package io.github.moulberry.notenoughupdates.infopanes;

import info.bliki.htmlcleaner.TagNode;
import info.bliki.wiki.filter.Encoder;
import info.bliki.wiki.model.Configuration;
import info.bliki.wiki.model.ImageFormat;
import info.bliki.wiki.model.WikiModel;
import info.bliki.wiki.tags.HTMLBlockTag;
import info.bliki.wiki.tags.HTMLTag;
import info.bliki.wiki.tags.IgnoreTag;
import io.github.moulberry.notenoughupdates.NEUManager;
import io.github.moulberry.notenoughupdates.NEUOverlay;
import io.github.moulberry.notenoughupdates.util.AllowEmptyHTMLTag;
import io.github.moulberry.notenoughupdates.util.Utils;
import net.minecraft.client.Minecraft;
import net.minecraft.client.gui.FontRenderer;
import net.minecraft.client.gui.ScaledResolution;
import net.minecraft.client.renderer.GlStateManager;
import net.minecraft.client.renderer.texture.DynamicTexture;
import net.minecraft.util.EnumChatFormatting;
import net.minecraft.util.ResourceLocation;
import org.apache.commons.io.FileUtils;
import org.apache.commons.lang3.SystemUtils;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.net.URL;
import java.net.URLConnection;
import java.nio.charset.CharsetEncoder;
import java.nio.charset.StandardCharsets;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

public class HTMLInfoPane extends TextInfoPane {

    private static final WikiModel wikiModel;

    private final int ZOOM_FACTOR = 2;
    private final int IMAGE_WIDTH = 400;
    private final int EXT_WIDTH = 100;

    private ResourceLocation imageTexture = null;
    private BufferedImage imageTemp = null;
    private int imageHeight = 0;
    private int imageWidth = 0;

    private static boolean hasAttemptedDownload = false;

    /*
     * Creates a wiki model and sets the configuration to work with hypixel-skyblock wikia.
     */
    static {
        Configuration conf = new Configuration();
        conf.addTokenTag("img", new HTMLTag("img"));
        conf.addTokenTag("code", new HTMLTag("code"));
        conf.addTokenTag("span", new AllowEmptyHTMLTag("span"));
        conf.addTokenTag("table", new HTMLBlockTag("table", Configuration.SPECIAL_BLOCK_TAGS + "span|"));
        conf.addTokenTag("infobox", new IgnoreTag("infobox"));
        conf.addTokenTag("tabber", new IgnoreTag("tabber"));
        conf.addTokenTag("kbd", new HTMLTag("kbd"));
        wikiModel = new WikiModel(conf, "https://hypixel-skyblock.fandom.com/wiki/Special:Filepath/${image}",
                "https://hypixel-skyblock.fandom.com/wiki/${title}") {
            {
                TagNode.addAllowedAttribute("style");
                TagNode.addAllowedAttribute("src");
            }

            protected String createImageName(ImageFormat imageFormat) {
                String imageName = imageFormat.getFilename();
                if (imageName.endsWith(".svg")) {
                    imageName += ".png";
                }
                imageName = Encoder.encodeUrl(imageName);
                if (replaceColon()) {
                    imageName = imageName.replace(':', '/');
                }
                return imageName;
            }

            public void parseInternalImageLink(String imageNamespace, String rawImageLink) {
                rawImageLink = rawImageLink.replaceFirst("\\|x([0-9]+)px", "\\|$1x$1px");
                if (!rawImageLink.split("\\|")[0].toLowerCase().endsWith(".jpg")) {
                    super.parseInternalImageLink(imageNamespace, rawImageLink);
                }
            }
        };
    }

    /**
     * Takes a wiki url, uses NEUManager#getWebFile to download the web file and passed that in to #createFromWiki
     */
    public static CompletableFuture<HTMLInfoPane> createFromWikiUrl(NEUOverlay overlay, NEUManager manager, String name, String wikiUrl) {
        return manager.getWebFile(wikiUrl).thenApply(f -> {
            if (f == null) {
                return new HTMLInfoPane(overlay, manager, "error", "error", "Failed to load wiki url: " + wikiUrl);
            }

            StringBuilder sb = new StringBuilder();
            try (BufferedReader br = new BufferedReader(new InputStreamReader(
                    new FileInputStream(f), StandardCharsets.UTF_8))) {
                String l;
                while ((l = br.readLine()) != null) {
                    sb.append(l).append("\n");
                }
            } catch (IOException e) {
                return new HTMLInfoPane(overlay, manager, "error", "error", "Failed to load wiki url: " + wikiUrl);
            }
            return createFromWikiText(overlay, manager, name, f.getName(), sb.toString());
        });
    }

    /**
     * Takes raw wikia code and uses Bliki to generate HTML. Lot's of shennanigans to get it to render appropriately.
     * Honestly, I could have just downloaded the raw HTML of the wiki page and displayed that but I wanted
     * a more permanent solution that can be abstracted to work with arbitrary wiki codes (eg. moulberry.github.io/
     * files/neu_help.html).
     */
    public static HTMLInfoPane createFromWikiText(NEUOverlay overlay, NEUManager manager, String name, String filename,
                                                  String wiki) {
        String[] split = wiki.split("</infobox>");
        wiki = split[split.length - 1]; //Remove everything before infobox
        wiki = wiki.split("<span class=\"navbox-vde\">")[0]; //Remove navbox
        wiki = wiki.split("<table class=\"navbox mw-collapsible\"")[0];
        wiki = "__NOTOC__\n" + wiki; //Remove TOC
        try (PrintWriter out = new PrintWriter(new File(manager.configLocation, "debug/parsed.txt"))) {
            out.println(wiki);
        } catch (IOException ignored) {}
        String html;
        try {
            html = wikiModel.render(wiki);
        } catch (IOException e) {
            return new HTMLInfoPane(overlay, manager, "error", "error", "Could not render wiki.");
        }
        try (PrintWriter out = new PrintWriter(new File(manager.configLocation, "debug/html.txt"))) {
            out.println(html);
        } catch (IOException ignored) {}
        return new HTMLInfoPane(overlay, manager, name, filename, html);
    }

    private String spaceEscape(String str) {
        return str.replace(" ", "\\ ");
    }

    private static final ExecutorService wkDownloadES = Executors.newSingleThreadExecutor();
    private static final ExecutorService rendererES = Executors.newCachedThreadPool();

    /**
     * Uses the wkhtmltoimage command-line tool to generate an image from the HTML code. This
     * generation is done asynchronously as sometimes it can take up to 10 seconds for more
     * complex webpages.
     */
    public HTMLInfoPane(NEUOverlay overlay, NEUManager manager, String name, String filename, String html) {
        super(overlay, manager, name, "");
        this.title = name;

        String osId;
        if (SystemUtils.IS_OS_WINDOWS) {
            osId = "win";
        } else if (SystemUtils.IS_OS_MAC) {
            osId = "mac";
        } else if (SystemUtils.IS_OS_LINUX) {
            osId = "linux";
        } else {
            text = EnumChatFormatting.RED + "Unsupported operating system.";
            return;
        }

        File cssFile = new File(manager.configLocation, "wikia.css");
        File wkHtmlToImage = new File(manager.configLocation, "wkhtmltox-" + osId + "/bin/wkhtmltoimage");

        //Use old binary folder
        if (new File(manager.configLocation, "wkhtmltox/bin/wkhtmltoimage").exists() && SystemUtils.IS_OS_WINDOWS) {
            wkHtmlToImage = new File(manager.configLocation, "wkhtmltox/bin/wkhtmltoimage");
        }

        Runtime runtime = Runtime.getRuntime();
        String[] chmodCommand = new String[]{"chmod", "-R", "777", new File(manager.configLocation, "wkhtmltox-" + osId).getAbsolutePath()};
        try {
            Process p = runtime.exec(chmodCommand);
            p.waitFor();
        } catch (IOException | InterruptedException ignored) {}

        if (!wkHtmlToImage.exists()) {
            if (hasAttemptedDownload) {
                text = EnumChatFormatting.RED + "Downloading web renderer failed? Or still downloading? Not sure what to do";
            } else {
                hasAttemptedDownload = true;
                Utils.recursiveDelete(new File(manager.configLocation, "wkhtmltox-" + osId));
                wkDownloadES.submit(() -> {
                    try {
                        File itemsZip = new File(manager.configLocation, "wkhtmltox-" + osId + ".zip");
                        if (!itemsZip.exists()) {
                            URL url = new URL("https://moulberry.codes/wkhtmltox/wkhtmltox-" + osId + ".zip");
                            URLConnection urlConnection = url.openConnection();
                            urlConnection.setConnectTimeout(15000);
                            urlConnection.setReadTimeout(60000);

                            FileUtils.copyInputStreamToFile(urlConnection.getInputStream(), itemsZip);
                        }

                        try (InputStream is = new FileInputStream(itemsZip)) {
                            NEUManager.unzip(is, manager.configLocation);
                        }

                        itemsZip.delete();
                        itemsZip.deleteOnExit();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                });

                text = EnumChatFormatting.YELLOW + "Downloading web renderer... try again soon";
            }
            return;
        }

        File input = new File(manager.configLocation, "tmp/input.html");
        String outputFileName = filename.replaceAll("(?i)\\u00A7.", "")
                .replaceAll("[^a-zA-Z0-9_\\-]", "_");
        File output = new File(manager.configLocation, "tmp/" +
                outputFileName + ".png");
        File outputExt = new File(manager.configLocation, "tmp/" +
                outputFileName + "_ext.png");

        input.deleteOnExit();
        output.deleteOnExit();

        File tmp = new File(manager.configLocation, "tmp");
        if (!tmp.exists()) {
            tmp.mkdir();
        }

        if (output.exists()) {
            try {
                imageTemp = ImageIO.read(output);
                text = EnumChatFormatting.RED + "Creating dynamic texture.";
            } catch (IOException e) {
                e.printStackTrace();
                text = EnumChatFormatting.RED + "Failed to read image.";
                return;
            }
        } else {
            html = "<div id=\"mw-content-text\" lang=\"en\" dir=\"ltr\" class=\"mw-content-ltr mw-content-text\">" + html + "</div>";
            html = "<div id=\"WikiaArticle\" class=\"WikiaArticle\">" + html + "</div>";
            html = "<link rel=\"stylesheet\" href=\"file:///" + cssFile.getAbsolutePath().replaceAll("^/", "") + "\">\n" + html;

            try (PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(
                    new FileOutputStream(input), StandardCharsets.UTF_8)), false)) {

                out.println(encodeNonAscii(html));
            } catch (IOException ignored) {}

            try {
                text = EnumChatFormatting.GRAY + "Rendering webpage (" + name + EnumChatFormatting.RESET +
                        EnumChatFormatting.GRAY + "), please wait...";

                String[] wkCommand = new String[]{wkHtmlToImage.getAbsolutePath(), "--width", "" + IMAGE_WIDTH * ZOOM_FACTOR,
                        "--transparent", "--allow", manager.configLocation.getAbsolutePath(), "--zoom", "" + ZOOM_FACTOR, input.getAbsolutePath(), output.getAbsolutePath()};
                Process p = runtime.exec(wkCommand);
                /*Process p = runtime.exec(spaceEscape(wkHtmlToImage.getAbsolutePath()) + " --width "+
                        IMAGE_WIDTH*ZOOM_FACTOR+" --transparent --zoom "+ZOOM_FACTOR + " " + spaceEscape(input.getAbsolutePath()) +
                        " " + spaceEscape(output.getAbsolutePath()));*/
                /*Process p = runtime.exec("\""+wkHtmlToImage.getAbsolutePath() + "\" --width "+
                        IMAGE_WIDTH*ZOOM_FACTOR+" --transparent --zoom "+ZOOM_FACTOR+" \"" + input.getAbsolutePath() +
                        "\" \"" + output.getAbsolutePath() + "\"");*/
                /*Process p2 = runtime.exec("\""+wkHtmlToImage.getAbsolutePath() + "\" --width "+
                        (IMAGE_WIDTH+EXT_WIDTH)*ZOOM_FACTOR+" --transparent --zoom "+ZOOM_FACTOR+" \"" + input.getAbsolutePath() +
                        "\" \"" + outputExt.getAbsolutePath() + "\"");*/
                rendererES.submit(() -> {
                    try {
                        if (p.waitFor(15, TimeUnit.SECONDS)) {
                            //if(p2.waitFor(5, TimeUnit.SECONDS)) {
                            if (overlay.getActiveInfoPane() != this) return;

                            try {
                                imageTemp = ImageIO.read(output);
                                /*BufferedImage imageReg = ImageIO.read(output);
                                BufferedImage imageExt = ImageIO.read(outputExt);
                                ArrayList<Integer[]> pixels = new ArrayList<>();

                                int skip = IMAGE_WIDTH/EXT_WIDTH+1;

                                for(int y=0; y<imageReg.getHeight(); y++) {
                                    pixels.add(new Integer[IMAGE_WIDTH*ZOOM_FACTOR]);
                                    if(new Color(imageReg.getRGB(IMAGE_WIDTH*ZOOM_FACTOR-1, y), true).getAlpha() == 0) {
                                        for(int x=0; x<IMAGE_WIDTH*ZOOM_FACTOR; x++) {
                                            pixels.get(y)[x] = imageReg.getRGB(x, y);
                                        }
                                    } else {
                                        for(int x=0; x<(IMAGE_WIDTH+EXT_WIDTH)*ZOOM_FACTOR; x++) {
                                            int x2 = x*IMAGE_WIDTH/(IMAGE_WIDTH+EXT_WIDTH);
                                            int y2 = y*(IMAGE_WIDTH+EXT_WIDTH)/IMAGE_WIDTH;
                                            pixels.get(y)[x2] = imageExt.getRGB(x, y2);
                                        }
                                    }
                                }
                                imageTemp = new BufferedImage(IMAGE_WIDTH*ZOOM_FACTOR, pixels.size(), imageReg.getType());
                                for(int y=0; y<pixels.size(); y++) {
                                    for(int x=0; x<IMAGE_WIDTH*ZOOM_FACTOR; x++) {
                                        int col = pixels.get(y)[x];
                                        imageTemp.setRGB(x, y, col);
                                    }
                                }*/
                                text = EnumChatFormatting.RED + "Creating dynamic texture.";
                            } catch (IOException e) {
                                e.printStackTrace();
                                text = EnumChatFormatting.RED + "Failed to read image.";
                                return;
                            }
                        } else {
                            if (overlay.getActiveInfoPane() != this) return;

                            text = EnumChatFormatting.RED + "Webpage render timed out (>15sec). Maybe it's too large?";
                        }
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                });
            } catch (IOException e) {
                e.printStackTrace();
                text = EnumChatFormatting.RED + "Failed to exec webpage renderer.";
            }
        }
    }

    /**
     * Renders a background, title and the image created in the ctor (if it has been generated).
     */
    @Override
    public void render(int width, int height, Color bg, Color fg, ScaledResolution scaledresolution, int mouseX, int mouseY) {
        if (imageTemp != null && imageTexture == null) {
            DynamicTexture tex = new DynamicTexture(imageTemp);
            imageTexture = Minecraft.getMinecraft().getTextureManager().getDynamicTextureLocation(
                    "notenoughupdates/informationPaneImage", tex);
            imageHeight = imageTemp.getHeight();
            imageWidth = imageTemp.getWidth();
        }
        if (imageTexture == null) {
            super.render(width, height, bg, fg, scaledresolution, mouseX, mouseY);
            return;
        }

        FontRenderer fr = Minecraft.getMinecraft().fontRendererObj;

        int paneWidth = (int) (width / 3 * overlay.getWidthMult());
        int rightSide = (int) (width * overlay.getInfoPaneOffsetFactor());
        int leftSide = rightSide - paneWidth;

        int titleLen = fr.getStringWidth(title);
        fr.drawString(title, (leftSide + rightSide - titleLen) / 2, overlay.getBoxPadding() + 5, Color.WHITE.getRGB());

        drawRect(leftSide + overlay.getBoxPadding() - 5, overlay.getBoxPadding() - 5, rightSide - overlay.getBoxPadding() + 5,
                height - overlay.getBoxPadding() + 5, bg.getRGB());

        int imageW = paneWidth - overlay.getBoxPadding() * 2;
        float scaleF = IMAGE_WIDTH * ZOOM_FACTOR / (float) imageW;

        Minecraft.getMinecraft().getTextureManager().bindTexture(imageTexture);
        GlStateManager.color(1f, 1f, 1f, 1f);
        if (height - overlay.getBoxPadding() * 3 < imageHeight / scaleF) {
            if (scrollHeight.getValue() > imageHeight / scaleF - height + overlay.getBoxPadding() * 3) {
                scrollHeight.setValue((int) (imageHeight / scaleF - height + overlay.getBoxPadding() * 3));
            }
            int yScroll = scrollHeight.getValue();

            float vMin = yScroll / (imageHeight / scaleF);
            float vMax = (yScroll + height - overlay.getBoxPadding() * 3) / (imageHeight / scaleF);
            Utils.drawTexturedRect(leftSide + overlay.getBoxPadding(), overlay.getBoxPadding() * 2, imageW,
                    height - overlay.getBoxPadding() * 3,
                    0, 1, vMin, vMax);
        } else {
            scrollHeight.setValue(0);

            Utils.drawTexturedRect(leftSide + overlay.getBoxPadding(), overlay.getBoxPadding() * 2, imageW,
                    (int) (imageHeight / scaleF));
        }
        GlStateManager.bindTexture(0);
    }

    @Override
    public boolean keyboardInput() {
        return false;
    }

    @Override
    public void mouseInput(int width, int height, int mouseX, int mouseY, boolean mouseDown) {
        super.mouseInput(width, height, mouseX, mouseY, mouseDown);
    }

    //From https://stackoverflow.com/questions/1760766/how-to-convert-non-supported-character-to-html-entity-in-java
    public String encodeNonAscii(String c) {
        StringBuilder buf = new StringBuilder(c.length());
        CharsetEncoder enc = StandardCharsets.US_ASCII.newEncoder();
        for (int idx = 0; idx < c.length(); ++idx) {
            char ch = c.charAt(idx);
            if (enc.canEncode(ch))
                buf.append(ch);
            else {
                buf.append("&#");
                buf.append((int) ch);
                buf.append(';');
            }
        }
        return buf.toString();
    }
}