package stacks

import (
	"bytes"
	"context"
	"fmt"
	"log"
	"os"
	"path/filepath"
	"strings"
	"sync"
	"testing"
	"time"
)

// R-717 — the command form's "open" twin: the household's 15-minute window reopens an app's own database-held
// sign-up switch, and the loop closes it again. Never reaches Docker: afterLoadFn is the compose-exec seam.

const cmdYml = "display_name: Gated App\nsetup_gate: true\nsignup_block: \"PathPrefix(`/signup`)\"\n" +
	"after_setup:\n  service: gapp\n  command: [\"sh\", \"-c\", \"close-signup\"]\n  success: \"SIGNUP-CLOSED\"\n" +
	"  open_command: [\"sh\", \"-c\", \"open-signup\"]\n  open_success: \"SIGNUP-OPENED\"\n" +
	"deploy_fields:\n  - env_var: DOMAIN\n    type: domain\n  - env_var: SUBDOMAIN\n    type: subdomain\n    default: gapp\n"

// fakeSwitch is the app's own database switch behind the exec seam.
type fakeSwitch struct {
	mu        sync.Mutex
	open      bool
	opens     int
	closes    int
	failOpen  bool
	failClose bool
	onOpen    func() // runs after the switch opened, before the command returns (a crash point)
}

func (f *fakeSwitch) exec(dir string, args ...string) (string, error) {
	f.mu.Lock()
	defer f.mu.Unlock()
	last := args[len(args)-1]
	switch last {
	case "open-signup":
		f.opens++
		if f.failOpen {
			return "error: database is locked", fmt.Errorf("exit 1")
		}
		f.open = true
		if f.onOpen != nil {
			f.onOpen()
		}
		return "SIGNUP-OPENED", nil
	case "close-signup":
		f.closes++
		if f.failClose {
			return "error: database is locked", fmt.Errorf("exit 1")
		}
		f.open = false
		return "SIGNUP-CLOSED", nil
	}
	return "", fmt.Errorf("unexpected exec %v", args)
}

func (f *fakeSwitch) counts() (opens, closes int, open bool) {
	f.mu.Lock()
	defer f.mu.Unlock()
	return f.opens, f.closes, f.open
}

func wireCmdManager(m *Manager, f *fakeSwitch) *bytes.Buffer {
	m.afterSetupSync = true
	m.afterSetupUpFn = func(string) error { return nil }
	m.afterLoadFn = f.exec
	var buf bytes.Buffer
	m.logger = log.New(&buf, "", 0)
	return &buf
}

func cmdManager(t *testing.T, yml string) (*Manager, *fakeSwitch, *bytes.Buffer, string) {
	t.Helper()
	m := gateManager(t, yml)
	f := &fakeSwitch{}
	buf := wireCmdManager(m, f)
	dir := closedGate(t, m)
	must(t, m.OpenSetupGate("gapp", SetupGateByHousehold)) // the first close
	if _, closes, open := f.counts(); closes != 1 || open {
		t.Fatalf("the gate opening did not close the app's own switch: closes=%d open=%v", closes, open)
	}
	return m, f, buf, dir
}

// The window runs open_command once; the window's end runs command once; the switch ends closed.
// COMPANION RED-PROOF (felhom.eu audits/design-build-2026-10-06/E/red-open-then-close.txt): drop the open_command
// run in liftNativeLock (the code before R-717) → "the window did not open the app's own switch" fails.
func TestAfterSetupR717_OpenThenCloseEachRunOnce(t *testing.T) {
	m, f, _, dir := cmdManager(t, cmdYml)
	_, err := m.OpenSignupWindow("gapp")
	must(t, err)
	if opens, closes, open := f.counts(); opens != 1 || closes != 1 || !open {
		t.Fatalf("the window did not open the app's own switch: opens=%d closes=%d open=%v", opens, closes, open)
	}
	if c := LoadAppConfig(dir); c.SetupGate.NativeLock != NativeLockLifted || c.AfterSetup == nil || !c.AfterSetup.OK {
		t.Fatalf("after the open: native=%q record=%+v", c.SetupGate.NativeLock, c.AfterSetup)
	}
	m.SetupGateTick() // inside the window: nothing closes
	if _, closes, open := f.counts(); closes != 1 || !open {
		t.Fatalf("the loop closed the switch INSIDE the window: closes=%d open=%v", closes, open)
	}
	later := time.Now().Add(signupWindow + time.Minute)
	m.updateNowFn = func() time.Time { return later }
	m.SetupGateTick()
	m.SetupGateTick() // a second pass must not run it again
	if opens, closes, open := f.counts(); opens != 1 || closes != 2 || open {
		t.Fatalf("after the window: opens=%d closes=%d open=%v (want 1 open, 1 more close, closed)", opens, closes, open)
	}
	if c := LoadAppConfig(dir); c.SetupGate.NativeLock != NativeLockApplied || !c.AfterSetup.OK {
		t.Fatalf("after the window: native=%q record=%+v", c.SetupGate.NativeLock, c.AfterSetup)
	}
}

// A box restart inside the window ends CLOSED — even when the controller died between the open command and its
// record (the worst moment: the switch is open, nothing says so yet).
// COMPANION RED-PROOF (red-restart-mid-open.txt): drop the "opening" mark in liftNativeLock → the disk at the crash
// says "applied", the restarted loop never closes, "a restart left sign-up OPEN" fails.
func TestAfterSetupR717_ARestartInsideTheWindowEndsClosed(t *testing.T) {
	m, f, _, dir := cmdManager(t, cmdYml)
	var atCrash []byte
	f.onOpen = func() { // the controller dies here: copy app.yaml as it is on disk at this moment
		b, err := os.ReadFile(filepath.Join(dir, "app.yaml"))
		must(t, err)
		atCrash = b
	}
	_, err := m.OpenSignupWindow("gapp")
	must(t, err)
	if atCrash == nil {
		t.Fatal("the open command never ran")
	}
	must(t, os.WriteFile(filepath.Join(dir, "app.yaml"), atCrash, 0o600)) // the disk the restart finds

	// The restart: a new Manager over the same paths, the startup tick (RunSetupGateLoop's first pass).
	m2, err := NewManager(m.cfg, log.New(&bytes.Buffer{}, "", 0))
	must(t, err)
	must(t, m2.ScanStacks())
	buf := wireCmdManager(m2, f)
	m2.mu.Lock()
	m2.stacks["gapp"].State = StateRunning
	m2.mu.Unlock()
	later := time.Now().Add(signupWindow + time.Minute)
	m2.updateNowFn = func() time.Time { return later }
	m2.SetupGateTick()
	if _, _, open := f.counts(); open {
		t.Fatalf("a restart left sign-up OPEN in the app past its window (record at the crash: native=%q)\n%s",
			LoadAppConfig(dir).SetupGate.NativeLock, buf.String())
	}
	if c := LoadAppConfig(dir); c.SetupGate.NativeLock != NativeLockApplied {
		t.Fatalf("after the restart: native=%q", c.SetupGate.NativeLock)
	}
}

// An open command that fails leaves the switch closed, records step "open", and says so in the log.
// COMPANION RED-PROOF (red-failed-open.txt): drop the re-close (applyNativeLock(true, …)) in liftNativeLock's
// failure branch → the half-opened switch stays open → "a failed open left the switch OPEN" fails.
func TestAfterSetupR717_AFailedOpenStaysClosedAndSaysSo(t *testing.T) {
	m, f, buf, dir := cmdManager(t, cmdYml)
	f.onOpen = nil
	f.mu.Lock()
	f.failOpen = true
	f.open = true // the command half-ran: it flipped the switch, then failed
	f.mu.Unlock()
	_, err := m.OpenSignupWindow("gapp")
	must(t, err)
	if _, _, open := f.counts(); open {
		t.Fatalf("a failed open left the switch OPEN\n%s", buf.String())
	}
	c := LoadAppConfig(dir)
	if c.SetupGate.NativeLock == NativeLockLifted || c.SetupGate.NativeLock == NativeLockOpening {
		t.Fatalf("a failed open recorded native=%q", c.SetupGate.NativeLock)
	}
	if c.AfterSetup == nil || c.AfterSetup.OK || c.AfterSetup.Step != afterSetupStepOpen || !strings.Contains(c.AfterSetup.Detail, "could not be opened") {
		t.Fatalf("the failure is not recorded: %+v", c.AfterSetup)
	}
	if !strings.Contains(buf.String(), "[ERROR]") || !strings.Contains(buf.String(), "could NOT be opened") {
		t.Fatalf("the failure is not logged:\n%s", buf.String())
	}
}

// A close that fails at the window's end is logged loudly, never recorded as closed, and retried by the loop.
// COMPANION RED-PROOF (red-failed-close-retry.txt): use the 30-minute nativeLockRetry after a window too → "the loop
// did not retry the close" fails.
func TestAfterSetupR717_AFailedCloseIsRetriedNotTrusted(t *testing.T) {
	m, f, buf, dir := cmdManager(t, cmdYml)
	_, err := m.OpenSignupWindow("gapp")
	must(t, err)
	f.mu.Lock()
	f.failClose = true
	f.mu.Unlock()
	t0 := time.Now().Add(signupWindow + time.Minute)
	m.updateNowFn = func() time.Time { return t0 }
	m.SetupGateTick()
	c := LoadAppConfig(dir)
	if c.SetupGate.NativeLock == NativeLockApplied || c.AfterSetup.OK {
		t.Fatalf("a failed close was recorded as closed: native=%q record=%+v", c.SetupGate.NativeLock, c.AfterSetup)
	}
	if !strings.Contains(buf.String(), "may still be OPEN past the household's window") {
		t.Fatalf("the failed close is not loud:\n%s", buf.String())
	}
	f.mu.Lock()
	f.failClose = false
	f.mu.Unlock()
	t1 := t0.Add(nativeLockOpenRetry + time.Second)
	m.updateNowFn = func() time.Time { return t1 }
	m.SetupGateTick()
	if _, _, open := f.counts(); open {
		t.Fatal("the loop did not retry the close")
	}
	if c := LoadAppConfig(dir); c.SetupGate.NativeLock != NativeLockApplied || !c.AfterSetup.OK {
		t.Fatalf("after the retry: native=%q record=%+v", c.SetupGate.NativeLock, c.AfterSetup)
	}
}

// After a successful app update, the loop runs the close again.
// COMPANION RED-PROOF (red-close-after-update.txt): drop markNativeLockForReapply in verifyAndConclude → the close
// does not run again → "the update did not re-run the close" fails.
func TestAfterSetupR717_TheCloseRunsAgainAfterAnUpdate(t *testing.T) {
	m, f, _, dir := cmdManager(t, cmdYml)
	m.updateHealthFn = func(context.Context, string, time.Duration) (bool, string) { return true, "ok" }
	f.mu.Lock()
	f.open = true // the update brought a database whose switch is open
	f.mu.Unlock()
	m.verifyAndConclude(context.Background(), "gapp", dir, nil, UpdateRestorePoint{}, time.Now(), &updateJournalEntry{})
	m.mu.Lock()
	m.stacks["gapp"].State = StateRunning
	m.mu.Unlock()
	m.SetupGateTick()
	if _, closes, open := f.counts(); closes != 2 || open {
		t.Fatalf("the update did not re-run the close: closes=%d open=%v", closes, open)
	}
	if c := LoadAppConfig(dir); c.SetupGate.NativeLock != NativeLockApplied {
		t.Fatalf("after the update: native=%q", c.SetupGate.NativeLock)
	}
}

// A template that closes by command but has no open_command: the window opens the address only, the app's switch
// stays closed, and the log says so ONCE (two presses).
// COMPANION RED-PROOF (red-no-open-command-logs-once.txt): drop the LoadOrStore guard → logged twice, fails.
func TestAfterSetupR717_NoOpenCommandLogsOnceAndKeepsTheWindow(t *testing.T) {
	yml := strings.Replace(cmdYml, "  open_command: [\"sh\", \"-c\", \"open-signup\"]\n  open_success: \"SIGNUP-OPENED\"\n", "", 1)
	m, f, buf, dir := cmdManager(t, yml)
	for i := 0; i < 2; i++ {
		_, err := m.OpenSignupWindow("gapp")
		must(t, err)
	}
	if opens, closes, open := f.counts(); opens != 0 || closes != 1 || open {
		t.Fatalf("opens=%d closes=%d open=%v", opens, closes, open)
	}
	if n := strings.Count(buf.String(), "has no open_command"); n != 1 {
		t.Fatalf("the missing open_command was logged %d times, want once:\n%s", n, buf.String())
	}
	if _, err := os.Stat(m.signupBlockPath("gapp")); !os.IsNotExist(err) {
		t.Fatal("the window did not open the address")
	}
	if c := LoadAppConfig(dir); c.SetupGate.NativeLock != NativeLockApplied {
		t.Fatalf("native=%q — nothing of the app's own was opened", c.SetupGate.NativeLock)
	}
}

// The env form keeps today's behaviour beside an open_command: env lifted AND the command run.
func TestAfterSetupR717_EnvAndOpenCommandTogether(t *testing.T) {
	yml := strings.Replace(cmdYml, "after_setup:\n", "after_setup:\n  env:\n    SIGNUP_CLOSED: \"true\"\n", 1)
	m := gateManager(t, yml)
	must(t, os.WriteFile(filepath.Join(m.cfg.Paths.StacksDir, "gapp", "docker-compose.yml"), []byte(nativeCompose), 0o644))
	must(t, m.ScanStacks())
	f := &fakeSwitch{}
	wireCmdManager(m, f)
	dir := closedGate(t, m)
	must(t, m.OpenSetupGate("gapp", SetupGateByHousehold))
	_, err := m.OpenSignupWindow("gapp")
	must(t, err)
	c := LoadAppConfig(dir)
	if opens, _, open := f.counts(); c.Env["SIGNUP_CLOSED"] != "" || opens != 1 || !open || c.SetupGate.NativeLock != NativeLockLifted {
		t.Fatalf("window: env=%q opens=%d open=%v native=%q", c.Env["SIGNUP_CLOSED"], opens, open, c.SetupGate.NativeLock)
	}
	later := time.Now().Add(signupWindow + time.Minute)
	m.updateNowFn = func() time.Time { return later }
	m.SetupGateTick()
	c = LoadAppConfig(dir)
	if _, _, open := f.counts(); c.Env["SIGNUP_CLOSED"] != "true" || open || c.SetupGate.NativeLock != NativeLockApplied {
		t.Fatalf("after: env=%q open=%v native=%q", c.Env["SIGNUP_CLOSED"], open, c.SetupGate.NativeLock)
	}
}