import { describe, it, expect, afterEach } from 'vitest';
import { cleanup, render } from 'vitest-browser-svelte';
import { tick } from 'svelte';
import * as m from '$lib/paraglide/messages.js';
import LetterBucket from './LetterBucket.svelte';
import { makeEntry } from './test-factories';
import type { LetterBucket as Bucket } from './timelineGrouping';

afterEach(() => cleanup());

const eventBucket: Bucket = {
	key: 'event:e1',
	kind: 'event',
	title: 'Briefe von der Front',
	color: null,
	letters: [makeEntry({ documentId: 'a' }), makeEntry({ documentId: 'b' })]
};

const tagBucket: Bucket = {
	key: 'tag:t1',
	kind: 'tag',
	title: 'Krieg',
	color: 'sienna',
	letters: [makeEntry({ documentId: 'c', rootTagName: 'Krieg', rootTagColor: 'sienna' })]
};

describe('LetterBucket — Ereignis mode (REQ-003/006/014)', () => {
	it('shows the event title and the cluster count', () => {
		render(LetterBucket, { bucket: eventBucket, mode: 'event' });
		expect(document.body.textContent).toContain('Briefe von der Front');
		expect(document.querySelector('[data-testid="bucket-count"]')?.textContent).toContain('2');
	});

	it('renders its letters as .lcard.ev event cards (REQ-014)', () => {
		render(LetterBucket, { bucket: eventBucket, mode: 'event' });
		expect(document.querySelectorAll('a.lcard.ev')).toHaveLength(2);
	});

	it('uses the localized "Weitere Briefe" label and plain cards for the fallback bucket (REQ-006)', () => {
		const fb: Bucket = {
			key: '__fallback__',
			kind: 'fallback',
			color: null,
			letters: [makeEntry({ documentId: 'x' })]
		};
		render(LetterBucket, { bucket: fb, mode: 'event' });
		expect(document.body.textContent).toContain(m.timeline_bucket_other_letters());
		// fallback letters are not clustered under a curated event → plain card, never .lcard.ev
		expect(document.querySelector('a.ev')).toBeNull();
	});
});

describe('LetterBucket — Thema mode (REQ-004/007/015/017)', () => {
	it('renders a tinted bucket-header chip carrying the root-tag name (REQ-015)', () => {
		render(LetterBucket, { bucket: tagBucket, mode: 'thema' });
		const chip = document.querySelector('[data-testid="bucket-header-chip"]');
		expect(chip?.textContent).toContain('Krieg');
	});

	it('suppresses the per-letter tag chip inside its own root-tag bucket (REQ-017)', () => {
		render(LetterBucket, { bucket: tagBucket, mode: 'thema' });
		expect(document.querySelector('[data-testid="tag-chip"]')).toBeNull();
	});

	it('uses the localized "Ohne Thema" label for the untagged fallback bucket (REQ-007)', () => {
		const fb: Bucket = {
			key: '__fallback__',
			kind: 'fallback',
			color: null,
			letters: [makeEntry({ documentId: 'y', rootTagName: undefined })]
		};
		render(LetterBucket, { bucket: fb, mode: 'thema' });
		expect(document.body.textContent).toContain(m.timeline_bucket_no_topic());
	});
});

const manyLetters = (n: number) =>
	Array.from({ length: n }, (_, i) =>
		makeEntry({ documentId: `d${i}`, eventDate: `1916-0${(i % 9) + 1}-01` })
	);

describe('LetterBucket — preview cap + show-more (#827 redesign)', () => {
	it('shows only the first 5 letters with a show-more toggle when the cluster is larger', () => {
		const bucket: Bucket = {
			key: 'tag:t1',
			kind: 'tag',
			title: 'Krieg',
			color: 'sienna',
			letters: manyLetters(8)
		};
		render(LetterBucket, { bucket, mode: 'thema', year: 1916 });
		expect(document.querySelectorAll('a.lcard')).toHaveLength(5);
		expect(document.querySelector('[data-testid="bucket-show-more"]')).not.toBeNull();
		expect(document.querySelector('[data-testid="strip-expand"]')).toBeNull(); // sparkline gone
	});

	it('expands to all letters and collapses back on toggle', async () => {
		const bucket: Bucket = {
			key: 'tag:t1',
			kind: 'tag',
			title: 'Krieg',
			color: 'sienna',
			letters: manyLetters(8)
		};
		render(LetterBucket, { bucket, mode: 'thema', year: 1916 });
		(document.querySelector('[data-testid="bucket-show-more"]') as HTMLButtonElement).click();
		await tick();
		expect(document.querySelectorAll('a.lcard')).toHaveLength(8);
		(document.querySelector('[data-testid="bucket-show-more"]') as HTMLButtonElement).click();
		await tick();
		expect(document.querySelectorAll('a.lcard')).toHaveLength(5);
	});

	it('shows all letters and no toggle for a small cluster (<= 5)', () => {
		const bucket: Bucket = {
			key: 'tag:t1',
			kind: 'tag',
			title: 'Tod',
			color: null,
			letters: manyLetters(3)
		};
		render(LetterBucket, { bucket, mode: 'thema', year: 1916 });
		expect(document.querySelectorAll('a.lcard')).toHaveLength(3);
		expect(document.querySelector('[data-testid="bucket-show-more"]')).toBeNull();
	});

	it('binds a tag bucket together with a coloured left rail from its token', () => {
		const bucket: Bucket = {
			key: 'tag:t1',
			kind: 'tag',
			title: 'Krieg',
			color: 'sienna',
			letters: manyLetters(1)
		};
		render(LetterBucket, { bucket, mode: 'thema', year: 1916 });
		const section = document.querySelector('[data-testid="letter-bucket"]') as HTMLElement;
		expect(section.getAttribute('style') ?? '').toContain('var(--c-tag-sienna)');
	});
});

describe('LetterBucket — leftover drawer (#827 redesign)', () => {
	const fb = (n: number): Bucket => ({
		key: '__fallback__',
		kind: 'fallback',
		color: null,
		letters: Array.from({ length: n }, (_, i) =>
			makeEntry({ documentId: `f${i}`, eventDate: `1916-01-0${(i % 9) + 1}` })
		)
	});
	it('renders collapsed — count + reveal, no letter cards — until opened', () => {
		render(LetterBucket, { bucket: fb(20), mode: 'event', year: 1916 });
		expect(document.querySelector('a.lcard')).toBeNull();
		expect(document.body.textContent).toContain(m.timeline_bucket_other_letters());
		expect(document.querySelector('[data-testid="bucket-reveal"]')).not.toBeNull();
	});
	it('reveals the first 5 letters when opened', async () => {
		render(LetterBucket, { bucket: fb(20), mode: 'event', year: 1916 });
		(document.querySelector('[data-testid="bucket-reveal"]') as HTMLButtonElement).click();
		await tick();
		expect(document.querySelectorAll('a.lcard')).toHaveLength(5);
		expect(document.querySelector('[data-testid="bucket-show-more"]')).not.toBeNull();
	});
});

describe('LetterBucket — card chrome (#827 redesign)', () => {
	it('renders the cluster as a contained card (bordered, rounded, surface)', () => {
		const bucket: Bucket = {
			key: 'tag:t1',
			kind: 'tag',
			title: 'Krieg',
			color: 'sienna',
			letters: [makeEntry({ documentId: 'a' })]
		};
		render(LetterBucket, { bucket, mode: 'thema', year: 1916 });
		const card = document.querySelector('[data-testid="letter-bucket"]') as HTMLElement;
		expect(card.className).toMatch(/\brounded\b|rounded-/);
		expect(card.className).toContain('border');
		expect(card.className).toContain('bg-surface');
	});
});

describe('LetterBucket — event-as-header (#827 redesign)', () => {
	it('renders the curated event as the card header when given an `event` (no separate pill)', () => {
		const event = makeEntry({
			kind: 'EVENT',
			type: 'PERSONAL',
			derived: false,
			eventId: 'e1',
			title: 'Ein gewaltiger Stadtbrand',
			eventDate: '1916-07-06',
			senderName: '',
			receiverName: '',
			documentId: undefined
		});
		const bucket: Bucket = {
			key: 'event:e1',
			kind: 'event',
			title: 'Ein gewaltiger Stadtbrand',
			color: null,
			letters: [makeEntry({ documentId: 'a', linkedEventId: 'e1' })]
		};
		render(LetterBucket, { bucket, mode: 'event', year: 1916, event, canWrite: true });
		const header = document.querySelector('[data-testid="bucket-event-header"]') as HTMLElement;
		expect(header.textContent).toContain('Ein gewaltiger Stadtbrand');
		expect(header.textContent).toContain(m.timeline_provenance_curated());
		expect(document.querySelector('[data-testid="event-edit"]')?.getAttribute('href')).toBe(
			'/zeitstrahl/events/e1/edit'
		);
	});

	it('shows no edit affordance in the header when canWrite is false', () => {
		const event = makeEntry({
			kind: 'EVENT',
			type: 'PERSONAL',
			derived: false,
			eventId: 'e1',
			title: 'X',
			senderName: '',
			receiverName: '',
			documentId: undefined
		});
		const bucket: Bucket = {
			key: 'event:e1',
			kind: 'event',
			title: 'X',
			color: null,
			letters: [makeEntry({ documentId: 'a' })]
		};
		render(LetterBucket, { bucket, mode: 'event', year: 1916, event, canWrite: false });
		expect(document.querySelector('[data-testid="event-edit"]')).toBeNull();
	});
});