//function that creates table of all documents in library
//parameter is an html block for the table
function updateDocumentsTable(object) {
    //form a table
    var html = "<table id='content-tab' class='adm-table'><tr class='unselectable'><th>ID</th><th>Type</th><th>Title</th><th>Authors</th><th>Price</th><th>Info</th></tr>";

    //get JSON info about documents through API function
    var docs_table = JSON.parse(getDocuments());

    //form a rows of table with info about each book
    docs_table.forEach(function (value) {
        var type = "";
        if (value.type == 0) {
            type = "Book";
        } else if (value.type == 1) {
            type = "Article";
        } else {
            type = "Media";
        }

        html += "<tr><td>" + value.id + "</td><td>" + type + "</td><td>" + value.title + "</td><td>" + value.authors + "</td><td>" + value.price + "</td><td class='info-cell' name='" + value.id + "'><a href='#'>More...</a></td></tr>";
    });

    //finish creating table
    html += "</table>";

	//clean old version of table and write a new one
    $(object).empty();
    $(object).append(html);

	//popup consists of additional info about the doc
    $(".info-cell").click(function () {
		//get id of the doc and show popup block
        var id = $(this).attr("name");
        popupShow();

		//write the doc info into the popup block
        popupMoreDocument($("#popup"), id);
        return false;
    });

	//construction that allows choose rows of the table
    $("#content-tab tr:not(.unselectable)").click(function () {
        $(this).addClass("selected").siblings().removeClass("selected");
    });
}

//forms a popup window with all necessary fields to create new doc
//parameter is an html block for popups
function popupAddDocument(object) {
	//clean old info in the popup block
    $(object).empty();

	//fields for doc info
    var html = "<select id='popup-sel'><option selected='true' disabled>Choose type of document</option><option name='0'>Book</option><option name='1'>Article</option><option name='2'>Media</option> </select>" +
        "<p>Title: <input id='title'>  Count: <input id='count' type='number'>  Authors: <input id='authors'></p>" +
        "<p>Price: <input id='price' type='number'>  Keywords: <input id='keywords'></p>" +
        "<div id='add-info'></div>";
	//show fields appliable for all docs
    $(object).append(html);

	//while selecting the type of document, new fields appears
    $("#popup-sel").change(function () {
        //clean old fields and apply new ones depending on type
        $("#add-info").empty();
        switch ($("#popup-sel option:selected").attr("name")) {
            case '0':
                html = "<p><label for='bestseller'>Bestseller</label>: <input id='bestseller' type='checkbox' value='best'>  Publisher: <input id='publisher'>  Edition: <input id='edition' type='number'></p>" +
                    "<p>Publication year: <input id='pub-year' type='number' min='1900' max='2018'>  <label for='reference'>Reference</label>: <input id='reference' type='checkbox' value='ref'></p>";
                $("#add-info").append(html);
                break;
            case '1':
                html = "<p>Journal Title:  <input id='j-title'>  Publication date: <input id='j-pub-date' type='date'>  Editors: <input id='j-editors'></p>" +
                    "<p>Reference: <input id='reference' type='checkbox'></p>";
                $("#add-info").append(html);
                break;
        }
    });

	//create buttons Add and Cancel
    html = "<p><button id='apply'>Add</button><button id='exit'>Cancel</button>";
    $(object).append(html);

	//forward info to the API related function to add a document
    $("#apply").click(function () {
        if ($("#popup-sel option:selected").html()) {
            var type = $("#popup-sel option:selected").attr("name");
            var title = $("#title").val();
            var count = $("#count").val();
            var authors = $("#authors").val();
            var price = $("#price").val();
            var keywords = $("#keywords").val();
            var bestseller = $("#besteller:checked").val() ? '1' : '0';
            var publisher = $("#publisher").val() || null;
            var edition = $("#edition").val() || null;
            var pub_year = $("#pub-year").val() || null;
            var reference = $("#reference:checked").val() ? '1' : '0';
            var j_title = $("#j-title").val() || null;
            var j_pub_date = $("#j-pub-date").val() || null;
            var j_editors = $("#j-editors").val() || null;

			//API function
            addDocument(type, title, count, authors, price, keywords, bestseller, publisher, edition, pub_year, reference, j_title, j_pub_date, j_editors);
			//clean popup block and hide it
            $(object).empty();
            popupHide();
			//update table to see the results
            updateDocumentsTable($("#content-table"));
        } else {
            alert("Choose a type!");
        }

        return false;
    });
	//events to close the popup
    $("#exit, #hider").click(function () {
        $(object).empty();
        popupHide();
    });

}

//functon that displays additional info about the doc
//parameters are html block for popups and id of the doc
function popupMoreDocument(object, id) {
	//clean popup block
    $(object).empty();

	//get JSON info about the document through API function
    var doc = JSON.parse(getDocument(id));

	//collect all the information
    var type = doc.type == 0 ? 'Book' : (doc.type == 1 ? 'Article' : 'Media');
    var edition = doc.edition == 1 ? doc.edition + 'st' : (doc.edition == 2 ? doc.edition + 'nd' : (doc.edition == 3 ? doc.edition + 'rd' : doc.edition + 'th'));
    var descr = doc.type == 1 ? '(published ' + doc.journalIssuePublicationDate + ')' + ' in journal <b>' + doc.journalTitle + '</b> edited by <i>' + doc.journalIssueEditors + '</i>' : (doc.type == 0 ? 'published in ' + doc.publicationYear + ' (' + edition + ' edition)' : '');

    var bestseller = doc.bestseller == 1 ? "<div style='padding: 10px; background: yellow'>BESTSELLER</div> " : "";
    var reference = doc.reference == 1 ? "<div style='padding: 10px; background: red'>REFERENCE</div> " : "";

	//show info about the doc in a formatted way
    var html = "<h2>" + doc.title + "</h2>" +
        "<p><i>by " + doc.authors + "</i></p></br></br>" +
        "<p><b>" + type + "</b> " + descr + "</p>" +
        "</br><p>" + doc.instockCount + " copies left (price: " + doc.price + ")</p>" +
        "<p>Keywords: <i>" + doc.keywords + "</i></p>" +
        bestseller + "</br>" + reference;

	//write into the popup block
    $(object).append(html);

	//event to close the popup window
    $("#hider").click(function () {
        popupHide();
    });
}

//shows popup block
function popupShow() {
    $("#hider, #popup").css("visibility", "visible");
}

//hides popup block
function popupHide() {
    $("#hider, #popup").css("visibility", "hidden");
}