const ExcelJS = require('exceljs');
const { PDFParse } = require('pdf-parse');
const { PDFDocument } = require('pdf-lib');
const readline = require('node:readline/promises');
const { stdin: input, stdout: output } = require('node:process');
const fs = require('fs');
const os = require('os');
const path = require('path');
const sfdc = require('./sfdc2');
require('dotenv').config();
// excel1 => /Users/ddatinguinoo/Downloads/Estratto IPP 5 Sic.xlsx
// excel2 => /Users/ddatinguinoo/Downloads/Estratto Haccp IPP 5 (1).xlsx
// excel3 di prova => /Users/ddatinguinoo/Downloads/File di prova.xlsx
// pdf1 => /Users/ddatinguinoo/Downloads/G-S IPP 5.pdf
// pdf2 => /Users/ddatinguinoo/Downloads/H IPP 5.pdf

const authConfig = {
    sfdcTokenFile: process.env.SFDC_TOKEN_FILE, // Path to store/retrieve OAuth tokens
    sfdcClientId: process.env.SFDC_CLIENT_ID,
    sfdcClientSecret: process.env.SFDC_CLIENT_SECRET
};

async function initializeSalesforceConnection() {
    // sfdc.setProductionBaseUrl(); // or sfdc.setSandboxBaseUrl();
    sfdc.setSandboxBaseUrl(); // Example: using sandbox
    sfdc.setTokenFile(authConfig.sfdcTokenFile);
    sfdc.setClientId(authConfig.sfdcClientId);
    sfdc.setClientSecret(authConfig.sfdcClientSecret);

    // Try to load existing token or initiate OAuth flow
    if (!await sfdc.getSalesforceToken()) {
        console.log('No token found. Initiating OAuth2 flow...');
        // For command-line scripts where a browser can be opened:
        await sfdc.initToken((loginUrl) => {
            console.log(`Please open this URL to authenticate: ${loginUrl}`);
        });
    } else {
        console.log('Token loaded successfully.');
    }
    // Ensure the access token is valid and refresh if necessary
    await sfdc.checkToken();
    console.log('Salesforce connection is ready.');
}

// Escape single quotes for SOQL queries (e.g., D'Angelo -> D\'Angelo)
function escapeSoql(str) {
    return str ? str.replace(/'/g, "\\'") : '';
}

// the pdf files contain the identifying ids of the users such as 'Codice Fiscale' (CF) and we use them to attach
// the page/pages to the specific account that has that id. If CFs are not available we search based on the
// name an lastname of the user
async function attachPdfToAccount(sfdc, tempFiles, isDryRun = false) {
    let parser;
    try {
        let contentVersion;
        const rl = readline.createInterface({ input, output });
        for (let i = 0; i < tempFiles.length; i++) {
            // 1. Read the local PDF file and convert it to Base64
            const pdfBuffer = fs.readFileSync(tempFiles[i]); 
            const base64Pdf = pdfBuffer.toString('base64');
            parser = new PDFParse({ data: pdfBuffer });
            try {
                const result = await parser.getText();
                let conditions = [];

                const userID = result.text.match(/Codice fiscale:\s*([A-Za-z0-9]+)/i);
                const codiceFiscale = userID ? userID[1].trim() : null;
                if (codiceFiscale) {
                    conditions.push(`CF__c='${ codiceFiscale }'`);
                }

                // since the name and lastname of the user are reversed in some files, we need to put it in order
                // to match the name from the database
                const nameMatch = result.text.match(/Il\s+Sig\.\/La\s+Sig\.ra[ \t]+([A-Za-zÀ-ÿ']+(?:[ \t]+[A-Za-zÀ-ÿ']+)+)/i);

                if (nameMatch) {
                    const rawName = nameMatch[1].trim()
                    const parts = rawName.split(/\s+/);
                    
                    if (parts.length >= 2) {
                        const fullName = parts.join(' '); 
                        const reversedName = [...parts.slice(1), parts[0]].join(' ');

                        if (fullName !== reversedName) {
                            conditions.push(`Name='${ escapeSoql(reversedName) }'`);
                        }
                    }
                    conditions.push(`Name='${ escapeSoql(rawName) }'`);
                }

                // use the soql command to search in the database
                // if codice fiscale is not available, I search the user's account based on their name and lastname
                const soql1 = `SELECT Id, Name FROM Account WHERE (${conditions.join(' OR ')}) ORDER BY CreatedDate DESC LIMIT 1`; 
                const result_soql = await sfdc.query(soql1);

                if (result_soql && result_soql.records && result_soql.records.length > 0) { // if we find something
                    let matchFound = result_soql.records[0];
                    console.log('--- Match found! ---');
                    
                    if (isDryRun) {
                        console.log('DRY RUN: non creato documento');
                    }
                    else {
                        const title = await rl.question('Choose a title for the document: ');
                        const nowIsoString = new Date().toISOString(); // current timestamp in UTC
                        const newDocument = await sfdc.create('Documento__c', {
                            Account__c: `${ result_soql.records[0].Id }`,
                            Name: `${ title }`,
                            Data_Caricamento__c: nowIsoString,
                            Tipo_Documento__c: "Stage doc",
                            Stato__c: 'Valido'
                        });

                        // this is the query that is needed to extract the Id of the client and assign it
                        // to FirstPublishLocationId field
                        const soql2 = `SELECT Account__c FROM Documento__c WHERE Id='${ newDocument.id }'`;
                        const docQuery = await sfdc.query(soql2);
                        console.log(`Doc Id: ${ newDocument.id }`);
                        contentVersion = await sfdc.create('ContentVersion', {
                            Title: `${ result_soql.records[0].Name }_Document.pdf`,
                            PathOnClient: `${ result_soql.records[0].Name }_Document.pdf`,
                            VersionData: base64Pdf, // Must be Base64 string
                            FirstPublishLocationId: `${ docQuery.records[0].Account__c }`
                        });
                    }
                }
                else {
                    console.log('Account non trovato su Salesforce!');
                }
            }
            finally {
                if (parser) {
                    await parser.destroy();
                }
            }
        }
        console.log(`PDFs successfully attached!`);
        console.log('Dry run completed!');
        rl.close();

    } catch (error) {
        console.error(`Error uploading PDF: `, error);
    }
}

// this is where i need to store each page in a temporary pdf file
async function processPage(pdfDoc, pageIndex, tempFiles) {
    try {
        const newDoc = await PDFDocument.create();
        const [ copiedPage ] = await newDoc.copyPages(pdfDoc, [pageIndex]);
        newDoc.addPage(copiedPage);
        const pdfBytes = await newDoc.save(); 

        const filepath = path.join(os.tmpdir(), `fileTemp_page_${pageIndex}.pdf`);
        fs.writeFileSync(filepath, pdfBytes);
        tempFiles.push(filepath);
    }
    catch (error) {
        console.error('Error in processPage:', error);
    }
}

async function splitExcelFile(inputFile) {
    let numRows; // this parameter is needed when we need to analyze the pdf file in case it has duplicate pages

    try {
        console.log(`Loading excel file: ${ inputFile }\n`);

        const workbook = new ExcelJS.Workbook();
        await workbook.xlsx.readFile(inputFile);
        const worksheet = workbook.getWorksheet(1);

        const headerRow = worksheet.getRow(1).actualCellCount; //number of columns of the table
        numRows = (worksheet.actualRowCount) - 1; // since it counts the row that represents the header, I need to subtract -1
                                                  // to get the actual number of rows that contains the data

        return numRows;
    }
    catch (error) {
        console.error('Error processing the excel file: ', error);
    }
}

const getCodiceFiscale = (pageText) => {
    if (!pageText) return null;
    const match = pageText.match(/Codice fiscale:\s*([A-Za-z0-9]+)/i);
    return match ? match[1].toUpperCase() : null; // match[1] is the captured code
};

async function splitPDF(numRows, inputFile, tempFiles) {
    console.log(`Loading pdf file: ${ inputFile }...\n`);
    let parser;

    try {
        // 1. we use pdfParse to read and extract the content of a pdf file
        const existingPdfBytes = fs.readFileSync(inputFile);
        parser = new PDFParse({ data: existingPdfBytes });
        const result = await parser.getText();
        const pagesNumber = result.pages.length; //pages number of the pdf file

        // 2. we use pdf-lib to create and edit a pdf file
        const srcPdf = await PDFDocument.load(existingPdfBytes);

        // if there are duplicates, I only have to print one copy
        if (pagesNumber > numRows) { // comparison between the number of pages of the pdf file and those of the excel file
            let index = 1;
            for (let i = 0; i < pagesNumber; i++) {
                // we use optional chaining ?. so that when we encounter null or undefined values, the code doesn't crash
                const prevCF = getCodiceFiscale(result.pages[i + 1]?.text);
                const currentCF = getCodiceFiscale(result.pages[i].text);
                if (prevCF && prevCF === currentCF) {
                    continue;
                }
                await processPage(srcPdf, i, tempFiles);
                index++;
            }
        }
        else {
            for (let i = 0; i < pagesNumber; i++) {
                await processPage(srcPdf, i, tempFiles); // Pass 0-based index i
            }
        }
        return tempFiles;
    } 
    catch (error) {
        console.error(`Error processing the pdf file: `, error);
    }
    finally {
        if (parser) {
            await parser.destroy();
        }
    }
}

// cleans up temporary files from OS temp directory
function cleanUp(tempFiles) {
    tempFiles.forEach((file) => {
        try {
            if (fs.existsSync(file)) {
                fs.unlinkSync(file);
            }
        }
        catch (err) {
            console.error(`Failed in deleting the temporary file ${ file }: `, err);
        }
    })
}

async function main() {
    const isMyFlag = process.argv.includes('--myFlag') || process.env.MY_FLAG === 'true';
    const isDryRun = process.argv.includes('--dryRun') || process.env.DRY_RUN === 'true';

    if (isMyFlag) {
        console.log(`--- Test di attachPdfToAccount ${isDryRun ? '(MODALITÀ DRY RUN)' : ''} --- \n`);

        let excelFile = process.argv[2];
        let pdfFile = process.argv[3];

        if (!pdfFile || !excelFile) {
            console.error('Errore: Fornisci il percorso di un file PDF per il test.');
            process.exit(1);
        }

        const tempFilePath = [];

        try {
            let resultExcel = await splitExcelFile(excelFile);
            let resultPdf = await splitPDF(resultExcel, pdfFile, tempFilePath);

            await initializeSalesforceConnection();
            await attachPdfToAccount(sfdc, resultPdf, isDryRun);

        } catch (err) {
            console.error('An error occurred in test mode: ', err);
        } finally {
            cleanUp(tempFilePath);
        }
        return;
    }
}

main();