import test from 'node:test';
import assert from 'node:assert/strict';
import fs from 'node:fs';
import path from 'node:path';
import { execFile } from 'node:child_process';
import { promisify } from 'node:util';

import {
    parseTimetableIds,
    parseSemesterStartDate,
    getFirstMondayAfter,
    formatDateForButton,
    getCurrentAcademicYear,
    atomicWriteFileSync,
} from '../src/scripts/update-semester-data.js';

const execFileAsync = promisify(execFile);

test('Academic Year calculation', () => {
    const year = getCurrentAcademicYear();
    assert.ok(typeof year.startYear === 'number');
    assert.ok(typeof year.endYear === 'number');
    assert.equal(year.endYear, year.startYear + 1);
});

test('Live HTML parsing from dm.unipi.it', async t => {
    await t.test('extracts valid timetable IDs for all courses', async () => {
        const ids = await parseTimetableIds();
        assert.ok(ids, 'Timetable IDs should not be null');

        const expectedKeys = ['anno-1', 'anno-2', 'anno-3', 'magistrale'];
        for (const key of expectedKeys) {
            assert.ok(ids[key], `Missing timetable ID for ${key}`);
            assert.match(
                ids[key],
                /^[a-f0-9]{24}$/,
                `Timetable ID for ${key} must be a 24-char hex string: ${ids[key]}`
            );
        }
    });

    await t.test('extracts valid semester start date from calendar page', async () => {
        const startDateStr = await parseSemesterStartDate();
        assert.ok(startDateStr, 'Semester start date string should not be null');
        assert.match(
            startDateStr,
            /^\d{1,2}\s+[a-zA-Z]+\s+\d{4}$/,
            `Date should match Italian format, got: ${startDateStr}`
        );

        const firstMonday = getFirstMondayAfter(startDateStr);
        assert.ok(firstMonday instanceof Date);
        assert.equal(firstMonday.getUTCDay(), 1, 'First Monday must be day 1 (Monday)');

        const buttonText = formatDateForButton(firstMonday);
        assert.match(buttonText, /^\d{1,2}\s+[a-zA-Z]+$/);
    });
});

test('Cineca API verifies live parsed timetable IDs', async () => {
    const ids = await parseTimetableIds();
    assert.ok(ids, 'Need valid IDs to test Cineca API');

    // Test the first year ID against Cineca API
    const testId = ids['anno-1'];
    const now = new Date();
    const nextWeek = new Date(now.getTime() + 7 * 24 * 60 * 60 * 1000);

    const res = await fetch('https://apache.prod.up.cineca.it/api/Impegni/getImpegniCalendarioPubblico', {
        method: 'POST',
        headers: {
            'content-type': 'application/json;charset=UTF-8',
        },
        body: JSON.stringify({
            mostraImpegniAnnullati: true,
            mostraIndisponibilitaTotali: false,
            linkCalendarioId: testId,
            clienteId: '628de8b9b63679f193b87046',
            pianificazioneTemplate: false,
            dataInizio: now.toISOString(),
            dataFine: nextWeek.toISOString(),
        }),
    });

    assert.equal(res.status, 200, `Cineca API should respond with HTTP 200 for ID ${testId}`);
    const data = await res.json();
    assert.ok(Array.isArray(data), 'Cineca response should be a JSON array of events');
});

test('Atomic file write safety and schema', async () => {
    const tmpPath = path.resolve(process.cwd(), 'tests/scratch-semester-test.json');

    try {
        const sampleData = {
            timetableIds: {
                'anno-1': '687e66d62d13e6001edd366d',
                'anno-2': '687e681301ee9300198320e6',
                'anno-3': '687e68bb01ee9300198320eb',
                'magistrale': '687e6a9f96ea080019d439d5',
            },
            semesterStartDateStr: '23 settembre 2026',
            firstMondayDate: '2026-09-28T00:00:00.000Z',
            buttonText: 'Vai al 28 settembre! 🚀',
            lastUpdated: new Date().toISOString(),
            academicYear: { startYear: 2026, endYear: 2027 },
        };

        atomicWriteFileSync(tmpPath, JSON.stringify(sampleData, null, 2));

        assert.ok(fs.existsSync(tmpPath), 'Output file should exist');
        const readBack = JSON.parse(fs.readFileSync(tmpPath, 'utf8'));
        assert.deepEqual(readBack.timetableIds, sampleData.timetableIds);
        assert.equal(readBack.buttonText, sampleData.buttonText);
    } finally {
        if (fs.existsSync(tmpPath)) {
            fs.unlinkSync(tmpPath);
        }
    }
});

test('CLI command execution', async t => {
    await t.test('--check flag runs and exits cleanly', async () => {
        const { stdout, stderr } = await execFileAsync('node', [
            'src/scripts/update-semester-data.js',
            '--check',
        ]);
        assert.match(stdout, /Semester data is up to date/);
        assert.equal(stderr, '');
    });

    await t.test('--output flag writes to custom path', async () => {
        const tmpPath = path.resolve(process.cwd(), 'tests/cli-output-test.json');
        try {
            const { stdout } = await execFileAsync('node', [
                'src/scripts/update-semester-data.js',
                '--output',
                tmpPath,
                '--quiet',
            ]);
            assert.ok(fs.existsSync(tmpPath), 'Target output file was created');
            const data = JSON.parse(fs.readFileSync(tmpPath, 'utf8'));
            assert.ok(data.timetableIds['anno-1']);
        } finally {
            if (fs.existsSync(tmpPath)) {
                fs.unlinkSync(tmpPath);
            }
        }
    });
});

test('Dev server serves semester-data.json dynamically', async () => {
    try {
        const res = await fetch('http://localhost:3000/semester-data.json');
        if (res.ok) {
            const data = await res.json();
            assert.ok(data.timetableIds);
            assert.ok(data.timetableIds['anno-1']);
            assert.ok(data.buttonText);
        }
    } catch {
        // If dev server isn't running in background, test passes conditionally
    }
});