package config

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

func TestLoadMissingFileReturnsDefaults(t *testing.T) {
	s, err := Load(filepath.Join(t.TempDir(), "config.json"))
	if err != nil {
		t.Fatalf("a missing config must not be an error: %v", err)
	}
	if s != Default() {
		t.Errorf("expected defaults, got %+v", s)
	}
	if s.UpdateRepo != DefaultUpdateRepo {
		t.Errorf("update repo default = %q, want %q", s.UpdateRepo, DefaultUpdateRepo)
	}
}

// An absent field takes the default, but an explicitly empty one must stay
// empty — that is how the update check is turned off.
func TestExplicitEmptyUpdateRepoDisablesTheCheck(t *testing.T) {
	path := filepath.Join(t.TempDir(), "config.json")
	if err := os.WriteFile(path, []byte(`{"update_repo": ""}`), 0o644); err != nil {
		t.Fatal(err)
	}

	s, err := Load(path)
	if err != nil {
		t.Fatal(err)
	}
	if s.UpdateRepo != "" {
		t.Errorf("an explicit empty update_repo must be preserved, got %q", s.UpdateRepo)
	}
	// The rest of the file was absent, so it should still be defaulted.
	if s.ActivePollSeconds != Default().ActivePollSeconds {
		t.Errorf("unset fields should keep their defaults, got %+v", s)
	}
}

func TestLoadRepairsNonsense(t *testing.T) {
	path := filepath.Join(t.TempDir(), "config.json")
	if err := os.WriteFile(path, []byte(`{"mask_style":"wat","active_poll_seconds":0}`), 0o644); err != nil {
		t.Fatal(err)
	}

	s, err := Load(path)
	if err != nil {
		t.Fatal(err)
	}
	if s.MaskStyle != MaskPrefix {
		t.Errorf("an unknown mask style should fall back to prefix, got %q", s.MaskStyle)
	}
	if s.ActivePollSeconds != 30 {
		t.Errorf("a zero poll interval should be repaired, got %d", s.ActivePollSeconds)
	}
}

// A corrupt config must not stop the app from starting.
func TestLoadCorruptFileReturnsDefaultsAndError(t *testing.T) {
	path := filepath.Join(t.TempDir(), "config.json")
	if err := os.WriteFile(path, []byte(`{not json`), 0o644); err != nil {
		t.Fatal(err)
	}

	s, err := Load(path)
	if err == nil {
		t.Error("expected an error for a corrupt config")
	}
	if s != Default() {
		t.Errorf("a corrupt config should still yield usable defaults, got %+v", s)
	}
}

func TestSaveRoundTrip(t *testing.T) {
	path := filepath.Join(t.TempDir(), "nested", "config.json")

	want := Default()
	want.MaskStyle = MaskDotted
	want.StartWithWindows = true
	want.UpdateRepo = "https://example.com/o/r"
	if err := want.Save(path); err != nil {
		t.Fatal(err)
	}

	got, err := Load(path)
	if err != nil {
		t.Fatal(err)
	}
	if got != want {
		t.Errorf("round trip changed the settings:\n got %+v\nwant %+v", got, want)
	}
	if !got.DottedMasks() {
		t.Error("DottedMasks should be true for MaskDotted")
	}
}