/*
Crafter®.Graphics
Copyright (C) 2025 Catcrafts®
Catcrafts.net

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 3.0 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
*/

module;
#define STB_IMAGE_IMPLEMENTATION
#include "../lib/stb_image.h"
#include "../lib/stb_truetype.h"
module Crafter.Graphics:UiElement_impl;
import :UiElement;
import :Font;
import std;

using namespace Crafter;

UiElement::UiElement(float anchorX, float anchorY, float relativeWidth, float relativeHeight, float anchorOffsetX, float anchorOffsetY, float z, bool ignoreScaling) : anchorX(anchorX), anchorY(anchorY), relativeWidth(relativeWidth), relativeHeight(relativeHeight), anchorOffsetX(anchorOffsetX), anchorOffsetY(anchorOffsetY), z(z), useRelativeSize(true), ignoreScaling(ignoreScaling) {

}

UiElement::UiElement(float anchorX, float anchorY, std::uint32_t bufferWidth, std::uint32_t bufferHeight, std::uint32_t absoluteWidth, std::uint32_t absoluteHeight, float anchorOffsetX, float anchorOffsetY, float z, bool ignoreScaling) : anchorX(anchorX), anchorY(anchorY), bufferWidth(bufferWidth), bufferHeight(bufferHeight), absoluteWidth(absoluteWidth), absoluteHeight(absoluteHeight), anchorOffsetX(anchorOffsetX), anchorOffsetY(anchorOffsetY), z(z), buffer(bufferWidth*bufferHeight), useRelativeSize(false), ignoreScaling(ignoreScaling) {

}

UiElement::UiElement(float anchorX, float anchorY, std::uint32_t bufferWidth, std::uint32_t bufferHeight, float relativeWidth, float relativeHeight, float anchorOffsetX, float anchorOffsetY, float z, bool ignoreScaling) : anchorX(anchorX), anchorY(anchorY), bufferWidth(bufferWidth), bufferHeight(bufferHeight), relativeWidth(relativeWidth), relativeHeight(relativeHeight), anchorOffsetX(anchorOffsetX), anchorOffsetY(anchorOffsetY), z(z), buffer(bufferWidth*bufferHeight), useRelativeSize(true), ignoreScaling(ignoreScaling) {

}

UiElement::UiElement(const std::filesystem::path& image, float anchorX, float anchorY, float relativeWidth, float relativeHeight, float anchorOffsetX, float anchorOffsetY, float z, bool ignoreScaling) : anchorX(anchorX), anchorY(anchorY), relativeWidth(relativeWidth), relativeHeight(relativeHeight), anchorOffsetX(anchorOffsetX), anchorOffsetY(anchorOffsetY), z(z), useRelativeSize(true), ignoreScaling(ignoreScaling) {
    std::filesystem::path abs = std::filesystem::absolute(image);
    int xSize;
    int ySize;
    unsigned char* bgData = stbi_load(abs.string().c_str(), &xSize, &ySize, nullptr, 4);

    bufferWidth = xSize;
    bufferHeight = ySize;

    buffer.resize(bufferWidth*bufferHeight);

    for(std::uint_fast32_t x = 0; x < xSize; x++) {
		for(std::uint_fast32_t y = 0; y < ySize; y++) {
            std::uint_fast32_t idx = (x*ySize+y)*4;
			buffer[x*ySize+y].r = bgData[idx];
			buffer[x*ySize+y].g = bgData[idx+1];
			buffer[x*ySize+y].b = bgData[idx+2];
			buffer[x*ySize+y].a = bgData[idx+3];
		}
	}
}

TextElement::TextElement(const std::string_view text,  float size, Pixel_BU8_GU8_RU8_AU8 color, const Font& font, float anchorX, float anchorY, float relativeWidth, float relativeHeight, float anchorOffsetX, float anchorOffsetY, float z, bool ignoreScaling) : UiElement(anchorX, anchorY, relativeWidth, relativeHeight, anchorOffsetX, anchorOffsetY, z, ignoreScaling) {
    RenderText(text, size, color, font);
}

void TextElement::RenderText(const std::string_view text, float size, Pixel_BU8_GU8_RU8_AU8 color, const Font& font) {
    float scale = stbtt_ScaleForPixelHeight(&font.font, size);

    int baseline = (int)(font.ascent * scale);

    bufferWidth = 0;
    bufferHeight = (int)((font.ascent -font.descent) * scale);
    for (const char c : text) {
        int advance, lsb;
        stbtt_GetCodepointHMetrics(&font.font, c, &advance, &lsb);
        bufferWidth += (int)(advance * scale);
    }

    buffer.resize(bufferWidth * bufferHeight);

    int x = 0;
    for (std::uint_fast32_t i = 0; i < text.size(); i++) {
        int codepoint = text[i];

        int ax;
        int lsb;
        stbtt_GetCodepointHMetrics(&font.font, codepoint, &ax, &lsb);

        int c_x1, c_y1, c_x2, c_y2;
        stbtt_GetCodepointBitmapBox(&font.font, codepoint, scale, scale, &c_x1, &c_y1, &c_x2, &c_y2);

        int w = c_x2 - c_x1;
        int h = c_y2 - c_y1;

        std::vector<unsigned char> bitmap(w * h);
        stbtt_MakeCodepointBitmap(&font.font, bitmap.data(), w, h, w, scale, scale, codepoint);

        for (int j = 0; j < h; j++) {
            for (int i = 0; i < w; i++) {
                int bufIndex = ((baseline + j + c_y1) * bufferWidth + (x + i + c_x1));
                unsigned char val = bitmap[j * w + i];
                buffer[bufIndex] = {color.r, color.g, color.b, val};
            }
        }

        x += (int)(ax * scale);

        if (i + 1 < text.size()) {
            x += (int)stbtt_GetCodepointKernAdvance(&font.font, codepoint, text[i+1] * scale);
        }
    }
}