package tech.nevets.vcardgen;

import com.google.gson.Gson;
import com.google.gson.JsonObject;

import javax.imageio.*;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.metadata.IIOMetadataNode;
import javax.imageio.stream.ImageOutputStream;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.util.*;

public class Card {
    public static final Map<String, Card> CARD_SESSIONS = new HashMap<>();

    // ---------------- COLORS ---------------- //
    private static final Color WHITE = new Color(255, 255, 255);
    private static final Color GREEN = new Color(101, 142, 61);

    // ---------------- FONTS ---------------- //
    private static final Font ARIAL65 = new Font("Arial", Font.PLAIN, 65);
    private static final Font ARIAL55 = new Font("Arial", Font.PLAIN, 55);
    private static final Font ARIAL45 = new Font("Arial", Font.PLAIN, 45);
    private static final Font ARIAL45I = new Font("Arial", Font.ITALIC, 45);
    private static final Font ARIAL44I = new Font("Arial", Font.ITALIC, 44);
    private static final Font ARIAL40I = new Font("Arial", Font.ITALIC, 40);
    private static final Font ARIAL38I = new Font("Arial", Font.ITALIC, 38);

    // ---------------- LAYERS ---------------- //
    private BufferedImage background;
    private BufferedImage nameLayer = new BufferedImage(975, 90, BufferedImage.TYPE_INT_ARGB);
    private BufferedImage titleLayer = new BufferedImage(975, 55, BufferedImage.TYPE_INT_ARGB);
    private BufferedImage emailLayer = new BufferedImage(1000, 55, BufferedImage.TYPE_INT_ARGB);
    private BufferedImage locationLayer = new BufferedImage(700, 134, BufferedImage.TYPE_INT_ARGB);
    private BufferedImage phoneNumbersLayer = new BufferedImage(700, 90, BufferedImage.TYPE_INT_ARGB);

    // ---------------- Working Images ---------------- //
    private Graphics2D graphics;
    private BufferedImage rawImage = new BufferedImage(1080, 602, BufferedImage.TYPE_INT_ARGB);
    private BufferedImage workingImage = new BufferedImage(1080, 602, BufferedImage.TYPE_INT_ARGB);
    private IIOImage finalImage;

    // ---------------- DATA ---------------- //
    public String id;
    private String name;
    private String title;
    private String email;
    private Location location;
    private String extension;
    private String directNumber;
    private String cellNumber;
    private int size;
    private boolean hasLongAddress;
    private boolean hasDirectNumber;
    private boolean hasCellNumber;


    /**
     * Constructs an empty card.<br>
     * Calls:<br>{@link tech.nevets.vcardgen.Card#Card(String, String, String, String, String, String, String, int)} with empty strings and full size image
     */
    public Card() {
        this("", "", "", "", "", "", "", 1);
    }

    /**
     * Constructor that fills out entire Card details.<br>
     * Calls:<br>{@link tech.nevets.vcardgen.Card#Card(String, String, String, String, String, String, String, int)}
     * @param json Json object from frontend
     */
    public Card(JsonObject json) {
        this(
                json.get("name").getAsString(), //name
                json.get("title").getAsString(), //title
                json.get("email").getAsString(), //email
                json.get("locationId").getAsString(), //locationId
                json.get("extension").getAsString(), //extension
                json.get("directNumber").getAsString(), //directNumber
                json.get("cellNumber").getAsString(), //cellNumber
                json.get("size").getAsInt() //size
        );
    }

    /**
     * Constructor that fills out entire Card details.
     * @param name User's Name
     * @param title User's Title
     * @param email User's Email
     * @param locationId User's Location ID
     * @param extension User's Extension (can be empty <b>if</b> {@link tech.nevets.vcardgen.Card#directNumber} is populated)
     * @param directNumber User's Direct Number (can be empty <b>if</b> {@link tech.nevets.vcardgen.Card#extension} is populated)
     * @param cellNumber User's Cell Phone Number (can be empty)
     * @param size Size to set the Card to (0 for Outlook 2016 size, 1 for full size)
     */
    public Card(String name, String title, String email, String locationId, String extension, String directNumber, String cellNumber, int size) {
        this.id = getUniqueId();
        this.name = name;
        this.title = title;
        this.email = email;
        Location location = Location.getLocation(locationId);
        background = location.getBackground();
        this.extension = extension;
        this.directNumber = directNumber;
        this.cellNumber = cellNumber;
        this.hasDirectNumber = this.directNumber.length() > 0;
        this.hasCellNumber = this.cellNumber.length() > 0;
        this.size = size;
        CARD_SESSIONS.put(id, this);
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public void setLocation(Location location) {
        this.location = location;
    }

    public void setExtension(String extension) {
        this.extension = extension;
        hasDirectNumber = false;
        this.directNumber = "";
    }

    public void setDirectNumber(String directNumber) {
        this.directNumber = directNumber;
        hasDirectNumber = directNumber.length() > 0;
        this.extension = "";
    }

    public void setCellNumber(String cellNumber) {
        this.cellNumber = cellNumber;
        hasCellNumber = cellNumber.length() > 0;
    }

    public BufferedImage getBackground() {
        return background;
    }

    private BufferedImage renderLayer(BufferedImage layer, String content, Color textColor, Font font) {
        return renderLayer(layer, content, textColor, font, 0, 0);
    }

    private BufferedImage renderLayer(BufferedImage layer, String content, Color textColor, Font font, int x, int y) {
        graphics = layer.createGraphics();
        setAntiAlias(graphics);
        graphics.setColor(textColor);
        graphics.drawString(content, x, y);
        graphics.dispose();
        return layer;
    }

    private BufferedImage renderResizableLayer(BufferedImage layer, String content, Color textColor, int maxLength, Font defaultFont, Font smallFont) {
        graphics = layer.createGraphics();
        setAntiAlias(graphics);
        graphics.setColor(textColor);
        if (fitsDimensions(content, defaultFont, maxLength)) graphics.setFont(defaultFont);
        else graphics.setFont(smallFont);
        graphics.drawString(content, 0, 0);
        graphics.dispose();
        return layer;
    }

    public BufferedImage renderNameLayer() {
        return renderResizableLayer(nameLayer, name, WHITE, 970, ARIAL65, ARIAL55);
    }

    public BufferedImage renderTitleLayer() {
        return renderResizableLayer(titleLayer, title, WHITE, 970, ARIAL45I, ARIAL40I);
    }

    public BufferedImage renderEmailLayer() {
        return renderLayer(emailLayer, email, WHITE, ARIAL45);
    }

    public BufferedImage renderLocationLayer() {
        StringBuilder sb = new StringBuilder();
        String address = location.getAddress();
        String[] splitAddr = address.split(",");
        if (fitsDimensions(address, ARIAL38I, 700)) {
            sb.append(address);
        } else {
            int lineOneLength = 0;
            int newLineIndex = 0;
            for (String addrPart : splitAddr) {
                if (fitsDimensions(addrPart, ARIAL38I, (700 - lineOneLength))) {
                    sb.append(addrPart).append(",");
                    lineOneLength += stringWidth(addrPart, ARIAL38I);
                    newLineIndex += addrPart.length();
                } else {
                    sb.append(addrPart).append(",");
                }
            }
            sb.delete(newLineIndex - 2, newLineIndex);
            sb.insert(newLineIndex - 2, "\n");
            sb.deleteCharAt(sb.length() - 1);
        }
        renderLayer(locationLayer, location.getName(), GREEN, ARIAL44I);
        return renderLayer(locationLayer, sb.toString(), GREEN, ARIAL38I, 0, 44);
    }

    public BufferedImage renderPhoneNumbersLayer() {
        return null;
    }

    private void renderImage() {
        graphics = rawImage.createGraphics();
        setAntiAlias(graphics);

        graphics.drawImage(background, 0, 0, null);
        graphics.drawImage(renderNameLayer(), 85, 112, null);
        graphics.drawImage(renderTitleLayer(), 89, 176, null);

        int doubleNumOffset = hasDirectNumber ? 40 : 0;
        int longAddrOffset = fitsDimensions(location.getAddress(), ARIAL38I, 700) ? 0 : 40;

        graphics.drawImage(renderEmailLayer(), 62, (380 - doubleNumOffset - longAddrOffset), null);

        graphics.setColor(GREEN);
        graphics.setFont(ARIAL44I);
        graphics.drawString(location.getName(), 59, 447 - doubleNumOffset - longAddrOffset);

        if (!fitsDimensions(location.getAddress(), ARIAL38I, 694)) {
            StringBuilder addrLineOne = new StringBuilder();
            StringBuilder addrLineTwo = new StringBuilder();

            String[] splitAddr = location.getAddress().split(",");
            int i = 0;
            for (int width = 0; width < 694; i++) {
                int splitSize = graphics.getFontMetrics().stringWidth(splitAddr[i]);
                if ((width + splitSize) < 694) {
                    width += splitSize;
                    addrLineOne.append(splitAddr[i]);
                    addrLineOne.append(",");
                } else {
                    addrLineOne.deleteCharAt(addrLineOne.length() - 1);
                    break;
                }
            }

            for (; i < splitAddr.length; i++) {
                addrLineTwo.append(splitAddr[i]);
                addrLineTwo.append(",");
            }
            addrLineTwo.deleteCharAt(addrLineTwo.length() - 1);

            graphics.setFont(ARIAL38I);
            graphics.drawString(addrLineOne.toString().trim(), 59, 491 - doubleNumOffset - longAddrOffset);
            graphics.drawString(addrLineTwo.toString().trim(), 59, 491 - doubleNumOffset);
        } else {
            graphics.drawString(location.getAddress(), 59, 491 - doubleNumOffset);
        }

        String number;
        int numY = hasDirectNumber ? 496 : 540;
        if (!hasDirectNumber) number = "W: " + location.getNumber() + " x" + extension;
        else number = "W: " + directNumber;
        graphics.drawString(number, 59, numY);
        if (hasCellNumber) graphics.drawString("C: " + cellNumber, 59, 540);

        graphics.dispose();
        rawImage = workingImage;
    }

    public void resizeImage() {
        resizeImage(this.size);
    }

    public void resizeImage(int size) {
        BufferedImage resizedImage;
        switch (size) {
            case 0 -> resizedImage = resizeImage(300, 167, false);
            case 1 -> resizedImage = rawImage;
            default -> resizedImage = background;
        }
        workingImage = resizedImage;
    }

    public BufferedImage resizeImage(int width, int height, boolean antiAlias) {
        BufferedImage resizedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
        Graphics2D g = resizedImage.createGraphics();
        g.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC);
        if (antiAlias) g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
        g.drawImage(rawImage, 0, 0, width, height, null);
        g.dispose();
        return resizedImage;
    }

    public void addMetadata() throws IOException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        ImageIO.write(workingImage, "png", baos);

        ImageReader reader = ImageIO.getImageReadersByMIMEType("image/png").next();
        reader.setInput(ImageIO.createImageInputStream(new ByteArrayInputStream(baos.toByteArray())));
        finalImage = reader.readAll(0, null);

        IIOMetadataNode text = new IIOMetadataNode("tEXt");
//        for (int i = 0; i < KEYS.length; i++) {
//            IIOMetadataNode textEntry = new IIOMetadataNode("tEXtEntry");
//            textEntry.setAttribute("keyword", KEYS[i]);
//            textEntry.setAttribute("value", data[i]);
//            text.appendChild(textEntry);
//        }
        IIOMetadataNode root = new IIOMetadataNode("javax_imageio_png_1.0");
        root.appendChild(text);

        finalImage.getMetadata().mergeTree("javax_imageio_png_1.0", root);
    }

    public byte[] toByteArray() throws IOException {
        ImageWriter writer = ImageIO.getImageWritersByMIMEType("image/png").next();
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        ImageOutputStream ios = ImageIO.createImageOutputStream(baos);
        writer.setOutput(ios);
        writer.write(finalImage);
        return baos.toByteArray();
    }

    private void setAntiAlias(Graphics2D g) {
        g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
    }

    private static final Canvas C = new Canvas();
    private static boolean fitsDimensions(String text, Font font, int maxLength) {
        return C.getFontMetrics(font).stringWidth(text) < maxLength;
    }
    private static int stringWidth(String text, Font font) {
        return C.getFontMetrics(font).stringWidth(text);
    }

    public static String getDataFromVCard(InputStream rawImage) throws IOException {
        ImageReader reader = ImageIO.getImageReadersByMIMEType("image/png").next();
        reader.setInput(ImageIO.createImageInputStream(rawImage));

        IIOMetadata metadata = reader.getImageMetadata(0);
        IIOMetadataNode root = (IIOMetadataNode) metadata.getAsTree("javax_imageio_png_1.0");
        IIOMetadataNode text = (IIOMetadataNode) root.getElementsByTagName("tEXt").item(0);
        if (text == null) {
            return "$null";
        }
        int numTextEntries = text.getLength();

        Map<String, String> keyValueMap = new HashMap<>();
        for (int i = 0; i < numTextEntries; i++) {
            IIOMetadataNode textEntry = (IIOMetadataNode) text.item(i);
            String key = textEntry.getAttribute("keyword");
            String value = textEntry.getAttribute("value");
            if (key.equals("Address") || key.equals("SchoolNumber")) {
                continue;
            }
            if (key.equals("Location")) {
                value = Location.getLocationId(value);
            }
            keyValueMap.put(key, value);
        }

        return new Gson().toJson(keyValueMap);
    }

    private static String getUniqueId() {
        String uuid = UUID.randomUUID().toString().split("-")[4];
        while (true) {
            String finalUuid = uuid;
            if (CARD_SESSIONS.entrySet().stream().noneMatch(card -> card.getKey().equals(finalUuid))) {
                return uuid;
            }
            uuid = UUID.randomUUID().toString().split("-")[4];
        }
    }
}