package repository

import (
	"context"

	"gorm.io/gorm"

	"github.com/gochat/gochat/internal/model"
)

// DraftMessageRepo implements GORM repository for DraftMessage.
// Reference: Chatwoot app/models/draft_message.rb
type DraftMessageRepo struct {
	db *gorm.DB
}

// NewDraftMessageRepo creates a new DraftMessage repository.
func NewDraftMessageRepo(db *gorm.DB) *DraftMessageRepo {
	return &DraftMessageRepo{db: db}
}

// FindByConversationID retrieves all draft messages for a conversation, optionally filtered by user.
func (r *DraftMessageRepo) FindByConversationID(ctx context.Context, conversationID uint, userID uint) ([]model.DraftMessage, error) {
	var drafts []model.DraftMessage
	query := r.db.WithContext(ctx).Where("conversation_id = ?", conversationID)
	if userID > 0 {
		query = query.Where("user_id = ?", userID)
	}
	err := query.Order("id DESC").Find(&drafts).Error
	return drafts, err
}

// FindByID retrieves a draft message by ID.
func (r *DraftMessageRepo) FindByID(ctx context.Context, id uint) (*model.DraftMessage, error) {
	var draft model.DraftMessage
	err := r.db.WithContext(ctx).First(&draft, id).Error
	if err != nil {
		return nil, err
	}
	return &draft, nil
}

// Create creates a new draft message.
func (r *DraftMessageRepo) Create(ctx context.Context, draft *model.DraftMessage) error {
	return r.db.WithContext(ctx).Create(draft).Error
}

// Update updates an existing draft message.
func (r *DraftMessageRepo) Update(ctx context.Context, draft *model.DraftMessage) error {
	return r.db.WithContext(ctx).Save(draft).Error
}

// Delete deletes a draft message.
func (r *DraftMessageRepo) Delete(ctx context.Context, id uint) error {
	return r.db.WithContext(ctx).Delete(&model.DraftMessage{}, id).Error
}

// SearchByContent retrieves draft messages whose content matches the given query string (LIKE).
func (r *DraftMessageRepo) SearchByContent(ctx context.Context, accountID uint, query string) ([]model.DraftMessage, error) {
	var drafts []model.DraftMessage
	// Join through conversations to filter by account_id
	err := r.db.WithContext(ctx).
		Joins("JOIN conversations ON conversations.id = draft_messages.conversation_id").
		Where("conversations.account_id = ?", accountID).
		Where("draft_messages.content LIKE ?", "%"+query+"%").
		Order("draft_messages.id DESC").
		Find(&drafts).Error
	return drafts, err
}

// CountByAccount returns the total number of draft messages for an account.
func (r *DraftMessageRepo) CountByAccount(ctx context.Context, accountID uint) (int64, error) {
	var count int64
	err := r.db.WithContext(ctx).
		Joins("JOIN conversations ON conversations.id = draft_messages.conversation_id").
		Where("conversations.account_id = ?", accountID).
		Count(&count).Error
	return count, err
}