db.go

package main

import (
	"context"

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

type Storage struct {
	db *pgxpool.Pool
}

type Task struct {
	ID    int    `json:"id"`
	Title string `json:"title"`
	Done  bool   `json:"done"`
}

func NewStorage(pool *pgxpool.Pool) *Storage {
	return &Storage{db: pool}
}

func (s *Storage) CreateTask(ctx context.Context, title string) (Task, error) {
	var task Task
	err := s.db.QueryRow(ctx,
		"INSERT INTO tasks (title) VALUES ($1) RETURNING id, title, done",
		title,
	).Scan(&task.ID, &task.Title, &task.Done)

	return task, err
}

func (s *Storage) PrintTask(ctx context.Context, id int) (Task, error) {
	var task Task
	err := s.db.QueryRow(ctx,
		"SELECT id, title, done FROM tasks WHERE id = $1",
		id,
	).Scan(&task.ID, &task.Title, &task.Done)

	return task, err
}

func (s *Storage) UpdateTask(ctx context.Context, id int, title string, done bool) (Task, error) {
	var task Task
	err := s.db.QueryRow(ctx,
		"UPDATE tasks SET title = $1, done = $2 WHERE id = $3 RETURNING id, title, done",
		title, done, id,
	).Scan(&task.ID, &task.Title, &task.Done)

	return task, err
}

func (s *Storage) PrintAllTasks(ctx context.Context) ([]Task, error) {
	rows, err := s.db.Query(ctx, "SELECT id, title, done FROM tasks")
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var tasks []Task
	for rows.Next() {
		var task Task
		if err := rows.Scan(&task.ID, &task.Title, &task.Done); err != nil {
			return nil, err
		}
		tasks = append(tasks, task)
	}

	if err := rows.Err(); err != nil {
		return nil, err
	}

	return tasks, nil
}

func (s *Storage) DeleteTask(ctx context.Context, id int) error {
	_, err := s.db.Exec(ctx,
		"DELETE FROM tasks WHERE id = $1",
		id,
	)
	return err
}