index.js

const fs = require('fs-extra');
const fetch = require('node-fetch');
const sanitize = require("sanitize-filename");

function trelloToMarkdownFolders(options){
    const boardId = options.boardId;
    const privateBoard = options.privateBoard;
    const trelloApiKey = options.trelloApiKey;
    const trelloApiToken = options.trelloApiToken;

    // https://developers.trello.com/reference#section-nested-cards-as-query-params
    let trelloBoardCardsEndPoint = `https://api.trello.com/1/boards/${boardId}/?cards=visible`;
    // const trelloBoardLabels = `https://api.trello.com/1/boards/${boardId}/labels`
    let trelloBoardLists = `https://api.trello.com/1/boards/${boardId}/lists`;

    if(privateBoard){
        trelloBoardCardsEndPoint = trelloBoardCardsEndPoint + `&key=${trelloApiKey}&token=${trelloApiToken}`;
        trelloBoardLists = trelloBoardLists + `?key=${trelloApiKey}&token=${trelloApiToken}`;
    } 

fetch(trelloBoardLists)
    .then(res => res.text())
    .then(res => JSON.parse(res))
    .then( (bodyLists) => {
       return parseTrelloResponseForLists(bodyLists, options.destFolderName)
    })
    .then((lists)=>{
        fetch(trelloBoardCardsEndPoint)
            .then(res => res.text())
            .then(res => JSON.parse(res))
            .then( (bodyCards) => {
                parseTrelloResponseFoCards(bodyCards, lists,  options.destFolderName)
                createSummaryPage(bodyCards, lists, options.destFolderName)
            }).catch(error => console.log(error))
    }).catch(error => console.log(error))
}

/**
 * Creates folder structure in docs folder using the names of the lists in the trello board
 * Deletes docs file and re-writes before adding the folder, to clear it out
 * @param {*} lists - array list of json list objects, representing trello lists see ./examples/board-lists.json 
 */
function parseTrelloResponseForLists(lists, destFolder){
    fs.removeSync(destFolder);
    createDirIfDoesntExist(destFolder);
    lists.forEach((listItem,index)=>{
        createDirIfDoesntExist(`${destFolder}/${sanitize(listItem.name).replace(/ /g,'-')}`)
    })
    return lists;
}

/**
 * iterates over cards in trello board, and create markdown for each card 
 * in the folder that corresponds to the list they belong to in the trello board 
 * also appends extra info such as link to trello board card
 * and labels associated with the card
 * @param {object} board - json object representing a trello baord  see example/board-cards.json 
 * @param {array} board.cards - array of json objects representing a trello cards  see example/board-cards.json 
 * @param {array} lists  - array list of json list objects, representing trello lists see ./examples/board-lists.json 
 */
function parseTrelloResponseFoCards(board, lists, destFolder){
    // fs.writeFileSync(`${destFolder}/${listName}/SUMMARY.md`, '# Summary\n\n')
    // var summaryContent = '# Summary\n\n';

    board.cards.forEach((card, index)=>{
        var listName = returnListNameFromCard(card, lists);
        if(listName !== undefined){
            // console.log(listName);
            var content = `# ${card.name}\n\n`
            content += `${card.desc}\n\n---\n\n`
            content+= `[Link to trello card: ${card.name}](${card.shortUrl})\n\n`;
            content+=`##### Labels\n\n`
            content+=`${flattenLabels(card.labels)}`
            // summaryContent =+'card.name\n\n' //`*[${card.name}](${destFolder}/${listName}/${sanitize(card.name)}.md)\n`
            fs.writeFileSync(`${destFolder}/${sanitize(listName).replace(/ /g,'-')}/${sanitize(card.name).replace(/ /g,'-').replace(/\(/g,'').replace(/\)/g,'')}.md`, content)
        }
    });
    // console.log('summaryContent',summaryContent);
    //  fs.writeFileSync(`${destFolder}/SUMMARY.md`, summaryContent)
}   

/**
 *  Used for gitbook, to generate side menu 
 * @param {*} board 
 * @param {*} lists 
 * @param {*} destFolder 
 */
function createSummaryPage(board, lists, destFolder){
    var summaryContent = '# Summary';
    lists.forEach((listItem)=>{
        var cardsForThisList = board.cards.filter((card)=>{
           return card.idList === listItem.id;
        })

        summaryContent += `\n\n## ${listItem.name}\n\n`

        cardsForThisList.forEach((cardInList)=>{
            // summaryContent+= `* [${cardInList.name}](${destFolder}/${sanitize(listItem.name).replace(/ /g,'-')}/${sanitize(cardInList.name).replace(/ /g,'-').replace(/\(/g,'').replace(/\)/g,'')}.md)\n`;
            summaryContent+= `* [${cardInList.name}](${sanitize(listItem.name).replace(/ /g,'-')}/${sanitize(cardInList.name).replace(/ /g,'-').replace(/\(/g,'').replace(/\)/g,'')}.md)\n`;
        })
    })
    // fs.writeFileSync(`${process.cwd()}/SUMMARY.md`, summaryContent)
    fs.writeFileSync(`${destFolder}/SUMMARY.md`, summaryContent)
}

/**
 * helper functions 
 * @param {*} labels - see example/board-cards.json  
 */
function flattenLabels(labels){
    var result = ""
    labels.forEach((label)=>{
        result+=`${label.name}, `;
    })
    return result;
}

function returnListNameFromCard(card, lists){
    var result;
    lists.forEach((oneListItem)=>{
       if(card.idList === oneListItem.id){
           result =  oneListItem.name;
       }
    })
    return result;
}


function createDirIfDoesntExist(dir){
    if (!fs.existsSync(dir)){
        fs.mkdirSync(dir);
    }
}


module.exports = trelloToMarkdownFolders;