package database

import (
	"context"
	"path/filepath"
	"testing"
)

func TestOpenAppliesPragmasAndMigrates(t *testing.T) {
	ctx := context.Background()
	path := filepath.Join(t.TempDir(), "db", "glchat.db")

	db, err := Open(ctx, Options{Path: path, ReadPool: 2, Migrate: true})
	if err != nil {
		t.Fatalf("Open() returned error: %v", err)
	}
	defer db.Close()

	journal, err := db.JournalMode(ctx)
	if err != nil {
		t.Fatalf("JournalMode() returned error: %v", err)
	}
	if journal != "wal" {
		t.Errorf("journal mode = %q, want wal", journal)
	}

	version, err := db.SchemaVersion(ctx)
	if err != nil {
		t.Fatalf("SchemaVersion() returned error: %v", err)
	}
	if version < 1 {
		t.Errorf("schema version = %d, want >= 1", version)
	}

	var foreignKeys int
	if err := db.Writer.QueryRowContext(ctx, "PRAGMA foreign_keys").Scan(&foreignKeys); err != nil {
		t.Fatalf("read foreign_keys pragma: %v", err)
	}
	if foreignKeys != 1 {
		t.Errorf("foreign_keys = %d, want 1", foreignKeys)
	}

	var baseline string
	if err := db.Reader.QueryRowContext(ctx,
		`SELECT value FROM instance_settings WHERE key = 'registration_enabled'`,
	).Scan(&baseline); err != nil {
		t.Fatalf("read instance setting: %v", err)
	}
	if baseline != "true" {
		t.Errorf("registration_enabled = %q, want true", baseline)
	}
}

func TestMigrateIsIdempotent(t *testing.T) {
	ctx := context.Background()
	path := filepath.Join(t.TempDir(), "glchat.db")

	db, err := Open(ctx, Options{Path: path, ReadPool: 2, Migrate: true})
	if err != nil {
		t.Fatalf("first Open() returned error: %v", err)
	}
	if err := db.Migrate(ctx); err != nil {
		t.Fatalf("second Migrate() returned error: %v", err)
	}

	var applied int
	if err := db.Reader.QueryRowContext(ctx,
		`SELECT COUNT(*) FROM goose_db_version WHERE version_id = 1 AND is_applied = 1`,
	).Scan(&applied); err != nil {
		t.Fatalf("count applied migrations: %v", err)
	}
	if applied != 1 {
		t.Errorf("migration 1 applied %d times, want 1", applied)
	}

	// Baseline-миграция должна применяться ровно один раз, независимо от их числа.
	version, err := db.SchemaVersion(ctx)
	if err != nil {
		t.Fatalf("SchemaVersion: %v", err)
	}
	if version < 2 {
		t.Errorf("schema version = %d, want >= 2 after phase 1 migration", version)
	}
	if err := db.Close(); err != nil {
		t.Fatalf("Close() returned error: %v", err)
	}
}

func TestOpenRejectsEmptyPath(t *testing.T) {
	if _, err := Open(context.Background(), Options{}); err == nil {
		t.Fatal("Open() accepted an empty path")
	}
}

func TestReadyFailsOnClosedDatabase(t *testing.T) {
	ctx := context.Background()
	db, err := Open(ctx, Options{Path: filepath.Join(t.TempDir(), "glchat.db"), Migrate: true})
	if err != nil {
		t.Fatalf("Open() returned error: %v", err)
	}
	if err := db.Close(); err != nil {
		t.Fatalf("Close() returned error: %v", err)
	}
	if err := db.Ready(ctx); err == nil {
		t.Fatal("Ready() returned nil for a closed database")
	}
}