package main

import (
	"context"
	"database/sql"
	"errors"
	"io"
	"os"
	"path/filepath"
	"runtime"
	"testing"
)

func TestRunUp(t *testing.T) {
	databaseSource := filepath.Join(t.TempDir(), "migrate.db")
	if err := run(context.Background(), []string{
		"-database", databaseSource,
		"-dir", migrationDirectory(t),
		"up",
	}, io.Discard); err != nil {
		t.Fatalf("run up migration command: %v", err)
	}

	database, err := sql.Open("sqlite3", databaseSource)
	if err != nil {
		t.Fatalf("open migrated database: %v", err)
	}
	t.Cleanup(func() {
		if err := database.Close(); err != nil {
			t.Errorf("close migrated database: %v", err)
		}
	})

	var count int
	if err := database.QueryRow(`SELECT COUNT(*) FROM sqlite_master WHERE type = 'table' AND name = 'tasks'`).Scan(&count); err != nil {
		t.Fatalf("look up tasks table: %v", err)
	}
	if count != 1 {
		t.Fatalf("tasks table count = %d, want 1", count)
	}
}

func TestRunRequiresDatabase(t *testing.T) {
	if err := run(context.Background(), []string{"up"}, io.Discard); err == nil {
		t.Fatal("run without database source succeeded")
	}
}

func TestRunRejectsUndeclaredCommand(t *testing.T) {
	databaseSource := filepath.Join(t.TempDir(), "migrate.db")
	err := run(context.Background(), []string{"-database", databaseSource, "reset"}, io.Discard)
	if err == nil {
		t.Fatal("run with undeclared command succeeded")
	}
	if _, err := os.Stat(databaseSource); !errors.Is(err, os.ErrNotExist) {
		t.Fatalf("undeclared command opened database source: stat error = %v, want not exist", err)
	}
}

func migrationDirectory(t *testing.T) string {
	t.Helper()
	_, file, _, ok := runtime.Caller(0)
	if !ok {
		t.Fatal("locate migration command test source")
	}

	return filepath.Join(filepath.Dir(file), "..", "..", "migrations")
}