Implement task management commands: add, list, done, undo, remove

main.go

@@ -38,15 +38,118 @@ func init() {
 		log.Fatal("Unable to ping database:", err)
 	}
 
-	fmt.Println("Connected to PostgreSQL database!")
+	// fmt.Println("Connected to PostgreSQL database!")
 }
 
 func main() {
 	app := &cli.App{
-		Name:     "Go Todo App",
+		Name:  "gotodo",
 		Usage: "A simple CLI program to manage your tasks",
+		Action: func(c *cli.Context) error {
+			tasks, err := getPendingTasks()
+			if err != nil {
+				return err
+			}
+
+			fmt.Println("Pending Tasks:")
+			printTasks(tasks)
+			return nil
+		},
 		Commands: []*cli.Command{
-			// We'll add commands here
+			{
+				Name:    "add",
+				Aliases: []string{"a"},
+				Usage:   "Add a new task",
+				Action: func(c *cli.Context) error {
+					text := c.Args().First()
+					if text == "" {
+						return fmt.Errorf("task text cannot be empty")
+					}
+					return createTask(text)
+				},
+			},
+			{
+				Name:    "list",
+				Aliases: []string{"ls"},
+				Usage:   "List tasks with filters",
+				Flags: []cli.Flag{
+					&cli.BoolFlag{Name: "all", Aliases: []string{"a"}, Usage: "List all tasks"},
+					&cli.BoolFlag{Name: "completed", Aliases: []string{"c"}, Usage: "List only completed tasks"},
+					&cli.BoolFlag{Name: "pending", Aliases: []string{"p"}, Usage: "List only pending tasks"},
+				},
+				Action: func(c *cli.Context) error {
+					var tasks []Task
+					var err error
+					title := "Pending Tasks:"
+
+					if c.Bool("all") {
+						tasks, err = getAllTasks()
+						title = "All Tasks:"
+					} else if c.Bool("completed") {
+						tasks, err = getCompletedTasks()
+						title = "Completed Tasks:"
+					} else {
+						tasks, err = getPendingTasks()
+						title = "Pending Tasks:"
+					}
+
+					if err != nil {
+						return err
+					}
+
+					fmt.Println(title)
+					printTasks(tasks)
+					return nil
+				},
+			},
+			{
+				Name:    "done",
+				Aliases: []string{"do"},
+				Usage:   "Mark a task as completed",
+				Action: func(c *cli.Context) error {
+					idStr := c.Args().First()
+					if idStr == "" {
+						return fmt.Errorf("task ID required")
+					}
+					var id int
+					if _, err := fmt.Sscanf(idStr, "%d", &id); err != nil {
+						return fmt.Errorf("invalid task ID: %s", idStr)
+					}
+					return completeTask(id)
+				},
+			},
+			{
+				Name:    "undo",
+				Aliases: []string{"ud"},
+				Usage:   "Mark a task as not completed",
+				Action: func(c *cli.Context) error {
+					idStr := c.Args().First()
+					if idStr == "" {
+						return fmt.Errorf("task ID required")
+					}
+					var id int
+					if _, err := fmt.Sscanf(idStr, "%d", &id); err != nil {
+						return fmt.Errorf("invalid task ID: %s", idStr)
+					}
+					return undoTask(id)
+				},
+			},
+			{
+				Name:    "remove",
+				Aliases: []string{"rm"},
+				Usage:   "Remove a task",
+				Action: func(c *cli.Context) error {
+					idStr := c.Args().First()
+					if idStr == "" {
+						return fmt.Errorf("task ID required")
+					}
+					var id int
+					if _, err := fmt.Sscanf(idStr, "%d", &id); err != nil {
+						return fmt.Errorf("invalid task ID: %s", idStr)
+					}
+					return deleteTask(id)
+				},
+			},
 		},
 	}
 
@@ -55,3 +158,202 @@ func main() {
 		log.Fatal(err)
 	}
 }
+
+func createTask(text string) error {
+	sql := `
+		INSERT INTO tasks (text, completed)
+		VALUES ($1, $2)
+		RETURNING id
+	`
+
+	var id int
+	err := pool.QueryRow(ctx, sql, text, false).Scan(&id)
+	if err != nil {
+		return fmt.Errorf("error creating task: %w", err)
+	}
+
+	fmt.Printf("Created task with ID: %d\n", id)
+	return nil
+}
+
+func getAllTasks() ([]Task, error) {
+	sql := `
+		SELECT id, text, completed, created_at, updated_at
+		FROM tasks
+		ORDER BY created_at DESC
+	`
+
+	rows, err := pool.Query(ctx, sql)
+	if err != nil {
+		return nil, fmt.Errorf("error querying tasks: %w", err)
+	}
+	defer rows.Close()
+
+	var tasks []Task
+	for rows.Next() {
+		var task Task
+		err := rows.Scan(
+			&task.Id,
+			&task.Text,
+			&task.Completed,
+			&task.CreatedAt,
+			&task.UpdatedAt,
+		)
+		if err != nil {
+			return nil, fmt.Errorf("error scanning task row: %w", err)
+		}
+		tasks = append(tasks, task)
+	}
+
+	if err := rows.Err(); err != nil {
+		return nil, fmt.Errorf("error iterating task rows: %w", err)
+	}
+
+	return tasks, nil
+}
+
+func completeTask(id int) error {
+	sql := `
+		UPDATE tasks
+		SET completed = true, updated_at = NOW()
+		WHERE id = $1
+	`
+
+	commandTag, err := pool.Exec(ctx, sql, id)
+	if err != nil {
+		return fmt.Errorf("error completing task: %w", err)
+	}
+
+	if commandTag.RowsAffected() == 0 {
+		return fmt.Errorf("no task found with id %d", id)
+	}
+
+	return nil
+}
+
+func undoTask(id int) error {
+	sql := `
+		UPDATE tasks
+		SET completed = false, updated_at = NOW()
+		WHERE id = $1
+	`
+
+	commandTag, err := pool.Exec(ctx, sql, id)
+	if err != nil {
+		return fmt.Errorf("error updating task: %w", err)
+	}
+
+	if commandTag.RowsAffected() == 0 {
+		return fmt.Errorf("no task found with id %d", id)
+	}
+
+	return nil
+}
+
+func deleteTask(id int) error {
+	sql := `DELETE FROM tasks WHERE id = $1`
+
+	commandTag, err := pool.Exec(ctx, sql, id)
+	if err != nil {
+		return fmt.Errorf("error deleting task: %w", err)
+	}
+
+	if commandTag.RowsAffected() == 0 {
+		return fmt.Errorf("no task found with id %d", id)
+	}
+
+	return nil
+}
+
+func getPendingTasks() ([]Task, error) {
+	sql := `
+		SELECT id, text, completed, created_at, updated_at
+		FROM tasks
+		WHERE completed = false
+		ORDER BY created_at DESC
+	`
+
+	rows, err := pool.Query(ctx, sql)
+	if err != nil {
+		return nil, fmt.Errorf("error querying pending tasks: %w", err)
+	}
+	defer rows.Close()
+
+	var tasks []Task
+	for rows.Next() {
+		var task Task
+		err := rows.Scan(
+			&task.Id,
+			&task.Text,
+			&task.Completed,
+			&task.CreatedAt,
+			&task.UpdatedAt,
+		)
+		if err != nil {
+			return nil, fmt.Errorf("error scanning task row: %w", err)
+		}
+		tasks = append(tasks, task)
+	}
+
+	if err := rows.Err(); err != nil {
+		return nil, fmt.Errorf("error iterating task rows: %w", err)
+	}
+
+	return tasks, nil
+}
+
+func getCompletedTasks() ([]Task, error) {
+	sql := `
+		SELECT id, text, completed, created_at, updated_at
+		FROM tasks
+		WHERE completed = true
+		ORDER BY created_at DESC
+	`
+
+	rows, err := pool.Query(ctx, sql)
+	if err != nil {
+		return nil, fmt.Errorf("error querying completed tasks: %w", err)
+	}
+	defer rows.Close()
+
+	var tasks []Task
+	for rows.Next() {
+		var task Task
+		err := rows.Scan(
+			&task.Id,
+			&task.Text,
+			&task.Completed,
+			&task.CreatedAt,
+			&task.UpdatedAt,
+		)
+		if err != nil {
+			return nil, fmt.Errorf("error scanning task row: %w", err)
+		}
+		tasks = append(tasks, task)
+	}
+
+	if err := rows.Err(); err != nil {
+		return nil, fmt.Errorf("error iterating task rows: %w", err)
+	}
+
+	return tasks, nil
+}
+
+func printTasks(tasks []Task) {
+	if len(tasks) == 0 {
+		fmt.Println("No tasks found")
+		return
+	}
+
+	for _, task := range tasks {
+		status := "[ ]"
+		if task.Completed {
+			status = "[✓]"
+		}
+		fmt.Printf("%d. %s %s (Created: %s)\n",
+			task.Id,
+			status,
+			task.Text,
+			task.CreatedAt.Format("2006-01-02 15:04:05"))
+	}
+}