package config

import (
	"log/slog"
	"strings"
	"testing"
	"time"
)

func TestLoadRequiresDSN(t *testing.T) {
	t.Setenv("HAMMY_DSN", "")

	if _, err := Load(); err == nil {
		t.Fatal("expected an error when HAMMY_DSN is unset")
	}
}

func TestLoadDefaults(t *testing.T) {
	t.Setenv("HAMMY_DSN", "postgres://u:p@localhost/hammy")

	c, err := Load()
	if err != nil {
		t.Fatal(err)
	}

	if c.Addr != "127.0.0.1:8080" {
		t.Errorf("Addr %q, want localhost by default - binding 0.0.0.0 should be deliberate", c.Addr)
	}
	if c.MaxConns != 10 {
		t.Errorf("MaxConns %d, want 10", c.MaxConns)
	}
	if c.LogLevel != slog.LevelInfo {
		t.Errorf("LogLevel %v, want info", c.LogLevel)
	}
	if c.RedisAddr != "" {
		t.Errorf("RedisAddr %q, want empty", c.RedisAddr)
	}
}

func TestLoadOverrides(t *testing.T) {
	t.Setenv("HAMMY_DSN", "postgres://u:p@localhost/hammy")
	t.Setenv("HAMMY_ADDR", ":9000")
	t.Setenv("HAMMY_MAX_CONNS", "25")
	t.Setenv("HAMMY_LOG_LEVEL", "debug")
	t.Setenv("HAMMY_SHUTDOWN_TIMEOUT", "45s")
	t.Setenv("HAMMY_REDIS_ADDR", "localhost:6379")

	c, err := Load()
	if err != nil {
		t.Fatal(err)
	}

	if c.Addr != ":9000" || c.MaxConns != 25 || c.LogLevel != slog.LevelDebug {
		t.Errorf("overrides not applied: %+v", c)
	}
	if c.ShutdownTimeout != 45*time.Second {
		t.Errorf("ShutdownTimeout %v, want 45s", c.ShutdownTimeout)
	}
}

func TestLoadRejectsBadValues(t *testing.T) {
	t.Setenv("HAMMY_DSN", "postgres://u:p@localhost/hammy")

	for _, c := range []struct{ key, val string }{
		{"HAMMY_MAX_CONNS", "lots"},
		{"HAMMY_LOG_LEVEL", "verbose"},
		{"HAMMY_SHUTDOWN_TIMEOUT", "soon"},
	} {
		t.Run(c.key, func(t *testing.T) {
			t.Setenv(c.key, c.val)

			if _, err := Load(); err == nil {
				t.Errorf("%s=%q accepted", c.key, c.val)
			}
		})
	}
}

// A DSN in a startup log is a password in a log.
func TestRedactedHidesPassword(t *testing.T) {
	cases := []string{
		"postgres://hammy_app:hunter2@192.168.1.127:5432/hammy",
		"postgresql://hammy_app:p%40ss@localhost/hammy?sslmode=verify-full",
	}

	for _, dsn := range cases {
		c := Config{DSN: dsn, Addr: ":8080", MaxConns: 10}
		out := c.Redacted()

		if strings.Contains(out, "hunter2") || strings.Contains(out, "p%40ss") {
			t.Errorf("password leaked: %s", out)
		}
		if !strings.Contains(out, "hammy_app") {
			t.Errorf("username should survive for diagnosis: %s", out)
		}
	}

	// A DSN with no credentials must not panic or produce nonsense.
	c := Config{DSN: "postgres:///hammy?host=/var/run/postgresql"}
	if out := c.Redacted(); strings.Contains(out, "***") && !strings.Contains(out, "(set)") {
		t.Logf("socket DSN rendered as: %s", out)
	}
}