UIUtils.hpp

#pragma once
#include "imgui.h"
#include <unordered_map>
#include <string>

// BackdropStyle defines how the small rectangle behind a control is drawn.
// baseColor/hoverColor use IM_COL32 RGBA, padX/padY expand around the item,
// radius controls corner rounding.
struct BackdropStyle {
    ImU32 baseColor;
    ImU32 hoverColor;
    float padX;
    float padY;
    float radius;
};

struct Rect { ImVec2 min; ImVec2 max; };

// Compute the rectangle around the next item based on current cursor position
// and ImGui frame height. Does not depend on draw lists (pure computation).
inline Rect ComputeBackdropRect(ImVec2 cursor, float frameH, const BackdropStyle& s) {
    Rect r;
    r.min = ImVec2(cursor.x - s.padX, cursor.y - s.padY * 0.5f);
    r.max = ImVec2(cursor.x + frameH + s.padX, cursor.y + frameH + s.padY * 0.5f);
    return r;
}

// Draw a backdrop rectangle behind the next item. Call BEFORE rendering the item.
inline void DrawBackdropForNextItem(const BackdropStyle& s) {
    ImDrawList* dl = ImGui::GetWindowDrawList();
    if (!dl) return;
    ImVec2 cursor = ImGui::GetCursorScreenPos();
    float frameH = ImGui::GetFrameHeight() - ImGui::GetStyle().FramePadding.y;
    if (frameH < 12.0f) frameH = ImGui::GetFrameHeight();
    Rect r = ComputeBackdropRect(cursor, frameH, s);
    bool hover = ImGui::IsMouseHoveringRect(r.min, r.max);
    ImU32 col = hover ? s.hoverColor : s.baseColor;
    dl->AddRectFilled(r.min, r.max, col, s.radius);
}

// Draw a full-row backdrop that covers from the current cursor to the right edge
// of the window's content region. Pads and rounds per style. Use for controls
// that include text labels to ensure left/right coverage.
inline void DrawBackdropRowFull(const BackdropStyle& s) {
    ImDrawList* dl = ImGui::GetWindowDrawList();
    if (!dl) return;
    ImVec2 cursor = ImGui::GetCursorScreenPos();
    ImVec2 winPos = ImGui::GetWindowPos();
    float full = ImGui::GetContentRegionAvail().x;
    float frameH = ImGui::GetFrameHeight() - ImGui::GetStyle().FramePadding.y;
    if (frameH < 12.0f) frameH = ImGui::GetFrameHeight();
    Rect r = ComputeBackdropRect(cursor, frameH, s);
    r.max.x = cursor.x + full + s.padX; // extend to right edge
    bool hover = ImGui::IsMouseHoveringRect(r.min, r.max);
    ImU32 col = hover ? s.hoverColor : s.baseColor;
    dl->AddRectFilled(r.min, r.max, col, s.radius);
}

/**
 * @function FeatureCheckbox
 * @description Renders a checkbox with animated text color based on activation state.
 * @param {const char*} name - Feature display name
 * @param {bool*} active - Pointer to current activation status; true = green, false = red
 * @returns {bool} true if the checkbox value changed
 */
inline bool FeatureCheckbox(const char* name, bool* active) {
    if (!name || !active) return false;
    static std::unordered_map<std::string, float> anim;
    float& a = anim[std::string(name)];
    float target = *active ? 1.0f : 0.0f;
    float dt = ImGui::GetIO().DeltaTime;
    a += (target - a) * (dt * 12.0f);
    if (a < 0.0f) a = 0.0f; if (a > 1.0f) a = 1.0f;
    ImVec4 red = ImVec4(1.0f, 0.0f, 0.0f, 1.0f);
    ImVec4 green = ImVec4(0.0f, 1.0f, 0.0f, 1.0f);
    ImVec4 mix = ImVec4(
        red.x + (green.x - red.x) * a,
        red.y + (green.y - red.y) * a,
        red.z + (green.z - red.z) * a,
        1.0f
    );
    ImGui::PushStyleColor(ImGuiCol_Text, mix);
    bool changed = ImGui::Checkbox(name, active);
    ImGui::PopStyleColor();
    return changed;
}

/**
 * @function ComputeFeatureColor
 * @description Returns the current animated color for a feature without rendering.
 * @param {const char*} name - Feature name key
 * @param {bool} active - Activation state
 * @returns {ImVec4} RGBA color
 */
inline ImVec4 ComputeFeatureColor(const char* name, bool active) {
    static std::unordered_map<std::string, float> anim;
    float& a = anim[std::string(name ? name : "__invalid__")];
    float target = active ? 1.0f : 0.0f;
    float dt = ImGui::GetIO().DeltaTime;
    a += (target - a) * (dt * 12.0f);
    if (a < 0.0f) a = 0.0f; if (a > 1.0f) a = 1.0f;
    ImVec4 red = ImVec4(1.0f, 0.0f, 0.0f, 1.0f);
    ImVec4 green = ImVec4(0.0f, 1.0f, 0.0f, 1.0f);
    return ImVec4(
        red.x + (green.x - red.x) * a,
        red.y + (green.y - red.y) * a,
        red.z + (green.z - red.z) * a,
        1.0f
    );
}