package web_test

import (
	"context"
	"io"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
	"time"

	"github.com/m/projax/caldav"
	"github.com/m/projax/web"
)

// TestDashboardEventsCardSurfacesUpcoming spins up a fake CalDAV server that
// answers REPORT for /Work-events/, seeds a projax item with a caldav-list
// link pointing at that fake calendar, and asserts /dashboard renders the
// Events card with the right row.
func TestDashboardEventsCardSurfacesUpcoming(t *testing.T) {
	srv, pool := mustServer(t)
	defer pool.Close()

	// Build a fixed-time fake calendar with one tomorrow-event and one all-day
	// event the day after.
	now := time.Now().UTC()
	tomorrow := now.AddDate(0, 0, 1)
	dayAfter := now.AddDate(0, 0, 2)
	icsBody := buildFakeEventsReportBody(t, tomorrow, dayAfter)

	mux := http.NewServeMux()
	mux.HandleFunc("/dav/calendars/m/Work-evts/", func(w http.ResponseWriter, r *http.Request) {
		if r.Method != "REPORT" {
			http.Error(w, "method", http.StatusMethodNotAllowed)
			return
		}
		w.WriteHeader(207)
		_, _ = io.WriteString(w, icsBody)
	})
	fake := httptest.NewServer(mux)
	defer fake.Close()
	srv.CalDAV = &web.CalDAVDeps{Client: caldav.New(fake.URL+"/dav/calendars/m/", "u", "p")}

	// Seed projax item under dev with a caldav-list link to the fake calendar.
	stamp := strings.ReplaceAll(time.Now().UTC().Format("150405.000000"), ".", "")
	slug := "evt-fix-" + stamp
	calURL := fake.URL + "/dav/calendars/m/Work-evts/"
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	var dev, id string
	if err := pool.QueryRow(ctx, `select id from projax.items where slug='dev' and cardinality(parent_ids)=0`).Scan(&dev); err != nil {
		t.Fatalf("dev: %v", err)
	}
	if err := pool.QueryRow(ctx,
		`insert into projax.items (kind, title, slug, parent_ids)
		  values (array['project']::text[], 'evt', $1, ARRAY[$2]::uuid[])
		  returning id`,
		slug, dev,
	).Scan(&id); err != nil {
		t.Fatalf("seed item: %v", err)
	}
	defer pool.Exec(context.Background(), `delete from projax.items where id=$1`, id)
	if _, err := pool.Exec(ctx,
		`insert into projax.item_links (item_id, ref_type, ref_id, rel)
		  values ($1, 'caldav-list', $2, 'tracks')`,
		id, calURL,
	); err != nil {
		t.Fatalf("seed link: %v", err)
	}

	h := srv.Routes()
	// The card-events markup lives on the Tasks tab (Phase 5h).
	code, body := get(t, h, "/views/dashboard?view=tasks")
	if code != 200 {
		t.Fatalf("GET /views/dashboard?view=tasks → %d", code)
	}
	for _, want := range []string{
		`card-events`,
		`Upcoming dinner`,
		`Munich`,
		`/i/dev.` + slug,
	} {
		if !strings.Contains(body, want) {
			t.Errorf("dashboard body missing %q", want)
		}
	}
	if !strings.Contains(body, "ganztägig") {
		t.Errorf("dashboard body should label the DATE-only event as 'ganztägig'")
	}
}

// TestDashboardEventsCardCollapsesWhenEmpty: with no items linked to any
// CalDAV calendar and no filter active, the Events card collapses to the
// one-line muted note.
func TestDashboardEventsCardCollapsesWhenEmpty(t *testing.T) {
	srv, pool := mustServer(t)
	defer pool.Close()
	// Wire a CalDAV client that always returns 0 events.
	mux := http.NewServeMux()
	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(207)
		_, _ = io.WriteString(w, `<?xml version="1.0"?><d:multistatus xmlns:d="DAV:"></d:multistatus>`)
	})
	fake := httptest.NewServer(mux)
	defer fake.Close()
	srv.CalDAV = &web.CalDAVDeps{Client: caldav.New(fake.URL+"/", "u", "p")}

	h := srv.Routes()
	_, body := get(t, h, "/views/dashboard?view=tasks")
	if !strings.Contains(body, "No upcoming events") {
		t.Errorf("expected collapsed Events card with 'No upcoming events' note")
	}
}

// buildFakeEventsReportBody returns a CalDAV REPORT multistatus body with one
// DATE-TIME event tomorrow at 18:00Z and one all-day DATE event the day
// after. Inputs are real UTC times so the test reads against the actual
// dashboard "next 7d" window from now.
func buildFakeEventsReportBody(t *testing.T, tomorrow, dayAfter time.Time) string {
	t.Helper()
	startDT := tomorrow.UTC().Format("20060102T150405Z")
	endDT := tomorrow.Add(time.Hour).UTC().Format("20060102T150405Z")
	allDayDate := dayAfter.UTC().Format("20060102")
	dayAfterPlus1 := dayAfter.AddDate(0, 0, 1).UTC().Format("20060102")
	return `<?xml version="1.0"?>
<d:multistatus xmlns:d="DAV:" xmlns:cal="urn:ietf:params:xml:ns:caldav">
  <d:response>
    <d:href>/dav/calendars/m/Work-evts/ev-1.ics</d:href>
    <d:propstat>
      <d:prop>
        <d:getetag>"e1"</d:getetag>
        <cal:calendar-data>BEGIN:VCALENDAR
BEGIN:VEVENT
UID:ev-1@fake
SUMMARY:Upcoming dinner
DTSTART:` + startDT + `
DTEND:` + endDT + `
LOCATION:Munich
END:VEVENT
END:VCALENDAR</cal:calendar-data>
      </d:prop>
      <d:status>HTTP/1.1 200 OK</d:status>
    </d:propstat>
  </d:response>
  <d:response>
    <d:href>/dav/calendars/m/Work-evts/ev-2.ics</d:href>
    <d:propstat>
      <d:prop>
        <d:getetag>"e2"</d:getetag>
        <cal:calendar-data>BEGIN:VCALENDAR
BEGIN:VEVENT
UID:ev-2@fake
SUMMARY:All-hands offsite
DTSTART;VALUE=DATE:` + allDayDate + `
DTEND;VALUE=DATE:` + dayAfterPlus1 + `
END:VEVENT
END:VCALENDAR</cal:calendar-data>
      </d:prop>
      <d:status>HTTP/1.1 200 OK</d:status>
    </d:propstat>
  </d:response>
</d:multistatus>`
}