package main

import (
	"net/http"
	"os"
	"path/filepath"
	"testing"
	"time"
)

// Major version pinning (update_major + releaseEntry.Semver): minors and
// patches follow the channel, a head crossing the pinned major is held —
// halt-and-notify, never a silent auto-upgrade across a breaking boundary.

// seedSemvers stamps semvers onto feed versions for this test and cleans up.
func seedSemvers(t *testing.T, m map[string]string) {
	t.Helper()
	for v, sv := range m {
		feedSemvers[v] = sv
	}
	t.Cleanup(func() {
		for v := range m {
			delete(feedSemvers, v)
		}
	})
}

func TestSemverHelpers(t *testing.T) {
	if n, ok := semverMajor("2.14.3"); !ok || n != 2 {
		t.Fatalf("semverMajor(2.14.3) = %d, %v", n, ok)
	}
	for _, bad := range []string{"", "2", "2.1", "v2.1.3", "2.1.3-rc1", "2.1.3.4", "x.y.z"} {
		if _, ok := semverMajor(bad); ok {
			t.Errorf("semverMajor(%q) accepted", bad)
		}
	}
	for _, good := range []string{"", "0", "1", "12"} {
		if !validMajor(good) {
			t.Errorf("validMajor(%q) rejected", good)
		}
	}
	for _, bad := range []string{"-1", "1.0", "one", "99999"} {
		if validMajor(bad) {
			t.Errorf("validMajor(%q) accepted", bad)
		}
	}
}

func TestValidateManifestSemver(t *testing.T) {
	ok := entryFor("new1234")
	ok.Semver = "1.2.3"
	m := &releaseManifest{Schema: 1, GeneratedAt: time.Now(), Channels: map[string]releaseEntry{"stable": ok}}
	if err := validateManifest(m); err != nil {
		t.Fatalf("valid semver rejected: %v", err)
	}
	bad := entryFor("new1234")
	bad.Semver = "not-a-version"
	m.Channels["stable"] = bad
	if err := validateManifest(m); err == nil {
		t.Fatal("garbage semver accepted")
	}
}

func TestMajorHoldSemantics(t *testing.T) {
	e := func(sv string) releaseEntry { return releaseEntry{Version: "abc1234", Semver: sv} }
	if hold := majorHold("", e("2.0.0")); hold != "" {
		t.Fatalf("no pin but held: %s", hold)
	}
	if hold := majorHold("1", e("1.9.9")); hold != "" {
		t.Fatalf("within-major held: %s", hold)
	}
	if hold := majorHold("2", e("1.0.0")); hold != "" {
		t.Fatalf("older major held (pull-backs must pass): %s", hold)
	}
	if hold := majorHold("1", e("2.0.0")); hold == "" {
		t.Fatal("crossing major not held")
	}
	// Fail closed: a pinned instance never takes an unlabelled release.
	if hold := majorHold("1", e("")); hold == "" {
		t.Fatal("semver-less release not held under a major pin")
	}
}

func TestUpdatePassMajorPinHoldsCrossing(t *testing.T) {
	withTempOpt(t)
	zeroBake(t) // bake has its own tests; this one is about the major gate
	calls := stubSystemctl(t)
	shrink := deployHealthTimeout
	deployHealthTimeout = 2 * time.Second
	t.Cleanup(func() { deployHealthTimeout = shrink })

	seedSemvers(t, map[string]string{"v2head99": "2.0.0"})
	_, setChannels := startFeed(t, map[string]string{"v2head99": "v2-binary"})
	setChannels(map[string]string{"stable": "v2head99"})

	reg, err := openRegistry(filepath.Join(t.TempDir(), "reg.db"))
	if err != nil {
		t.Fatal(err)
	}
	s1 := startFakeInstance(t, "h1.example.com", http.StatusOK,
		updatePrefs{AutoUpdate: true, AutoDownload: true, Channel: "stable", Major: "1"}, "")
	seedInstance(t, reg, "h1.example.com", s1, "old1111")

	if err := updatePass(reg, "lchat@", false, false); err != nil {
		t.Fatal(err)
	}
	if v, _ := liveVersion("h1.example.com"); v != "old1111" {
		t.Fatalf("v2 installed across a major-1 pin: live = %q", v)
	}
	if _, err := os.Stat(versionBinPath("v2head99")); !os.IsNotExist(err) {
		t.Fatal("crossing release was downloaded")
	}
	if len(*calls) != 0 {
		t.Fatalf("restarts despite the major hold: %v", *calls)
	}
}

func TestUpdatePassMajorPinFollowsWithinMajor(t *testing.T) {
	withTempOpt(t)
	zeroBake(t)
	stubSystemctl(t)
	shrink := deployHealthTimeout
	deployHealthTimeout = 2 * time.Second
	t.Cleanup(func() { deployHealthTimeout = shrink })

	seedSemvers(t, map[string]string{"v1patch7": "1.4.2"})
	_, setChannels := startFeed(t, map[string]string{"v1patch7": "patch-binary"})
	setChannels(map[string]string{"stable": "v1patch7"})

	reg, err := openRegistry(filepath.Join(t.TempDir(), "reg.db"))
	if err != nil {
		t.Fatal(err)
	}
	s1 := startFakeInstance(t, "h1.example.com", http.StatusOK,
		updatePrefs{AutoUpdate: true, AutoDownload: true, Channel: "stable", Major: "1"}, "")
	seedInstance(t, reg, "h1.example.com", s1, "old1111")

	if err := updatePass(reg, "lchat@", false, false); err != nil {
		t.Fatal(err)
	}
	if v, _ := liveVersion("h1.example.com"); v != "v1patch7" {
		t.Fatalf("within-major release held: live = %q", v)
	}
}

func TestUpdatePassMajorPinHoldsSemverlessHead(t *testing.T) {
	withTempOpt(t)
	zeroBake(t)
	stubSystemctl(t)

	// No seedSemvers: the head carries no semver at all — the pin fails closed.
	_, setChannels := startFeed(t, map[string]string{"nolabel1": "content"})
	setChannels(map[string]string{"stable": "nolabel1"})

	reg, err := openRegistry(filepath.Join(t.TempDir(), "reg.db"))
	if err != nil {
		t.Fatal(err)
	}
	s1 := startFakeInstance(t, "h1.example.com", http.StatusOK,
		updatePrefs{AutoUpdate: true, AutoDownload: true, Channel: "stable", Major: "1"}, "")
	seedInstance(t, reg, "h1.example.com", s1, "old1111")

	if err := updatePass(reg, "lchat@", false, false); err != nil {
		t.Fatal(err)
	}
	if v, _ := liveVersion("h1.example.com"); v != "old1111" {
		t.Fatalf("semver-less head installed under a major pin: live = %q", v)
	}
}

func TestUpdatePassMajorPinHoldsHibernating(t *testing.T) {
	withTempOpt(t)
	zeroBake(t)
	calls := stubSystemctl(t)

	oldData := instanceDataDir
	instanceDataDir = t.TempDir()
	t.Cleanup(func() { instanceDataDir = oldData })

	seedSemvers(t, map[string]string{"v2head99": "2.0.0"})
	_, setChannels := startFeed(t, map[string]string{"v2head99": "v2-binary"})
	setChannels(map[string]string{"stable": "v2head99"})

	reg, err := openRegistry(filepath.Join(t.TempDir(), "reg.db"))
	if err != nil {
		t.Fatal(err)
	}
	src := filepath.Join(t.TempDir(), "old")
	writeFakeBinary(t, src, "old-binary")
	if err := stageVersion(src, "old1111"); err != nil {
		t.Fatal(err)
	}
	if err := pointLive("h1.hib", "old1111"); err != nil {
		t.Fatal(err)
	}
	if err := reg.upsert(Route{Host: "h1.hib", Kind: "instance", Status: "ready",
		Socket: filepath.Join(t.TempDir(), "no.sock"), Hibernate: true, Version: "old1111"}); err != nil {
		t.Fatal(err)
	}
	db, err := openDB(filepath.Join(instanceDataDir, "h1.hib.db"))
	if err != nil {
		t.Fatal(err)
	}
	if err := db.setConfig("update_major", "1"); err != nil {
		t.Fatal(err)
	}
	db.sql.Close()

	if err := updatePass(reg, "lchat@", false, false); err != nil {
		t.Fatal(err)
	}
	if v, _ := liveVersion("h1.hib"); v != "old1111" {
		t.Fatalf("hibernating host repointed across its major pin: live = %q", v)
	}
	if len(*calls) != 0 {
		t.Fatalf("systemctl touched: %v", *calls)
	}
}