package platform

import (
	"context"
	"path/filepath"
	"runtime"
	"testing"
)

func TestDetect_MatchesRuntime(t *testing.T) {
	t.Parallel()

	info := Detect()
	if info.GOOS != runtime.GOOS {
		t.Errorf("Detect().GOOS = %q, want %q", info.GOOS, runtime.GOOS)
	}
	if info.GOARCH != runtime.GOARCH {
		t.Errorf("Detect().GOARCH = %q, want %q", info.GOARCH, runtime.GOARCH)
	}
	if info.CPUs <= 0 {
		t.Errorf("Detect().CPUs = %d, want > 0", info.CPUs)
	}
	if info.Name == "" {
		t.Error("Detect().Name is empty")
	}
}

func TestOSPredicates_ConsistentWithRuntime(t *testing.T) {
	t.Parallel()

	wantWindows := runtime.GOOS == "windows"
	wantDarwin := runtime.GOOS == "darwin"
	wantLinux := runtime.GOOS == "linux"

	if IsWindows() != wantWindows {
		t.Errorf("IsWindows() = %v, want %v", IsWindows(), wantWindows)
	}
	if IsDarwin() != wantDarwin {
		t.Errorf("IsDarwin() = %v, want %v", IsDarwin(), wantDarwin)
	}
	if IsLinux() != wantLinux {
		t.Errorf("IsLinux() = %v, want %v", IsLinux(), wantLinux)
	}
	if IsUnix() != (runtime.GOOS != "windows") {
		t.Errorf("IsUnix() = %v, want %v", IsUnix(), runtime.GOOS != "windows")
	}
}

func TestArchLabel_Mapping(t *testing.T) {
	t.Parallel()

	tests := []struct {
		goarch string
		want   string
	}{
		{goarch: "amd64", want: "x86_64"},
		{goarch: "arm64", want: "arm64"},
		{goarch: "386", want: "x86"},
		{goarch: "riscv64", want: "riscv64"},
	}
	for _, tt := range tests {
		tt := tt
		t.Run(tt.goarch, func(t *testing.T) {
			t.Parallel()
			if got := archLabel(tt.goarch); got != tt.want {
				t.Fatalf("archLabel(%q) = %q, want %q", tt.goarch, got, tt.want)
			}
		})
	}
}

func TestDefaultDataDir_XDGOnLinux(t *testing.T) {
	if runtime.GOOS != "linux" {
		t.Skip("XDG_DATA_HOME only applies on linux")
	}

	t.Setenv("XDG_DATA_HOME", "/tmp/cyrene-xdg")
	got := DefaultDataDir()
	want := filepath.Join("/tmp/cyrene-xdg", "cyrene")
	if got != want {
		t.Errorf("DefaultDataDir() = %q, want %q", got, want)
	}
}

func TestSignalContext_Cancelable(t *testing.T) {
	t.Parallel()

	ctx, cancel := SignalContext()
	if ctx == nil {
		t.Fatal("SignalContext() returned nil context")
	}
	if cancel == nil {
		t.Fatal("SignalContext() returned nil cancel func")
	}
	cancel()
	if ctx.Err() != context.Canceled {
		t.Errorf("ctx.Err() = %v, want context.Canceled", ctx.Err())
	}
}