package logic

import (
	"context"
	"database/sql"
	"fmt"
	"time"

	"git.cialloo.com/CiallooWeb/Blog/app/internal/svc"
	"git.cialloo.com/CiallooWeb/Blog/app/internal/types"

	"github.com/aws/aws-sdk-go-v2/service/s3"
	"github.com/zeromicro/go-zero/core/logx"
)

type GetPostLogic struct {
	logx.Logger
	ctx    context.Context
	svcCtx *svc.ServiceContext
}

// Get a blog post by ID
func NewGetPostLogic(ctx context.Context, svcCtx *svc.ServiceContext) *GetPostLogic {
	return &GetPostLogic{
		Logger: logx.WithContext(ctx),
		ctx:    ctx,
		svcCtx: svcCtx,
	}
}

func (l *GetPostLogic) GetPost(req *types.GetPostReq) (resp *types.GetPostResp, err error) {
	var post types.GetPostResp
	var coverID sql.NullInt64

	// Query post with cover image
	query := `
		SELECT p.id, p.title, p.content, p.created_at, p.updated_at, p.cover_id
		FROM posts p
		WHERE p.id = $1
	`
	err = l.svcCtx.DB.QueryRowContext(l.ctx, query, req.PostId).Scan(
		&post.PostId, &post.Title, &post.Content, &post.CreatedAt, &post.UpdatedAt, &coverID,
	)
	if err != nil {
		if err == sql.ErrNoRows {
			l.Errorf("Post not found with id: %s", req.PostId)
			return nil, fmt.Errorf("post not found")
		}
		l.Errorf("Failed to get post: %v", err)
		return nil, err
	}

	// If cover image exists, get its URL
	if coverID.Valid {
		coverQuery := `SELECT file_key FROM files WHERE id = $1`
		var fileKey string
		err = l.svcCtx.DB.QueryRowContext(l.ctx, coverQuery, coverID.Int64).Scan(&fileKey)
		if err == nil {
			// Generate presigned URL for cover image
			expiration := time.Duration(l.svcCtx.Config.S3.PresignedURLExpiration) * time.Second
			presignClient := s3.NewPresignClient(l.svcCtx.S3Client)
			getObjectInput := &s3.GetObjectInput{
				Bucket: &l.svcCtx.Config.S3.Bucket,
				Key:    &fileKey,
			}
			presignedReq, err := presignClient.PresignGetObject(l.ctx, getObjectInput, func(opts *s3.PresignOptions) {
				opts.Expires = expiration
			})
			if err == nil {
				post.CoverImageUrl = presignedReq.URL
			}
		}
	}

	// Convert timestamps to Unix
	post.CreatedAt = post.CreatedAt * 1000 // Convert to milliseconds if needed
	post.UpdatedAt = post.UpdatedAt * 1000

	return &post, nil
}