package host

import (
	"context"
	"encoding/json"
	"github.com/carlosframework/platform/internal/rootparticipation"
	"os"
	"path/filepath"
	"testing"
)

func updateParticipationFixture(t *testing.T) *rootparticipation.Ledger {
	t.Helper()
	disk := &rollbackDisk{dir: t.TempDir()}
	raw, _ := json.Marshal(rootparticipation.Census{Schema: 1, Box: "box", Enrollment: "en", Migration: 1, Revision: 1, LaunchRevision: 1, Complete: true})
	if err := disk.Write("census.json", raw); err != nil {
		t.Fatal(err)
	}
	return &rootparticipation.Ledger{State: disk, VerifyLaunches: func(context.Context, uint64) error { return nil }, ExcludeLaunches: func(ctx context.Context, fn func(context.Context) error) error { return fn(ctx) }}
}

func TestPlan14ExecutionSystemUpdateExclusion(t *testing.T) {
	for _, pending := range []bool{false, true} {
		t.Run(map[bool]string{true: "participating", false: "empty"}[pending], func(t *testing.T) {
			f := newApplyFixture(t, "stable", "old")
			f.a.regionHA = true
			f.a.participation = updateParticipationFixture(t)
			if pending {
				if err := f.a.participation.State.Write("shop.example.json", []byte("{\"Schema\":1,\"Status\":\"pending\"}")); err != nil {
					t.Fatal(err)
				}
			}
			mirror := filepath.Join(f.a.dataDir, ".hostexec")
			if err := os.MkdirAll(mirror, 0700); err != nil {
				t.Fatal(err)
			}
			if err := os.Remove(mirror); err != nil {
				t.Fatal(err)
			}
			err := f.a.beginExecutableChange(t.Context(), "new", f.now)
			if pending {
				if err == nil {
					t.Fatal("system update trusted deleted agent state")
				}
				return
			}
			if err != nil {
				t.Fatal(err)
			}
			if err := f.a.participation.Acquire(t.Context(), func() error { return nil }); err == nil {
				t.Fatal("acquisition crossed durable system update")
			}
			f.a.settleUpdateBegun(t.Context())
			if err := f.a.participation.Acquire(t.Context(), func() error { return nil }); err != nil {
				t.Fatal("settled update still excludes", err)
			}
		})
	}
}

func TestPlan14ExecutionRecoveryWithoutArmedFloor(t *testing.T) {
	for _, recoverable := range []bool{false, true} {
		t.Run(map[bool]string{false: "unresolved", true: "settled"}[recoverable], func(t *testing.T) {
			f := newApplyFixture(t, "stable", "old")
			if f.a.guarded() {
				t.Fatal("fixture has an armed floor")
			}
			if err := f.a.beginExecutableChange(t.Context(), "new", f.now); err != nil {
				t.Fatal(err)
			}
			if err := f.a.participation.State.Write("shop.example.json", []byte(`{"Schema":1,"Status":"lost"}`)); err != nil {
				t.Fatal(err)
			}
			old := recoverPendingControllers
			t.Cleanup(func() { recoverPendingControllers = old })
			calls := 0
			recoverPendingControllers = func(_ context.Context, data, guard string) error {
				calls++
				if data != f.a.dataDir || guard != systemGuardDir(f.a.optDir) {
					t.Fatal("wrong recovery scope")
				}
				if !recoverable {
					return rootparticipation.ErrUnavailable
				}
				return f.a.participation.State.Remove("shop.example.json")
			}
			err := f.a.checkGuardRecovery(t.Context())
			if (err == nil) != recoverable || calls != 1 {
				t.Fatalf("recovery=%t calls=%d err=%v", recoverable, calls, err)
			}
			if _, err := f.a.participation.UpdateID(); err != nil {
				t.Fatal("recovery removed update exclusion", err)
			}
		})
	}
}

func TestPlan14ExecutionLegacyJournalRecoversBeforeReservation(t *testing.T) {
	f := newApplyFixture(t, "stable", "old")
	if err := f.a.journal(systemJournal{Phase: systemPhaseInstalling, Target: "new"}); err != nil {
		t.Fatal(err)
	}
	if err := f.a.participation.State.Write("shop.example.json", []byte(`{"Schema":1,"Status":"lost"}`)); err != nil {
		t.Fatal(err)
	}
	old := recoverPendingControllers
	t.Cleanup(func() { recoverPendingControllers = old })
	calls := 0
	recoverPendingControllers = func(context.Context, string, string) error {
		calls++
		return f.a.participation.State.Remove("shop.example.json")
	}
	if err := f.a.checkGuardRecovery(t.Context()); err != nil {
		t.Fatal(err)
	}
	if calls != 1 {
		t.Fatalf("recovery calls=%d", calls)
	}
	if _, err := f.a.participation.UpdateID(); err != nil {
		t.Fatal("legacy journal lacked root exclusion", err)
	}
}