package pgdb

import (
	"context"
	"os"
	"strings"
	"testing"
	"time"

	"go.ntppool.org/common/database"
)

func TestCreatePoolConfig(t *testing.T) {
	tests := []struct {
		name    string
		cfg     *database.PostgresConfig
		wantErr bool
	}{
		{
			name: "valid config",
			cfg: &database.PostgresConfig{
				Host:    "localhost",
				Port:    5432,
				User:    "testuser",
				Pass:    "testpass",
				Name:    "testdb",
				SSLMode: "require",
			},
			wantErr: false,
		},
		{
			name: "valid config with defaults",
			cfg: &database.PostgresConfig{
				Host: "localhost",
				User: "testuser",
				Pass: "testpass",
				Name: "testdb",
				// Port and SSLMode will use defaults
			},
			wantErr: false,
		},
		{
			name: "missing host",
			cfg: &database.PostgresConfig{
				User: "testuser",
				Pass: "testpass",
				Name: "testdb",
			},
			wantErr: true,
		},
		{
			name: "missing user",
			cfg: &database.PostgresConfig{
				Host: "localhost",
				Pass: "testpass",
				Name: "testdb",
			},
			wantErr: true,
		},
		{
			name: "missing database name",
			cfg: &database.PostgresConfig{
				Host: "localhost",
				User: "testuser",
				Pass: "testpass",
			},
			wantErr: true,
		},
		{
			name: "invalid sslmode",
			cfg: &database.PostgresConfig{
				Host:    "localhost",
				User:    "testuser",
				Pass:    "testpass",
				Name:    "testdb",
				SSLMode: "invalid",
			},
			wantErr: true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			poolCfg, err := CreatePoolConfig(tt.cfg)
			if (err != nil) != tt.wantErr {
				t.Errorf("CreatePoolConfig() error = %v, wantErr %v", err, tt.wantErr)
				return
			}
			if !tt.wantErr && poolCfg == nil {
				t.Error("CreatePoolConfig() returned nil config without error")
			}
			if !tt.wantErr && poolCfg != nil {
				// Verify config fields are set correctly
				if poolCfg.ConnConfig.Host != tt.cfg.Host && tt.cfg.Host != "" {
					t.Errorf("Expected Host=%s, got %s", tt.cfg.Host, poolCfg.ConnConfig.Host)
				}
				if poolCfg.ConnConfig.User != tt.cfg.User {
					t.Errorf("Expected User=%s, got %s", tt.cfg.User, poolCfg.ConnConfig.User)
				}
				if poolCfg.ConnConfig.Password != tt.cfg.Pass {
					t.Errorf("Expected Password to be set correctly")
				}
				if poolCfg.ConnConfig.Database != tt.cfg.Name {
					t.Errorf("Expected Database=%s, got %s", tt.cfg.Name, poolCfg.ConnConfig.Database)
				}
			}
		})
	}
}

func TestDefaultPoolOptions(t *testing.T) {
	opts := DefaultPoolOptions()

	// Verify expected defaults
	if opts.MinConns != 0 {
		t.Errorf("Expected MinConns=0, got %d", opts.MinConns)
	}
	if opts.MaxConns != 4 {
		t.Errorf("Expected MaxConns=4 (pgxpool default), got %d", opts.MaxConns)
	}
	if opts.MaxConnLifetime != time.Hour {
		t.Errorf("Expected MaxConnLifetime=1h, got %v", opts.MaxConnLifetime)
	}
	if opts.MaxConnIdleTime != 30*time.Minute {
		t.Errorf("Expected MaxConnIdleTime=30m, got %v", opts.MaxConnIdleTime)
	}
	if opts.HealthCheckPeriod != time.Minute {
		t.Errorf("Expected HealthCheckPeriod=1m, got %v", opts.HealthCheckPeriod)
	}
	if len(opts.ConfigFiles) == 0 {
		t.Error("Expected ConfigFiles to be non-empty")
	}
}

func TestCreatePoolConfigDefaults(t *testing.T) {
	// Test that defaults are applied correctly
	cfg := &database.PostgresConfig{
		Host: "localhost",
		User: "testuser",
		Pass: "testpass",
		Name: "testdb",
		// Port and SSLMode not set
	}

	poolCfg, err := CreatePoolConfig(cfg)
	if err != nil {
		t.Fatalf("CreatePoolConfig() failed: %v", err)
	}

	// Verify defaults were applied
	if poolCfg.ConnConfig.Port != 5432 {
		t.Errorf("Expected default Port=5432, got %d", poolCfg.ConnConfig.Port)
	}
}

func TestOpenPoolWithDatabaseURI(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping integration test")
	}

	// This test requires a running PostgreSQL instance
	uri := os.Getenv("TEST_DATABASE_URI")
	if uri == "" {
		t.Skip("TEST_DATABASE_URI not set")
	}

	ctx := context.Background()
	t.Setenv("DATABASE_URI", uri)

	pool, err := OpenPool(ctx, DefaultPoolOptions())
	if err != nil {
		t.Fatalf("OpenPool failed: %v", err)
	}
	defer pool.Close()

	// Verify connection works
	var result int
	err = pool.QueryRow(ctx, "SELECT 1").Scan(&result)
	if err != nil {
		t.Fatalf("query failed: %v", err)
	}
	if result != 1 {
		t.Errorf("expected 1, got %d", result)
	}
}

func TestDatabaseURIPrecedence(t *testing.T) {
	// Test that DATABASE_URI takes precedence over config files
	// We use localhost with a port that's unlikely to have postgres running
	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
	defer cancel()

	// Set DATABASE_URI to a parseable URI pointing to a non-listening port
	t.Setenv("DATABASE_URI", "postgres://testuser:testpass@127.0.0.1:59999/testdb?connect_timeout=1")

	// Set config files to a nonexistent path - if this were used, we'd get
	// "config file not found" error instead of connection refused
	opts := DefaultPoolOptions()
	opts.ConfigFiles = []string{"/nonexistent/path/database.yaml"}

	_, err := OpenPool(ctx, opts)

	// Should fail with connection error (not config file error)
	// This proves DATABASE_URI was used instead of config files
	if err == nil {
		t.Fatal("expected error, got nil")
	}

	// The error should be about connection failure, not about missing config file
	errStr := err.Error()
	if strings.Contains(errStr, "config file") || strings.Contains(errStr, "no such file") {
		t.Errorf("expected connection error, got config file error: %v", err)
	}
}