//  SPDX-License-Identifier: MIT
//
//  EmulationStation Desktop Edition
//  HelpComponent.cpp
//
//  Help information in icon and text pairs.
//

#include "components/HelpComponent.h"

#include "components/ComponentGrid.h"
#include "components/ImageComponent.h"
#include "components/TextComponent.h"
#include "resources/TextureResource.h"
#include "utils/StringUtil.h"
#include "Log.h"
#include "Settings.h"

#define OFFSET_X 12 // Move the entire thing right by this amount (px).
#define OFFSET_Y 12 // Move the entire thing up by this amount (px).

#define ICON_TEXT_SPACING 8 // Space between [icon] and [text] (px).
#define ENTRY_SPACING 16 // Space between [text] and next [icon] (px).

static const std::map<std::string, std::string> ICON_PATH_MAP {
    { "up/down", ":/help/dpad_updown.svg" },
    { "left/right", ":/help/dpad_leftright.svg" },
    { "up/down/left/right", ":/help/dpad_all.svg" },
    { "thumbstickclick", ":/help/thumbstick_click.svg" },
    { "a", ":/help/button_a.svg" },
    { "b", ":/help/button_b.svg" },
    { "x", ":/help/button_x.svg" },
    { "y", ":/help/button_y.svg" },
    { "l", ":/help/button_l.svg" },
    { "r", ":/help/button_r.svg" },
    { "lr", ":/help/button_lr.svg" },
    { "start", ":/help/button_start.svg" },
    { "select", ":/help/button_select.svg" }
};

HelpComponent::HelpComponent(Window* window) : GuiComponent(window)
{
}

void HelpComponent::clearPrompts()
{
    mPrompts.clear();
    updateGrid();
}

void HelpComponent::setPrompts(const std::vector<HelpPrompt>& prompts)
{
    mPrompts = prompts;
    updateGrid();
}

void HelpComponent::setStyle(const HelpStyle& style)
{
    mStyle = style;
    updateGrid();
}

void HelpComponent::updateGrid()
{
    if (!Settings::getInstance()->getBool("ShowHelpPrompts") || mPrompts.empty()) {
        mGrid.reset();
        return;
    }

    std::shared_ptr<Font>& font = mStyle.font;

    mGrid = std::make_shared<ComponentGrid>(mWindow,
            Vector2i(static_cast<int>(mPrompts.size()) * 4, 1));

    // [icon] [spacer1] [text] [spacer2]

    std::vector<std::shared_ptr<ImageComponent>> icons;
    std::vector<std::shared_ptr<TextComponent>> labels;

    float width = 0;
    const float height = std::round(font->getLetterHeight() * 1.25f);

    for (auto it = mPrompts.cbegin(); it != mPrompts.cend(); it++) {
        auto icon = std::make_shared<ImageComponent>(mWindow);
        icon->setImage(getIconTexture(it->first.c_str()));
        icon->setColorShift(mStyle.iconColor);
        icon->setResize(0, height);
        icons.push_back(icon);

        auto lbl = std::make_shared<TextComponent>(mWindow,
                Utils::String::toUpper(it->second), font, mStyle.textColor);
        labels.push_back(lbl);

        width += icon->getSize().x() + lbl->getSize().x() +
                ((ICON_TEXT_SPACING + ENTRY_SPACING) * Renderer::getScreenWidthModifier());
    }

    mGrid->setSize(width, height);

    for (unsigned int i = 0; i < icons.size(); i++) {
        const int col = i*4;
        mGrid->setColWidthPerc(col, icons.at(i)->getSize().x() / width);
        mGrid->setColWidthPerc(col + 1, (ICON_TEXT_SPACING *
                Renderer::getScreenWidthModifier()) / width);
        mGrid->setColWidthPerc(col + 2, labels.at(i)->getSize().x() / width);

        mGrid->setEntry(icons.at(i), Vector2i(col, 0), false, false);
        mGrid->setEntry(labels.at(i), Vector2i(col + 2, 0), false, false);
    }

    mGrid->setPosition(Vector3f(mStyle.position.x(), mStyle.position.y(), 0.0f));
    //mGrid->setPosition(OFFSET_X, Renderer::getScreenHeight() - mGrid->getSize().y() - OFFSET_Y);
    mGrid->setOrigin(mStyle.origin);
}

std::shared_ptr<TextureResource> HelpComponent::getIconTexture(const char* name)
{
    auto it = mIconCache.find(name);
    if (it != mIconCache.cend())
        return it->second;

    auto pathLookup = ICON_PATH_MAP.find(name);
    if (pathLookup == ICON_PATH_MAP.cend()) {
        LOG(LogError) << "Unknown help icon \"" << name << "\"!";
        return nullptr;
    }
    if (!ResourceManager::getInstance()->fileExists(pathLookup->second)) {
        LOG(LogError) << "Help icon \"" << name <<
                "\" - corresponding image file \"" << pathLookup->second << "\" misisng!";
        return nullptr;
    }

    std::shared_ptr<TextureResource> tex = TextureResource::get(pathLookup->second);
    mIconCache[std::string(name)] = tex;
    return tex;
}

void HelpComponent::setOpacity(unsigned char opacity)
{
    GuiComponent::setOpacity(opacity);

    for (unsigned int i = 0; i < mGrid->getChildCount(); i++)
        mGrid->getChild(i)->setOpacity(opacity);
}

void HelpComponent::render(const Transform4x4f& parentTrans)
{
    Transform4x4f trans = parentTrans * getTransform();

    if (mGrid)
        mGrid->render(trans);
}