package config

import (
	"encoding/base64"
	"os"
	"path/filepath"
	"runtime"
	"testing"
)

// TestLoadSanitizesInvalidUTF8 ensures a mangled config file (valid base64 +
// XOR but with invalid UTF-8 inside a string field) loads with replacement
// characters instead of propagating raw bytes into the UI/login request.
func TestLoadSanitizesInvalidUTF8(t *testing.T) {
	if runtime.GOOS != "linux" && runtime.GOOS != "freebsd" {
		t.Skip("XDG_CONFIG_HOME only honored on unix")
	}
	dir := t.TempDir()
	t.Setenv("XDG_CONFIG_HOME", dir)

	// "wine" is a key from pre-Wine-removal configs; unknown fields must be ignored.
	raw := []byte(`{"game_path":"","wine":"wine","user":"u","pass":"abc` + "\xff\xfe" + `de"}`)
	for i := range raw {
		raw[i] ^= key[i%len(key)]
	}
	p := filepath.Join(dir, "ffxiv-tiny-launcher", "config")
	if err := os.MkdirAll(filepath.Dir(p), 0o700); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(p, []byte(base64.StdEncoding.EncodeToString(raw)), 0o600); err != nil {
		t.Fatal(err)
	}

	cfg, err := Load()
	if err != nil {
		t.Fatal(err)
	}
	// ToValidUTF8 replaces a whole run of invalid bytes with one rune.
	want := "abc\ufffdde"
	if cfg.Pass != want {
		t.Fatalf("pass = %q, want %q", cfg.Pass, want)
	}
	if cfg.User != "u" {
		t.Fatalf("user = %q, want %q", cfg.User, "u")
	}
}

func TestSaveAtomicAndRoundTrip(t *testing.T) {
	dir := t.TempDir()
	if runtime.GOOS == "linux" || runtime.GOOS == "freebsd" {
		t.Setenv("XDG_CONFIG_HOME", dir)
	} else if runtime.GOOS == "windows" {
		t.Setenv("APPDATA", dir)
	}

	in := Config{GamePath: `C:\ffxiv`, User: "u", Pass: "p"}
	if err := Save(in); err != nil {
		t.Fatal(err)
	}
	out, err := Load()
	if err != nil {
		t.Fatal(err)
	}
	if out != in {
		t.Fatalf("round trip = %+v, want %+v", out, in)
	}
	p, _ := Path()
	if _, err := os.Stat(p + ".tmp"); !os.IsNotExist(err) {
		t.Fatalf("leftover temp file %q (err=%v)", p+".tmp", err)
	}
}