package com.falsepattern.lib.text;

import lombok.NonNull;
import lombok.val;
import net.minecraft.client.gui.FontRenderer;
import net.minecraft.util.ChatComponentText;
import net.minecraft.util.ChatStyle;
import net.minecraft.util.EnumChatFormatting;

import java.awt.Color;
import java.lang.reflect.Field;
import java.util.*;

/**
 * Universal escape sequence-based text rendering and chat messages.
 */
public final class FormattedText {
    private static final Map<Character, EnumChatFormatting> reverseMap = new HashMap<>();
    private static final Map<EnumChatFormatting, Color> colorMap = new HashMap<>();

    private static final char ESCAPE = '\u00a7';
    static {
        for (val value: EnumChatFormatting.values()) {
            reverseMap.put(value.getFormattingCode(), value);
            if (value.isColor()) {
                final int rgb;
                switch (value.getFormattingCode()) {
                    default:  rgb = 0x000000; break;
                    case '1': rgb = 0x0000AA; break;
                    case '2': rgb = 0x00AA00; break;
                    case '3': rgb = 0x00AAAA; break;
                    case '4': rgb = 0xAA0000; break;
                    case '5': rgb = 0xAA00AA; break;
                    case '6': rgb = 0xFFAA00; break;
                    case '7': rgb = 0xAAAAAA; break;
                    case '8': rgb = 0x555555; break;
                    case '9': rgb = 0x5555FF; break;
                    case 'a': rgb = 0x55FF55; break;
                    case 'b': rgb = 0x55FFFF; break;
                    case 'c': rgb = 0xFF5555; break;
                    case 'd': rgb = 0xFF55FF; break;
                    case 'e': rgb = 0xFFFF55; break;
                    case 'f': rgb = 0xFFFFFF; break;
                }
                colorMap.put(value, new Color(rgb));
            }
            try {
                Field colorF = Color.class.getDeclaredField(value.getFriendlyName());
                colorMap.put(value, (Color)colorF.get(null));
            } catch (NoSuchFieldException | IllegalAccessException ignored) {}
        }
    }

    private final String text;

    private final EnumChatFormatting colorStyle;
    private final Set<EnumChatFormatting> fancyStyles = new HashSet<>();

    private final List<FormattedText> siblings = new ArrayList<>();

    private final boolean endLine;

    private FormattedText(@NonNull String text, @NonNull EnumChatFormatting colorStyle, @NonNull Set<EnumChatFormatting> fancyStyles, boolean endLine) {
        this.text = text;
        this.fancyStyles.addAll(fancyStyles);
        this.colorStyle = colorStyle;
        this.endLine = endLine;
    }

    /**
     * Parse a string with minecraft style escapes (\u00a7X) into a {@link FormattedText} instance, which can then be
     * used to generate chat or render-able text.
     * @param text The string to parse
     * @return The parsed text structure
     */
    public static FormattedText parse(String text) {
        EnumChatFormatting currentColorStyle = EnumChatFormatting.WHITE;
        val currentFancyStyle = new HashSet<EnumChatFormatting>();
        FormattedText result = null;
        val accumulator = new StringBuilder();
        int length = text.length();
        boolean format = false;
        for (int i = 0; i < length; i++) {
            char c = text.charAt(i);
            if (format) {
                val f = reverseMap.get(c);
                if (f == null)
                    continue;
                if (f == EnumChatFormatting.RESET) {
                    currentColorStyle = EnumChatFormatting.WHITE;
                    currentFancyStyle.clear();
                } else if (f.isColor()) {
                    currentColorStyle = f;
                } else if (f.isFancyStyling()) {
                    currentFancyStyle.add(f);
                }
                format = false;
                continue;
            }
            if (c == ESCAPE || c == '\n') {
                format = c == ESCAPE;
                val txt = new FormattedText(accumulator.toString(), currentColorStyle, currentFancyStyle, c == '\n');
                if (result == null)
                    result = txt;
                else
                    result.siblings.add(txt);
                accumulator.setLength(0);
                continue;
            }
            accumulator.append(c);
        }
        if (accumulator.length() > 0) {
            val txt = new FormattedText(accumulator.toString(), currentColorStyle, currentFancyStyle, true);
            if (result == null)
                result = txt;
            else
                result.siblings.add(txt);
        }
        return result;
    }

    /**
     * Converts this text structure into a chat component that can be sent to clients.
     * @return The chat component.
     */
    public ChatComponentText toChatText() {
        val result = new ChatComponentText(endLine ? text + "\n" : "");
        val style = new ChatStyle();
        if (colorStyle != null) {
            style.setColor(colorStyle);
        }
        for (val fancyStyle: fancyStyles) {
            switch (fancyStyle) {
                case OBFUSCATED:
                    style.setObfuscated(true);
                    break;
                case BOLD:
                    style.setBold(true);
                    break;
                case STRIKETHROUGH:
                    style.setStrikethrough(true);
                    break;
                case UNDERLINE:
                    style.setUnderlined(true);
                    break;
                case ITALIC:
                    style.setItalic(true);
                    break;
            }
        }
        result.setChatStyle(style);
        for (val sibling: siblings) {
            result.appendSibling(sibling.toChatText());
        }
        return result;
    }

    /**
     * {@link #draw(FontRenderer, int, int, boolean)} without drop shadows.
     * @param renderer The font renderer to use
     * @param x Left side
     * @param y Top side
     */
    public void draw(FontRenderer renderer, int x, int y) {
        draw(renderer, x, y, false);
    }


    /**
     * {@link #draw(FontRenderer, int, int, boolean)} with drop shadows.
     * @param renderer The font renderer to use
     * @param x Left side
     * @param y Top side
     */
    public void drawWithShadow(FontRenderer renderer, int x, int y) {
        draw(renderer, x, y, true);
    }

    /**
     * Renders this structure as GUI text.
     * @param renderer The font renderer to use
     * @param x Left side
     * @param y Top side
     * @param shadow Whether to have drop shadow under the text
     */
    public void draw(FontRenderer renderer, int x, int y, boolean shadow) {
        x += renderer.drawString(text, x, y, colorMap.get(colorStyle).getRGB(), shadow);
        if (endLine)
            y += renderer.FONT_HEIGHT;
        for (val sibling: siblings) {
            x += renderer.drawString(sibling.text, x, y, colorMap.get(sibling.colorStyle).getRGB(), shadow);
        }
    }
}