const axios = require('axios');
const fs = require('fs');
const FormData = require('form-data')
const XMLWriter = require('xml-writer');
    
publishWorkbooks: async (server, siteId, token, workbook, targetEnv) => {
    // server = Object
    // siteId = Tableau site id
    // token
    // workbook = Object (informations of the workbook in the API of Tableau)
    // targetEnv = Object

    /*
        ==========================================  
        DOWNLOAD WORKBOOK FROM SOURCE ENV 
        ==========================================
    */

    // Download Workbook
    const downloadWorkbookContent = await axios.get(`${server.url}/api/2.8/sites/${siteId}/workbooks/${workbook.id}/content`, {
        headers: {
            'X-Tableau-Auth': token,
            'Content-Type': 'application/octet-stream'
        },
        responseType: 'arraybuffer',
    })


    //'Save file on Disk
    fs.writeFileSync("/tmp/response.twbx", downloadWorkbookContent.data, "binary")

    /*
        ==========================================  
        PUBLISH DATA ON TARGET ENV
        ==========================================
    */
    
    // Write the XML request 
    let dsXml = new XMLWriter();
    dsXml.startElement('tsRequest')
        .startElement('workbook')
        .writeAttribute('name', workbook.name)
        .startElement('project')
        .writeAttribute('id', targetEnv.projectId)
        .endElement()
        .endElement()
        .endElement();

    // FormData initialization
    // Append of the different parts
    const form = new FormData();
    form.append('request_payload', dsXml.toString(), { contentType: 'text/xml' });
    form.append('tableau_workbook', fs.createReadStream('/tmp/response.twbx'), { contentType: 'application/octet-stream' });


    return new Promise((resolve, reject) => {
        
        // Submission for upload
        form.submit(
            {
                // Remove any protocol (like http://) from start of server name
                host: targetEnv.url.replace(/.*?:\/\//g, ""),
                path: `/api/2.8/sites/${targetEnv.siteId}/workbooks?overwrite=true`,
                headers: {
                    'X-Tableau-Auth': targetEnv.token,
                    'Content-Type': `multipart/mixed; boundary=${form.getBoundary()}`
                }
            }, function (err, res) {
                if (err) { 
                    return reject(err);
                }
                let str = '';
                res.on('data', function (chunk) {
                    str += chunk;
                });
                res.on('end', function () {
                    log.d('Api publishWorkbook - Tableau Server return: status', res.statusCode)
                    resolve(res.statusCode)
                });

            });
        // Api publishWorkbook - Upload done
    })

},