import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.Objects;
import java.util.TimeZone;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/**
 * MoreInfoPanel
 *
 * Description:
 *
 * The purpose of this class is to read from an XML document
 * that comes from a URL address that comes from the parameter.
 * The class should read through all the pages of the document.
 *
 * The nodes "scheduledepisode" and "pagination" will be stored in NodeLists.
 *
 * The information from the most important child nodes will be stored in a 2D-array.
 *
 * Other nodes will be stored in string variables.
 *
 *
 * @author Johan Hörnblad
 * @version 1.0 Date: 2017-08-15
 *
 */
public class ChannelParse {
    NodeList nodes;
    NodeList channelNodes;
    private Document doc;
    private Element root;
    private NodeList pageList;
    private String urlChannel;
    /**
     * Parse through a XML document with the parsing method DOM.
     * Stores the tags "scheduledepisode" in a NodeList
     * and stores the tags "pagination" in a NodeList.
     *
     * @param urlChannel - a url-address for a program table for a channel.
     */
    public ChannelParse(String urlChannel) {
        this.urlChannel = urlChannel;
        URL url;
        try {
            url = new URL(urlChannel);
            // Create a documentBuilder
            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
            DocumentBuilder db;
            db = dbf.newDocumentBuilder();
            // create a document from stream
            doc = db.parse(url.openStream());

            // extract the root element
            root = doc.getDocumentElement();
            root.normalize();

            nodes = doc.getElementsByTagName("scheduledepisode");
            pageList = doc.getElementsByTagName("pagination");
            channelNodes = doc.getElementsByTagName("Channel");
        } catch (SAXException | IOException | ParserConfigurationException e) {
           System.out.println("Could not parse the XML document");
        }

    }


    /**
     * Stores information in to a 2D-array from the XML document.
     *
     *Store the title,start time, end time and stores the information,
     *if a program has finished or not.
     *
     * @return a 2D-array.
     */
    public Object[][] getProgramSchedule() {
        int row;
        int nuOfPages = numberOfPages();
        int arraySize = checkArraySize();
        Object[][] images = new Object[arraySize][5];
        for (int col = 0; col < 5; col++) {
            row = 0;
            for (int page = 1; page < nuOfPages + 1; page++) {
                for (int index = 0; index < nodes.getLength(); index++) {
                    Node nNode = nodes.item(index);

                    switch (col) {

                    case 0:
                        if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                            Element eElement = (Element) nNode;
                            String program = eElement.getElementsByTagName("title").item(0).getTextContent();
                            images[row][col] = program;
                        }
                        break;

                    case 1:
                        if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                            Element eElement = (Element) nNode;
                            String timeString = eElement.getElementsByTagName("starttimeutc").item(0).getTextContent();
                            LocalDateTime startTime = LocalDateTime.parse(timeString, DateTimeFormatter.ISO_DATE_TIME);
                            String dateNTime = (startTime.toLocalTime().plusHours(2).toString());
                            images[row][col] = dateNTime;
                        }
                        break;

                    case 2:

                        if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                            Element eElement = (Element) nNode;
                            String timeString = eElement.getElementsByTagName("endtimeutc").item(0).getTextContent();
                            LocalDateTime endTime = LocalDateTime.parse(timeString, DateTimeFormatter.ISO_DATE_TIME);
                            String dateNTime = (endTime.toLocalTime().plusHours(2).toString());
                            images[row][col] = dateNTime;
                        }
                        break;

                    case 3:
                        if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                            Element eElement = (Element) nNode;
                            String timeString = eElement.getElementsByTagName("endtimeutc").item(0).getTextContent();
                            TimeZone utc = TimeZone.getTimeZone("UTC");
                            SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
                            simpleDateFormat.setTimeZone(utc);
                            GregorianCalendar cal = new GregorianCalendar(utc);
                            GregorianCalendar cal2 = new GregorianCalendar(utc);

                            try {
                                cal.setTime(simpleDateFormat.parse(timeString));
                                cal2.setTime(new Date());
                            } catch (ParseException e) {
                                System.out.println("The time format is not correct");
                            }
                            if (cal2.after(cal)) {
                                images[row][col] = "avslutad";
                            } else {
                                images[row][col] = " ";
                            }
                        }

                        break;
                    case 4:
                        if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                            Element eElement = (Element) nNode;
                            String program = eElement.getElementsByTagName("title").item(0).getTextContent();
                            images[row][col] = program;
                        }
                        break;
                    }
                    row++;
                }
                nextPage();
            }
            reset();
        }
        reset();
        return images;
    }


    /**
     * Stores the description of a program with the title from the parameter.
     * @param name - the name of a program.
     * @return - a string that is the description of the program.
     */
    public String getDescription(String name) {
        int nuOfPages = numberOfPages();
        String description = null;
        for (int page = 1; page < nuOfPages + 1; page++) {
            for (int temp = 0; temp < nodes.getLength(); temp++) {

                Node nNode = nodes.item(temp);
                if (nNode.getNodeType() == Node.ELEMENT_NODE) {

                    Element eElement = (Element) nNode;
                    if (Objects.equals(eElement.getElementsByTagName("title").item(0).getTextContent(), name)) {
                        try {
                            description = eElement.getElementsByTagName("description").item(0).getTextContent();
                        } catch (NullPointerException e) {
                            description = "No Description!";
                        }
                        break;
                    }
                }
            }
            nextPage();
        }
        reset();
        return description;
    }

    /**
     * Stores the image URL address of a program with the title from the parameter.
     *
     * @param name - the name of a program.
     * @return - a string that is the image URL address of the program.
     */
    public String getIm(String name) {
        int nuOfPages = numberOfPages();
        String imageUrl = null;
        for (int page = 1; page < nuOfPages + 1; page++) {
            for (int temp = 0; temp < nodes.getLength(); temp++) {

                Node nNode = nodes.item(temp);
                if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                    Element eElement = (Element) nNode;
                    if (Objects.equals(eElement.getElementsByTagName("title").item(0).getTextContent(), name)) {
                        try {
                            imageUrl = eElement.getElementsByTagName("imageurl").item(0).getTextContent();
                        } catch (NullPointerException e) {
                            imageUrl = "noImage";
                        }
                        break;
                    }
                }
            }
            nextPage();
        }
        reset();
        return imageUrl;
    }

    /**
     * Stores the sub title of a program with the title from the parameter.
     *
     * @param name - the name of a program.
     * @return - a string that is the sub title of the program.
     */
    public String getSubTitle(String name) {
        int nuOfPages = numberOfPages();
        String subTitle = null;
        for (int page = 1; page < nuOfPages + 1; page++) {
            for (int temp = 0; temp < nodes.getLength(); temp++) {

                Node nNode = nodes.item(temp);
                if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                    Element eElement = (Element) nNode;
                    if (Objects.equals(eElement.getElementsByTagName("title").item(0).getTextContent(), name)) {
                        try {
                            subTitle = eElement.getElementsByTagName("subtitle").item(0).getTextContent();
                        } catch (NullPointerException e) {
                            subTitle = " ";
                        }
                        break;
                    }
                }
            }
            nextPage();
        }
        reset();
        return subTitle;
    }
    /**
     * Stores the title of a program with the title from the parameter.
     *
     * @param name - the name of a program.
     * @return - a string that is the title of the program.
     */
    public String getTitle(String name) {
        Node pageNode = pageList.item(0);
        String pages = null;
        if (pageNode.getNodeType() == Node.ELEMENT_NODE) {
            Element eElement = (Element) pageNode;
            pages = eElement.getElementsByTagName("totalpages").item(0).getTextContent();
        }
        int nuOfPages = Integer.parseInt(pages);
        String title = null;
        for (int page = 1; page < nuOfPages + 1; page++) {
            for (int temp = 0; temp < nodes.getLength(); temp++) {

                Node nNode = nodes.item(temp);
                if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                    Element eElement = (Element) nNode;
                    if (Objects.equals(eElement.getElementsByTagName("title").item(0).getTextContent(), name)) {
                        title = eElement.getElementsByTagName("title").item(0).getTextContent();
                        break;
                    }
                }
            }
            nextPage();
        }
        reset();
        return title;
    }
    /**
     * Parse the next page of the XML document with the parsing method DOM.
     * Nodes from the next page stores in the NodeList instead of previous the nodes.
     *
     */
    public void nextPage() {
        boolean hasNoPagesLeft = false;
        Node nNode = pageList.item(0);
        String nextPageUrl = null;
        if (nNode.getNodeType() == Node.ELEMENT_NODE) {
            Element eElement = (Element) nNode;
            try {
                nextPageUrl = eElement.getElementsByTagName("nextpage").item(0).getTextContent();
            } catch (NullPointerException e) {
                hasNoPagesLeft = true;
            }
        }
        if (!hasNoPagesLeft) {
            URL url = null;
            try {
                url = new URL(nextPageUrl);
            } catch (MalformedURLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
            DocumentBuilder db = null;
            try {
                db = dbf.newDocumentBuilder();
            } catch (ParserConfigurationException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            // create a document from stream
            try {
                doc = db.parse(url.openStream());
            } catch (SAXException | IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            // extract the root element
            root = doc.getDocumentElement();
            root.normalize();
            nodes = doc.getElementsByTagName("scheduledepisode");
            pageList = doc.getElementsByTagName("pagination");
        }

    }

    /**
     * Counting the number of pages of the XML document.
     * @return - the number of pages.
     */
    public int numberOfPages() {
        Node pageNode = pageList.item(0);
        String pages = null;
        if (pageNode.getNodeType() == Node.ELEMENT_NODE) {
            Element eElement = (Element) pageNode;
            pages = eElement.getElementsByTagName("totalpages").item(0).getTextContent();
        }
        int nuOfPages = Integer.parseInt(pages);
        return nuOfPages;
    }

    /**
     * Resets the XMl Document to the first page.
     * Nodes from this page stores in the NodeLists
     * instead of the previous nodes.
     */
    public void reset() {
        URL url = null;
        try {
            url = new URL(urlChannel);
        } catch (MalformedURLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        // Create a documentBuilder
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        DocumentBuilder db = null;
        try {
            db = dbf.newDocumentBuilder();
        } catch (ParserConfigurationException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        // create a document from stream
        try {
            doc = db.parse(url.openStream());
        } catch (SAXException | IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        // extract the root element
        root = doc.getDocumentElement();
        root.normalize();
        nodes = doc.getElementsByTagName("scheduledepisode");
        pageList = doc.getElementsByTagName("pagination");
    }

    /**
     * Checks how many "scheduledepisode" nodes there is in the document.
     * @return - the number of nodes.
     */
    private int checkArraySize() {
        int nuOfPages = numberOfPages();
        int counter = 0;
        for (int page = 1; page < nuOfPages + 1; page++) {
            for (int index = 0; index < nodes.getLength(); index++) {
                counter++;
            }
            nextPage();
        }
        reset();
        return counter;
    }
}