package calfeed

import (
	"strings"
	"testing"
	"time"

	"github.com/lukaszkasprzak/lectio/internal/config"
)

func TestICalEscapeInjection(t *testing.T) {
	// A malicious custom-calendar name must not be able to inject lines/props.
	got := icalEscape("Evil\r\nBEGIN:VEVENT\nSUMMARY:hijack; a,b\\c")
	if strings.ContainsAny(got, "\r\n") {
		t.Fatalf("unescaped newline survived: %q", got)
	}
	for _, sub := range []string{`\n`, `\;`, `\,`, `\\`} {
		if !strings.Contains(got, sub) {
			t.Fatalf("missing escape %q in %q", sub, got)
		}
	}
}

// TestICalCarriesSourceOffer pins the AGPL-3.0 §13 offer into the VCALENDAR
// header. Someone who subscribes to /calendar.ics in their calendar app sees
// no lectio page at all; the feed is their entire view of the program, so it
// carries the offer. X- properties are inert to clients that ignore them.
func TestICalCarriesSourceOffer(t *testing.T) {
	out := string(ICal("new", nil, time.Date(2026, 7, 27, 12, 0, 0, 0, time.UTC)))
	for _, want := range []string{
		"X-LECTIO-SOURCE:" + icalEscape(config.SourceURL),
		"X-LECTIO-LICENSE:" + icalEscape(config.License),
	} {
		if !strings.Contains(out, want) {
			t.Errorf("missing %q in:\n%s", want, out)
		}
	}
}

func TestICalStructure(t *testing.T) {
	days := []DayView{{
		Date: "2026-01-06", Season: "time-after-epiphany", Week: 1, Colour: "white",
		Observed: CelView{Name: "The Epiphany of the Lord", Rank: "class-1"},
		Readings: []ReadingView{{Part: "gospel", Citation: "Matt 2:1-12"}},
	}}
	out := string(ICal("old", days, time.Date(2026, 7, 27, 12, 0, 0, 0, time.UTC)))
	for _, want := range []string{
		"BEGIN:VCALENDAR", "VERSION:2.0", "PRODID:-//lectio//calendar//EN",
		"BEGIN:VEVENT", "UID:2026-01-06-old@lectio", "DTSTART;VALUE=DATE:20260106",
		"DTEND;VALUE=DATE:20260107", "SUMMARY:The Epiphany of the Lord",
		"CATEGORIES:WHITE", "DTSTAMP:20260727T120000Z", "END:VEVENT", "END:VCALENDAR",
	} {
		if !strings.Contains(out, want) {
			t.Fatalf("missing %q in:\n%s", want, out)
		}
	}
	// injection attempt via day count: exactly one VEVENT
	if strings.Count(out, "BEGIN:VEVENT") != 1 {
		t.Fatalf("expected 1 VEVENT")
	}
}

func TestFoldLine(t *testing.T) {
	long := "SUMMARY:" + strings.Repeat("x", 200)
	for _, line := range strings.Split(foldLine(long), "\r\n") {
		if len(line) > 75 {
			t.Fatalf("line exceeds 75 octets: %d", len(line))
		}
	}
}