/**
 * 用户管理服务
 * @description 提供用户 CRUD、租户隔离、模块权限管理等功能
 */

import { PrismaClient, UserRole, Prisma } from '@prisma/client';
import bcrypt from 'bcryptjs';
import { v4 as uuidv4 } from 'uuid';
import { logger } from '../../../common/logging/index.js';
import {
  ListUsersQuery,
  CreateUserRequest,
  UpdateUserRequest,
  AssignTenantRequest,
  UpdateUserModulesRequest,
  UserListItem,
  UserDetail,
  TenantMembership,
  PaginatedResponse,
  UserQueryScope,
  ImportUserRow,
  ImportResult,
  ImportError,
} from '../types/user.types.js';

const prisma = new PrismaClient();

// 默认密码
const DEFAULT_PASSWORD = '123456';

/**
 * 根据用户ID获取用户的 departmentId
 */
export async function getUserDepartmentId(userId: string): Promise<string | undefined> {
  const user = await prisma.user.findUnique({
    where: { id: userId },
    select: { department_id: true },
  });
  return user?.department_id || undefined;
}

/**
 * 根据用户角色获取查询范围
 */
export async function getUserQueryScope(
  userRole: UserRole | string,
  tenantId?: string,
  userId?: string
): Promise<UserQueryScope> {
  switch (userRole) {
    case 'SUPER_ADMIN':
    case 'PROMPT_ENGINEER':
      return {}; // 无限制
    case 'HOSPITAL_ADMIN':
    case 'PHARMA_ADMIN':
      return { tenantId }; // 只能查看本租户
    case 'DEPARTMENT_ADMIN': {
      // 科室主任需要查询其 departmentId
      const departmentId = userId ? await getUserDepartmentId(userId) : undefined;
      return { tenantId, departmentId };
    }
    default:
      throw new Error('无权限访问用户管理');
  }
}

/**
 * 获取用户列表（支持分页、搜索、筛选）
 */
export async function listUsers(
  query: ListUsersQuery,
  scope: UserQueryScope
): Promise<PaginatedResponse<UserListItem>> {
  // 确保 page 和 pageSize 是数字类型（HTTP 查询参数默认是字符串）
  const page = Number(query.page) || 1;
  const pageSize = Number(query.pageSize) || 20;
  const { search, role, tenantId, status, departmentId } = query;
  const skip = (page - 1) * pageSize;

  // 构建查询条件
  const where: Prisma.UserWhereInput = {};

  // 数据隔离：根据 scope 限制查询范围
  if (scope.tenantId) {
    where.tenant_id = scope.tenantId;
  }
  if (scope.departmentId) {
    where.department_id = scope.departmentId;
  }

  // 搜索条件
  if (search) {
    where.OR = [
      { phone: { contains: search } },
      { name: { contains: search } },
      { email: { contains: search } },
    ];
  }

  // 筛选条件
  if (role) {
    where.role = role;
  }
  if (tenantId && !scope.tenantId) {
    // 只有无限制 scope 才能按租户筛选
    where.tenant_id = tenantId;
  }
  if (status) {
    where.status = status;
  }
  if (departmentId && !scope.departmentId) {
    where.department_id = departmentId;
  }

  // 查询总数
  const total = await prisma.user.count({ where });

  // 查询列表
  const users = await prisma.user.findMany({
    where,
    skip,
    take: pageSize,
    orderBy: { createdAt: 'desc' },
    include: {
      tenants: {
        select: {
          id: true,
          code: true,
          name: true,
          type: true,
        },
      },
      departments: {
        select: {
          id: true,
          name: true,
        },
      },
      tenant_members: {
        select: {
          id: true,
        },
      },
    },
  });

  // 转换为列表项
  const data: UserListItem[] = users.map((user) => ({
    id: user.id,
    phone: user.phone,
    name: user.name,
    email: user.email,
    role: user.role,
    status: user.status,
    isDefaultPassword: user.is_default_password,
    defaultTenant: {
      id: user.tenants.id,
      code: user.tenants.code,
      name: user.tenants.name,
      type: user.tenants.type,
    },
    department: user.departments
      ? {
          id: user.departments.id,
          name: user.departments.name,
        }
      : null,
    tenantCount: user.tenant_members.length,
    createdAt: user.createdAt,
    lastLoginAt: user.lastLoginAt,
  }));

  return {
    data,
    total,
    page,
    pageSize,
    totalPages: Math.ceil(total / pageSize),
  };
}

/**
 * 获取用户详情
 */
export async function getUserById(userId: string, scope: UserQueryScope): Promise<UserDetail | null> {
  const where: Prisma.UserWhereInput = { id: userId };

  // 数据隔离
  if (scope.tenantId) {
    where.tenant_id = scope.tenantId;
  }

  const user = await prisma.user.findFirst({
    where,
    include: {
      tenants: {
        select: {
          id: true,
          code: true,
          name: true,
          type: true,
        },
      },
      departments: {
        select: {
          id: true,
          name: true,
        },
      },
      tenant_members: {
        include: {
          tenants: {
            select: {
              id: true,
              code: true,
              name: true,
              type: true,
            },
          },
        },
      },
      user_modules: {
        include: {
          tenant: {
            select: {
              id: true,
              code: true,
            },
          },
        },
      },
    },
  });

  if (!user) {
    return null;
  }

  // 获取每个租户的模块权限
  const tenantMemberships: TenantMembership[] = await Promise.all(
    user.tenant_members.map(async (tm) => {
      // 获取租户订阅的模块
      const tenantModules = await prisma.tenant_modules.findMany({
        where: { tenant_id: tm.tenants.id, is_enabled: true },
      });

      // 获取用户在该租户的模块权限
      const userModulesInTenant = user.user_modules.filter(
        (um) => um.tenant_id === tm.tenants.id
      );

      // 计算最终模块权限
      const allowedModules = tenantModules.map((tm) => {
        const userModule = userModulesInTenant.find((um) => um.module_code === tm.module_code);
        return {
          code: tm.module_code,
          name: getModuleName(tm.module_code),
          isEnabled: userModule ? userModule.is_enabled : true, // 默认继承租户权限
        };
      });

      return {
        tenantId: tm.tenants.id,
        tenantCode: tm.tenants.code,
        tenantName: tm.tenants.name,
        tenantType: tm.tenants.type,
        role: tm.role,
        joinedAt: tm.joined_at,
        allowedModules,
      };
    })
  );

  // 获取用户权限（基于角色）
  const rolePermissions = await prisma.role_permissions.findMany({
    where: { role: user.role },
    include: { permissions: true },
  });
  const permissions = rolePermissions.map((rp) => rp.permissions.code);

  return {
    id: user.id,
    phone: user.phone,
    name: user.name,
    email: user.email,
    role: user.role,
    status: user.status,
    isDefaultPassword: user.is_default_password,
    defaultTenant: {
      id: user.tenants.id,
      code: user.tenants.code,
      name: user.tenants.name,
      type: user.tenants.type,
    },
    department: user.departments
      ? {
          id: user.departments.id,
          name: user.departments.name,
        }
      : null,
    tenantCount: user.tenant_members.length,
    createdAt: user.createdAt,
    lastLoginAt: user.lastLoginAt,
    tenantMemberships,
    permissions,
  };
}

/**
 * 创建用户
 */
export async function createUser(data: CreateUserRequest, creatorId: string): Promise<UserDetail> {
  // 检查手机号是否已存在
  const existingUser = await prisma.user.findUnique({
    where: { phone: data.phone },
  });
  if (existingUser) {
    throw new Error('手机号已存在');
  }

  // 检查邮箱是否已存在
  if (data.email) {
    const existingEmail = await prisma.user.findUnique({
      where: { email: data.email },
    });
    if (existingEmail) {
      throw new Error('邮箱已存在');
    }
  }

  // 检查租户是否存在
  const tenant = await prisma.tenants.findUnique({
    where: { id: data.tenantId },
  });
  if (!tenant) {
    throw new Error('租户不存在');
  }

  // 检查科室是否存在（如果提供）
  if (data.departmentId) {
    const department = await prisma.departments.findFirst({
      where: { id: data.departmentId, tenant_id: data.tenantId },
    });
    if (!department) {
      throw new Error('科室不存在或不属于该租户');
    }
  }

  // 加密密码
  const hashedPassword = await bcrypt.hash(DEFAULT_PASSWORD, 10);

  // 创建用户和租户成员关系
  const userId = uuidv4();
  const tenantMemberId = uuidv4();

  const user = await prisma.$transaction(async (tx) => {
    // 创建用户
    const newUser = await tx.user.create({
      data: {
        id: userId,
        phone: data.phone,
        name: data.name,
        email: data.email,
        password: hashedPassword,
        role: data.role,
        tenant_id: data.tenantId,
        department_id: data.departmentId,
        is_default_password: true,
        status: 'active',
      },
    });

    // 创建租户成员关系
    await tx.tenant_members.create({
      data: {
        id: tenantMemberId,
        tenant_id: data.tenantId,
        user_id: userId,
        role: data.tenantRole || data.role,
      },
    });

    // 如果指定了模块权限，创建用户模块记录
    if (data.allowedModules && data.allowedModules.length > 0) {
      await tx.user_modules.createMany({
        data: data.allowedModules.map((moduleCode) => ({
          id: uuidv4(),
          user_id: userId,
          tenant_id: data.tenantId,
          module_code: moduleCode,
          is_enabled: true,
        })),
      });
    }

    return newUser;
  });

  logger.info('[UserService] User created', {
    userId: user.id,
    phone: user.phone,
    createdBy: creatorId,
  });

  // 返回用户详情
  return (await getUserById(user.id, {}))!;
}

/**
 * 更新用户
 */
export async function updateUser(
  userId: string,
  data: UpdateUserRequest,
  scope: UserQueryScope,
  updaterId: string
): Promise<UserDetail> {
  // 检查用户是否存在且在权限范围内
  const existingUser = await prisma.user.findFirst({
    where: {
      id: userId,
      ...(scope.tenantId ? { tenant_id: scope.tenantId } : {}),
    },
  });

  if (!existingUser) {
    throw new Error('用户不存在或无权限操作');
  }

  // 检查邮箱唯一性
  if (data.email && data.email !== existingUser.email) {
    const existingEmail = await prisma.user.findUnique({
      where: { email: data.email },
    });
    if (existingEmail) {
      throw new Error('邮箱已存在');
    }
  }

  // 更新用户
  await prisma.user.update({
    where: { id: userId },
    data: {
      name: data.name,
      email: data.email,
      role: data.role,
      department_id: data.departmentId,
      status: data.status,
    },
  });

  logger.info('[UserService] User updated', {
    userId,
    updatedFields: Object.keys(data),
    updatedBy: updaterId,
  });

  return (await getUserById(userId, scope))!;
}

/**
 * 更新用户状态（启用/禁用）
 */
export async function updateUserStatus(
  userId: string,
  status: 'active' | 'disabled',
  scope: UserQueryScope,
  updaterId: string
): Promise<void> {
  const existingUser = await prisma.user.findFirst({
    where: {
      id: userId,
      ...(scope.tenantId ? { tenant_id: scope.tenantId } : {}),
    },
  });

  if (!existingUser) {
    throw new Error('用户不存在或无权限操作');
  }

  await prisma.user.update({
    where: { id: userId },
    data: { status },
  });

  logger.info('[UserService] User status updated', {
    userId,
    status,
    updatedBy: updaterId,
  });
}

/**
 * 重置用户密码
 */
export async function resetUserPassword(
  userId: string,
  scope: UserQueryScope,
  resetterId: string
): Promise<void> {
  const existingUser = await prisma.user.findFirst({
    where: {
      id: userId,
      ...(scope.tenantId ? { tenant_id: scope.tenantId } : {}),
    },
  });

  if (!existingUser) {
    throw new Error('用户不存在或无权限操作');
  }

  const hashedPassword = await bcrypt.hash(DEFAULT_PASSWORD, 10);

  await prisma.user.update({
    where: { id: userId },
    data: {
      password: hashedPassword,
      is_default_password: true,
      password_changed_at: null,
    },
  });

  logger.info('[UserService] User password reset', {
    userId,
    resetBy: resetterId,
  });
}

/**
 * 分配租户给用户
 */
export async function assignTenantToUser(
  userId: string,
  data: AssignTenantRequest,
  assignerId: string
): Promise<void> {
  // 检查用户是否存在
  const user = await prisma.user.findUnique({ where: { id: userId } });
  if (!user) {
    throw new Error('用户不存在');
  }

  // 检查租户是否存在
  const tenant = await prisma.tenants.findUnique({ where: { id: data.tenantId } });
  if (!tenant) {
    throw new Error('租户不存在');
  }

  // 检查是否已是该租户成员
  const existingMember = await prisma.tenant_members.findUnique({
    where: {
      tenant_id_user_id: {
        tenant_id: data.tenantId,
        user_id: userId,
      },
    },
  });

  if (existingMember) {
    throw new Error('用户已是该租户成员');
  }

  // 创建租户成员关系
  await prisma.$transaction(async (tx) => {
    await tx.tenant_members.create({
      data: {
        id: uuidv4(),
        tenant_id: data.tenantId,
        user_id: userId,
        role: data.role,
      },
    });

    // 如果指定了模块权限，创建用户模块记录
    if (data.allowedModules && data.allowedModules.length > 0) {
      await tx.user_modules.createMany({
        data: data.allowedModules.map((moduleCode) => ({
          id: uuidv4(),
          user_id: userId,
          tenant_id: data.tenantId,
          module_code: moduleCode,
          is_enabled: true,
        })),
      });
    }
  });

  logger.info('[UserService] Tenant assigned to user', {
    userId,
    tenantId: data.tenantId,
    assignedBy: assignerId,
  });
}

/**
 * 从租户移除用户
 */
export async function removeTenantFromUser(
  userId: string,
  tenantId: string,
  removerId: string
): Promise<void> {
  // 检查用户是否存在
  const user = await prisma.user.findUnique({ where: { id: userId } });
  if (!user) {
    throw new Error('用户不存在');
  }

  // 不能移除默认租户
  if (user.tenant_id === tenantId) {
    throw new Error('不能移除用户的默认租户');
  }

  // 检查租户成员关系是否存在
  const membership = await prisma.tenant_members.findUnique({
    where: {
      tenant_id_user_id: {
        tenant_id: tenantId,
        user_id: userId,
      },
    },
  });

  if (!membership) {
    throw new Error('用户不是该租户的成员');
  }

  // 删除租户成员关系和模块权限
  await prisma.$transaction(async (tx) => {
    await tx.tenant_members.delete({
      where: { id: membership.id },
    });

    await tx.user_modules.deleteMany({
      where: {
        user_id: userId,
        tenant_id: tenantId,
      },
    });
  });

  logger.info('[UserService] Tenant removed from user', {
    userId,
    tenantId,
    removedBy: removerId,
  });
}

/**
 * 更新用户在指定租户的模块权限
 */
export async function updateUserModules(
  userId: string,
  data: UpdateUserModulesRequest,
  updaterId: string
): Promise<void> {
  // 检查用户是否是该租户成员
  const membership = await prisma.tenant_members.findUnique({
    where: {
      tenant_id_user_id: {
        tenant_id: data.tenantId,
        user_id: userId,
      },
    },
  });

  if (!membership) {
    throw new Error('用户不是该租户的成员');
  }

  // 获取租户订阅的模块
  const tenantModules = await prisma.tenant_modules.findMany({
    where: { tenant_id: data.tenantId, is_enabled: true },
  });
  const tenantModuleCodes = tenantModules.map((tm) => tm.module_code);

  // 验证请求的模块是否在租户订阅范围内
  const invalidModules = data.modules.filter((m) => !tenantModuleCodes.includes(m));
  if (invalidModules.length > 0) {
    throw new Error(`以下模块不在租户订阅范围内: ${invalidModules.join(', ')}`);
  }

  // 更新用户模块权限
  await prisma.$transaction(async (tx) => {
    // 删除旧的模块权限
    await tx.user_modules.deleteMany({
      where: {
        user_id: userId,
        tenant_id: data.tenantId,
      },
    });

    // 创建新的模块权限
    if (data.modules.length > 0) {
      await tx.user_modules.createMany({
        data: data.modules.map((moduleCode) => ({
          id: uuidv4(),
          user_id: userId,
          tenant_id: data.tenantId,
          module_code: moduleCode,
          is_enabled: true,
        })),
      });
    }
  });

  logger.info('[UserService] User modules updated', {
    userId,
    tenantId: data.tenantId,
    modules: data.modules,
    updatedBy: updaterId,
  });
}

/**
 * 批量导入用户
 */
export async function importUsers(
  rows: ImportUserRow[],
  defaultTenantId: string,
  importerId: string
): Promise<ImportResult> {
  const result: ImportResult = {
    success: 0,
    failed: 0,
    errors: [],
  };

  for (let i = 0; i < rows.length; i++) {
    const row = rows[i];
    const rowNumber = i + 2; // Excel行号（跳过表头）

    try {
      // 验证手机号
      if (!row.phone || !/^1[3-9]\d{9}$/.test(row.phone)) {
        throw new Error('手机号格式不正确');
      }

      // 验证姓名
      if (!row.name || row.name.trim().length === 0) {
        throw new Error('姓名不能为空');
      }

      // 解析角色
      const role = parseRole(row.role);

      // 解析租户
      let tenantId = defaultTenantId;
      if (row.tenantCode) {
        const tenant = await prisma.tenants.findUnique({
          where: { code: row.tenantCode },
        });
        if (!tenant) {
          throw new Error(`租户代码 ${row.tenantCode} 不存在`);
        }
        tenantId = tenant.id;
      }

      // 解析科室
      let departmentId: string | undefined;
      if (row.departmentName) {
        const department = await prisma.departments.findFirst({
          where: {
            name: row.departmentName,
            tenant_id: tenantId,
          },
        });
        if (!department) {
          throw new Error(`科室 ${row.departmentName} 不存在`);
        }
        departmentId = department.id;
      }

      // 解析模块
      const modules = row.modules
        ? row.modules.split(',').map((m) => m.trim().toUpperCase())
        : undefined;

      // 创建用户
      await createUser(
        {
          phone: row.phone,
          name: row.name.trim(),
          email: row.email,
          role,
          tenantId,
          departmentId,
          allowedModules: modules,
        },
        importerId
      );

      result.success++;
    } catch (error: any) {
      result.failed++;
      result.errors.push({
        row: rowNumber,
        phone: row.phone || '',
        error: error.message,
      });
    }
  }

  logger.info('[UserService] Batch import completed', {
    success: result.success,
    failed: result.failed,
    importedBy: importerId,
  });

  return result;
}

/**
 * 获取所有租户列表（用于下拉选择）
 */
export async function getAllTenants() {
  return prisma.tenants.findMany({
    where: { status: 'ACTIVE' },
    select: {
      id: true,
      code: true,
      name: true,
      type: true,
    },
    orderBy: { name: 'asc' },
  });
}

/**
 * 获取租户的科室列表（用于下拉选择）
 */
export async function getDepartmentsByTenant(tenantId: string) {
  return prisma.departments.findMany({
    where: { tenant_id: tenantId },
    select: {
      id: true,
      name: true,
      parent_id: true,
    },
    orderBy: { name: 'asc' },
  });
}

/**
 * 获取租户的模块列表（用于模块配置）
 */
export async function getModulesByTenant(tenantId: string) {
  const tenantModules = await prisma.tenant_modules.findMany({
    where: { tenant_id: tenantId, is_enabled: true },
  });

  const allModules = await prisma.modules.findMany({
    where: { is_active: true },
    orderBy: { sort_order: 'asc' },
  });

  return allModules.map((m) => ({
    code: m.code,
    name: m.name,
    isSubscribed: tenantModules.some((tm) => tm.module_code === m.code),
  }));
}

// ============ 辅助函数 ============

function getModuleName(code: string): string {
  const moduleNames: Record<string, string> = {
    AIA: 'AI智能问答',
    PKB: '个人知识库',
    ASL: 'AI智能文献',
    DC: '数据清洗整理',
    IIT: 'IIT Manager',
    RVW: '稿件审查',
    SSA: '智能统计分析',
    ST: '统计分析工具',
  };
  return moduleNames[code] || code;
}

function parseRole(roleStr?: string): UserRole {
  if (!roleStr) return 'USER';

  const roleMap: Record<string, UserRole> = {
    超级管理员: 'SUPER_ADMIN',
    SUPER_ADMIN: 'SUPER_ADMIN',
    PROMPT工程师: 'PROMPT_ENGINEER',
    PROMPT_ENGINEER: 'PROMPT_ENGINEER',
    医院管理员: 'HOSPITAL_ADMIN',
    HOSPITAL_ADMIN: 'HOSPITAL_ADMIN',
    药企管理员: 'PHARMA_ADMIN',
    PHARMA_ADMIN: 'PHARMA_ADMIN',
    科室主任: 'DEPARTMENT_ADMIN',
    DEPARTMENT_ADMIN: 'DEPARTMENT_ADMIN',
    普通用户: 'USER',
    USER: 'USER',
  };

  return roleMap[roleStr.trim()] || 'USER';
}