eorzea-votes/client/EorzeaVotes/Ui/ImGuiHelper.cs

using System.Text;
using Dalamud.Interface;
using EorzeaVotes.Utilities;
using ImGuiNET;
using Regexes = EorzeaVotes.Utilities.Regexes;

namespace EorzeaVotes.Ui;

internal static class ImGuiHelper {
    internal static void Help(string text) {
        ImGui.SameLine();
        ImGui.PushFont(UiBuilder.IconFont);
        using (new OnDispose(ImGui.PopFont)) {
            using var endColour = WithDisabledColour();
            ImGui.TextUnformatted(FontAwesomeIcon.QuestionCircle.ToIconString());
        }

        Tooltip(text);
    }

    internal static OnDispose WithDisabledColour() {
        var disabled = ImGui.GetStyle().Colors[(int) ImGuiCol.TextDisabled];
        ImGui.PushStyleColor(ImGuiCol.Text, disabled);
        return new OnDispose(ImGui.PopStyleColor);
    }

    internal static void Tooltip(string text) {
        if (!ImGui.IsItemHovered()) {
            return;
        }

        ImGui.BeginTooltip();
        using var end = new OnDispose(ImGui.EndTooltip);

        ImGui.PushTextWrapPos(ImGui.CalcTextSize("m").X * 30);
        using var pop = new OnDispose(ImGui.PopTextWrapPos);

        ImGui.TextUnformatted(text);
    }

    internal static bool EnumDropDownVertical<T>(string label, string? nullLabel, ref T? value, string? helpTooltip = null, Func<T?, string>? nameFunction = null)
        where T : struct, Enum {
        const string defaultNullLabel = "None";

        ImGui.TextUnformatted(label);
        if (helpTooltip != null) {
            Help(helpTooltip);
        }

        ImGui.SetNextItemWidth(-1);

        if (!ImGui.BeginCombo($"##{label}", GetName(value))) {
            return false;
        }

        using var end = new OnDispose(ImGui.EndCombo);

        var changed = false;

        if (nullLabel != null && ImGui.Selectable(nullLabel, !value.HasValue)) {
            value = null;
            changed = true;
        }

        foreach (var variant in Enum.GetValues<T>()) {
            if (ImGui.Selectable(GetName(variant), value.HasValue && value.Value.Equals(variant))) {
                value = variant;
                changed = true;
            }
        }

        return changed;

        string GetName(T? t) {
            return nameFunction == null
                ? t == null
                    ? nullLabel ?? defaultNullLabel
                    : Enum.GetName(t.Value) ?? "???"
                : nameFunction(t);
        }
    }

    internal static bool InputDateVertical(string label, ref string input, ref DateOnly? date) {
        ImGui.TextUnformatted(label);
        ImGui.SetNextItemWidth(-1);
        if (!ImGui.InputText($"##{label}", ref input, 10)) {
            return false;
        }

        var match = Regexes.DateRegex().Match(input);
        if (!match.Success) {
            date = null;
            return true;
        }

        var success = true;
        success &= ushort.TryParse(match.Groups[1].Value, out var year);
        success &= byte.TryParse(match.Groups[2].Value, out var month);
        success &= byte.TryParse(match.Groups[3].Value, out var day);

        if (!success) {
            date = null;
            return true;
        }

        var now = DateOnly.FromDateTime(DateTime.UtcNow);
        var valid = year >= now.Year - 115 && year <= now.Year;

        // day and month will be caught be the ctor
        if (!valid) {
            date = null;
            return true;
        }

        try {
            date = new DateOnly(year, month, day);
        } catch {
            date = null;
        }

        return true;
    }

    internal static bool ComboCheckboxVertical(string label, ref bool value) {
        ImGui.TextUnformatted(label);
        ImGui.SetNextItemWidth(-1);
        if (!ImGui.BeginCombo($"##{label}", value ? "Yes" : "No")) {
            return false;
        }

        using var end = new OnDispose(ImGui.EndCombo);

        var changed = false;

        if (ImGui.Selectable("Yes", value)) {
            changed = true;
            value = true;
        }

        if (ImGui.Selectable("No", !value)) {
            changed = true;
            value = false;
        }

        return changed;
    }

    internal static OnDispose? WithDisabled(bool disabled) {
        if (!disabled) {
            return null;
        }

        ImGui.BeginDisabled();
        return new OnDispose(ImGui.EndDisabled);
    }

    /// <summary>
    /// Draw an input with the label above it instead of to the side.
    /// </summary>
    /// <param name="label">Label for the input</param>
    /// <param name="drawInput">Function that draws an input and accepts an ID to be passed to the input label</param>
    /// <param name="appendId">Optional string to be appended to the string passed to <see cref="drawInput"/></param>
    /// <param name="helpTooltip">Optional string to be shown as a help tooltip next to the label</param>
    /// <returns></returns>
    internal static bool VerticalInput(string label, Func<string, bool> drawInput, string? appendId = null, string? helpTooltip = null) {
        ImGui.TextUnformatted(label);
        if (helpTooltip != null) {
            Help(helpTooltip);
        }

        label = $"##{label}";
        if (appendId != null) {
            label += appendId;
        }

        ImGui.SetNextItemWidth(-1);
        return drawInput(label);
    }

    internal static bool IconButton(FontAwesomeIcon icon, string? id = null) {
        ImGui.PushFont(UiBuilder.IconFont);
        using var pop = new OnDispose(ImGui.PopFont);

        var label = icon.ToIconString();
        if (id != null) {
            label += id;
        }

        return ImGui.Button(label);
    }

    internal static unsafe bool BeginTabItem(string label, bool forceOpen = false) {
        var flags = forceOpen
            ? ImGuiTabItemFlags.SetSelected
            : ImGuiTabItemFlags.None;

        var bufSize = Encoding.UTF8.GetByteCount(label);
        var labelBuf = stackalloc byte[bufSize + 1];
        fixed (char* labelPtr = label) {
            Encoding.UTF8.GetBytes(labelPtr, label.Length, labelBuf, bufSize);
        }

        labelBuf[bufSize] = 0;

        return ImGuiNative.igBeginTabItem(labelBuf, null, flags) > 0u;
    }
}