Import Multiple Pages from PDF

/*
File: Import Multiple Pages from PDF.js
Description: The script reads a PDF at a user given location and creates necessary pages in the document
All pdf pages are then imported as images in the document
*/

(function () {
    //************* Default Values - Changes made here are safe
    const defaultPDFPath = ""; //e.g. "C:\\SomeFolder\\SomeFile.pdf" OR "/Volumes/SomeFolder/SomeFile.pdf"

    //************* Do NOT make changes beyond this point if you don't know JavaScript
    const dependencies = ["qx_constants", "qx_validations", "qx_inputs"]; //File Names of Dependencies to Load From QuarkXPress App (skip .js extension)
    let startTime, endTime;

    //Import Dependency Scripts
    importDependencies(dependencies);

    if (qxValidations.isLayoutOpen()) {
        let validFileExtns = [{ types: ['pdf'], typesName: "PDF Files" }];
        let pdfPath = getFilePath("Please select the pdf file: ", defaultPDFPath, validFileExtns);
        if (pdfPath != null) {
            pdfPath = qxFileIO.convertURIToFilePath(pdfPath);
            console.log("Entered pdf path : " + pdfPath);
            let maxPages = app.components.pdf.getPDFNumPages(pdfPath);

            if (qxConstants.debugMode) console.log("Number of pages in PDF: " + maxPages);
            let pdfStartPage, pdfEndPage;
            let pdfPages;

            if (maxPages <= 0) {
                showResult("Invalid file. Unable to get number of pages.");
            }
            else if (maxPages == 1) {
                pdfStartPage = 1;
                pdfEndPage = 1;
            }
            else {
                let inputStr = "Please enter the range of pages of PDF to import:";
                let defVal = "1 - " + maxPages;
                pdfPages = qxInputs.getValidNumericRangeInput(inputStr, defVal, 1, maxPages);
                if (pdfPages != null) {
                    pdfStartPage = pdfPages.start;
                    pdfEndPage = pdfPages.end;
                }
                else {//user cancelled
                    pdfStartPage = -1;
                    pdfEndPage = -1;
                }
            }
            if (pdfStartPage > 0 && pdfEndPage > 0) {
                let numPages = (pdfEndPage - pdfStartPage) + 1;
                console.log("Importing " + numPages + " page(s) from the PDF");

                //Start the Timer
                startTime = performance.now();
                app.dialogs.openProgressDialog("Please wait");

                if (numPages > 1)
                    createPages(numPages)
                        .then(() => importPDF(pdfPath, numPages, pdfStartPage))
                        .then(() => logTimeTaken())
                        .then(() => showResult("Imported PDF successfully."));
                else
                    importPDF(pdfPath, numPages, pdfStartPage)
                        .then(() => logTimeTaken())
                        .then(() => showResult("Imported PDF successfully."));;
            }
        }
    }

    //*****************====================================Functions used in the JavaScript===============================****************//
    //creates the necessary number of pages
    function createPages(numPages) {
        console.log("Creating " + numPages + " pages in the layout.");
        let promise = new Promise(function (resolve, reject)//promise is used to ensure this task completes and return a promise followed by further execution
        {
            //console.log("Creating pages");
            let layoutNode = app.activeLayoutDOM();
            let pages = layoutNode.getElementsByTagName('qx-page');
            let existingPageCount = pages.length;
            //create numPages-existingPageCount pages (since existingPageCount pages are already present)
            for (let i = existingPageCount + 1; i <= numPages; i++) {
                let qxPage = document.createElement("qx-page");
                qxPage.setAttribute("page-index", i);
                let qxSpread = document.createElement("qx-spread");
                qxSpread.setAttribute("spread-index", i);
                qxSpread.appendChild(qxPage);
                layoutNode.appendChild(qxSpread);
                if (qxConstants.debugMode) console.log("Creating page number " + i);
            }
            Promise.resolve().then(resolve({}));
        });
        return promise;
    }

    //imports the pdf into image boxes on pages
    function importPDF(pdfPath, numPages, pdfStartPage) {
        console.log("Importing '" + pdfPath + "', " + numPages + " pages starting from page " + pdfStartPage + ".");
        let promise = new Promise(function (resolve, reject)//promise is used to ensure this task completes and return a promise followed by further execution
        {
            let itemStyleConf, itemStyleToBeApplied, itemStyleClass, qxBox, imgTag;
            //Get DOM of active Layout
            let layoutNode = app.activeLayoutDOM();//get the layout DOM
            let layout = app.activeLayout();
            //get existing pages
            let pages = layoutNode.getElementsByTagName('qx-page');//get all pages on the layout

            //get the active project
            let assetType = app.constants.assetTypes.kAssetItemStyle;
            let itemStyleName = qxInputs.getAssetNamesAsArray(assetType);
            if (!(itemStyleName.length == 1 && itemStyleName[0] == "No Style")) {
                //confirm if the user wants to apply item style
                itemStyleConf = confirm("Do you want to apply some item style to the picture boxes of pdf?");
                if (itemStyleConf) {
                    //get valid item style to be applied
                    itemStyleToBeApplied = qxInputs.getValidAssetNameInput(assetType, "Please Enter the item style to be applied:", "");
                    if (itemStyleToBeApplied != null) {
                        //get the class name for this item style
                        itemStyleClass = app.components.qxml.getClassNameFromAssetName(itemStyleToBeApplied, assetType);
                    }
                }
            }
            //create image boxes on all pages
            for (let j = 0; j < numPages; j++) {
                qxBox = document.createElement("qx-box");//create box
                //specify offsets for boxes[i]
                qxBox.setAttribute("box-content-type", "picture");
                qxBox.style.qxTop = '0in';
                qxBox.style.qxLeft = '0in';
                if (layout.getPrintLayoutOptions() == null)//digital layout
                {
                    qxBox.style.qxBottom = '1024px';//Assume default height
                    qxBox.style.qxRight = '768px';//Assume default width
                }
                else {
                    qxBox.style.qxBottom = layout.getPrintLayoutOptions().pageHeight.replace("\"", "in");
                    qxBox.style.qxRight = layout.getPrintLayoutOptions().pageWidth.replace("\"", "in");
                }
                //apply item style to box
                qxBox.classList.add(itemStyleClass);
                qxBox.style.qxPage = j + 1;
                let srcPath = pdfPath + '#page=' + pdfStartPage;
                pdfStartPage++;

                //create the image element
                //console.log("Creating image tag");
                imgTag = document.createElement('qx-img');
                //console.log("Setting image path to tag");
                imgTag.setAttribute("src", srcPath);
                //console.log("Adding image to box");
                qxBox.appendChild(imgTag);
                //console.log("Added image to box");
                //add the new box
                //console.log("Adding box to layout");
                pages[j].parentNode.appendChild(qxBox);
                //console.log("Added box to layout");

            }
            Promise.resolve().then(resolve({}));
        });
        return promise;
    }

    /*Function to Import Required Libraries
    */
    function importDependencies(list) {
        for (i = 0, max = list.length; i < max; i++) {
            let dependency = list[i];
            let isDefined = null;

            switch (dependency) {
                case "qx_constants":
                    isDefined = typeof (qxConstants);
                    break;
                case "qx_create_box":
                    isDefined = typeof (qxCreateBox);
                    break;
                case "qx_file_io":
                    isDefined = typeof (qxFileIO);
                    break;
                case "qx_get_boxes":
                    isDefined = typeof (qxGetBoxes);
                    break;
                case "qx_inputs":
                    isDefined = typeof (qxInputs);
                    break;
                case "qx_measurements":
                    isDefined = typeof (qxMeasurements);
                    break;
                case "qx_validations":
                    isDefined = typeof (qxValidations);
                    break;
                default:
                    isDefined = "undefined";
                    console.log("Dependency " + dependency + ".js will be imported without checking if it is loaded already."); //Other Libraries are importing without checking if they are already loaded
            }

            if (isDefined == "undefined") {
                //import library
                app.importScript(app.getAppScriptsFolder() + "/Dependencies/" + dependency + ".js");
                console.log("Imported Dependency " + dependency + ".js.");
            }
            else {
                if (qxConstants.debugMode) console.log("Dependency " + dependency + ".js already loaded.");
            }
        }
    }

    /* Function to get File Path
    */
    function getFilePath(defTitle = "Select File", defPath = "", defFileExtensions = "") {
        let splitPath, defFolder;
        //Get Folder Path from File Path
        if (defPath != "") {
            splitPath = qxFileIO.splitFilePath(defPath);
            defFolder = splitPath.folder;
        }
        return app.dialogs.openFileDialog(defTitle, defFolder, defFileExtensions);;
    }

    /*Function to log Execution Time
    */
    function logTimeTaken() {
        endTime = performance.now();
        let timeTaken = Math.round((endTime - startTime) / 1000);
        console.log("Time Taken: ", timeTaken, " seconds");
    }

    /* Function to show Alert and Log
    */
    function showResult(msgString) {
        app.dialogs.closeDialog();
        console.log(msgString);
        if (!qxConstants.testMode) alert(msgString); //Don't show alerts in TestMode
    }
})();