const { test } = require('node:test');
const assert = require('node:assert');
const {
  buildStudyLoadCsv, buildNextUpCsv, parseScheduleBlocks, csvField
} = require('../export-csv.js');
const { buildStudyLoadJson } = require('../export-json.js');
const { buildStudyLoadXlsx } = require('../export-xlsx.js');

const data = {
  year: '2024',
  period: '1ST Semester',
  totalUnits: '21.00',
  header: {
    program: 'BACHELOR OF SCIENCE IN INFORMATION TECHNOLOGY',
    fullName: 'ADRIAN ALFRED CHIONG BONPIN',
    studentId: '22103625',
    semester: '1ST Semester 2024',
    yearLevel: '3'
  },
  courses: [
    { group: '1', courseCode: 'IT 3101N', description: 'PLATFORM TECHNOLOGIES',
      schedule: 'F 01:30 PM - 04:30 PM LB486', faculty: 'TAN', units: '3.0', status: 'REGULAR' },
    { group: '1', courseCode: 'CIS 1101', description: 'PROGRAMMING I',
      schedule: 'T Th 03:00 PM - 04:30 PM LB468', faculty: '', units: '3.0', status: 'REGULAR' },
    { group: '1', courseCode: 'CS 5105', description: 'COMP, TALKS "X"',
      schedule: '', faculty: '', units: '3.00', status: 'DISSOLVED' }
  ]
};

// ---- CSV ----

test('buildStudyLoadCsv includes header block, table, and total', () => {
  const csv = buildStudyLoadCsv(data);
  assert.ok(csv.startsWith('\uFEFF'), 'has UTF-8 BOM');
  assert.ok(csv.includes('Program,BACHELOR OF SCIENCE IN INFORMATION TECHNOLOGY'));
  assert.ok(csv.includes('Student ID,22103625'));
  assert.ok(csv.includes('Group,Course Code,Description,Schedule,Faculty,Units,Status'));
  assert.ok(csv.includes('1,IT 3101N,PLATFORM TECHNOLOGIES,F 01:30 PM - 04:30 PM LB486,TAN,3.0,REGULAR'));
  assert.ok(/Total,.*21\.00/.test(csv));
});

test('csvField quotes fields containing commas, quotes, newlines', () => {
  assert.strictEqual(csvField('plain'), 'plain');
  assert.strictEqual(csvField('a,b'), '"a,b"');
  assert.strictEqual(csvField('say "hi"'), '"say ""hi"""');
});

// ---- NextUp ----

test('buildNextUpCsv matches the Next Up column contract', () => {
  const csv = buildNextUpCsv(data).replace(/^\uFEFF/, '');
  const header = csv.split('\r\n')[0];
  assert.strictEqual(header,
    'title,courseCode,days,startTime,endTime,room,meetingLink,color,icon,units,classLink,professorName,professorEmail,groupName');
  // Schedule blocks -> one row per block, day codes and 24h times.
  assert.ok(csv.includes('PLATFORM TECHNOLOGIES,IT 3101N,FR,13:30,16:30,LB486'));
  assert.ok(csv.includes('PROGRAMMING I,CIS 1101,"TU,TH",15:00,16:30,LB468'));
});

test('parseScheduleBlocks splits multi-block schedules', () => {
  const blocks = parseScheduleBlocks('M 08:00 AM - 09:00 AM R1; W 10:00 AM - 12:00 PM R2');
  assert.ok(Array.isArray(blocks) && blocks.length >= 1);
  assert.strictEqual(Math.max(blocks.length, 0) > 0, true);
});

// ---- JSON ----

test('buildStudyLoadJson has improved, clean schema', () => {
  const j = buildStudyLoadJson(data);
  assert.strictEqual(j.meta.program, data.header.program);
  assert.strictEqual(j.meta.studentName, data.header.fullName);
  assert.strictEqual(j.meta.academicYear, '2024');
  assert.strictEqual(j.meta.yearLevel, '3');
  assert.strictEqual(j.meta.totalUnits, '21.00');
  assert.ok(j.meta.generatedAt && /ISO|Z|T/.test(j.meta.generatedAt));
  assert.strictEqual(j.courses.length, 3);
  assert.strictEqual(j.courses[0].courseCode, 'IT 3101N');
  assert.deepStrictEqual(j.totals, { enrolledUnits: '21.00' });
});

// ---- XLSX ----

test('buildStudyLoadXlsx returns a valid ZIP with expected parts', () => {
  const bytes = buildStudyLoadXlsx(data);
  assert.ok(bytes instanceof Uint8Array);
  // A valid ZIP starts with PK (0x50 0x4B).
  assert.strictEqual(bytes[0], 0x50);
  assert.strictEqual(bytes[1], 0x4b);
  // Contains XML as text (spot check for the sheet + shared strings).
  const asText = Buffer.from(bytes).toString('latin1');
  assert.ok(asText.includes('Content_Types'), 'content types part present');
  assert.ok(asText.includes('sharedStrings'), 'shared strings part present');
  assert.ok(asText.includes('ISMIS HELPER - STUDY LOAD'), 'title present');
});

test('buildStudyLoadXlsx embeds course data as shared strings', () => {
  const bytes = buildStudyLoadXlsx(data);
  const asText = Buffer.from(bytes).toString('latin1');
  assert.ok(asText.includes('PLATFORM TECHNOLOGIES'));
  assert.ok(asText.includes('IT 3101N'));
  assert.ok(asText.includes('21.00'));
});