package installer

import (
	"testing"

	"gitgud.io/mike/mpv-manager/pkg/config"
	"gitgud.io/mike/mpv-manager/pkg/constants"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

// The version-probe helpers exec read-only system tools (flatpak, pacman,
// apt-cache, ...). They must tolerate missing binaries and missing packages
// and never fail the test based on what the host happens to have installed.

func TestDetectInstalledMPVApps(t *testing.T) {
	// Loose assertion: detection must not error or panic, whatever the host has.
	// A nil/empty result is valid on hosts with no mpv installed (e.g. CI).
	apps := DetectInstalledMPVApps()
	for _, app := range apps {
		assert.NotEmpty(t, app.AppName)
		assert.NotEmpty(t, app.MethodID)
	}
}

func TestVersionProbesTolerateMissingTools(t *testing.T) {
	const bogusPackage = "mpv-manager-definitely-not-installed-pkg"

	assert.Empty(t, getFlatpakAppVersion("io.mpv.MpvDefintelyMissing"))

	for _, family := range []string{constants.PMFamilyDebian, constants.PMFamilyRHEL, constants.PMFamilyArch, constants.PMFamilySUSE, "unknown-family"} {
		version, path := getPackageAppVersion(family, bogusPackage)
		assert.Empty(t, version)
		assert.Empty(t, path)
	}
}

func TestDetectPackageManagerFamily(t *testing.T) {
	// The result depends on the host distro; it just has to be a known family
	// or empty.
	family := detectPackageManagerFamily()
	if family != "" {
		assert.Contains(t, []string{
			constants.PMFamilyDebian,
			constants.PMFamilyRHEL,
			constants.PMFamilyArch,
			constants.PMFamilySUSE,
		}, family)
	}
}

func TestSyncInstalledApps(t *testing.T) {
	isolateConfig(t)

	detected := []DetectedApp{
		{AppName: "MPV", MethodID: constants.MethodMPVFlatpak, Version: "0.39.0", InstallPath: "flatpak run io.mpv.Mpv", InstallType: "flatpak"},
		// A distinct path using the same method is a distinct installation.
		{AppName: "MPV", MethodID: constants.MethodMPVFlatpak, Version: "0.40.0", InstallPath: "other", InstallType: "flatpak"},
	}

	added, removed := SyncInstalledApps(detected)
	assert.Equal(t, 2, added)
	assert.Equal(t, 0, removed)

	apps := config.GetInstalledApps()
	require.Len(t, apps, 2)
	versionsByPath := map[string]string{}
	for _, app := range apps {
		versionsByPath[app.InstallPath] = app.AppVersion
		assert.False(t, app.Managed, "externally detected apps are unmanaged")
	}
	assert.Equal(t, "0.39.0", versionsByPath["flatpak run io.mpv.Mpv"])
	assert.Equal(t, "0.40.0", versionsByPath["other"])

	// Syncing the same set again changes nothing.
	added, removed = SyncInstalledApps(detected)
	assert.Equal(t, 0, added)
	assert.Equal(t, 0, removed)

	// A newer detected version refreshes only the matching identity in place.
	added, removed = SyncInstalledApps([]DetectedApp{
		{AppName: "MPV", MethodID: constants.MethodMPVFlatpak, Version: "0.40.0", InstallPath: "flatpak run io.mpv.Mpv", InstallType: "flatpak"},
	})
	assert.Equal(t, 0, added)
	assert.Equal(t, 0, removed)
	apps = config.GetInstalledApps()
	require.Len(t, apps, 2)
	for _, app := range apps {
		assert.Equal(t, "0.40.0", app.AppVersion)
	}

	// Missing or failed probes are not proof of uninstallation.
	added, removed = SyncInstalledApps(nil)
	assert.Equal(t, 0, added)
	assert.Equal(t, 0, removed)
	require.Len(t, config.GetInstalledApps(), 2)

	added, removed = SyncInstalledAppObservations([]DetectionObservation{
		{
			State: DetectionUnknown,
			App:   DetectedApp{MethodID: constants.MethodMPVFlatpak},
		},
		{
			State: DetectionNotFound,
			App: DetectedApp{
				MethodID:    constants.MethodMPVFlatpak,
				InstallPath: "flatpak run io.mpv.Mpv",
			},
		},
	})
	assert.Equal(t, 0, added)
	assert.Equal(t, 1, removed)
	apps = config.GetInstalledApps()
	require.Len(t, apps, 1)
	assert.Equal(t, "other", apps[0].InstallPath)
}

func TestSyncInstalledAppObservationsFoundWinsAndPathsCanonicalize(t *testing.T) {
	isolateConfig(t)

	observations := []DetectionObservation{
		{State: DetectionNotFound, App: DetectedApp{MethodID: constants.MethodMPVBinary, InstallPath: `C:\Users\Test\mpv\..\MPV`}},
		{State: DetectionFound, App: DetectedApp{AppName: "MPV", MethodID: constants.MethodMPVBinary, Version: "0.40.0", InstallPath: `c:/users/test/mpv`, InstallType: "binary"}},
	}
	added, removed := SyncInstalledAppObservations(observations)
	assert.Equal(t, 1, added)
	assert.Equal(t, 0, removed)
	require.Len(t, config.GetInstalledApps(), 1)
}

func TestDetectAndSyncApps(t *testing.T) {
	isolateConfig(t)
	// Real detection against the host, synced into the sandboxed config.
	added, removed := DetectAndSyncApps()
	assert.GreaterOrEqual(t, added, 0)
	assert.GreaterOrEqual(t, removed, 0)
}