// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
// SPDX-License-Identifier: GPL-3.0-or-later

package atspi

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

func TestFlatpakProcessInstanceBoundaries(t *testing.T) {
	root := t.TempDir()
	write := func(pid int, data string) {
		t.Helper()
		dir := filepath.Join(root, fmt.Sprint(pid), "root")
		if err := os.MkdirAll(dir, 0700); err != nil {
			t.Fatal(err)
		}
		if err := os.WriteFile(filepath.Join(dir, ".flatpak-info"), []byte(data), 0600); err != nil {
			t.Fatal(err)
		}
	}
	metadata := "[Application]\nname=org.example.App\n[Instance]\ninstance-id=123\n"
	write(100, metadata)
	for _, test := range []struct {
		name, data string
		want       bool
	}{
		{"same instance", metadata, true},
		{"other instance of same app", strings.ReplaceAll(metadata, "123", "456"), false},
		{"other app", strings.ReplaceAll(metadata, "org.example.App", "org.example.Other"), false},
		{"app ID alone", "[Application]\nname=org.example.App\n", false},
		{"instance ID alone", "[Instance]\ninstance-id=123\n", false},
		{"wrong section", "[Application]\nname=org.example.App\ninstance-id=123\n", false},
		{"empty metadata", "", false},
		{"malformed metadata", metadata + "broken", false},
		{"duplicate identity", metadata + "instance-id=456\n", false},
		{"oversized metadata", metadata + strings.Repeat("#", 65536), false},
	} {
		t.Run(test.name, func(t *testing.T) {
			write(200, test.data)
			if got := sameFlatpakInstance(root, 100, 200); got != test.want {
				t.Fatalf("same instance = %v; want %v", got, test.want)
			}
		})
	}
	if sameFlatpakInstance(root, 100, 300) || sameFlatpakInstance(root, 300, 400) || sameFlatpakInstance(root, 0, 0) {
		t.Fatal("missing process or unknown identity matched")
	}
}