package io.gitlab.jfronny.libjf.config.impl.client.screen;

import io.gitlab.jfronny.libjf.LibJf;
import io.gitlab.jfronny.libjf.config.api.ConfigInstance;
import io.gitlab.jfronny.libjf.config.api.Entry;
import io.gitlab.jfronny.libjf.config.impl.EntryInfo;
import io.gitlab.jfronny.libjf.gson.GsonHidden;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import net.minecraft.client.gui.widget.ButtonWidget;
import net.minecraft.client.gui.widget.TextFieldWidget;
import net.minecraft.text.LiteralText;
import net.minecraft.text.Text;
import net.minecraft.text.TranslatableText;
import net.minecraft.util.Formatting;

import java.util.AbstractMap;
import java.util.Arrays;
import java.util.List;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.regex.Pattern;

@Environment(EnvType.CLIENT)
public class EntryInfoWidgetBuilder {
    private static final Pattern INTEGER_ONLY = Pattern.compile("(-?[0-9]*)");
    private static final Pattern DECIMAL_ONLY = Pattern.compile("-?([\\d]+\\.?[\\d]*|[\\d]*\\.?[\\d]+|\\.)");

    public static void initConfig(ConfigInstance config) {
        for (EntryInfo info : config.getEntries()) {
            if (info.field.isAnnotationPresent(Entry.class) || info.field.isAnnotationPresent(GsonHidden.class))
                try {
                    initEntry(config, info);
                } catch (Exception ignored) {
                }
        }
        for (ConfigInstance value : config.getCategories().values()) {
            initConfig(value);
        }
    }

    private static void initEntry(ConfigInstance config, EntryInfo info) {
        if (!(info.field.isAnnotationPresent(io.gitlab.jfronny.libjf.config.api.Entry.class) || info.field.isAnnotationPresent(GsonHidden.class))) return;
        Class<?> type = info.field.getType();
        info.width = info.entry != null ? info.entry.width() : 0;

        if (info.entry == null) return;

        if (type == int.class || type == Integer.class) textField(config, info, INTEGER_ONLY, Integer::parseInt, true, info.entry.min(), info.entry.max());
        else if (type == float.class || type == Float.class) textField(config, info, DECIMAL_ONLY, Float::parseFloat, false, info.entry.min(), info.entry.max());
        else if (type == double.class || type == Double.class) textField(config, info, DECIMAL_ONLY, Double::parseDouble, false, info.entry.min(), info.entry.max());
        else if (type == String.class) textField(config, info, null, String::length, true, Math.min(info.entry.min(),0), Math.max(info.entry.max(),1));
        else if (type == boolean.class || type == Boolean.class) {
            Function<Object, Text> func = value -> new LiteralText((Boolean) value ? "True" : "False").formatted((Boolean) value ? Formatting.GREEN : Formatting.RED);
            toggle(info, button -> {
                info.value = !(Boolean) info.value;
                button.setMessage(func.apply(info.value));
            }, func);
        } else if (type.isEnum()) {
            List<?> values = Arrays.asList(info.field.getType().getEnumConstants());
            Function<Object,Text> func = value -> new TranslatableText(config.getModId() + ".jfconfig.enum." + type.getSimpleName() + "." + info.value.toString());
            toggle(info, button -> {
                int index = values.indexOf(info.value) + 1;
                info.value = values.get(index >= values.size() ? 0 : index);
                button.setMessage(func.apply(info.value));
            }, func);
        } else LibJf.LOGGER.error("Invalid entry type in " + info.field.getName() + ": " + type.getName());

        try {
            info.value = info.field.get(null);
            info.tempValue = info.value.toString();
        } catch (IllegalAccessException ignored) {
        }
    }

    private static void toggle(EntryInfo info, ButtonWidget.PressAction pressAction, Function<Object, Text> valueTextifier) {
        info.widget = (width, textRenderer, done) -> new ButtonWidget(width - 110, 0, info.width, 20, valueTextifier.apply(info.value), pressAction);
    }

    /**
     * @param config The config this entry is a part of
     * @param info The entry to generate a widget for
     * @param pattern The pattern a valid value must abide to
     * @param sizeFetcher A function to get a number for size constraints
     * @param wholeNumber Whether size constraints are whole numbers
     * @param min The minimum size of a valid value
     * @param max The maximum size of a valid value
     */
    private static void textField(ConfigInstance config, EntryInfo info, Pattern pattern, Function<String, Number> sizeFetcher, boolean wholeNumber, double min, double max) {
        boolean isNumber = pattern != null;
        info.widget = (width, textRenderer, done) -> {
            TextFieldWidget widget = new TextFieldWidget(textRenderer, width - 110, 0, info.width, 20, null);

            widget.setText(info.tempValue);
            Predicate<String> processor = s -> {
                s = s.trim();
                if (!(s.isEmpty() || !isNumber || pattern.matcher(s).matches())) return false;

                Number value = 0;
                boolean inLimits = false;
                info.error = null;
                if (!(isNumber && s.isEmpty()) && !s.equals("-") && !s.equals(".")) {
                    value = sizeFetcher.apply(s);
                    inLimits = value.doubleValue() >= min && value.doubleValue() <= max;
                    info.error = inLimits? null : new AbstractMap.SimpleEntry<>(widget, new LiteralText(value.doubleValue() < min ?
                            "§cMinimum " + (isNumber? "value" : "length") + (wholeNumber ? " is " + (int) min : " is " + min) :
                            "§cMaximum " + (isNumber? "value" : "length") + (wholeNumber ? " is " + (int) max : " is " + max)));
                }

                info.tempValue = s;
                widget.setEditableColor(inLimits? 0xFFFFFFFF : 0xFFFF7777);
                info.inLimits = inLimits;
                done.active = config.getEntries().stream().allMatch(e -> e.inLimits);

                if (inLimits)
                    info.value = isNumber? value : s;

                return true;
            };
            widget.setTextPredicate(processor);

            return widget;
        };
    }
}