),
  address: z.string().optional(),
  fatherId: z.string().optional(),
  motherId: z.string().optional(),
  spouseIds: z.array(z.string()).optional(),
  childrenIds: z.array(z.string()).optional(),
  spouseFatherName: z.string().optional(),
  spouseMotherName: z.string().optional(),
  bio: z.string().optional(),
  tags: z.array(z.string()).optional(),
  avatarUrl: z.string().optional(),
  photoIds: z.array(z.string()).optional(),
})

// 获取家族树的所有成员
export async function GET(
  req: NextRequest,
  { params }: { params: Promise<{ treeId: string }> }
) {
  try {
    const session = await getServerSession(authOptions)
    
    if (!session?.user?.id) {
      return NextResponse.json({ error: "未授权" }, { status: 401 })
    }

    const { treeId } = await params

    // 检查权限
    const { hasPermission } = await checkPermission(session.user.id, treeId)
    if (!hasPermission) {
      return NextResponse.json({ error: "无权访问此家族树" }, { status: 403 })
    }

    // 并行获取家族树信息和成员数据
    const [tree, members] = await Promise.all([
      prisma.familyTree.findUnique({
        where: { id: treeId },
        select: { rootMemberId: true }
      }),
      prisma.familyMember.findMany({
        where: { treeId },
        orderBy: [
          { generation: 'asc' },
          { createdAt: 'asc' }
        ]
      })
    ])

    // 如果没有设置 rootMemberId，尝试找到第一代成员作为根
    let rootId = tree?.rootMemberId
    if (!rootId && members.length > 0) {
      const firstGenMember = members.find((m: any) => m.generation === 1)
      if (firstGenMember) {
        rootId = firstGenMember.id
        // 异步更新家族树的 rootMemberId（不阻塞响应）
        prisma.familyTree.update({
          where: { id: treeId },
          data: { rootMemberId: firstGenMember.id }
        }).catch(err => console.error('更新 rootMemberId 失败:', err))
      }
    }

    return NextResponse.json({ members, rootId })
  } catch (error) {
    console.error("获取成员失败:", error)
    return NextResponse.json(
      { error: "获取成员失败" },
      { status: 500 }
    )
  }
}

// 创建新成员
export async function POST(
  req: NextRequest,
  { params }: { params: Promise<{ treeId: string }> }
) {
  try {
    const session = await getServerSession(authOptions)
    
    if (!session?.user?.id) {
      return NextResponse.json({ error: "未授权" }, { status: 401 })
    }

    const { treeId } = await params

    // 检查权限（需要 EDITOR 权限）
    const { hasPermission } = await checkPermission(session.user.id, treeId, Role.EDITOR)
    if (!hasPermission) {
      return NextResponse.json({ error: "无权限添加成员" }, { status: 403 })
    }

    const body = await req.json()
    const data = createMemberSchema.parse(body)

    // 检查是否需要调整全族代数
    const minGeneration = await getMinGeneration(treeId)
    let needRecalculate = false
    let generationOffset = 0
    
    // 检查是否给第1代成员添加父母
    let isAddingParentToFounder = false
    if (data.childrenIds && data.childrenIds.length > 0) {
      // 检查子女中是否有第1代成员
      const children = await prisma.familyMember.findMany({
        where: {
          id: { in: data.childrenIds },
          generation: 1
        },
        select: { id: true }
      })
      isAddingParentToFounder = children.length > 0
    }
    
    if (minGeneration !== null && data.generation < minGeneration) {
      // 新成员的代数小于当前最小代数，需要调整全族代数
      needRecalculate = true
      generationOffset = minGeneration - data.generation
    } else if (isAddingParentToFounder && minGeneration === 1) {
      // 给第1代成员添加父母，需要将全族代数+1
      needRecalculate = true
      generationOffset = 1
    }

    const member = await prisma.familyMember.create({
      data: {
        ...data,
        treeId,
      }
    })

    // 维护配偶双向关系
    if (data.spouseIds && data.spouseIds.length > 0) {
      for (const spouseId of data.spouseIds) {
        const spouse = await prisma.familyMember.findUnique({
          where: { id: spouseId }
        })
        
        if (spouse && !spouse.spouseIds.includes(member.id)) {
          await prisma.familyMember.update({
            where: { id: spouseId },
            data: {
              spouseIds: [...spouse.spouseIds, member.id]
            }
          })
        }
      }
    }

    // 维护父母-子女双向关系
    // 1. 如果设置了父亲，将当前成员添加到父亲的子女列表
    if (data.fatherId) {
      const father = await prisma.familyMember.findUnique({
        where: { id: data.fatherId }
      })
      
      if (father && !father.childrenIds.includes(member.id)) {
        await prisma.familyMember.update({
          where: { id: data.fatherId },
          data: {
            childrenIds: [...father.childrenIds, member.id]
          }
        })
      }
    }

    // 2. 如果设置了母亲，将当前成员添加到母亲的子女列表
    if (data.motherId) {
      const mother = await prisma.familyMember.findUnique({
        where: { id: data.motherId }
      })
      
      if (mother && !mother.childrenIds.includes(member.id)) {
        await prisma.familyMember.update({
          where: { id: data.motherId },
          data: {
            childrenIds: [...mother.childrenIds, member.id]
          }
        })
      }
    }

    // 3. 如果设置了子女，将当前成员设置为子女的父亲或母亲
    if (data.childrenIds && data.childrenIds.length > 0) {
      for (const childId of data.childrenIds) {
        const child = await prisma.familyMember.findUnique({
          where: { id: childId }
        })
        
        if (child) {
          // 根据当前成员的性别设置为父亲或母亲
          if (data.gender === 'MALE' && !child.fatherId) {
            await prisma.familyMember.update({
              where: { id: childId },
              data: { fatherId: member.id }
            })
          } else if (data.gender === 'FEMALE' && !child.motherId) {
            await prisma.familyMember.update({
              where: { id: childId },
              data: { motherId: member.id }
            })
          }
        }
      }
    }

    // 如果需要调整全族代数
    if (needRecalculate) {
      try {
        if (isAddingParentToFounder) {
          // 给第1代成员添加父母的情况
          // 1. 先将所有现有成员的代数+1（包括原来的第1代）
          await recalculateGenerations(treeId, generationOffset, member.id)
          
          // 2. 将原始祖的 isFounder 设为 false
          const oldFounders = await prisma.familyMember.findMany({
            where: {
              treeId,
              isFounder: true,
              id: { not: member.id }
            }
          })
          for (const oldFounder of oldFounders) {
            await prisma.familyMember.update({
              where: { id: oldFounder.id },
              data: { isFounder: false }
            })
          }
          
          // 3. 新父母成员保持代数为1，并设为始祖
          await prisma.familyMember.update({
            where: { id: member.id },
            data: { generation: 1, isFounder: true }
          })
          
          // 4. 更新家族树的 rootMemberId 为新父母
          await prisma.familyTree.update({
            where: { id: treeId },
            data: { rootMemberId: member.id }
          })
        } else {
          // 其他情况：新成员代数小于最小代数
          // 调整其他成员的代数（排除新创建的成员）
          await recalculateGenerations(treeId, generationOffset, member.id)
          
          // 将新成员的代数设为1（成为新的始祖）
          await prisma.familyMember.update({
            where: { id: member.id },
            data: { generation: 1 }
          })
          
          // 更新家族树的 rootMemberId
          await prisma.familyTree.update({
            where: { id: treeId },
            data: { rootMemberId: member.id }
          })
        }
        
        // 记录全族代数调整的日志
        await prisma.activityLog.create({
          data: {
            treeId,
            userId: session.user.id,
            action: 'UPDATE',
            entityType: 'TREE',
            entityId: treeId,
            entityName: `全族代数调整（+${generationOffset}代）`,
            changes: {
              reason: isAddingParentToFounder ? '给始祖添加父母' : '添加更早代数成员',
              offset: generationOffset,
              newRootMemberId: member.id
            }
          }
        })
      } catch (error) {
        console.error('调整全族代数失败:', error)
        // 如果调整失败，删除新创建的成员
        await prisma.familyMember.delete({ where: { id: member.id } })
        throw new Error('调整全族代数失败，操作已回滚')
      }
    }

    // 记录成员历史版本
    await recordMemberHistory({
      memberId: member.id,
      treeId,
      changedBy: session.user.id,
      changeType: 'CREATE',
      newData: member
    })

    // 记录操作日志
    await prisma.activityLog.create({
      data: {
        treeId,
        userId: session.user.id,
        action: 'CREATE',
        entityType: 'MEMBER',
        entityId: member.id,
        entityName: member.fullName,
      }
    })

    return NextResponse.json({ 
      member, 
      generationRecalculated: needRecalculate,
      generationOffset: needRecalculate ? generationOffset : 0
    }, { status: 201 })
  } catch (error) {
    if (error instanceof z.ZodError) {
      return NextResponse.json(
        { error: error.errors[0].message },
        { status: 400 }
      )
    }
    
    console.error("创建成员失败:", error)
    return NextResponse.json(
      { error: "创建成员失败" },
      { status: 500 }
    )
  }
}