package database

import (
	"testing"
	"time"

	"github.com/prometheus/client_golang/prometheus"
)

func TestDefaultConfigOptions(t *testing.T) {
	opts := DefaultConfigOptions()

	// Verify expected defaults for API package
	if opts.MaxOpenConns != 25 {
		t.Errorf("Expected MaxOpenConns=25, got %d", opts.MaxOpenConns)
	}
	if opts.MaxIdleConns != 10 {
		t.Errorf("Expected MaxIdleConns=10, got %d", opts.MaxIdleConns)
	}
	if opts.ConnMaxLifetime != 3*time.Minute {
		t.Errorf("Expected ConnMaxLifetime=3m, got %v", opts.ConnMaxLifetime)
	}
	if !opts.EnablePoolMonitoring {
		t.Error("Expected EnablePoolMonitoring=true")
	}
	if opts.PrometheusRegisterer != prometheus.DefaultRegisterer {
		t.Error("Expected PrometheusRegisterer to be DefaultRegisterer")
	}
	if len(opts.ConfigFiles) == 0 {
		t.Error("Expected ConfigFiles to be non-empty")
	}
}

func TestMonitorConfigOptions(t *testing.T) {
	opts := MonitorConfigOptions()

	// Verify expected defaults for Monitor package
	if opts.MaxOpenConns != 10 {
		t.Errorf("Expected MaxOpenConns=10, got %d", opts.MaxOpenConns)
	}
	if opts.MaxIdleConns != 5 {
		t.Errorf("Expected MaxIdleConns=5, got %d", opts.MaxIdleConns)
	}
	if opts.ConnMaxLifetime != 3*time.Minute {
		t.Errorf("Expected ConnMaxLifetime=3m, got %v", opts.ConnMaxLifetime)
	}
	if opts.EnablePoolMonitoring {
		t.Error("Expected EnablePoolMonitoring=false")
	}
	if opts.PrometheusRegisterer != nil {
		t.Error("Expected PrometheusRegisterer to be nil")
	}
	if len(opts.ConfigFiles) == 0 {
		t.Error("Expected ConfigFiles to be non-empty")
	}
}

func TestConfigStructures(t *testing.T) {
	// Test that MySQL configuration structures can be created and populated
	config := Config{
		MySQL: &MySQLConfig{
			DSN:    "user:pass@tcp(localhost:3306)/dbname",
			User:   "testuser",
			Pass:   "testpass",
			DBName: "testdb",
		},
	}

	if config.MySQL.DSN == "" {
		t.Error("Expected DSN to be set")
	}
	if config.MySQL.User != "testuser" {
		t.Errorf("Expected User='testuser', got '%s'", config.MySQL.User)
	}
	if config.MySQL.Pass != "testpass" {
		t.Errorf("Expected Pass='testpass', got '%s'", config.MySQL.Pass)
	}
	if config.MySQL.DBName != "testdb" {
		t.Errorf("Expected DBName='testdb', got '%s'", config.MySQL.DBName)
	}
}

func TestPostgresConfigStructures(t *testing.T) {
	// Test that PostgreSQL configuration structures can be created and populated
	config := Config{
		Postgres: &PostgresConfig{
			Host:    "localhost",
			Port:    5432,
			User:    "testuser",
			Pass:    "testpass",
			Name:    "testdb",
			SSLMode: "require",
		},
	}

	if config.Postgres.Host != "localhost" {
		t.Errorf("Expected Host='localhost', got '%s'", config.Postgres.Host)
	}
	if config.Postgres.Port != 5432 {
		t.Errorf("Expected Port=5432, got %d", config.Postgres.Port)
	}
	if config.Postgres.User != "testuser" {
		t.Errorf("Expected User='testuser', got '%s'", config.Postgres.User)
	}
	if config.Postgres.Pass != "testpass" {
		t.Errorf("Expected Pass='testpass', got '%s'", config.Postgres.Pass)
	}
	if config.Postgres.Name != "testdb" {
		t.Errorf("Expected Name='testdb', got '%s'", config.Postgres.Name)
	}
	if config.Postgres.SSLMode != "require" {
		t.Errorf("Expected SSLMode='require', got '%s'", config.Postgres.SSLMode)
	}
}

func TestLegacyPostgresConfig(t *testing.T) {
	// Test that legacy flat PostgreSQL format can be created
	config := Config{
		User:    "testuser",
		Pass:    "testpass",
		Host:    "localhost",
		Port:    5432,
		Name:    "testdb",
		SSLMode: "require",
	}

	if config.User != "testuser" {
		t.Errorf("Expected User='testuser', got '%s'", config.User)
	}
	if config.Name != "testdb" {
		t.Errorf("Expected Name='testdb', got '%s'", config.Name)
	}
}

func TestConfigValidation(t *testing.T) {
	tests := []struct {
		name    string
		config  Config
		wantErr bool
	}{
		{
			name: "valid mysql config",
			config: Config{
				MySQL: &MySQLConfig{DSN: "test"},
			},
			wantErr: false,
		},
		{
			name: "valid postgres config",
			config: Config{
				Postgres: &PostgresConfig{User: "test", Host: "localhost", Name: "test"},
			},
			wantErr: false,
		},
		{
			name: "valid legacy postgres config",
			config: Config{
				User: "test",
				Host: "localhost",
				Name: "testdb",
			},
			wantErr: false,
		},
		{
			name: "both mysql and postgres set",
			config: Config{
				MySQL:    &MySQLConfig{DSN: "test"},
				Postgres: &PostgresConfig{User: "test"},
			},
			wantErr: true,
		},
		{
			name: "mysql and legacy postgres set",
			config: Config{
				MySQL: &MySQLConfig{DSN: "test"},
				User:  "test",
				Name:  "testdb",
			},
			wantErr: true,
		},
		{
			name:    "no config set",
			config:  Config{},
			wantErr: true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := tt.config.Validate()
			if (err != nil) != tt.wantErr {
				t.Errorf("Validate() error = %v, wantErr %v", err, tt.wantErr)
			}
		})
	}
}