#include <cmath>
#include <memory>
#include <algorithm>
#include "bmpimage.h"

BMPImage::BMPImage(const BitmapFileHeader &fileHeader, const BITMAPINFOHEADER &infoHeader, const PixelArray &pixelArray)
        : pixelArray(pixelArray) {
    this->fileHeader = fileHeader;
    this->infoHeader = infoHeader;
}


//BMPImage::BMPImage(const BitmapFileHeader &fileHeader, const BITMAPINFOHEADER &infoHeader, PixelArray pixelArray) {
//
//}

const uint32_t &BMPImage::width() const { return this->infoHeader.BitmapWidth; }

const uint32_t &BMPImage::height() const { return this->infoHeader.BitmapHeight; }

void BMPImage::save(const std::string &filename) {
    {
        std::ofstream ofs(filename, std::ios_base::binary);
        ofs.write((char *) &this->fileHeader, sizeof(this->fileHeader));
        ofs.write((char *) &this->infoHeader, sizeof(this->infoHeader));
        uint32_t byteByRow = this->infoHeader.BitmapWidth * 3;
        uint8_t padding = (4 - byteByRow % 4) % 4;
        for (auto i = (int) this->infoHeader.BitmapHeight - 1; i > -1; --i) {
            ofs.write((char *) pixelArray(i), byteByRow);
            if (padding != 4) ofs.write(PADDING_ZEROES, padding); // Write padding
        }
    }
}

PixelArray BMPImage::pixels() {
    return this->pixelArray;
}

PixelArray BMPImage::pixels_copy() {
//    Pixel **newPixelArray;
    PixelArray newPixelArray(this->infoHeader.BitmapWidth, this->infoHeader.BitmapHeight);
//    newPixelArray = new Pixel *[this->infoHeader.BitmapHeight];
    for (int i = 0; i < this->infoHeader.BitmapHeight; ++i) {
//        newPixelArray[i] = new Pixel[this->infoHeader.BitmapWidth];
//        std::copy(this->pixelArray(i), this->pixelArray(i) + this->infoHeader.BitmapWidth, newPixelArray(i)); // TODO
        for (int j = 0; j < this->infoHeader.BitmapWidth; ++j) {
            newPixelArray(i, j) = this->pixelArray(i, j);
        }
    }
    return newPixelArray;
}

BitmapFileHeader BMPImage::fileHeader_copy() {
    return this->fileHeader;
}

BITMAPINFOHEADER BMPImage::infoHeader_copy() {
    return this->infoHeader;
}

BMPImage::~BMPImage() {
//    delete pixelArray;
//    for (int i = 0; i < this->infoHeader.BitmapHeight; ++i) {
//        delete[] this->pixelArray(i);
//    }
//    delete[] this->pixelArray;
}

BMPImage::BMPImage(const PixelArray &pixelArray) : pixelArray(pixelArray) {
    uint32_t width = pixelArray.width();
    uint32_t height = pixelArray.height();
    BitmapFileHeader _fileHeader;
    BITMAPINFOHEADER _infoHeader;
    _infoHeader.BitmapWidth = width;
    _infoHeader.BitmapHeight = height;
    _infoHeader.ImageSize = width * height * 3 + ((4 - (width * 3) % 4) % 4) * height;
    _fileHeader.fileSize = _infoHeader.ImageSize + _fileHeader.imageDataOffset;
    this->infoHeader = _infoHeader;
    this->fileHeader = _fileHeader;
//    this->pixelArray = pixelArray;
}

BMPImage BMPImage::appendRight(BMPImage &img) {
    uint32_t newHeight = std::max(this->infoHeader.BitmapHeight, img.height());
    uint32_t newWidth = this->infoHeader.BitmapWidth + img.width();
//    Pixel **newPixelArray;
    PixelArray newPixelArray(newWidth, newHeight);
//    std::shared_ptr<PixelArray> newPixelArray = std::make_shared<PixelArray>(newWidth, newHeight);
//    newPixelArray = new Pixel *[newHeight];
    for (int i = 0; i < this->infoHeader.BitmapHeight; ++i) {
//        newPixelArray[i] = new Pixel[newWidth];
        std::copy(this->pixelArray(i), this->pixelArray(i) + this->infoHeader.BitmapWidth, newPixelArray(i));
    }
    for (int i = 0; i < img.height(); ++i) {
        std::copy(img.pixels()(i), img.pixelArray(i) + img.width(), newPixelArray(i) + this->infoHeader.BitmapWidth);
    }

    return {newPixelArray};
}

BMPImage BMPImage::overlay(BMPImage &img, uint32_t pos_x, uint32_t pos_y) {
    if (pos_x + img.width() > this->width() || pos_y + img.height() > this->height())
        throw std::runtime_error("The overlaid image is outside the image");
    auto pixels = this->pixels_copy();
    for (int i = 0; i < img.height(); ++i) {
        std::copy(img.pixels()(i), img.pixels()(i) + img.width(), pixels(pos_y + i) + pos_x);
    }
    return {pixels};
}

BMPImage BMPImage::applyFilter(const std::function<uint8_t(std::array<int, 9> &)> &filter) {
    auto origPixels = this->pixels_copy();
    PixelArray pixels(this->width(), this->height());
    for (int y = 1; y < this->height() - 1; ++y) {
        for (int x = 1; x < this->width() - 1; ++x) {
            auto p1 = origPixels(y - 1, x - 1);
            auto p2 = origPixels(y - 1, x);
            auto p3 = origPixels(y - 1, x + 1);
            auto p4 = origPixels(y, x - 1);
            auto p5 = origPixels(y, x);
            auto p6 = origPixels(y, x + 1);
            auto p7 = origPixels(y + 1, x - 1);
            auto p8 = origPixels(y + 1, x);
            auto p9 = origPixels(y + 1, x + 1);
            std::array<int, 9> red_channel = {p1.r, p2.r, p3.r, p4.r, p5.r, p6.r, p7.r, p8.r, p9.r};
            std::array<int, 9> green_channel = {p1.g, p2.g, p3.g, p4.g, p5.g, p6.g, p7.g, p8.g, p9.g};
            std::array<int, 9> blue_channel = {p1.b, p2.b, p3.b, p4.b, p5.b, p6.b, p7.b, p8.b, p9.b};
            auto r = filter(red_channel);
            auto g = filter(green_channel);
            auto b = filter(blue_channel);
            pixels(y, x) = {r, g, b};
        }
    }
    return {pixels};
}


BMPImage readBMPImage(const std::string &filename) {
    BitmapFileHeader bitmapFileHeader;
    BITMAPINFOHEADER bitmapInfoHeader;
    uint32_t DIB_Header_Size;
    {
        std::ifstream ifs(filename, std::ios_base::binary);
        if (!ifs.good()) {
            throw std::runtime_error("File read error");
        }
        ifs.seekg(0, std::ios::beg);
        ifs.read((char *) &bitmapFileHeader, sizeof(bitmapFileHeader));
        ifs.read((char *) &DIB_Header_Size, sizeof(DIB_Header_Size));
    }
    if (DIB_Header_Size != 40) {
        throw std::runtime_error("Invalid header");
    }
    {
        std::ifstream ifs(filename, std::ios_base::binary);
        if (!ifs.good()) {
            throw std::runtime_error("File read error");
        }
        ifs.seekg(14, std::ios::beg);
        ifs.read((char *) &bitmapInfoHeader, sizeof(bitmapInfoHeader));
    }
    PixelArray pixelArray = PixelArray(bitmapInfoHeader.BitmapWidth, bitmapInfoHeader.BitmapHeight);
//    pixelArray = new Pixel *[bitmapInfoHeader.BitmapHeight];
    {
        std::ifstream ifs(filename, std::ios_base::binary);
        if (!ifs.good()) {
            throw std::runtime_error("File read error");
        }
        ifs.seekg(bitmapFileHeader.imageDataOffset, std::ios::beg);
        uint32_t byteByRow = bitmapInfoHeader.BitmapWidth * 3;
        uint8_t padding = (4 - byteByRow % 4) % 4;
        for (auto i = (int) bitmapInfoHeader.BitmapHeight - 1; i > -1; --i) {
//            pixelArray(i) = new Pixel[bitmapInfoHeader.BitmapWidth];
            ifs.read((char *) pixelArray(i), byteByRow);
            if (padding != 4) ifs.seekg(padding, std::ios_base::cur); // Skip padding
        }
    }
    return {bitmapFileHeader, bitmapInfoHeader, pixelArray};
}


BMPImage grayscale(BMPImage &img) {
    auto pixels = img.pixels_copy();
    for (int i = 0; i < img.height(); ++i) {
        for (int j = 0; j < img.width(); ++j) {
            uint8_t gray = pixels(i, j).r / 3 + pixels(i, j).g / 3 + pixels(i, j).b / 3;
            pixels(i, j) = {gray, gray, gray};
        }
    }
    return {img.fileHeader_copy(), img.infoHeader_copy(), pixels};
}


BMPImage invertColors(BMPImage &img) {
    auto pixels = img.pixels_copy();
    for (int i = 0; i < img.height(); ++i) {
        for (int j = 0; j < img.width(); ++j) {
            pixels(i, j) = 255 - pixels(i, j);
        }
    }
    return {img.fileHeader_copy(), img.infoHeader_copy(), pixels};
}

BMPImage upscale2x(BMPImage &img) {
    auto oldPixels = img.pixels();
    const uint32_t newHeight = img.height() * 2;
    const uint32_t newWidth = img.width() * 2;
    PixelArray newPixelArray(newWidth, newHeight);
    for (int i = 0; i < newHeight; i += 2) {
        for (int j = 0; j < newWidth; ++j) {
            if (j % 2 == 0)
                newPixelArray(i, j) = oldPixels(i / 2, j / 2);
            else if (j == newWidth - 1)
                newPixelArray(i, j) = oldPixels(i / 2, j / 2) / 2;
            else
                newPixelArray(i, j) = oldPixels(i / 2, j / 2) / 2 + oldPixels(i / 2, j / 2 + 1) / 2;
        }
    }
    for (int i = 1; i < newHeight; i += 2) {
        if (i == newHeight - 1)
            for (int j = 0; j < newWidth; ++j) {
                newPixelArray(i, j) = newPixelArray(i - 1, j) / 2;
            }
        else
            for (int j = 0; j < newWidth; ++j) {
                newPixelArray(i, j) = newPixelArray(i - 1, j) / 2 + newPixelArray(i + 1, j) / 2;
            }
    }
    return {newPixelArray};
}

BMPImage downscale2x(BMPImage &img) {
    auto oldPixels = img.pixels_copy();
    const uint32_t newHeight = img.height() / 2;
    const uint32_t newWidth = img.width() / 2;
    PixelArray newPixelArray(newWidth, newHeight);
    for (int i = 0; i < newHeight; ++i) {
        for (int j = 0; j < newWidth; ++j) {
            newPixelArray(i, j) = oldPixels(i * 2, j * 2);
        }
    }
    return {newPixelArray};
}

BMPImage upscale1_5x(BMPImage &img) {
    auto oldPixels = img.pixels();
    const uint32_t newHeight = img.height() * 3 / 2;
    const uint32_t newWidth = img.width() * 3 / 2;
    PixelArray newPixelArray(newWidth, newHeight);
    for (int i = 0; i < newHeight; ++i) {
        if ((i + 1) % 3 == 0) continue;
        for (int j = 0; j < newWidth; ++j) {
            int oldi = i * 2 / 3;
            int oldj = j * 2 / 3;
            if ((j + 1) % 3 != 0)
                newPixelArray(i, j) = oldPixels(oldi, oldj);
            else if (j == newWidth - 1)
                newPixelArray(i, j) = oldPixels(oldi, oldj) / 2;
            else
                newPixelArray(i, j) = oldPixels(oldi, oldj) / 2 + oldPixels(oldi, oldj + 1) / 2;
        }
    }
    for (int i = 2; i < newHeight; i += 3) {
        if (i == newHeight - 1)
            for (int j = 0; j < newWidth; ++j) {
                newPixelArray(i, j) = newPixelArray(i - 1, j) / 2;
            }
        else
            for (int j = 0; j < newWidth; ++j) {
                newPixelArray(i, j) = newPixelArray(i - 1, j) / 2 + newPixelArray(i + 1, j) / 2;
            }
    }
    return {newPixelArray};
}

BMPImage textImg(const std::u16string &str, Font *font, uint8_t scale, Pixel background_color, Pixel font_color) {
    auto strSize = str.size();
    uint32_t glyphHeight = font->glyphHeight;
    uint32_t glyphWidth = font->glyphWidth;
    uint32_t imgWidth = strSize * glyphWidth * scale;
    uint32_t imgHeight = glyphHeight * scale;
    PixelArray pixels(imgWidth, imgHeight);
    for (int i = 0; i < strSize; ++i) {
        auto glyph = font->_glyphs[str[i]];
        for (int j = 0; j < glyphHeight * scale; ++j) {
            for (int l = 0; l < glyphWidth * scale; ++l) {
                if (glyph->glyph[j / scale][l / scale])
                    pixels(j, glyphWidth * scale * i + l) = font_color;
                else
                    pixels(j, glyphWidth * scale * i + l) = background_color;
            }
        }
    }

    return {pixels};
}

BMPImage upscale1_5x_ver2(BMPImage &img) {
    auto oldPixels = img.pixels();
    const uint32_t newHeight = img.height() * 3 / 2;
    const uint32_t newWidth = img.width() * 3 / 2;
    PixelArray newPixelArray(newWidth, newHeight);
    for (int i = 0; i < newHeight; ++i) {
        int oldi = std::round(i * 2 / 3.);
        if ((i + 1) % 3 == 0) {
            if (i == newHeight - 1)
                newPixelArray(i, 0) = oldPixels(oldi, 0) / 2;
            else {
                newPixelArray(i, 0) = oldPixels(oldi, 0) / 2 + oldPixels(oldi + 1, 0) / 2;
            }
            continue;
        }
        for (int j = 0; j < newWidth; ++j) {
            int oldj = std::round(j * 2 / 3.);
            if ((j + 1) % 3 != 0)
                newPixelArray(i, j) = oldPixels(oldi, oldj);
            else if (j == newWidth - 1)
                newPixelArray(i, j) = oldPixels(oldi, oldj) / 2;
            else
                newPixelArray(i, j) = oldPixels(oldi, oldj) / 2 + oldPixels(oldi, oldj + 1) / 2;
        }
    }
    for (int i = 2; i < newHeight; i += 3) {
        if (i == newHeight - 1)
            for (int j = 0; j < newWidth; ++j) {
                newPixelArray(i, j) = newPixelArray(i - 1, j) / 2;
            }
        else
            for (int j = 1; j < newWidth; ++j) {
                if (j == newWidth - 1) {
                    newPixelArray(i, j) = newPixelArray(i, j - 1) / 2;
                    continue;
                }
                auto f00 = newPixelArray(i - 1, j - 1);
                auto f10 = newPixelArray(i - 1, j + 1);
                auto f01 = newPixelArray(i + 1, j - 1);
                auto f11 = newPixelArray(i + 1, j + 1);
                newPixelArray(i, j) = f10 / 4 + f00 / 4 + f01 / 4 + f11 / 4;
            }
    }
    return {newPixelArray};
}

BMPImage upscale2x_ver2(BMPImage &img) {
    auto oldPixels = img.pixels();
    const uint32_t newHeight = img.height() * 2;
    const uint32_t newWidth = img.width() * 2;
    PixelArray newPixelArray(newWidth, newHeight);
    for (int i = 0; i < newHeight; ++i) {
        if ((i + 1) % 2 == 0) {
            if (i == newHeight - 1)
                newPixelArray(i, 0) = oldPixels(i / 2, 0) / 2;
            else
                newPixelArray(i, 0) = oldPixels(i / 2, 0) / 2 + oldPixels(i / 2 + 1, 0) / 2;
            continue;
        }
        for (int j = 0; j < newWidth; ++j) {
            if (j % 2 == 0)
                newPixelArray(i, j) = oldPixels(i / 2, j / 2);
            else if (j == newWidth - 1)
                newPixelArray(i, j) = oldPixels(i / 2, j / 2) / 2;
            else
                newPixelArray(i, j) = oldPixels(i / 2, j / 2) / 2 + oldPixels(i / 2, j / 2 + 1) / 2;
        }
    }
    for (int i = 1; i < newHeight; i += 2) {
        if (i == newHeight - 1)
            for (int j = 1; j < newWidth; ++j) {
                newPixelArray(i, j) = newPixelArray(i - 1, j) / 2;
            }
        else
            for (int j = 1; j < newWidth; ++j) {
                if (j == newWidth - 1) {
                    newPixelArray(i, j) = newPixelArray(i, j - 1) / 2;
                    continue;
                }
                auto f00 = newPixelArray(i - 1, j - 1);
                auto f10 = newPixelArray(i - 1, j + 1);
                auto f01 = newPixelArray(i + 1, j - 1);
                auto f11 = newPixelArray(i + 1, j + 1);
                newPixelArray(i, j) = f10 / 4 + f00 / 4 + f01 / 4 + f11 / 4;
            }
    }
    return {newPixelArray};
}