// internal/services/claim_service.go
package services

import (
	"errors"
	"lost-and-found/internal/models"
	"lost-and-found/internal/repositories"

	"gorm.io/gorm"
)

type ClaimService struct {
	db               *gorm.DB // Tambahkan ini
	claimRepo        *repositories.ClaimRepository
	itemRepo         *repositories.ItemRepository
	verificationRepo *repositories.ClaimVerificationRepository
	notificationRepo *repositories.NotificationRepository
	auditLogRepo     *repositories.AuditLogRepository
}

func NewClaimService(db *gorm.DB) *ClaimService {
	return &ClaimService{
		db:               db, // Tambahkan ini
		claimRepo:        repositories.NewClaimRepository(db),
		itemRepo:         repositories.NewItemRepository(db),
		verificationRepo: repositories.NewClaimVerificationRepository(db),
		notificationRepo: repositories.NewNotificationRepository(db),
		auditLogRepo:     repositories.NewAuditLogRepository(db),
	}
}

// CreateClaimRequest represents claim creation data
type CreateClaimRequest struct {
	ItemID      uint   `json:"item_id" binding:"required"`
	Description string `json:"description" binding:"required"`
	ProofURL    string `json:"proof_url"`
	Contact     string `json:"contact" binding:"required"`
}

// VerifyClaimRequest represents claim verification data
type VerifyClaimRequest struct {
	Status string `json:"status" binding:"required"` // approved or rejected
	Notes  string `json:"notes"`
}

// CreateClaim creates a new claim
func (s *ClaimService) CreateClaim(userID uint, req CreateClaimRequest, ipAddress, userAgent string) (*models.Claim, error) {
	// Check if item exists
	item, err := s.itemRepo.FindByID(req.ItemID)
	if err != nil {
		return nil, err
	}

	// Check if item can be claimed
	if !item.CanBeClaimed() {
		return nil, errors.New("item cannot be claimed")
	}

	// Check if user already claimed this item
	exists, err := s.claimRepo.CheckExistingClaim(userID, req.ItemID)
	if err != nil {
		return nil, err
	}
	if exists {
		return nil, errors.New("you already claimed this item")
	}

	// Create claim
	claim := &models.Claim{
		ItemID:      req.ItemID,
		UserID:      userID,
		Description: req.Description,
		ProofURL:    req.ProofURL,
		Contact:     req.Contact,
		Status:      models.ClaimStatusPending,
	}

	if err := s.claimRepo.Create(claim); err != nil {
		return nil, errors.New("failed to create claim")
	}

	// Update item status to pending claim
	s.itemRepo.UpdateStatus(req.ItemID, models.ItemStatusPendingClaim)

	// Log audit
	s.auditLogRepo.Log(&userID, models.ActionCreate, models.EntityClaim, &claim.ID,
		"Claim created for item: "+item.Name, ipAddress, userAgent)

	// Load claim with relations
	return s.claimRepo.FindByID(claim.ID)
}

// GetAllClaims gets all claims
func (s *ClaimService) GetAllClaims(page, limit int, status string, itemID, userID *uint) ([]models.ClaimResponse, int64, error) {
	claims, total, err := s.claimRepo.FindAll(page, limit, status, itemID, userID)
	if err != nil {
		return nil, 0, err
	}

	var responses []models.ClaimResponse
	for _, claim := range claims {
		responses = append(responses, claim.ToResponse())
	}

	return responses, total, nil
}

// GetClaimByID gets claim by ID
func (s *ClaimService) GetClaimByID(id uint, isManager bool) (interface{}, error) {
	claim, err := s.claimRepo.FindByID(id)
	if err != nil {
		return nil, err
	}

	// Manager can see full details including item description
	if isManager {
		return claim.ToDetailResponse(), nil
	}

	return claim.ToResponse(), nil
}

// GetClaimsByUser gets claims by user
func (s *ClaimService) GetClaimsByUser(userID uint, page, limit int) ([]models.ClaimResponse, int64, error) {
	claims, total, err := s.claimRepo.FindByUser(userID, page, limit)
	if err != nil {
		return nil, 0, err
	}

	var responses []models.ClaimResponse
	for _, claim := range claims {
		responses = append(responses, claim.ToResponse())
	}

	return responses, total, nil
}

// VerifyClaim verifies a claim (manager only)
func (s *ClaimService) VerifyClaim(managerID, claimID uint, req VerifyClaimRequest, similarityScore float64, matchedKeywords string, ipAddress, userAgent string) error {
	claim, err := s.claimRepo.FindByID(claimID)
	if err != nil {
		return err
	}

	if !claim.IsPending() {
		return errors.New("claim is not pending")
	}

	// Create or update verification record
	verification, _ := s.verificationRepo.FindByClaimID(claimID)
	if verification == nil {
		verification = &models.ClaimVerification{
			ClaimID:           claimID,
			SimilarityScore:   similarityScore,
			MatchedKeywords:   matchedKeywords,
			VerificationNotes: req.Notes,
			IsAutoMatched:     false,
		}
		s.verificationRepo.Create(verification)
	} else {
		verification.VerificationNotes = req.Notes
		s.verificationRepo.Update(verification)
	}

	// Update claim status
	if req.Status == models.ClaimStatusApproved {
		claim.Approve(managerID, req.Notes)
		
		// Update item status to verified
		s.itemRepo.UpdateStatus(claim.ItemID, models.ItemStatusVerified)
		
		// Send approval notification - PERBAIKAN DI SINI
		item, _ := s.itemRepo.FindByID(claim.ItemID)
		models.CreateClaimApprovedNotification(s.db, claim.UserID, item.Name, claimID)
		
		// Log audit
		s.auditLogRepo.Log(&managerID, models.ActionApprove, models.EntityClaim, &claimID,
			"Claim approved", ipAddress, userAgent)
	} else if req.Status == models.ClaimStatusRejected {
		claim.Reject(managerID, req.Notes)
		
		// Check if there are other pending claims for this item
		otherClaims, _ := s.claimRepo.FindByItem(claim.ItemID)
		hasPendingClaims := false
		for _, c := range otherClaims {
			if c.ID != claimID && c.IsPending() {
				hasPendingClaims = true
				break
			}
		}
		
		// If no other pending claims, set item back to unclaimed
		if !hasPendingClaims {
			s.itemRepo.UpdateStatus(claim.ItemID, models.ItemStatusUnclaimed)
		}
		
		// Send rejection notification - PERBAIKAN DI SINI
		item, _ := s.itemRepo.FindByID(claim.ItemID)
		models.CreateClaimRejectedNotification(s.db, claim.UserID, item.Name, req.Notes, claimID)
		
		// Log audit
		s.auditLogRepo.Log(&managerID, models.ActionReject, models.EntityClaim, &claimID,
			"Claim rejected: "+req.Notes, ipAddress, userAgent)
	} else {
		return errors.New("invalid status")
	}

	if err := s.claimRepo.Update(claim); err != nil {
		return errors.New("failed to verify claim")
	}

	return nil
}

// CloseClaim closes a claim and moves item to archive (manager only)
func (s *ClaimService) CloseClaim(managerID, claimID uint, ipAddress, userAgent string) error {
	claim, err := s.claimRepo.FindByID(claimID)
	if err != nil {
		return err
	}

	if !claim.IsApproved() {
		return errors.New("only approved claims can be closed")
	}

	// Update item status to case_closed
	if err := s.itemRepo.UpdateStatus(claim.ItemID, models.ItemStatusCaseClosed); err != nil {
		return errors.New("failed to close case")
	}

	// Archive the item
	item, _ := s.itemRepo.FindByID(claim.ItemID)
	s.itemRepo.ArchiveItem(item, models.ArchiveReasonCaseClosed, &claim.UserID)

	// Log audit
	s.auditLogRepo.Log(&managerID, models.ActionUpdate, models.EntityItem, &item.ID,
		"Case closed and archived", ipAddress, userAgent)

	return nil
}

// DeleteClaim deletes a claim
func (s *ClaimService) DeleteClaim(userID, claimID uint, ipAddress, userAgent string) error {
	claim, err := s.claimRepo.FindByID(claimID)
	if err != nil {
		return err
	}

	// Only pending claims can be deleted by users
	if !claim.IsPending() && claim.UserID == userID {
		return errors.New("cannot delete non-pending claim")
	}

	if err := s.claimRepo.Delete(claimID); err != nil {
		return errors.New("failed to delete claim")
	}

	// Check if item should go back to unclaimed
	otherClaims, _ := s.claimRepo.FindByItem(claim.ItemID)
	if len(otherClaims) == 0 {
		s.itemRepo.UpdateStatus(claim.ItemID, models.ItemStatusUnclaimed)
	}

	// Log audit
	s.auditLogRepo.Log(&userID, models.ActionDelete, models.EntityClaim, &claimID,
		"Claim deleted", ipAddress, userAgent)

	return nil
}