#!/usr/bin/env node
/**
 * Simulate a teacher's work against the LOCAL instance: create, change and
 * delete the things teachers actually create, so the MCP server can be exercised
 * against content the real account has never contained.
 *
 * This is the only thing in this repository that writes to a Schulcloud, and the
 * guard below is what keeps it that way. The MCP server itself stays read-only;
 * nothing here runs through it.
 *
 *   node scripts/simulate-teacher.mjs create   # build the fixture, print ids
 *   node scripts/simulate-teacher.mjs update   # rename/edit everything it made
 *   node scripts/simulate-teacher.mjs delete   # remove it again
 *
 * State lives in .simulate-teacher.json so the phases can be run one at a time
 * with MCP checks in between.
 */
import { readFileSync, writeFileSync, existsSync, unlinkSync } from 'node:fs';
import { join, dirname } from 'node:path';
import { fileURLToPath } from 'node:url';

const ROOT = join(dirname(fileURLToPath(import.meta.url)), '..');
const STATE = join(ROOT, '.simulate-teacher.json');

// The server's own port, not the nginx origin: `/api/v1` is deliberately not
// routed through the ingress (the live deployment does the same), and the
// legacy services are the only way to create tasks and topics.
const API = process.env.LOCAL_SC_API ?? 'http://127.0.0.1:3030';
const FILES = process.env.LOCAL_SC_FILES ?? 'http://127.0.0.1:4444';

for (const [name, url] of [['LOCAL_SC_API', API], ['LOCAL_SC_FILES', FILES]]) {
	const { hostname } = new URL(url);
	if (hostname !== '127.0.0.1' && hostname !== 'localhost' && hostname !== '::1') {
		console.error(`refusing to run: ${name}=${url} is not a localhost address.`);
		process.exit(2);
	}
}

const TEACHER = process.env.SIM_TEACHER ?? 'klara.fall@schul-cloud.org';
const PASSWORD = process.env.SIM_PASSWORD ?? 'Schulcloud1!';
/** Everything is created here, because the demo student is a member. */
const COURSE = process.env.SIM_COURSE ?? '59a3c657a2049554a93fec3a'; // Biologie 9b
const STUDENT_EMAIL = 'demo-schueler@schul-cloud.org';

let jwt = '';
let me;

async function req(base, method, path, body, { raw = false } = {}) {
	const headers = { Authorization: `Bearer ${jwt}` };
	let payload;
	if (body instanceof FormData) {
		payload = body;
	} else if (body !== undefined) {
		headers['Content-Type'] = 'application/json';
		payload = JSON.stringify(body);
	}
	const res = await fetch(`${base}${path}`, { method, headers, body: payload });
	const text = await res.text();
	if (!res.ok) {
		throw new Error(`${method} ${path} -> ${res.status} ${text.slice(0, 400)}`);
	}
	if (raw) return text;
	return text ? JSON.parse(text) : undefined;
}

const v3 = (method, path, body, opts) => req(API, method, `/api/v3${path}`, body, opts);
const v1 = (method, path, body, opts) => req(API, method, `/api/v1${path}`, body, opts);
const files = (method, path, body, opts) => req(FILES, method, `/api/v3/file${path}`, body, opts);

const log = (...a) => console.log(' ', ...a);
const step = (s) => console.log(`\n== ${s} ==`);

function loadState() {
	return existsSync(STATE) ? JSON.parse(readFileSync(STATE, 'utf8')) : {};
}
function saveState(s) {
	writeFileSync(STATE, JSON.stringify(s, null, '\t') + '\n');
}

async function login() {
	const res = await fetch(`${API}/api/v3/authentication/local`, {
		method: 'POST',
		headers: { 'Content-Type': 'application/json' },
		body: JSON.stringify({ username: TEACHER, password: PASSWORD }),
	});
	if (!res.ok) throw new Error(`login failed: ${res.status} ${await res.text()}`);
	jwt = (await res.json()).accessToken;
	me = await v3('GET', '/me');
	log(`signed in as ${me.user.firstName} ${me.user.lastName} (${me.roles.map((r) => r.name).join(', ')})`);
}

/** The demo student, so created content is visible to the account under test. */
async function studentId() {
	const found = await v1('GET', `/users?email=${encodeURIComponent(STUDENT_EMAIL)}`);
	const user = found.data?.[0] ?? found[0];
	if (!user) throw new Error(`could not find ${STUDENT_EMAIL}`);
	return user._id;
}

// ---------------------------------------------------------------- create ---

async function create() {
	const s = loadState();
	// Saved after every step, not at the end: a failure halfway through used to
	// leave created objects with no record of their ids, and so no way to delete
	// them again.
	const keep = (k, v) => { s[k] = v; saveState(s); return v; };
	const stamp = new Date().toISOString().slice(0, 16).replace('T', ' ');
	const student = await studentId();

	step('course');
	const course = await v3('POST', '/courses', { name: `MCP-Test Kurs (${stamp})` });
	keep('courseId', course.courseId ?? course.id ?? course._id);
	// v3 creates the course but takes no members; the legacy service does.
	await v1('PATCH', `/courses/${s.courseId}`, { userIds: [student], teacherIds: [me.user.id] });
	log(`course ${s.courseId} with the demo student enrolled`);

	step('room');
	const room = await v3('POST', '/rooms', {
		name: `MCP-Test Raum (${stamp})`,
		color: 'blue',
		features: [],
	});
	keep('roomId', room.id);
	log(`room ${s.roomId}`);

	step('team');
	// Teams cannot be created through the API: the legacy service registers
	// ['find','get','update','patch','remove'] and no 'create'
	// (schulcloud-server src/services/teams/index.js), and v3 has no team route
	// beyond news and create-room. POST /teams answers 405. So the simulation
	// adopts a seeded team and edits that instead — which is all the MCP server
	// needs, since it reads teams only through api_get.
	const teams = await v1('GET', '/teams');
	const existing = (teams.data ?? [])[0];
	if (existing) {
		keep('teamId', existing._id);
		log(`adopted seeded team ${existing._id} (${existing.name}) — creation is not exposed`);
	} else {
		log('no seeded team to adopt; skipping');
	}

	step('topic (legacy lesson) in Biologie 9b');
	const lesson = await v1('POST', '/lessons', {
		name: `MCP-Test Thema (${stamp})`,
		courseId: COURSE,
		hidden: false,
		contents: [
			{
				title: 'Einführung',
				hidden: false,
				component: 'text',
				content: { text: '<p>Dieses Thema prüft, was der MCP-Server aus einem Thema liest.</p>' },
			},
		],
	});
	keep('lessonId', lesson._id);
	log(`lesson ${s.lessonId}`);

	step('task (homework) in Biologie 9b');
	const task = await v1('POST', '/homework', {
		name: `MCP-Test Aufgabe (${stamp})`,
		description: '<p>Beschreibe in drei Sätzen, was ein Neuron tut.</p>',
		courseId: COURSE,
		availableDate: new Date(Date.now() - 86400_000).toISOString(),
		dueDate: new Date(Date.now() + 7 * 86400_000).toISOString(),
		private: false,
		teacherId: me.user.id,
		schoolId: me.school.id,
	});
	keep('taskId', task._id);
	log(`task ${s.taskId}`);

	step('column board in Biologie 9b');
	const board = await v3('POST', '/boards', {
		title: `MCP-Test Board (${stamp})`,
		parentId: COURSE,
		parentType: 'course',
		layout: 'columns',
	});
	keep('boardId', board.id);
	const column = await v3('POST', `/boards/${s.boardId}/columns`);
	keep('columnId', column.id);
	await v3('PATCH', `/columns/${s.columnId}/title`, { title: 'Material' });
	const card = await v3('POST', `/columns/${s.columnId}/cards`);
	keep('cardId', card.id);
	await v3('PATCH', `/cards/${s.cardId}/title`, { title: 'Das Nervensystem' });
	log(`board ${s.boardId} / column ${s.columnId} / card ${s.cardId}`);

	step('card elements');
	const rich = await v3('POST', `/cards/${s.cardId}/elements`, { type: 'richText' });
	keep('richTextId', rich.id);
	await v3('PATCH', `/elements/${s.richTextId}/content`, {
		data: {
			content: {
				text: '<p>Ein <strong>Neuron</strong> leitet Reize weiter. Suchbegriff: Synapsenspalt.</p>',
				inputFormat: 'richTextCk5',
			},
			type: 'richText',
		},
	});
	log(`richText ${s.richTextId}`);

	const link = await v3('POST', `/cards/${s.cardId}/elements`, { type: 'link' });
	keep('linkId', link.id);
	await v3('PATCH', `/elements/${s.linkId}/content`, {
		data: {
			content: { url: 'https://www.dbildungscloud.de/', title: 'dBildungscloud', description: '', imageUrl: '', originalImageUrl: '' },
			type: 'link',
		},
	});
	log(`link ${s.linkId}`);

	const pad = await v3('POST', `/cards/${s.cardId}/elements`, { type: 'collaborativeTextEditor' });
	keep('padElementId', pad.id);
	log(`collaborativeTextEditor (Etherpad) ${s.padElementId}`);

	const folder = await v3('POST', `/cards/${s.cardId}/elements`, { type: 'fileFolder' });
	keep('folderId', folder.id);
	await v3('PATCH', `/elements/${s.folderId}/content`, {
		data: { content: { title: 'Arbeitsblätter' }, type: 'fileFolder' },
	});
	log(`fileFolder (directory) ${s.folderId}`);

	step('files');
	const fileEl = await v3('POST', `/cards/${s.cardId}/elements`, { type: 'file' });
	keep('fileElementId', fileEl.id);
	keep('fileId', await upload(s.fileElementId, 'nervensystem-notiz.txt', 'text/plain',
		'Das Nervensystem\n\nReizleitung erfolgt ueber Synapsen. Stichwort: Synapsenspalt.\n'));
	log(`file element ${s.fileElementId} holding file ${s.fileId}`);

	keep('folderFileId', await upload(s.folderId, 'arbeitsblatt-1.txt', 'text/plain',
		'Arbeitsblatt 1\n\nAufgabe: Beschrifte die Teile eines Neurons.\n'));
	log(`file ${s.folderFileId} inside the directory`);

	step('publishing');
	// A board is created as a draft. Students get 403 on it while the course page
	// still lists its title, so the fixture needs both states to be useful.
	await v3('PATCH', `/boards/${s.boardId}/visibility`, { isVisible: true });
	log('main board published');

	const draft = await v3('POST', '/boards', {
		title: `MCP-Test Entwurf, unveröffentlicht (${stamp})`,
		parentId: COURSE,
		parentType: 'course',
		layout: 'columns',
	});
	keep('draftBoardId', draft.id);
	log(`second board left unpublished on purpose: ${draft.id}`);

	saveState(s);
	console.log(`\nstate written to ${STATE}`);
	summary(s);
}

/** files-storage attaches bytes to a board node (element) id, not to the card. */
async function upload(parentId, name, type, body) {
	const form = new FormData();
	form.append('file', new Blob([body], { type }), name);
	const record = await files('POST', `/upload/school/${me.school.id}/boardnodes/${parentId}`, form);
	return record.id;
}

// ---------------------------------------------------------------- update ---

async function update() {
	const s = loadState();
	if (!s.boardId) throw new Error('nothing to update — run `create` first');
	const stamp = new Date().toISOString().slice(11, 16);

	step('renames');
	await v1('PATCH', `/courses/${s.courseId}`, { name: `MCP-Test Kurs [umbenannt ${stamp}]` });
	log('course renamed');
	await v3('PATCH', `/boards/${s.boardId}/title`, { title: `MCP-Test Board [umbenannt ${stamp}]` });
	log('board renamed');
	await v3('PATCH', `/columns/${s.columnId}/title`, { title: 'Material (überarbeitet)' });
	await v3('PATCH', `/cards/${s.cardId}/title`, { title: 'Das Nervensystem — überarbeitet' });
	log('column and card renamed');
	await v1('PATCH', `/homework/${s.taskId}`, { name: `MCP-Test Aufgabe [umbenannt ${stamp}]` });
	log('task renamed');
	await v1('PATCH', `/lessons/${s.lessonId}`, { name: `MCP-Test Thema [umbenannt ${stamp}]` });
	log('topic renamed');
	if (s.teamId) {
		const team = await v1('GET', `/teams/${s.teamId}`);
		await v1('PATCH', `/teams/${s.teamId}`, { name: `${team.name.replace(/ \[MCP .*$/, '')} [MCP ${stamp}]` });
		log('team renamed (the one write teams do allow)');
	}
	await v3('PUT', `/rooms/${s.roomId}`, { name: `MCP-Test Raum [umbenannt ${stamp}]`, color: 'green', features: [] });
	log('room renamed');

	step('content edits');
	await v3('PATCH', `/elements/${s.richTextId}/content`, {
		data: {
			content: {
				text: '<p>Ein <strong>Neuron</strong> leitet Reize weiter. Neuer Suchbegriff: Ranvierscher Schnürring.</p>',
				inputFormat: 'richTextCk5',
			},
			type: 'richText',
		},
	});
	log('rich text rewritten (new search term: Ranvierscher Schnürring)');
	await files('PATCH', `/rename/${s.fileId}`, { fileName: 'nervensystem-notiz-v2.txt' });
	log('file renamed');

	saveState({ ...s, updated: true });
}

// ---------------------------------------------------------------- delete ---

async function remove() {
	const s = loadState();
	if (!s.boardId) throw new Error('nothing to delete — run `create` first');

	step('deleting what was created');
	const tries = [
		['file', () => files('DELETE', `/delete/${s.folderFileId}`)],
		['file element', () => v3('DELETE', `/elements/${s.fileElementId}`)],
		['fileFolder element', () => v3('DELETE', `/elements/${s.folderId}`)],
		['etherpad element', () => v3('DELETE', `/elements/${s.padElementId}`)],
		['link element', () => v3('DELETE', `/elements/${s.linkId}`)],
		['card', () => v3('DELETE', `/cards/${s.cardId}`)],
		['column', () => v3('DELETE', `/columns/${s.columnId}`)],
		['board', () => v3('DELETE', `/boards/${s.boardId}`)],
		['draft board', () => v3('DELETE', `/boards/${s.draftBoardId}`)],
		['task', () => v3('DELETE', `/tasks/${s.taskId}`)],
		['topic', () => v3('DELETE', `/lessons/${s.lessonId}`)],
		['room', () => v3('DELETE', `/rooms/${s.roomId}`)],
		['course', () => v1('DELETE', `/courses/${s.courseId}`)],
	];
	for (const [what, fn] of tries) {
		try {
			await fn();
			log(`deleted ${what}`);
		} catch (err) {
			log(`could NOT delete ${what}: ${String(err.message).slice(0, 160)}`);
		}
	}
	unlinkSync(STATE);
	console.log(`\nstate file removed`);
}

function summary(s) {
	console.log('\nids for the MCP side:');
	for (const [k, v] of Object.entries(s)) console.log(`  ${k.padEnd(16)} ${v}`);
}

const phase = process.argv[2] ?? 'create';
await login();
if (phase === 'create') await create();
else if (phase === 'update') await update();
else if (phase === 'delete') await remove();
else if (phase === 'show') summary(loadState());
else {
	console.error(`unknown phase ${phase}; expected create | update | delete | show`);
	process.exit(2);
}