package handlers

import (
	"net/http"
	"strconv"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"

	apperrors "veza-backend-api/internal/errors"
	"veza-backend-api/internal/services"
)

// ReportHandler handles moderation report endpoints (v0.803 ADM1)
type ReportHandler struct {
	reportService *services.ReportService
}

// NewReportHandler creates a new ReportHandler
func NewReportHandler(reportService *services.ReportService) *ReportHandler {
	return &ReportHandler{reportService: reportService}
}

// ListReports returns paginated reports (admin only)
func (h *ReportHandler) ListReports(c *gin.Context) {
	status := c.DefaultQuery("status", "all")
	limit, _ := strconv.Atoi(c.DefaultQuery("limit", "20"))
	limit = clampLimit(limit) // SECURITY(MEDIUM-004)
	offset, _ := strconv.Atoi(c.DefaultQuery("offset", "0"))

	reports, total, err := h.reportService.List(c.Request.Context(), services.ListReportsParams{
		Status: status,
		Limit:  limit,
		Offset: offset,
	})
	if err != nil {
		RespondWithAppError(c, apperrors.NewInternalErrorWrap("Failed to list reports", err))
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"reports": reports,
		"pagination": gin.H{
			"total":  total,
			"limit":  limit,
			"offset": offset,
		},
	})
}

// ResolveReport resolves a report (admin only)
func (h *ReportHandler) ResolveReport(c *gin.Context) {
	reportIDStr := c.Param("id")
	reportID, err := uuid.Parse(reportIDStr)
	if err != nil {
		RespondWithAppError(c, apperrors.NewValidationError("Invalid report ID"))
		return
	}

	userID, ok := GetUserIDUUID(c)
	if !ok || userID == uuid.Nil {
		RespondWithAppError(c, apperrors.NewUnauthorizedError("Authentication required"))
		return
	}

	var req services.ResolveReportRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		RespondWithAppError(c, apperrors.NewValidationError("action is required"))
		return
	}

	if err := h.reportService.Resolve(c.Request.Context(), reportID, userID, req.Action); err != nil {
		RespondWithAppError(c, apperrors.NewInternalErrorWrap("Failed to resolve report", err))
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "Report resolved"})
}

// CreateReport creates a report (authenticated user)
func (h *ReportHandler) CreateReport(c *gin.Context) {
	userID, ok := GetUserIDUUID(c)
	if !ok || userID == uuid.Nil {
		RespondWithAppError(c, apperrors.NewUnauthorizedError("Authentication required"))
		return
	}

	var req services.CreateReportRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		RespondWithAppError(c, apperrors.NewValidationError("content_type and reason are required"))
		return
	}

	report, err := h.reportService.Create(c.Request.Context(), userID, req)
	if err != nil {
		RespondWithAppError(c, apperrors.NewInternalErrorWrap("Failed to create report", err))
		return
	}

	c.JSON(http.StatusCreated, report)
}