#include "ui/Menu.hpp"

#include "config/config.hpp"
#include "graphics/colors.hpp"
#include "input.hpp"
#include "mathutil.hpp"
#include "ui/BoundingBox.hpp"

#include <cmath>

ui::Menu::Menu(int x, int y, int width, int fontSize, int renderTargetHeight)
    : m_x(x)
    , m_y(y)
    , m_optionHeight(std::floor(static_cast<double>(fontSize) * 1.8f))
    , m_optionTarget(
          sdl::TextureManager::load("MENU_" + std::to_string(sm_menuID++), width, m_optionHeight, SDL_TEXTUREACCESS_TARGET))
    , m_boundingBox(ui::BoundingBox::create(0, 0, width + 12, m_optionHeight + 12))
    , m_originalY(y)
    , m_targetY(y)
    , m_maxDisplayOptions((renderTargetHeight - m_originalY) / m_optionHeight)
    , m_scrollLength(std::floor(static_cast<double>(m_maxDisplayOptions) / 2))
    , m_width(width)
    , m_fontSize(fontSize)
    , m_textY((m_optionHeight / 2) - (m_fontSize / 2)) // This seems to be the best alignment.
    , m_renderTargetHeight(renderTargetHeight)
    , m_optionScroll(
          ui::TextScroll::create({}, 16, 0, m_width, m_optionHeight, m_fontSize, colors::BLUE_GREEN, colors::TRANSPARENT)) {};

void ui::Menu::update(bool hasFocus)
{
    if (m_options.empty()) { return; }

    m_boundingBox->update(hasFocus);
    m_optionScroll->update(hasFocus);

    Menu::handle_input();
    Menu::update_scrolling();
    Menu::update_scroll_text();
}

void ui::Menu::render(sdl::SharedTexture &target, bool hasFocus)
{
    if (m_options.empty()) { return; }

    // I hate doing this.
    const int optionSize = m_options.size();
    for (int i = 0, tempY = m_y; i < optionSize; i++, tempY += m_optionHeight)
    {
        if (tempY < -m_fontSize) { continue; }
        else if (tempY > m_renderTargetHeight) { break; }

        m_optionTarget->clear(colors::TRANSPARENT);

        if (i == m_selected)
        {
            if (hasFocus)
            {
                m_boundingBox->set_x(m_x - 4);
                m_boundingBox->set_y(tempY - 4);
                m_boundingBox->render(target, hasFocus);
            }
            sdl::render_rect_fill(m_optionTarget, 8, 8, 4, m_optionHeight - 14, colors::BLUE_GREEN);
            m_optionScroll->render(m_optionTarget, hasFocus);
        }
        else { sdl::text::render(m_optionTarget, 24, m_textY, m_fontSize, sdl::text::NO_WRAP, colors::WHITE, m_options[i]); }
        // render target to target
        m_optionTarget->render(target, m_x, tempY);
    }
}

void ui::Menu::add_option(std::string_view newOption)
{
    // This is needed. The initialization is just a temporary one.
    if (m_options.empty()) { m_optionScroll->set_text(newOption, false); }
    m_options.push_back(newOption.data());
}

void ui::Menu::add_option(std::string &newOption)
{
    if (m_options.empty()) { m_optionScroll->set_text(newOption, false); }
    m_options.push_back(std::move(newOption));
}

void ui::Menu::edit_option(int index, std::string_view newOption)
{
    const int optionSize = m_options.size();
    if (index < 0 || index >= optionSize) { return; }
    m_options[index] = newOption.data();
}

int ui::Menu::get_selected() const noexcept { return m_selected; }

void ui::Menu::set_selected(int selected)
{
    m_selected = selected;
    Menu::update_scroll_text();
}
void ui::Menu::set_x(int x) noexcept { m_x = x; }

void ui::Menu::set_y(int y) noexcept { m_y = y; }

void ui::Menu::set_width(int width) noexcept { m_width = width; }

void ui::Menu::reset(bool full)
{
    if (full)
    {
        m_selected = 0;
        m_y        = m_originalY;
    }

    m_options.clear();
}

bool ui::Menu::is_empty() const noexcept { return m_options.empty(); }

void ui::Menu::update_scroll_text()
{
    const std::string_view text   = m_optionScroll->get_text();
    const std::string_view option = m_options[m_selected];
    if (text != option) { m_optionScroll->set_text(option, false); }
}

void ui::Menu::handle_input()
{
    const bool upPressed        = input::button_pressed(HidNpadButton_AnyUp);
    const bool downPressed      = input::button_pressed(HidNpadButton_AnyDown);
    const bool leftPressed      = input::button_pressed(HidNpadButton_AnyLeft);
    const bool rightPressed     = input::button_pressed(HidNpadButton_AnyRight);
    const bool lShoulderPressed = input::button_pressed(HidNpadButton_L);
    const bool rShoulderPressed = input::button_pressed(HidNpadButton_R);
    const int optionsSize       = m_options.size();

    if (upPressed) { --m_selected; }
    else if (downPressed) { ++m_selected; }
    else if (leftPressed) { m_selected -= m_scrollLength; }
    else if (rightPressed) { m_selected += m_scrollLength; }
    else if (lShoulderPressed) { m_selected -= m_scrollLength * 3; }
    else if (rShoulderPressed) { m_selected += m_scrollLength * 3; }

    if (m_selected < 0) { m_selected = 0; }
    else if (m_selected >= optionsSize) { m_selected = optionsSize - 1; }
}

void ui::Menu::update_scrolling()
{
    const int optionsSize = m_options.size();
    if (optionsSize <= m_maxDisplayOptions) { return; }

    const int endScrollPoint = optionsSize - (m_maxDisplayOptions - m_scrollLength);
    const int scrolledItems  = m_selected - m_scrollLength;
    const double scaling     = config::get_animation_scaling();

    if (m_selected < m_scrollLength) { m_targetY = m_originalY; } // Don't bother. There's no point.
    else if (m_selected >= endScrollPoint) { m_targetY = m_originalY - (optionsSize - m_maxDisplayOptions) * m_optionHeight; }
    else if (m_selected >= m_scrollLength) { m_targetY = m_originalY - (scrolledItems * m_optionHeight); }

    if (m_y != m_targetY)
    {
        m_y += std::round((m_targetY - m_y) / scaling);

        const int distance = math::Util<double>::absolute_distance(m_y, m_targetY);
        if (distance <= 2) { m_y = m_targetY; }
    }
}