package handler

import (
	"strconv"

	"carrot_bbs/internal/dto"
	"carrot_bbs/internal/model"
	"carrot_bbs/internal/pkg/response"
	"carrot_bbs/internal/repository"
	"carrot_bbs/internal/service"

	"github.com/gin-gonic/gin"
)

type AdminVerificationHandler struct {
	adminVerificationService service.AdminVerificationService
	userRepo                 repository.UserRepository
}

func NewAdminVerificationHandler(
	adminVerificationService service.AdminVerificationService,
	userRepo repository.UserRepository,
) *AdminVerificationHandler {
	return &AdminVerificationHandler{
		adminVerificationService: adminVerificationService,
		userRepo:                 userRepo,
	}
}

func (h *AdminVerificationHandler) ListVerifications(c *gin.Context) {
	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	pageSize, _ := strconv.Atoi(c.DefaultQuery("page_size", "20"))
	status := c.Query("status")
	keyword := c.Query("keyword")

	if page <= 0 {
		page = 1
	}
	if pageSize <= 0 || pageSize > 100 {
		pageSize = 20
	}

	if status != "" && status != string(model.VerificationStatusPending) &&
		status != string(model.VerificationStatusApproved) &&
		status != string(model.VerificationStatusRejected) {
		response.BadRequest(c, "无效的状态值")
		return
	}

	records, total, err := h.adminVerificationService.ListVerifications(c.Request.Context(), page, pageSize, status, keyword)
	if err != nil {
		response.InternalServerError(c, "获取认证列表失败")
		return
	}

	responses := make([]*dto.AdminVerificationListResponse, len(records))
	for i, record := range records {
		responses[i] = h.convertToAdminListResponse(record)
	}

	response.Paginated(c, responses, total, page, pageSize)
}

func (h *AdminVerificationHandler) GetVerificationDetail(c *gin.Context) {
	id := c.Param("id")
	if id == "" {
		response.BadRequest(c, "认证ID不能为空")
		return
	}

	record, err := h.adminVerificationService.GetVerificationDetail(c.Request.Context(), id)
	if err != nil {
		response.NotFound(c, "认证记录不存在")
		return
	}

	response.Success(c, h.convertToAdminDetailResponse(record))
}

func (h *AdminVerificationHandler) ReviewVerification(c *gin.Context) {
	reviewerID, exists := c.Get("user_id")
	if !exists {
		response.Unauthorized(c, "未授权")
		return
	}

	id := c.Param("id")
	if id == "" {
		response.BadRequest(c, "认证ID不能为空")
		return
	}

	var req dto.AdminReviewVerificationRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误: "+err.Error())
		return
	}

	if !req.Approve && req.RejectReason == "" {
		response.BadRequest(c, "拒绝时必须填写拒绝原因")
		return
	}

	record, err := h.adminVerificationService.ReviewVerification(
		c.Request.Context(),
		reviewerID.(string),
		id,
		req.Approve,
		req.RejectReason,
	)
	if err != nil {
		response.HandleError(c, err, "审核失败")
		return
	}

	response.Success(c, h.convertToAdminDetailResponse(record))
}

func (h *AdminVerificationHandler) convertToAdminListResponse(record *model.VerificationRecord) *dto.AdminVerificationListResponse {
	resp := &dto.AdminVerificationListResponse{
		ID:         record.ID,
		UserID:     record.UserID,
		Identity:   string(record.Identity),
		Status:     string(record.Status),
		RealName:   record.RealName,
		StudentID:  record.StudentID,
		EmployeeID: record.EmployeeID,
		Department: record.Department,
		CreatedAt:  dto.FormatTime(record.CreatedAt),
	}

	user, err := h.userRepo.GetByID(record.UserID)
	if err == nil && user != nil {
		resp.Username = user.Username
		resp.Nickname = user.Nickname
		resp.Avatar = user.Avatar
	}

	if record.ReviewedAt != nil {
		resp.ReviewedAt = dto.FormatTime(*record.ReviewedAt)
		if record.ReviewedBy != nil {
			reviewer, err := h.userRepo.GetByID(*record.ReviewedBy)
			if err == nil && reviewer != nil {
				resp.ReviewerName = reviewer.Nickname
			}
		}
	}

	return resp
}

func (h *AdminVerificationHandler) convertToAdminDetailResponse(record *model.VerificationRecord) *dto.AdminVerificationDetailResponse {
	resp := &dto.AdminVerificationDetailResponse{
		ID:             record.ID,
		UserID:         record.UserID,
		Identity:       string(record.Identity),
		Status:         string(record.Status),
		RealName:       record.RealName,
		StudentID:      record.StudentID,
		EmployeeID:     record.EmployeeID,
		Department:     record.Department,
		ProofMaterials: record.ProofMaterials,
		CreatedAt:      dto.FormatTime(record.CreatedAt),
	}

	user, err := h.userRepo.GetByID(record.UserID)
	if err == nil && user != nil {
		resp.Username = user.Username
		resp.Nickname = user.Nickname
		resp.Avatar = user.Avatar
	}

	if record.ReviewedAt != nil {
		resp.ReviewedAt = dto.FormatTime(*record.ReviewedAt)
	}
	if record.ReviewedBy != nil {
		resp.ReviewedBy = *record.ReviewedBy
		if reviewer, err := h.userRepo.GetByID(*record.ReviewedBy); err == nil && reviewer != nil {
			resp.ReviewerName = reviewer.Nickname
		}
	}
	if record.RejectReason != "" {
		resp.RejectReason = record.RejectReason
	}

	return resp
}