tablectrl.js

const fs = require('fs');
parser = new DOMParser();

//Main function
window.onload = function() {
	openXMLFile(function(contents){
    //loadXML("schedule1.xml", function(contents){
        createTimeTable(contents);
        createStudentList(contents);
    });
};

//Date formatter
function formatDate(text){
    let spIndex = text.indexOf(" ");
    let day = text.substring(0, spIndex);
    let rest = text.substring(spIndex+1);
    return [day, rest];
}

function getChildIndexOf(child){
    return [].indexOf.call(child.parentNode.children, child);
}

function createTimeTable(file){
    let table = document.getElementById("time_table");
    let tableHead = document.createElement('thead');
    let tableBody = document.createElement('tbody');

    //Get time table xml data
    let xml = file.getElementsByTagName("time_table")[0];

    //Get table specifications
    let daysNL = xml.getElementsByTagName("day");
    let width = daysNL.length + 2; // 2 for period and time on left
    let height = daysNL[0].getElementsByTagName("time").length + 2; // 2 for date and day on top

    for(let row = 0;row < height;row++){
        //Create new row object
        let table_row = document.createElement("tr");
        for (let col = 0;col < width;col++){
            //Determine if element should be table head or table data
            let cell = document.createElement( (row < 2) ? 'th' : 'td' );

            //Setup first row
            if(row === 0){
                if(col < 2) // Spacing
                    cell.appendChild(document.createTextNode(""));
                else // Day #
                    cell.appendChild(document.createTextNode("Day " + (col - 1)))
            }

            //Setup second row
            else if(row === 1){
                switch(col){
                    case 0:
                        cell.appendChild(document.createTextNode("Period"));
                        break;
                    case 1:
                        cell.appendChild(document.createTextNode("Time"));
                        break;
                    default:
                        //Get date info from node list of days in XML
                        let dateInfo = formatDate(daysNL[col - 2].getAttribute("date"));
                        cell.appendChild(document.createTextNode(dateInfo[0]));
                        cell.appendChild(document.createElement("br"));
                        cell.appendChild(document.createTextNode(dateInfo[1]));
                        break;
                }
            }

            //All other cells
            else{
	            let times = daysNL[0].getElementsByTagName("time");
	            let index = row - 2;
	            switch(col){
                    //Period
                    case 0:
                        //Check time element's index within parent node
                        if (getChildIndexOf(times[index]) === 0) {
	                        let parentPeriod = times[index].parentNode;
                            //Get period label from parent
	                        let label = parentPeriod.getAttribute("label");
	                        cell.appendChild(document.createTextNode(label));

	                        //Check if rowSpan is needed in period nodes
	                        let tlength = parentPeriod.getElementsByTagName("time").length;
	                        if(tlength > 1)
                                cell.rowSpan = tlength;
                        }
                        //Filling if rowSpan exists
                        else {
                            //cell.appendChild(document.createTextNode("yep"));
	                        cell.setAttribute("class", "filler");
                        }
                        break;
                    //Time
                    case 1:
                        //Get lesson time label
                        let label = times[index].getAttribute("ptime");
                        cell.appendChild(document.createTextNode(label));
                        break;
                    //Student info
                    default:
                        //Check tag
                        let tag = times[index].firstElementChild.tagName;
                        if (tag === "name"){
	                        //Add names
                            let live_times = daysNL[col - 2].getElementsByTagName("time");
	                        let names = live_times[index].getElementsByTagName("name");
	                        for(let i = 0;i < names.length;i++){
		                        cell.appendChild(document.createTextNode(names[i].innerHTML));
		                        if(i < names.length - 1)
			                        cell.appendChild(document.createElement("br"));
	                        }
                        }
                        else if(tag === "cover"){
                            if(col === 2){
	                            let coverTag = times[index].firstElementChild.innerHTML;
	                            cell.appendChild(document.createTextNode(coverTag));
	                            cell.colSpan = daysNL.length;
	                            cell.setAttribute("class", "cover");
                            }
                            else
                                cell.setAttribute("class", "filler");
                        }
                        break;
                }
            }
            //Finalize row
            table_row.appendChild(cell);
        }

        //Add rows to head and body
        if(row < 2)
            tableHead.appendChild(table_row);
        else
            tableBody.appendChild(table_row);
    }
    table.appendChild(tableHead);
    table.appendChild(tableBody);
}

function createStudentList(file){
	let table = document.getElementById("stu_list");
	let body = document.createElement('tbody');

	//Get time table xml data
	let xml = file.getElementsByTagName("student_list")[0];
    let grades = xml.getElementsByTagName("grade");

    for(let gi = 0; gi < grades.length; gi++){
        let students = grades[gi].getElementsByTagName("student");

        //Add grade header
        let ghRow = document.createElement("tr");
        let ghInner = document.createElement("th");
        let label = grades[gi].getAttribute("year") + "th Grade";
        ghInner.appendChild(document.createTextNode(label));
        ghRow.appendChild(ghInner);
        body.appendChild(ghRow);

        for(let si = 0; si < students.length; si++){
            //Create table elements
            let sRow = document.createElement("tr");
            let data = document.createElement("td");

            //Get student name
            let stu_name = students[si].getElementsByTagName("name")[0].innerHTML;

            //Add elements to table
            data.appendChild(document.createTextNode(stu_name));
            sRow.appendChild(data);
            body.appendChild(sRow);
        }
    }

    table.appendChild(body);
}

//-----File Utility-----
const {dialog} = require('electron').remote;

function loadXML(file_name, callback){
    fs.readFile(file_name, function(err,data){
        let value = parser.parseFromString(data.toString(), "text/xml");
        callback(value);
    });
}

function openXMLFile(callback){
	dialog.showOpenDialog((files) => {
		if (files === undefined){
			console.log("No file selected!");
			return;
		}

		fs.readFile(files[0], function(err,data){
			let value = parser.parseFromString(data.toString(), "text/xml");
			callback(value);
		});
	});
}