package sync

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

	"gitea.dooplex.hu/admin/felhom-controller/internal/config"
)

func newTestSyncer(t *testing.T, repoURL string) *Syncer {
	t.Helper()
	dir := t.TempDir()
	cfg := &config.Config{}
	cfg.Git.RepoURL = repoURL
	cfg.Git.Branch = "main"
	cfg.Git.SyncInterval = "15m"
	cfg.Paths.DataDir = filepath.Join(dir, "data")
	cfg.Paths.StacksDir = filepath.Join(dir, "stacks")
	if err := os.MkdirAll(cfg.Paths.StacksDir, 0o755); err != nil {
		t.Fatal(err)
	}
	logger := log.New(os.Stderr, "", 0)
	return New(cfg, logger, func() error { return nil }, nil)
}

// T-C1 (campaign F3): a git subprocess must die with its context — the pre-fix
// exec.Command shape ignored the context entirely, so a hung remote parked the sync
// goroutine in cmd.Run() forever, holding `syncing=true` until a controller restart.
// Effect asserted: the returned error NAMES the context cause (not a generic git error),
// and the call returns promptly instead of running the command to completion.
func TestRunGitInDir_CancelledContextKillsSubprocess(t *testing.T) {
	s := newTestSyncer(t, "https://example.invalid/repo.git")

	ctx, cancel := context.WithCancel(context.Background())
	cancel() // already cancelled — the subprocess must not be allowed to run to completion

	start := time.Now()
	err := s.runGitInDir(ctx, "", "--version")
	elapsed := time.Since(start)

	if err == nil {
		t.Fatalf("expected an error from a cancelled context, got nil (git --version ran to completion — the pre-fix behavior)")
	}
	if !strings.Contains(err.Error(), context.Canceled.Error()) {
		t.Fatalf("error must name the context cause; got: %v", err)
	}
	if !strings.Contains(err.Error(), "deadline") && !strings.Contains(err.Error(), "killed") {
		t.Fatalf("error must say the subprocess was killed at the deadline; got: %v", err)
	}
	if elapsed > 5*time.Second {
		t.Fatalf("cancelled-context git call took %v — subprocess not killed promptly", elapsed)
	}
}

// T-C2 (campaign F3): a failed sync must release the single-flight `syncing` flag and a
// later TriggerSync (past the debounce) must EXECUTE — the campaign symptom was every
// subsequent sync refused with "Szinkronizálás már folyamatban". Uses a nonexistent local
// repo_url so git fails fast with no network.
func TestTriggerSync_FailureReleasesSyncingAndAllowsRetry(t *testing.T) {
	s := newTestSyncer(t, filepath.Join(t.TempDir(), "no-such-repo"))

	res := s.TriggerSync()
	if res.OK {
		t.Fatalf("sync against a nonexistent repo must fail; got OK with message %q", res.Message)
	}
	if !strings.Contains(res.Message, "Git hiba") {
		t.Fatalf("failure must carry the git error to the caller (no silent swallow); got %q", res.Message)
	}

	st := s.Status()
	if st.Syncing {
		t.Fatalf("`syncing` still true after a failed sync — the single-flight flag leaked (the F3 lockup)")
	}
	if st.LastStatus != "error" || st.LastError == "" {
		t.Fatalf("failed sync must be recorded: LastStatus=%q LastError=%q", st.LastStatus, st.LastError)
	}

	// Debounce window: an immediate retry is refused (existing behavior, unchanged).
	res2 := s.TriggerSync()
	if res2.OK || !strings.Contains(res2.Message, "Túl gyakori") {
		t.Fatalf("immediate retry should hit the 30s debounce; got OK=%v message=%q", res2.OK, res2.Message)
	}

	// Past the debounce (rewind lastSync directly — same-package seam), the retry must
	// EXECUTE: it reaches git again and fails with the git error, not a refusal message.
	s.mu.Lock()
	s.lastSync = time.Now().Add(-time.Minute)
	s.mu.Unlock()

	res3 := s.TriggerSync()
	if res3.OK {
		t.Fatalf("retry against the same nonexistent repo should still fail: %q", res3.Message)
	}
	if !strings.Contains(res3.Message, "Git hiba") {
		t.Fatalf("retry past the debounce must EXECUTE (git error expected); got refusal/other: %q", res3.Message)
	}
	if s.Status().Syncing {
		t.Fatal("`syncing` leaked after the retry")
	}
}