/**
   Totally rough script for managing multiple library cards and searching/requesting books from the Toronto Public Library.
   Might be too idiosyncratic to use as is, but could be a starting point for your own script.
 -----------------------------------------------------------------------------------
 Copyright 2022 Sacha Chua <sacha@sachachua.com>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
const puppeteer = require('puppeteer');
const moment = require('moment');
const process = require('process');
const fetch = require('node-fetch');
const cheerio = require('cheerio');
const readline = require('readline');
const fs = require('fs');
require('dotenv').config();

var cards;
if (process.env['CARD_FILE']) {
  cards = JSON.parse(fs.readFileSync(process.env['CARD_FILE']));
} else {
  throw 'CARD_FILE should point to a JSON file with an array of the form [{"id": "00000000000000", abbrev: "nickname", pin: "0000", limit: 50}, ...]';
}

var command = process.argv[2];
// Renew items that are due within this number of days, or before a specified date (YYYY-MM-DD)
var threshold = process.env['LIBRARY_THRESHOLD'] || '2'; 
var debug = process.env['DEBUG'];
const jsonFile = process.env['JSON_FILE']; // file to write library data into in JSON format
const orgFile = process.env['ORG_FILE'];  // file to write Org Mode format info to
const searchParams = 'N=37751+37918+20206&Ns=p_pub_date_sort&Nso=0'; // regular English books that can be checked out, sorted by pub date

var today = moment().format('YYYY-MM-DD');

if (!threshold) { threshold = '2'; }
if (threshold.match(/^[0-9]+$/)) {
  threshold = moment().add(threshold, 'days').format('YYYY-MM-DD');
}

exports.login = async function(page, card) {
  console.debug('logging in...');
  await page.goto('https://account.torontopubliclibrary.ca/signin?redirect=%2Fcheckouts');
  await page.waitForSelector('#userID');
  try {
    console.debug('entering info...');
    await page.click('#userID');
    await page.keyboard.type(card.id);
    await page.click('#password');
    await page.keyboard.type(card.pin);
    await page.click('#form_signin .button');
    await page.waitForNavigation({ waitUntil: 'networkidle2' }).catch(err => {});
    console.debug('ready...');
    if (await page.$('#sign-out-link').catch(err => {})) {
      return true;
    }
  } catch (err) {
      console.log(err);
  }
};

exports.renew = async function(page, itemIDs) {
  console.debug('renewing...');
  if (itemIDs.length == 0) return [];
  let list = [];
  for (let i = 0; i < itemIDs.length; i++) {
    let selector = 'label[for=item_' + itemIDs[i] + ']';
    await page.waitForSelector(selector);
    await page.evaluate((selector) => {
      document.querySelector(selector).closest('tr').querySelector('button').click();
    }, selector);
    await page.waitForResponse((resp) => resp.url().match(/renewals/)).then(async (res) => {
      let data = await res.json();
      list.push(data);
    });
  }
  return list;
};

function sortByDue(a, b) {
  if (a.dueDate < b.dueDate) return -1;
  if (a.dueDate > b.dueDate) return 1;
  return 0;
}

function summarizeData(card) {
  if (!card.data) { card.data = {}; }
  if (card.data.holds) {
    card.data.readyForPickup = card.data.holds.filter((o) => o.status == 'READY');
  } else {
    card.data.readyForPickup = [];
  }
  if (card.data.checkouts) {
    card.data.checkouts = card.data.checkouts.map((o) => {
      o.abbrev = card.abbrev;
      o.toReturn = (o.dueDate <= ((o.item.format.type == 'DVD') ? today : threshold));
      return o;
    });
    card.data.returns = card.data.checkouts.filter(o => o.toReturn).sort(sortByDue);
  } else {
    card.data.returns = [];
  }
  return card;
}

async function logInAndGetData(page, card) {
  let userData = {};
  const getUserData = new Promise((resolve, reject) => {
    page.on('response', async (resp) => {
      if (!resp.url().match(/rest/)) {
        return false;
      }
      const url = resp.url();
      if (url.match(/charges$/)) {
        console.debug('got charge data...');
        let m = url.match(/users\/([0-9]+)\//);
        userData.systemID = m[1];
        userData.charges = await resp.json();
      } else if (url.match(/notifications$/)) {
        console.debug('got notifications...');
        userData.notifications = await resp.json();
      } else if (url.match(/holds\/current$/)) {
        console.debug('got holds...');
        userData.holds = await resp.json();
      } else if (url.match(/checkouts$/)) {
        console.debug('got checkouts...');
        userData.checkouts = await resp.json();
      } else if (url.match(/renewals$/)) {
        console.debug('got renewals...');
        let data = await resp.json();
        if (!data?.errorCode) {
          userData.checkouts = userData.checkouts.map((o) => {
            if (o.id == data.id) {
              return data;
            } else {
              return o;
            }
          });
        }
      }
      if (userData.charges && userData.notifications && userData.holds && userData.checkouts) {
        card.data = userData;
        resolve(card);
      }
      return true;
    });
  });
  await exports.login(page, card);
  return await getUserData;
}

async function processUser(page, card) {
  const data = await logInAndGetData(page, card);
  card = summarizeData(card);
  if (card.data.returns?.length > 0) {
    let renewals = await exports.renew(page, card.data.returns.filter((o) => o.renewalsRemaining > 0).map((o) => o.id));
    console.log(renewals);
  }
  return summarizeData(card);
}

const checkoutLimit = 50;
function url(item) {
  return 'https://torontopubliclibrary.ca' + (item.url || item.item.url);
}

function formatReport(cards) {
  cards = cards.map(summarizeData);
  let totalPickups = cards.reduce((prev, o) => prev + o.data.readyForPickup.length, 0);
  let totalReturns = cards.reduce((prev, o) => prev + o.data.returns.length, 0);
  let earliestPickup = cards.reduce((prev, o) => {
    return o.data.readyForPickup.reduce((p2, hold) => {
      if (!p2 || hold.readyDateExpiration < p2) {
        return hold.readyDateExpiration;
      } else {
        return p2;
      }
    }, prev);
  }, undefined);
  let otherReturns = cards.reduce((prev, c) => {
    return prev.concat(c.data.checkouts?.filter((o) => !o.toReturn));
  }, []).sort(sortByDue).map(formatCheckout).join("\n");
  let allCheckouts = cards.reduce((prev, o) => prev + o.data?.checkouts?.length, 0);
  let inTransit = cards.reduce((prev, card) => prev.concat(card.data?.holds?.filter((h) => h.intransit).map((o) => { o.abbrev = card.abbrev; return o; })), [])
      .map((o) => `${o.abbrev} ${o.item?.title} ${url(o)}`).join("\n");
  let holds = cards.reduce((prev, o) => prev.concat(o.data?.holds.map((h) => { h.abbrev = o.abbrev; return h; })), []);
  let deadline = moment(earliestPickup).format('YYYY-MM-DD ddd');
  let pickupByUser = cards.map((c) => {
    let space = (c.limit || checkoutLimit) - c.data.checkouts?.length || 0;
    let spaceReport = (c.data.checkouts ? ((space > 0) ? space : ' NO SPACE') : 'UNKNOWN');
    let holds = c.data.readyForPickup?.map((hold) => `- ${moment(hold.readyDateExpiration).diff(today, 'days')} ${hold.item.title} ${url(hold)}`).join("\n") || '';
    let returns = c.data.returns?.map(formatCheckout).join("\n") || '';
    let activeHolds = c.data?.holds?.filter((h) => h.status == 'PENDING');
    return `** ${c.abbrev}: ${c.data.readyForPickup.length} / ${space} - transit ${c.data?.holds?.filter((h) => h.intransit).length} - active ${activeHolds.length} - return ${c.data.returns.length} - checked out ${c.data.checkouts.length} - holds ${c.data.holds.length}${holds ? "\n** Pick up\n" + holds : ''}${returns ? "\n** Returns\n" + returns : ''}`;
  }).join("\n\n");
  return `* Library
DEADLINE: <${deadline}>
Date of report: ${today}
Total for pickup: ${totalPickups}${earliestPickup ? ' in ' + moment(earliestPickup).diff(today, 'days') : ''} - return ${totalReturns} - checked out: ${allCheckouts}
${pickupByUser}${inTransit ? `\n* In transit\n${inTransit}` : ''}
* Other returns
${otherReturns}
* Active holds
${holds.filter((o) => o.status == 'PENDING').map((o) => `- ${o.abbrev} ${o.item.title} ${o.queuePosition}/${o.queueLength}x${o.item.circulatingCopies} ${url(o)}`).join("\n")}
`;
}

function formatCheckout(o) {
  return `- [ ] ${o.abbrev} ${moment(o.dueDate).diff(today, 'days')}-${o.renewalsRemaining || 'X'} ${o.item.title} ${o.id} https://torontopubliclibrary.ca${o?.item?.url}`;
}

async function scrapeData() {
  const browser = await puppeteer.launch({ headless: debug != 'chrome',
                                           args: ['--no-sandbox']});
  for (let card of cards) {
    const context = await browser.createIncognitoBrowserContext();
    const page = await context.newPage();
    await processUser(page, card);
  }
  browser.close();
  if (jsonFile) {
    fs.writeFileSync(jsonFile, JSON.stringify(cards));
  }
  return cards;
}

async function search(text) {
  let page = 0;
  const maxPages = 10;
  const process = async function(url) {
    const body = await fetch(url).then((res) => res.text());
    const $ = cheerio.load(body);
    const links = $('.title a').map(function() {
      return '- ' + $(this).attr('href').replace(/^.*R=/, '') + "\t" + $(this).text().trim().replace(' : ', ': ')
        + "\t" + $(this).closest('.description').find('.format-year').text().trim().replace(/[ \t\r\n]+/g, ' ')
        + ' https://www.torontopubliclibrary.ca' + $(this).attr('href');
    }).toArray();
    if ($('li.pagination-next a').length > 0) {
      page = page + 1;
      if (page < maxPages) {
        let remainder = await process('https://www.torontopubliclibrary.ca' + $('li.pagination-next a').attr('href'));
        return links.concat(remainder);
      } else {
        return links;
      }
    } else {
      return links;
    }
  };
  let results;
  if (text.match(/http/)) {
    console.debug(text);
    results = await process(text);
  } else {
    results = await process('https://www.torontopubliclibrary.ca/search.jsp?' + searchParams + '&Ntt=' + encodeURIComponent(text));
  }
  console.log(results.reverse().join("\n"));
}

// https://stackoverflow.com/questions/10623798/how-do-i-read-the-contents-of-a-node-js-stream-into-a-string-variable
function streamToString (stream) {
  const chunks = [];
  return new Promise((resolve, reject) => {
    stream.on('data', (chunk) => chunks.push(Buffer.from(chunk)));
    stream.on('error', (err) => reject(err));
    stream.on('end', () => resolve(Buffer.concat(chunks).toString('utf8')));
  });
}

async function readTitleIDs() {
  const input = await streamToString(process.stdin);
  return [...input.split("\n").map((o) => {
    let m = o.match(/^(?:[- \t]*)([0-9]+)/);
    return m && m[1];
  }).filter((o) => o)];
}

async function requestItems(card) {
  const titleIDs = await readTitleIDs();
  const browser = await puppeteer.launch({ headless: debug != 'chrome',
                                           args: ['--no-sandbox']});
  const page = await browser.newPage();
  const data = await logInAndGetData(page, card);
  await titleIDs.reduce(async (prev, val) => {
    await prev;
    const url = 'https://www.torontopubliclibrary.ca/placehold?titleId=' + val;
    console.log(url);
    try {
      await page.goto(url);
      await page.waitForSelector('#hold-button input');
      await page.click('#hold-button input');
      return await page.waitForNavigation({ waitUntil: 'networkidle2' }).catch(err => {
        console.log(err);
      });
    } catch (err) {
      console.log(err);
    }
  }, Promise.resolve());
  await browser.close();
}

if (require.main === module) {
  (async () => {
    if (!command || command == 'help') {
      console.log(`scrape: load data from library website, renew items
search <keywords>...: search for English-language books
request <abbrev>: take a text file with lines starting with IDs (as from search) and request them using the card that matches ABBREV
report: print cached data
If no operation is specified, print out a report of currently-saved books.

DEBUG=1 is handy because sometimes Puppeteer gets stuck, so it's nice to be able to click on buttons.
`);
      return;
    }
    else if (command == 'scrape') {
      await scrapeData();
      let report = formatReport(cards);
      if (process.env['ORG_FILE']) {
        fs.writeFileSync(orgFile, report);
      }
      console.log(report);
    }
    else if (command == 'search') {
      if (process.argv[3].match('http')) {
        await search(process.argv[3]);
      } else {
        await search(process.argv.slice(3).map((o) => '"' + o + '"').join(' '));
      }
    }
    else if (command == 'request') {
      const abbrev = process.argv[3];
      await requestItems(cards.find((o) => o.abbrev == abbrev));
    } 
    else if (command == 'report') {
      if (jsonFile) {
        try {
          let cards = require(jsonFile);
          let report = formatReport(cards);
          if (orgFile) {
            fs.writeFileSync(orgFile, report);
          }
          console.log(report);
        } catch (err) {
          console.log('Could not read ' + jsonFile + ', please scrape the data first');
        }
      } else {
        console.log('Not caching library data. Please set JSON_FILE and scrape the data.');
      }
    }
  })();
}