package social

import (
	"context"
	"errors"

	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgxpool"

	"shared-album/internal/models"
)

var ErrNotFound = errors.New("not found")

type Store struct {
	pool *pgxpool.Pool
}

func NewStore(pool *pgxpool.Pool) *Store { return &Store{pool: pool} }

func (s *Store) Like(ctx context.Context, photoID, userID string) error {
	_, err := s.pool.Exec(ctx,
		`INSERT INTO likes (photo_id, user_id) VALUES ($1, $2)
		 ON CONFLICT (photo_id, user_id) DO NOTHING`, photoID, userID)
	return err
}

func (s *Store) Unlike(ctx context.Context, photoID, userID string) error {
	_, err := s.pool.Exec(ctx,
		`DELETE FROM likes WHERE photo_id = $1 AND user_id = $2`, photoID, userID)
	return err
}

func (s *Store) CreateComment(ctx context.Context, c *models.Comment) error {
	return s.pool.QueryRow(ctx,
		`INSERT INTO comments (id, photo_id, user_id, text)
		 VALUES ($1, $2, $3, $4)
		 RETURNING created_at, updated_at`,
		c.ID, c.PhotoID, c.UserID, c.Text,
	).Scan(&c.CreatedAt, &c.UpdatedAt)
}

func (s *Store) ListComments(ctx context.Context, photoID string) ([]models.Comment, error) {
	rows, err := s.pool.Query(ctx,
		`SELECT c.id, c.photo_id, c.user_id, c.text, c.created_at, c.updated_at,
		        u.id, u.name, COALESCE(u.avatar_url, '')
		 FROM comments c
		 JOIN users u ON u.id = c.user_id
		 WHERE c.photo_id = $1
		 ORDER BY c.created_at`, photoID)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	out := []models.Comment{}
	for rows.Next() {
		var c models.Comment
		if err := rows.Scan(&c.ID, &c.PhotoID, &c.UserID, &c.Text, &c.CreatedAt, &c.UpdatedAt,
			&c.User.ID, &c.User.Name, &c.User.AvatarURL); err != nil {
			return nil, err
		}
		out = append(out, c)
	}
	return out, rows.Err()
}

func (s *Store) GetComment(ctx context.Context, id string) (*models.Comment, error) {
	var c models.Comment
	err := s.pool.QueryRow(ctx,
		`SELECT id, photo_id, user_id, text, created_at, updated_at FROM comments WHERE id = $1`, id).
		Scan(&c.ID, &c.PhotoID, &c.UserID, &c.Text, &c.CreatedAt, &c.UpdatedAt)
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return nil, ErrNotFound
		}
		return nil, err
	}
	return &c, nil
}

func (s *Store) DeleteComment(ctx context.Context, id string) error {
	tag, err := s.pool.Exec(ctx, `DELETE FROM comments WHERE id = $1`, id)
	if err != nil {
		return err
	}
	if tag.RowsAffected() == 0 {
		return ErrNotFound
	}
	return nil
}