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

import io.gitlab.jfronny.commons.throwable.Try;
import io.gitlab.jfronny.commons.tuple.Tuple;
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.api.EntryInfo;
import io.gitlab.jfronny.libjf.config.api.WidgetFactory;
import io.gitlab.jfronny.libjf.config.impl.EntryInfoImpl;
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.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.function.Function;
import java.util.regex.Pattern;

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

    public static List<WidgetState<?>> buildWidgets(ConfigInstance config) {
        WidgetState<?> state;
        List<WidgetState<?>> knownStates = new ArrayList<>();
        for (EntryInfo<?> info : config.getEntries()) {
            if ((state = initEntry(config, info, knownStates)) != null) {
                knownStates.add(state);
            }
        }
        return knownStates;
    }

    private static <T> WidgetState<T> initEntry(ConfigInstance config, EntryInfo<T> info, List<WidgetState<?>> knownStates) {
        Class<T> type = info.getValueType();
        WidgetState<T> state = new WidgetState<>();
        WidgetFactory factory;

        if (type == int.class || type == Integer.class) factory = textField(info, state, INTEGER_ONLY, Integer::parseInt, true, info.getMinValue(), info.getMaxValue());
        else if (type == float.class || type == Float.class) factory = textField(info, state, DECIMAL_ONLY, Float::parseFloat, false, info.getMinValue(), info.getMaxValue());
        else if (type == double.class || type == Double.class) factory = textField(info, state, DECIMAL_ONLY, Double::parseDouble, false, info.getMinValue(), info.getMaxValue());
        else if (type == String.class) factory = textField(info, state, null, String::length, true, Math.min(info.getMinValue(),0), Math.max(info.getMaxValue(),1));
        else if (type == boolean.class || type == Boolean.class) {
            factory = toggle(info, state,
                    value -> !(Boolean) value,
                    value -> new LiteralText((Boolean) value ? "True" : "False").formatted((Boolean) value ? Formatting.GREEN : Formatting.RED));
        } else if (type.isEnum()) {
            List<T> values = Arrays.asList(info.getValueType().getEnumConstants());
            factory = toggle(info, state, value -> {
                int index = values.indexOf(value) + 1;
                return values.get(index >= values.size() ? 0 : index);
            }, value -> new TranslatableText(config.getModId() + ".jfconfig.enum." + type.getSimpleName() + "." + state.cachedValue));
        } else {
            LibJf.LOGGER.error("Invalid entry type in " + info.getName() + ": " + type.getName());
            factory = ((screenWidth, textRenderer, done) -> new WidgetFactory.Widget(() -> {}, new ButtonWidget(-10, 0, 0, 0, Text.of(""), null)));
        }

        Try.orThrow(() -> state.initialize(info, knownStates, factory));
        return state;
    }

    private static <T> WidgetFactory toggle(EntryInfo<T> info, WidgetState<T> state, Function<Object, Object> increment, Function<T, Text> valueTextifier) {
        return (screenWidth, textRenderer, done) -> {
            ButtonWidget button = new ButtonWidget(screenWidth - 110, 0, info.getWidth(), 20, valueTextifier.apply(state.cachedValue), btn -> {
                state.updateCache((T) increment.apply(state.cachedValue));
                btn.setMessage(valueTextifier.apply(state.cachedValue));
            });
            return new WidgetFactory.Widget(() -> button.setMessage(valueTextifier.apply(state.cachedValue)), button);
        };
    }

    /**
     * @param info The entry to generate a widget for
     * @param state The state representation of this widget
     * @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 <T> WidgetFactory textField(EntryInfo<T> info, WidgetState<T> state, Pattern pattern, Function<String, Number> sizeFetcher, boolean wholeNumber, double min, double max) {
        boolean isNumber = pattern != null;
        return (width, textRenderer, done) -> {
            TextFieldWidget widget = new TextFieldWidget(textRenderer, width - 110, 0, info.getWidth(), 20, null);

            widget.setText(state.tempValue);
            widget.setTextPredicate(currentInput -> {
                currentInput = currentInput.trim();
                if (!(currentInput.isEmpty() || !isNumber || pattern.matcher(currentInput).matches())) return false;

                Number value = 0;
                boolean inLimits = false;
                state.error = null;
                if (!(isNumber && currentInput.isEmpty()) && !currentInput.equals("-") && !currentInput.equals(".")) {
                    value = sizeFetcher.apply(currentInput);
                    inLimits = value.doubleValue() >= min && value.doubleValue() <= max;
                    state.error = inLimits ? null : Tuple.of(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)));
                }

                state.tempValue = currentInput;
                widget.setEditableColor(inLimits? 0xFFFFFFFF : 0xFFFF7777);
                state.inLimits = inLimits;
                done.active = state.knownStates.stream().allMatch(st -> st.inLimits);

                if (inLimits) {
                    //Coerce.consumer(info::setValue).addHandler(e -> {}).accept(isNumber ? (T) value : (T) currentInput);
                    state.cachedValue = isNumber ? (T) value : (T) currentInput;
                }

                return true;
            });

            return new WidgetFactory.Widget(() -> widget.setText(state.cachedValue == null ? "" : state.cachedValue.toString()), widget);
        };
    }
}