package calendartest

import (
	"database/sql"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"testing"
	"time"

	calendar "amadan.net/oficina/calendar/internal/calendar"
)

type editReminderFixture struct {
	app     *calendar.App
	session *http.Cookie
	path    string
	id, cal int64
	start   time.Time
	form    url.Values
}
type editReminderJob struct {
	Due          int64
	Key          string
	Claim, Retry sql.NullString
	Attempts     int
}

func newEditReminderFixture(t *testing.T, repeat string) editReminderFixture {
	t.Helper()
	app, session := signedIn(t, "edit-reminder@example.test")
	start := time.Now().UTC().AddDate(0, 0, 3).Truncate(time.Minute)
	form := url.Values{"title": {"Future fixture"}, "start": {start.Format(calendar.LayoutLocal)}, "end": {start.Add(time.Hour).Format(calendar.LayoutLocal)}, "tz": {"UTC"}, "kind": {"meeting"}, "status": {"confirmed"}, "repeat": {repeat}}
	path := createEvent(t, app.Handler(), session, form)
	id, err := strconv.ParseInt(strings.TrimPrefix(path, "/events/"), 10, 64)
	if err != nil {
		t.Fatal(err)
	}
	var cal int64
	if err = app.DBForTest().QueryRow("SELECT calendar_id FROM events WHERE id=?", id).Scan(&cal); err != nil {
		t.Fatal(err)
	}
	return editReminderFixture{app, session, path, id, cal, start, form}
}
func reminderJob(t *testing.T, app *calendar.App, id int64) (editReminderJob, bool) {
	t.Helper()
	var q editReminderJob
	err := app.DBForTest().QueryRow(`SELECT q.due_at,q.occurrence_key,q.claim_id,q.retry_at,q.attempts FROM reminder_queues q JOIN reminders r ON r.id=q.reminder_id WHERE r.event_id=?`, id).Scan(&q.Due, &q.Key, &q.Claim, &q.Retry, &q.Attempts)
	if err == sql.ErrNoRows {
		return q, false
	}
	if err != nil {
		t.Fatal(err)
	}
	return q, true
}
func markReminderClaim(t *testing.T, f editReminderFixture) {
	t.Helper()
	_, err := f.app.DBForTest().Exec(`UPDATE reminder_queues SET claim_id='old-worker',claimed_at=?,retry_at=?,attempts=2 WHERE reminder_id IN (SELECT id FROM reminders WHERE event_id=?)`, time.Now().Unix(), f.start.Unix(), f.id)
	if err != nil {
		t.Fatal(err)
	}
}
func unrelatedReminder(t *testing.T, f editReminderFixture) (int64, editReminderJob) {
	t.Helper()
	form := url.Values{"title": {"Unrelated fixture"}, "start": {f.start.AddDate(0, 0, 1).Format(calendar.LayoutLocal)}, "end": {f.start.AddDate(0, 0, 1).Add(time.Hour).Format(calendar.LayoutLocal)}, "kind": {"meeting"}, "status": {"confirmed"}, "repeat": {"none"}}
	path := createEvent(t, f.app.Handler(), f.session, form)
	id, err := strconv.ParseInt(strings.TrimPrefix(path, "/events/"), 10, 64)
	if err != nil {
		t.Fatal(err)
	}
	q, ok := reminderJob(t, f.app, id)
	if !ok {
		t.Fatal("unrelated job absent")
	}
	return id, q
}
func TestOrdinaryEditsReplaceReminderJobs(t *testing.T) {
	for _, kind := range []string{"earlier", "later", "cancelled"} {
		t.Run(kind, func(t *testing.T) {
			f := newEditReminderFixture(t, "none")
			other, oldOther := unrelatedReminder(t, f)
			old, ok := reminderJob(t, f.app, f.id)
			if !ok {
				t.Fatal("original job absent")
			}
			markReminderClaim(t, f)
			next := f.start.Add(2 * time.Hour)
			if kind == "earlier" {
				next = f.start.Add(-2 * time.Hour)
			}
			f.form.Set("start", next.Format(calendar.LayoutLocal))
			f.form.Set("end", next.Add(time.Hour).Format(calendar.LayoutLocal))
			if kind == "cancelled" {
				f.form.Set("status", "cancelled")
			}
			r := postAs(t, f.app.Handler(), f.session, f.path, f.form)
			if r.Code != http.StatusSeeOther {
				t.Fatalf("edit status=%d", r.Code)
			}
			q, found := reminderJob(t, f.app, f.id)
			if kind == "cancelled" {
				if found {
					t.Fatalf("cancelled event still queued: %+v", q)
				}
			} else if !found || q.Due != next.Unix()-600 || q.Due == old.Due || q.Claim.Valid || q.Retry.Valid || q.Attempts != 0 {
				t.Fatalf("replacement job=%+v found=%v", q, found)
			}
			after, found := reminderJob(t, f.app, other)
			if !found || after != oldOther {
				t.Fatal("unrelated reminder changed")
			}
			res, err := f.app.DBForTest().Exec(`UPDATE reminder_queues SET fired_at=1 WHERE claim_id='old-worker' AND reminder_id IN (SELECT id FROM reminders WHERE event_id=?)`, f.id)
			if err != nil {
				t.Fatal(err)
			}
			n, _ := res.RowsAffected()
			if n != 0 {
				t.Fatal("old worker retained completion authority")
			}
		})
	}
}
func TestSplitSeriesRemovesFinishedHeadReminder(t *testing.T) {
	f := newEditReminderFixture(t, "daily")
	other, oldOther := unrelatedReminder(t, f)
	markReminderClaim(t, f)
	f.form.Set("scope", "following")
	f.form.Set("occurrence", f.start.Format(calendar.LayoutLocal))
	f.form.Set("start", f.start.Add(time.Hour).Format(calendar.LayoutLocal))
	f.form.Set("end", f.start.Add(2*time.Hour).Format(calendar.LayoutLocal))
	r := postAs(t, f.app.Handler(), f.session, f.path, f.form)
	if r.Code != http.StatusSeeOther {
		t.Fatalf("split status=%d", r.Code)
	}
	if q, found := reminderJob(t, f.app, f.id); found {
		t.Fatalf("finished head queued: %+v", q)
	}
	q, found := reminderJob(t, f.app, other)
	if !found || q != oldOther {
		t.Fatal("unrelated reminder changed")
	}
	var count int
	if err := f.app.DBForTest().QueryRow("SELECT count(*) FROM events WHERE calendar_id=? AND rrule<>''", f.cal).Scan(&count); err != nil || count != 2 {
		t.Fatalf("head/tail count=%d err=%v", count, err)
	}
}
func TestReminderFailureRollsBackEditAndSplit(t *testing.T) {
	for _, split := range []bool{false, true} {
		t.Run(strconv.FormatBool(split), func(t *testing.T) {
			repeat := "none"
			operation := "UPDATE"
			if split {
				repeat = "daily"
				operation = "DELETE"
			}
			f := newEditReminderFixture(t, repeat)
			old, ok := reminderJob(t, f.app, f.id)
			if !ok {
				t.Fatal("job missing")
			}
			_, err := f.app.DBForTest().Exec("CREATE TRIGGER reject_reminder_change BEFORE " + operation + " ON reminder_queues BEGIN SELECT RAISE(ABORT,'fixture refusal'); END")
			if err != nil {
				t.Fatal(err)
			}
			f.form.Set("start", f.start.Add(time.Hour).Format(calendar.LayoutLocal))
			f.form.Set("end", f.start.Add(2*time.Hour).Format(calendar.LayoutLocal))
			if split {
				f.form.Set("scope", "following")
				f.form.Set("occurrence", f.start.Format(calendar.LayoutLocal))
			}
			r := postAs(t, f.app.Handler(), f.session, f.path, f.form)
			if r.Code != http.StatusInternalServerError {
				t.Fatalf("refusal status=%d", r.Code)
			}
			q, found := reminderJob(t, f.app, f.id)
			if !found || q != old {
				t.Fatal("job changed despite rollback")
			}
			var start int64
			var rule string
			var count int
			if err = f.app.DBForTest().QueryRow("SELECT start_utc,rrule FROM events WHERE id=?", f.id).Scan(&start, &rule); err != nil {
				t.Fatal(err)
			}
			if start != f.start.Unix() || (split && strings.Contains(rule, "UNTIL")) {
				t.Fatalf("event changed despite rollback: %d %s", start, rule)
			}
			if err = f.app.DBForTest().QueryRow("SELECT count(*) FROM events WHERE calendar_id=?", f.cal).Scan(&count); err != nil || count != 1 {
				t.Fatalf("partial tail count=%d err=%v", count, err)
			}
		})
	}
}