package main

import (
	"errors"
	"fmt"
	"io"
	"os"
	"path/filepath"
	"reflect"
	"strings"
	"sync"
	"testing"
	"time"

	"coopcloud.tech/abra/pkg/config"
	"coopcloud.tech/abra/pkg/recipe"
	"coopcloud.tech/abra/pkg/upstream/convert"
	"coopcloud.tech/abra/pkg/upstream/stack"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/docker/docker/api/types/swarm"
	"github.com/evertras/bubble-table/table"
)

// testApp builds an app pinned to an explicit stack name so that tests do not
// depend on abra's stack name sanitisation rules.
func testApp(domain, server, recipeName, stackName string) config.App {
	return config.App{
		Name:   domain,
		Domain: domain,
		Server: server,
		Recipe: recipeName,
		Env:    config.AppEnv{"STACK_NAME": stackName},
	}
}

// labelledService builds a swarm service carrying the Co-op Cloud labels for a
// stack, using the same label keys as the production code.
func labelledService(stackName string, values map[string]string) swarm.Service {
	labels := map[string]string{convert.LabelNamespace: stackName}
	for suffix, value := range values {
		labels[labelKey(stackName, suffix)] = value
	}

	return swarm.Service{
		Spec: swarm.ServiceSpec{Annotations: swarm.Annotations{Labels: labels}},
	}
}

// testModel builds a model backed by a table of the given apps.
func testModel(apps []config.App) model {
	return model{
		apps:  apps,
		table: newTable(newRows(apps), 200, 40),
	}
}

// keyMsg builds a rune key message.
func keyMsg(r rune) tea.KeyMsg {
	return tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune{r}}
}

// send delivers a key to the model and returns the updated model.
func send(t *testing.T, m model, r rune) (model, tea.Cmd) {
	t.Helper()

	updated, cmd := m.Update(keyMsg(r))

	next, ok := updated.(model)
	if !ok {
		t.Fatalf("Update returned a %T, want a model", updated)
	}

	return next, cmd
}

// containsQuit reports whether cmd is, or batches, bubbletea's quit command.
// The quit message type is unexported, so the commands are compared by code
// pointer. Only batch closures are invoked, which never run their children.
func containsQuit(cmd tea.Cmd) bool {
	if cmd == nil {
		return false
	}

	if reflect.ValueOf(cmd).Pointer() == reflect.ValueOf(tea.Quit).Pointer() {
		return true
	}

	batch, ok := cmd().(tea.BatchMsg)
	if !ok {
		return false
	}

	for _, child := range batch {
		if containsQuit(child) {
			return true
		}
	}

	return false
}

// rowFor returns the first visible row of a table.
func rowFor(t *testing.T, tbl table.Model) table.Row {
	t.Helper()

	rows := tbl.GetVisibleRows()
	if len(rows) != 1 {
		t.Fatalf("expected exactly one visible row, got %v", len(rows))
	}

	return rows[0]
}

// B3: most stacks run more than one service, and the last service read must not
// wipe out the status of the stack.
func TestParseServiceStatusesMultiServiceStack(t *testing.T) {
	const name = "myapp_com_example"

	statuses := parseServiceStatuses([]stack.StackStatus{{
		Services: []swarm.Service{
			labelledService(name, map[string]string{
				"version": "1.0.0",
				"chaos":   "true",
			}),
			// A second service in the same stack, as any app with a database
			// has, must not drop the keys the first service set.
			labelledService(name, map[string]string{
				"version": "1.0.0",
			}),
		},
	}})

	status, ok := statuses[name]
	if !ok {
		t.Fatalf("expected a status for stack %q, got %v", name, statuses)
	}

	if got := status[keyStatus]; got != "deployed" {
		t.Errorf("status = %q, want %q", got, "deployed")
	}

	if got := status[keyVersion]; got != "1.0.0" {
		t.Errorf("version = %q, want %q", got, "1.0.0")
	}

	if got := status[keyChaos]; got != "true" {
		t.Errorf("chaos = %q, want %q", got, "true")
	}
}

// B4: a deployed stack with no version label is still deployed.
func TestParseServiceStatusesMissingVersionLabel(t *testing.T) {
	const name = "myapp_com_example"

	statuses := parseServiceStatuses([]stack.StackStatus{{
		Services: []swarm.Service{
			labelledService(name, map[string]string{"autoupdate": "true"}),
		},
	}})

	status, ok := statuses[name]
	if !ok {
		t.Fatalf("expected a status for stack %q, got %v", name, statuses)
	}

	if got := status[keyStatus]; got != "deployed" {
		t.Errorf("status = %q, want %q", got, "deployed")
	}

	if got, ok := status[keyVersion]; ok {
		t.Errorf("version = %q, want it to be absent", got)
	}

	if got := status[keyAutoUpdate]; got != "true" {
		t.Errorf("auto-update = %q, want %q", got, "true")
	}
}

func TestParseServiceStatusesDefaults(t *testing.T) {
	const name = "myapp_com_example"

	statuses := parseServiceStatuses([]stack.StackStatus{
		{Err: errors.New("ssh: unreachable")},
		{Services: []swarm.Service{
			{Spec: swarm.ServiceSpec{Annotations: swarm.Annotations{
				Labels: map[string]string{},
			}}},
			labelledService(name, map[string]string{"version": "1.0.0"}),
		}},
	})

	status, ok := statuses[name]
	if !ok {
		t.Fatalf("expected a status for stack %q", name)
	}

	if got := status[keyAutoUpdate]; got != "false" {
		t.Errorf("auto-update = %q, want %q", got, "false")
	}
}

// B2: the auto-update column is keyed "auto-update" and must be rendered.
func TestRenderAppsDeployStatusAutoUpdate(t *testing.T) {
	const name = "myapp_com_example"

	m := testModel([]config.App{testApp("example.com", "srv", "myrecipe", name)})

	rendered := renderAppsDeployStatus(&m, appsDeployStatusMsg{
		statuses: map[string]map[string]string{
			name: {
				keyStatus:     "deployed",
				keyVersion:    "1.0.0",
				keyUpdates:    "✅",
				keyAutoUpdate: "true",
			},
		},
	})

	row := rowFor(t, rendered)

	if got := row.Data[keyAutoUpdate]; got != "true" {
		t.Errorf("auto-update = %q, want %q", got, "true")
	}

	if got := row.Data[keyVersion]; got != "1.0.0" {
		t.Errorf("version = %q, want %q", got, "1.0.0")
	}
}

func TestRenderAppsDeployStatusUnknown(t *testing.T) {
	const name = "myapp_com_example"

	m := testModel([]config.App{testApp("example.com", "srv", "myrecipe", name)})

	rendered := renderAppsDeployStatus(&m, appsDeployStatusMsg{
		statuses: map[string]map[string]string{},
	})

	row := rowFor(t, rendered)

	for _, key := range statusKeys {
		if got := row.Data[key]; got != unknownStatus {
			t.Errorf("%s = %q, want %q", key, got, unknownStatus)
		}
	}
}

// B7: an unparseable catalogue tag must not be masked by a later ✅.
func TestResolveUpdates(t *testing.T) {
	tests := []struct {
		name     string
		deployed string
		versions []string
		want     string
	}{
		{name: "up to date", deployed: "1.1.0", versions: []string{"1.0.0", "1.1.0"}, want: "✅"},
		{name: "no catalogue entry", deployed: "1.0.0", versions: nil, want: "✅"},
		{name: "one update", deployed: "1.0.0", versions: []string{"1.0.0", "1.1.0"}, want: "1"},
		{name: "several updates", deployed: "1.0.0", versions: []string{"1.1.0", "1.2.0", "2.0.0"}, want: "3"},
		{name: "newer is excluded", deployed: "2.0.0", versions: []string{"1.0.0"}, want: "✅"},
		{name: "unparseable catalogue tag", deployed: "1.0.0", versions: []string{"latest"}, want: unknownStatus},
		{name: "unparseable deployed tag", deployed: "nightly", versions: []string{"1.0.0"}, want: unknownStatus},
	}

	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			const name = "myapp_com_example"

			var versions recipe.RecipeVersions
			for _, version := range test.versions {
				versions = append(versions, map[string]map[string]recipe.ServiceMeta{
					version: {"app": recipe.ServiceMeta{Image: "img", Tag: version}},
				})
			}

			catl := recipe.RecipeCatalogue{
				"myrecipe": recipe.RecipeMeta{Versions: versions},
			}

			statuses := map[string]map[string]string{
				name: {keyStatus: "deployed", keyVersion: test.deployed},
			}

			resolveUpdates([]config.App{testApp("example.com", "srv", "myrecipe", name)}, statuses, catl)

			if got := statuses[name][keyUpdates]; got != test.want {
				t.Errorf("updates = %q, want %q", got, test.want)
			}
		})
	}
}

func TestResolveUpdatesSkipsUnknownApps(t *testing.T) {
	const name = "myapp_com_example"

	statuses := map[string]map[string]string{
		name: {keyStatus: "deployed", keyVersion: "1.0.0"},
	}

	apps := []config.App{
		testApp("example.com", "srv", "myrecipe", name),
		// Not deployed at all, so it must be left alone.
		testApp("other.com", "srv", "myrecipe", "other_com_other"),
	}

	resolveUpdates(apps, statuses, recipe.RecipeCatalogue{})

	if got := statuses[name][keyUpdates]; got != "✅" {
		t.Errorf("updates = %q, want %q", got, "✅")
	}

	if _, ok := statuses["other_com_other"]; ok {
		t.Error("expected no status for an app which is not deployed")
	}
}

// B1: pressing q while the fuzzy filter has focus must type a q, not quit.
func TestUpdateFilterInputDoesNotQuit(t *testing.T) {
	m := testModel([]config.App{testApp("example.com", "srv", "myrecipe", "myapp_com_example")})

	m, _ = send(t, m, '/')

	if !m.table.GetIsFilterInputFocused() {
		t.Fatal("expected the filter input to have focus after pressing /")
	}

	m, cmd := send(t, m, 'q')

	if containsQuit(cmd) {
		t.Error("pressing q inside the filter quit cctuip")
	}

	if got := m.table.GetCurrentFilter(); got != "q" {
		t.Errorf("filter = %q, want %q", got, "q")
	}
}

func TestUpdateQuitsOutsideFilter(t *testing.T) {
	m := testModel([]config.App{testApp("example.com", "srv", "myrecipe", "myapp_com_example")})

	_, cmd := send(t, m, 'q')

	if !containsQuit(cmd) {
		t.Error("expected pressing q to quit when the filter is not focused")
	}
}

// B5: bubble-table renders nothing at all on a non-positive page size.
func TestPageSizeClamped(t *testing.T) {
	tests := []struct {
		height int
		want   int
	}{
		{height: 40, want: 30},
		{height: 11, want: 1},
		{height: 10, want: 1},
		{height: 4, want: 1},
		{height: 0, want: 1},
		{height: -5, want: 1},
	}

	for _, test := range tests {
		if got := pageSize(test.height); got != test.want {
			t.Errorf("pageSize(%v) = %v, want %v", test.height, got, test.want)
		}

		tbl := newTable(newRows([]config.App{testApp("a.com", "srv", "r", "s")}), 80, test.height)
		if got := tbl.PageSize(); got < 1 {
			t.Errorf("newTable(%v rows tall) gave page size %v, want at least 1", test.height, got)
		}

		// A non-positive page size makes bubble-table render no rows at all,
		// so assert the row really does reach the screen.
		if view := tbl.View(); !strings.Contains(view, "a.com") {
			t.Errorf("newTable(%v rows tall) rendered no row:\n%v", test.height, view)
		}
	}
}

func TestFetchAllRespectsConcurrencyLimit(t *testing.T) {
	var (
		mu      sync.Mutex
		running int
		peak    int
	)

	fetcher := func(string) stack.StackStatus {
		mu.Lock()
		running++
		if running > peak {
			peak = running
		}
		mu.Unlock()

		time.Sleep(2 * time.Millisecond)

		mu.Lock()
		running--
		mu.Unlock()

		return stack.StackStatus{}
	}

	var servers []string
	for i := 0; i < 20; i++ {
		servers = append(servers, fmt.Sprintf("srv-%v", i))
	}

	fetchAll(fetcher, servers, 3)

	if peak > 3 {
		t.Errorf("ran %v servers at once, want at most 3", peak)
	}

	if peak == 0 {
		t.Error("expected the fetcher to be called")
	}
}

func TestFetchAllCollectsServerErrors(t *testing.T) {
	fetcher := func(server string) stack.StackStatus {
		if server != "ok" {
			return stack.StackStatus{Err: fmt.Errorf("ssh: cannot reach %s", server)}
		}

		return stack.StackStatus{Services: []swarm.Service{
			labelledService("myapp_com_example", map[string]string{"version": "1.0.0"}),
		}}
	}

	all, serverErrors := fetchAll(fetcher, []string{"ok", "broken-1", "broken-2"}, 2)

	if len(serverErrors) != 2 {
		t.Errorf("got %v server errors, want 2: %v", len(serverErrors), serverErrors)
	}

	for _, server := range []string{"broken-1", "broken-2"} {
		if _, ok := serverErrors[server]; !ok {
			t.Errorf("expected an error for server %q", server)
		}
	}

	if len(all) != 1 {
		t.Fatalf("got %v results, want 1: a healthy server must still be returned", len(all))
	}

	// The healthy server's statuses survive alongside the errors.
	if got := parseServiceStatuses(all)["myapp_com_example"][keyVersion]; got != "1.0.0" {
		t.Errorf("version = %q, want %q", got, "1.0.0")
	}
}

func TestFetchAllEmpty(t *testing.T) {
	called := false
	fetcher := func(string) stack.StackStatus {
		called = true
		return stack.StackStatus{}
	}

	all, serverErrors := fetchAll(fetcher, nil, 0)

	if called {
		t.Error("expected no servers to be queried")
	}

	if len(all) != 0 || len(serverErrors) != 0 {
		t.Errorf("got %v results and %v errors, want none", len(all), len(serverErrors))
	}
}

func TestSummariseProblems(t *testing.T) {
	if err := summariseProblems(appsDeployStatusMsg{}); err != nil {
		t.Errorf("expected no error when nothing went wrong, got %v", err)
	}

	tests := []struct {
		name string
		msg  appsDeployStatusMsg
		want string
	}{
		{
			name: "single server",
			msg: appsDeployStatusMsg{
				serverErrors: map[string]error{"a": errors.New("boom")},
			},
			want: "a: boom",
		},
		{
			name: "sorted",
			msg: appsDeployStatusMsg{
				serverErrors: map[string]error{
					"b": errors.New("boom"),
					"a": errors.New("boom"),
				},
			},
			want: "a: boom, b: boom",
		},
		{
			name: "truncated",
			msg: appsDeployStatusMsg{
				serverErrors: map[string]error{
					"a": errors.New("boom"),
					"b": errors.New("boom"),
					"c": errors.New("boom"),
					"d": errors.New("boom"),
				},
			},
			want: "a: boom, b: boom, c: boom, …and 1 more",
		},
		{
			name: "catalogue",
			msg:  appsDeployStatusMsg{catalogueErr: errors.New("offline")},
			want: "catalogue: offline",
		},
	}

	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			err := summariseProblems(test.msg)
			if err == nil {
				t.Fatal("expected an error, got nil")
			}

			if err.Error() != test.want {
				t.Errorf("error = %q, want %q", err.Error(), test.want)
			}
		})
	}
}

func TestGetNumServersAndRecipes(t *testing.T) {
	tests := []struct {
		name        string
		apps        []config.App
		wantServers int
		wantRecipes int
	}{
		{
			name: "empty",
		},
		{
			name: "deduplicated",
			apps: []config.App{
				testApp("a.com", "srv1", "r1", "s1"),
				testApp("b.com", "srv1", "r1", "s2"),
				testApp("c.com", "srv2", "r2", "s3"),
			},
			wantServers: 2,
			wantRecipes: 2,
		},
	}

	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			servers, recipes := getNumServersAndRecipes(test.apps)
			if servers != test.wantServers {
				t.Errorf("servers = %v, want %v", servers, test.wantServers)
			}
			if recipes != test.wantRecipes {
				t.Errorf("recipes = %v, want %v", recipes, test.wantRecipes)
			}
		})
	}
}

func TestVisibleAppsCountsFiltered(t *testing.T) {
	apps := []config.App{
		testApp("a.com", "srv1", "r1", "s1"),
		testApp("b.com", "srv2", "r2", "s2"),
	}

	m := testModel(apps)
	m.numApps = len(apps)
	m.updateCount()

	if m.numFilteredApps != 2 {
		t.Errorf("numFilteredApps = %v, want 2", m.numFilteredApps)
	}

	m, _ = send(t, m, '/')
	m, _ = send(t, m, 'a')

	if !m.table.GetIsFilterActive() {
		t.Fatal("expected the filter to be active")
	}

	if got := visibleApps(&m); len(got) != 1 || got[0].Domain != "a.com" {
		t.Errorf("visibleApps = %v, want just a.com", got)
	}
}

func TestNewFlagSetLongForms(t *testing.T) {
	tests := []struct {
		arg         string
		wantHelp    bool
		wantVersion bool
	}{
		{arg: "-h", wantHelp: true},
		{arg: "--help", wantHelp: true},
		{arg: "-v", wantVersion: true},
		{arg: "--version", wantVersion: true},
	}

	for _, test := range tests {
		t.Run(test.arg, func(t *testing.T) {
			var helpFlag bool
			var versionFlag bool

			fs := newFlagSet(&helpFlag, &versionFlag)
			fs.SetOutput(io.Discard)

			if err := fs.Parse([]string{test.arg}); err != nil {
				t.Fatalf("unexpected error: %s", err)
			}

			if helpFlag != test.wantHelp {
				t.Errorf("help = %v, want %v", helpFlag, test.wantHelp)
			}

			if versionFlag != test.wantVersion {
				t.Errorf("version = %v, want %v", versionFlag, test.wantVersion)
			}
		})
	}
}

func TestNewFlagSetRejectsUnknownFlag(t *testing.T) {
	var helpFlag bool
	var versionFlag bool

	fs := newFlagSet(&helpFlag, &versionFlag)
	fs.SetOutput(io.Discard)

	if err := fs.Parse([]string{"--nope"}); err == nil {
		t.Error("expected an error for an unknown flag")
	}
}

func TestLabelKey(t *testing.T) {
	if got, want := labelKey("myapp_com_example", "version"), "coop-cloud.myapp_com_example.version"; got != want {
		t.Errorf("labelKey = %q, want %q", got, want)
	}
}

// deployedStatus is a fully populated status for a deployed stack.
func deployedStatus(name string) map[string]string {
	return map[string]string{
		keyStatus:       "deployed",
		keyVersion:      "1.0.0",
		keyUpdates:      "✅",
		keyChaos:        "false",
		keyChaosVersion: "abc123",
		keyAutoUpdate:   "true",
	}
}

func TestUpdateAppliesAppsDeployStatus(t *testing.T) {
	const name = "myapp_com_example"

	m := testModel([]config.App{testApp("a.com", "srv", "myrecipe", name)})
	m.pollingStatus = true

	m, _ = send(t, m, 'j') // any key, to prove the poll result lands

	updated, _ := m.Update(appsDeployStatusMsg{
		statuses: map[string]map[string]string{name: deployedStatus(name)},
	})
	m = updated.(model)

	if m.pollingStatus {
		t.Error("expected polling to have stopped")
	}

	if m.err != nil {
		t.Errorf("unexpected error banner: %v", m.err)
	}

	row := rowFor(t, m.table)

	for key, want := range deployedStatus(name) {
		if got := row.Data[key]; got != want {
			t.Errorf("%s = %q, want %q", key, got, want)
		}
	}
}

func TestUpdateReportsServerErrors(t *testing.T) {
	const name = "myapp_com_example"

	m := testModel([]config.App{testApp("a.com", "srv", "myrecipe", name)})

	updated, _ := m.Update(appsDeployStatusMsg{
		statuses:     map[string]map[string]string{name: deployedStatus(name)},
		serverErrors: map[string]error{"broken": errors.New("ssh: no route")},
	})
	m = updated.(model)

	if m.err == nil {
		t.Fatal("expected an error banner for an unreachable server")
	}

	if want := "broken: ssh: no route"; m.err.Error() != want {
		t.Errorf("error = %q, want %q", m.err.Error(), want)
	}

	// The reachable server's status is still rendered alongside the banner.
	if got := rowFor(t, m.table).Data[keyVersion]; got != "1.0.0" {
		t.Errorf("version = %q, want %q", got, "1.0.0")
	}
}

func TestUpdateClearsErrorOnKeypress(t *testing.T) {
	m := testModel([]config.App{testApp("a.com", "srv", "myrecipe", "s")})
	m.err = errors.New("something went wrong")

	m, _ = send(t, m, 'j')

	if m.err != nil {
		t.Errorf("expected the banner to be dismissed, got %v", m.err)
	}
}

func TestUpdateStartsPolling(t *testing.T) {
	m := testModel([]config.App{testApp("a.com", "srv", "myrecipe", "s")})

	m, cmd := send(t, m, 's')

	if !m.pollingStatus {
		t.Error("expected polling to have started")
	}

	if containsQuit(cmd) {
		t.Error("pressing s must not quit")
	}

	// A second s while polling is ignored rather than starting a duplicate.
	polling, _ := send(t, m, 's')
	if !polling.pollingStatus {
		t.Error("expected polling to still be in progress")
	}
}

func TestUpdateResizes(t *testing.T) {
	m := testModel([]config.App{testApp("a.com", "srv", "myrecipe", "s")})

	updated, _ := m.Update(tea.WindowSizeMsg{Width: 40, Height: 4})
	m = updated.(model)

	if got := m.table.PageSize(); got != 1 {
		t.Errorf("page size = %v, want 1 for a 4 row terminal", got)
	}

	if !strings.Contains(m.table.View(), "a.com") {
		t.Errorf("expected the row to survive a resize to 4 rows:\n%v", m.table.View())
	}
}

// TestGetApps exercises the local-first data path against a fake ~/.abra.
func TestGetApps(t *testing.T) {
	dir := t.TempDir()

	originalServers := config.SERVERS_DIR
	t.Cleanup(func() { config.SERVERS_DIR = originalServers })

	for _, app := range []struct {
		server string
		name   string
		body   string
	}{
		{server: "srvB", name: "zebra.com", body: "DOMAIN=zebra.com\nTYPE=recipeZ\n"},
		{server: "srvB", name: "alpha.com", body: "DOMAIN=alpha.com\nRECIPE=recipeA\n"},
		{server: "srvA", name: "middle.net", body: "DOMAIN=middle.net\nTYPE=recipeA\n"},
	} {
		serverDir := filepath.Join(dir, "servers", app.server)
		if err := os.MkdirAll(serverDir, 0o755); err != nil {
			t.Fatal(err)
		}

		path := filepath.Join(serverDir, app.name+".env")
		if err := os.WriteFile(path, []byte(app.body), 0o644); err != nil {
			t.Fatal(err)
		}
	}

	config.SERVERS_DIR = filepath.Join(dir, "servers")

	apps, err := getApps()
	if err != nil {
		t.Fatalf("getApps: %s", err)
	}

	var domains []string
	for _, app := range apps {
		domains = append(domains, app.Domain)
	}

	want := []string{"alpha.com", "middle.net", "zebra.com"}
	if !reflect.DeepEqual(domains, want) {
		t.Errorf("domains = %v, want %v sorted by name", domains, want)
	}

	if got, recipes := getNumServersAndRecipes(apps); got != 2 || recipes != 2 {
		t.Errorf("got %v servers and %v recipes, want 2 and 2", got, recipes)
	}
}

func TestView(t *testing.T) {
	m := testModel([]config.App{testApp("a.com", "srv", "r", "s")})
	m.numFilteredApps = 1
	m.numFilteredServers = 1
	m.numFilteredRecipes = 1

	view := m.View()

	for _, want := range []string{"Servers: 1, Apps: 1, Recipes: 1", "a.com", "cctuip " + version} {
		if !strings.Contains(view, want) {
			t.Errorf("view is missing %q:\n%v", want, view)
		}
	}

	if strings.Contains(view, "⚠") {
		t.Errorf("view should have no error banner:\n%v", view)
	}

	m.err = errors.New("boom")

	if !strings.Contains(m.View(), "⚠ boom") {
		t.Errorf("view is missing the error banner:\n%v", m.View())
	}

	m.pollingStatus = true

	if !strings.Contains(m.View(), "querying app status") {
		t.Errorf("view is missing the polling indicator:\n%v", m.View())
	}
}