package domain

import (
	"errors"
	"testing"
)

func TestAppStatusValid(t *testing.T) {
	statuses := []AppStatus{
		StatusNotInstalled,
		StatusQueued,
		StatusDownloading,
		StatusVerifying,
		StatusExtracting,
		StatusInstalling,
		StatusInstalled,
		StatusUpdateAvailable,
		StatusRunning,
		StatusFailed,
		StatusRollbackPending,
		StatusIncompatible,
	}

	for _, status := range statuses {
		if !status.Valid() {
			t.Errorf("status %q should be valid", status)
		}
	}

	if AppStatus("unknown").Valid() {
		t.Fatal("unknown status should be invalid")
	}
}

func TestValidateTransition(t *testing.T) {
	tests := []struct {
		name string
		from AppStatus
		to   AppStatus
		want error
	}{
		{name: "queue install", from: StatusNotInstalled, to: StatusQueued},
		{name: "start download", from: StatusQueued, to: StatusDownloading},
		{name: "pause download", from: StatusDownloading, to: StatusQueued},
		{name: "finish install", from: StatusInstalling, to: StatusInstalled},
		{name: "start app", from: StatusInstalled, to: StatusRunning},
		{name: "recover rollback", from: StatusRollbackPending, to: StatusInstalled},
		{name: "skip install pipeline", from: StatusNotInstalled, to: StatusInstalled, want: ErrInvalidTransition},
		{name: "download while running", from: StatusRunning, to: StatusDownloading, want: ErrInvalidTransition},
		{name: "extract incompatible app", from: StatusIncompatible, to: StatusExtracting, want: ErrInvalidTransition},
		{name: "same status", from: StatusInstalled, to: StatusInstalled, want: ErrInvalidTransition},
		{name: "unknown source", from: AppStatus("unknown"), to: StatusQueued, want: ErrInvalidStatus},
		{name: "unknown target", from: StatusQueued, to: AppStatus("unknown"), want: ErrInvalidStatus},
	}

	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			err := ValidateTransition(test.from, test.to)
			if test.want == nil {
				if err != nil {
					t.Fatalf("ValidateTransition(%q, %q) error = %v", test.from, test.to, err)
				}
				if !CanTransition(test.from, test.to) {
					t.Fatalf("CanTransition(%q, %q) = false, want true", test.from, test.to)
				}
				return
			}

			if !errors.Is(err, test.want) {
				t.Fatalf("ValidateTransition(%q, %q) error = %v, want %v", test.from, test.to, err, test.want)
			}
			if CanTransition(test.from, test.to) {
				t.Fatalf("CanTransition(%q, %q) = true, want false", test.from, test.to)
			}
		})
	}
}