package main

import (
	"bytes"
	"context"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"proxyctl/internal/profile"
	"proxyctl/internal/target"
)

func TestVersionOutputIsHumanAndScriptFriendly(t *testing.T) {
	previous := version
	version = "v1.2.3"
	t.Cleanup(func() { version = previous })

	var output bytes.Buffer
	if err := run([]string{"version"}, strings.NewReader(""), &output); err != nil {
		t.Fatalf("run version: %v", err)
	}
	if got, want := output.String(), "proxyctl version v1.2.3\n"; got != want {
		t.Fatalf("human version output = %q, want %q", got, want)
	}

	output.Reset()
	if err := run([]string{"version", "--short"}, strings.NewReader(""), &output); err != nil {
		t.Fatalf("run short version: %v", err)
	}
	if got, want := output.String(), "v1.2.3\n"; got != want {
		t.Fatalf("script version output = %q, want %q", got, want)
	}
}

func TestVersionDoesNotRequireUserOrTargetResolution(t *testing.T) {
	var output bytes.Buffer
	if err := runWithEnvironmentAndTargets([]string{"version", "--short"}, strings.NewReader(""), &output, failingIdentityEnvironment{}, nil, "", nil); err != nil {
		t.Fatalf("version depended on runtime environment: %v", err)
	}
}

func TestProductionCompositionRegistersAPTContainerGNOMEAndDaemonTargets(t *testing.T) {
	home := t.TempDir()
	environment := commandEnvironment{identity: profile.UserIdentity{Username: "tester", HomeDir: home, UID: os.Getuid(), GID: os.Getgid()}, env: map[string]string{"SHELL": "/bin/bash"}}
	targets, err := productionTargets(environment)
	if err != nil {
		t.Fatal(err)
	}
	var ids []string
	for _, adapter := range targets {
		ids = append(ids, adapter.ID())
		if _, ok := adapter.(target.Diagnosable); !ok {
			t.Errorf("production Target %s does not contribute doctor checks", adapter.ID())
		}
	}
	want := []string{"apt", "docker-containers", "gnome", "docker-daemon"}
	if strings.Join(ids, ",") != strings.Join(want, ",") {
		t.Fatalf("production Target IDs = %#v, want %#v", ids, want)
	}
}

func TestDefaultInvocationStartsTUIWithNoProfileState(t *testing.T) {
	t.Setenv("XDG_CONFIG_HOME", t.TempDir())
	var output bytes.Buffer
	if err := runWithSystemTargets(nil, strings.NewReader("q"), &output, []target.Target{}); err != nil {
		t.Fatalf("run proxyctl: %v", err)
	}
	if !strings.Contains(output.String(), "No Active Profile") {
		t.Fatalf("default TUI output missing no-Profile state: %q", output.String())
	}
}

func TestDefaultInvocationUsesAlternateScreenAndRestoresItOnExit(t *testing.T) {
	t.Setenv("XDG_CONFIG_HOME", t.TempDir())
	var output bytes.Buffer
	if err := runWithSystemTargets(nil, strings.NewReader("q"), &output, []target.Target{}); err != nil {
		t.Fatalf("run proxyctl: %v", err)
	}
	frame := output.String()
	if !strings.Contains(frame, "\x1b[?1049h") {
		t.Fatalf("default TUI did not enter the alternate screen: %q", frame)
	}
	if !strings.Contains(frame, "\x1b[?1049l") {
		t.Fatalf("default TUI did not restore the previous screen: %q", frame)
	}
}

type blockingDetectionTarget struct {
	started chan struct{}
	release chan struct{}
}

func (t *blockingDetectionTarget) ID() string { return "blocking-test" }
func (t *blockingDetectionTarget) Description() target.Description {
	return target.Description{Name: "Blocking test Target"}
}
func (t *blockingDetectionTarget) Availability(context.Context) target.Availability {
	return target.Availability{Available: true}
}
func (t *blockingDetectionTarget) Inspect(context.Context, *profile.Profile) target.Inspection {
	return target.Inspection{State: target.Disabled}
}
func (t *blockingDetectionTarget) Confirmation(bool) string { return "" }
func (t *blockingDetectionTarget) SetDesired(context.Context, bool, *profile.Profile) target.OperationResult {
	return target.OperationResult{}
}
func (t *blockingDetectionTarget) Detect(context.Context, *profile.Profile) target.Detection {
	select {
	case t.started <- struct{}{}:
	default:
	}
	<-t.release
	return target.Detection{
		Availability: target.Availability{Available: true, Evidence: "hermetic test Target"},
		Inspection:   target.Inspection{State: target.Disabled, Evidence: "no configuration"},
	}
}

func TestDeferredExitCompletesSafelyAndRestoresAlternateScreen(t *testing.T) {
	t.Setenv("XDG_CONFIG_HOME", t.TempDir())
	adapter := &blockingDetectionTarget{started: make(chan struct{}, 1), release: make(chan struct{})}
	var output bytes.Buffer
	done := make(chan error, 1)
	go func() {
		done <- runWithSystemTargets(nil, strings.NewReader("q"), &output, []target.Target{adapter})
	}()

	select {
	case <-adapter.started:
	case err := <-done:
		t.Fatalf("TUI exited before progressive startup began: %v", err)
	case <-time.After(5 * time.Second):
		t.Fatal("progressive startup did not reach the hermetic Target")
	}
	select {
	case err := <-done:
		t.Fatalf("deferred exit returned before safe operation completion: %v", err)
	case <-time.After(50 * time.Millisecond):
	}
	close(adapter.release)
	select {
	case err := <-done:
		if err != nil {
			t.Fatalf("run proxyctl: %v", err)
		}
	case <-time.After(5 * time.Second):
		t.Fatal("TUI did not exit after safe operation completion")
	}

	frame := output.String()
	enter := strings.Index(frame, "\x1b[?1049h")
	leave := strings.LastIndex(frame, "\x1b[?1049l")
	if enter < 0 || leave <= enter {
		t.Fatalf("deferred exit did not enter and restore the alternate screen in order: %q", frame)
	}
}

func TestDefaultInvocationLoadsPersistedActiveProfile(t *testing.T) {
	xdg := t.TempDir()
	t.Setenv("XDG_CONFIG_HOME", xdg)
	writeConfig(t, filepath.Join(xdg, "proxyctl", "profiles.json"), `{
  "profiles": [{"name":"office","mode":"single","singleUrl":"http://proxy.example:8080","httpUrl":"http://proxy.example:8080","httpsUrl":"http://proxy.example:8080","allUrl":"http://proxy.example:8080"}],
  "activeProfile": "office"
}`)
	var output bytes.Buffer
	if err := runWithSystemTargets(nil, strings.NewReader("q"), &output, []target.Target{}); err != nil {
		t.Fatalf("run proxyctl: %v", err)
	}
	if !strings.Contains(output.String(), "Active Profile: office") {
		t.Fatalf("default TUI output missing Active Profile: %q", output.String())
	}
}

func writeConfig(t *testing.T, path, contents string) {
	t.Helper()
	if err := os.MkdirAll(filepath.Dir(path), 0o700); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(path, []byte(contents), 0o600); err != nil {
		t.Fatal(err)
	}
}