#include "PikaCV_Transforms.h"
#include "PikaCV_Converter.h"
#include "PikaCV_Filter.h"
#include "PikaCV_common.h"
#include "math.h"

void PikaCV_Transforms_rotateDown(PikaObj* self, PikaObj* image) {
    PikaCV_Image* img = obj_getStruct(image, "image");
    if (NULL == img) {
        pika_assert(0);
        return;
    }
    if ((img->format != PikaCV_ImageFormat_Type_BGR888) &&
        (img->format != PikaCV_ImageFormat_Type_RGB888)) {
        obj_setErrorCode(self, PIKA_RES_ERR_OPERATION_FAILED);
        __platform_printf("unsupported image format\n");
        return;
    }
    int width = img->width;
    int height = img->height;
    int size_new = width * height * 3;
    Arg* arg_data_new = arg_setBytes(NULL, "", NULL, size_new);
    uint8_t* data = _image_getData(image);
    uint8_t* data_new = arg_getBytes(arg_data_new);
    int i, j, k;
    /* rotate */
    for (i = 0; i < height; i++) {
        for (j = 0; j < width; j++) {
            for (k = 0; k < 3; k++) {
                data_new[(height - i - 1) * width * 3 + j * 3 + k] =
                    data[i * width * 3 + j * 3 + k];
            }
        }
    }
    obj_setBytes(image, "_data", data_new, size_new);
    img->size = size_new;
    arg_deinit(arg_data_new);
}

void PikaCV_Transforms_threshold(PikaObj* self,
                                 PikaObj* image,
                                 int maxval,
                                 int thre,
                                 int thresholdType) {
    PikaCV_Image* src = obj_getStruct(image, "image");

    if (NULL == src) {
        pika_assert(0);
        return;
    }
    PikaCV_Format_Check(image, PikaCV_ImageFormat_Type_GRAY,
                        PikaCV_Check_Converter);
    uint8_t* src_data = _image_getData(image);

    int i;
    if (thresholdType == 0) {
        for (i = 0; i < (src->size); i++) {
            src_data[i] = src_data[i] > thre ? maxval : 0;
        }
    } else if (thresholdType == 1) {
        for (i = 0; i < (src->size); i++) {
            src_data[i] = src_data[i] > thre ? 0 : maxval;
        }
    } else if (thresholdType == 2) {
        for (i = 0; i < (src->size); i++) {
            src_data[i] = src_data[i] > thre ? thre : src_data[i];
        }
    } else if (thresholdType == 3) {
        for (i = 0; i < (src->size); i++) {
            src_data[i] = src_data[i] > thre ? src_data[i] : 0;
        }
    } else if (thresholdType == 4) {
        for (i = 0; i < (src->size); i++) {
            src_data[i] = src_data[i] > thre ? 0 : src_data[i];
        }
    } else if (thresholdType == 5) {
        PikaCV_Transforms_setOTSU(self, image);
    } else {
        pika_assert(0);
        return;
    }

    obj_setBytes(image, "_data", src_data, src->size);
}

void PikaCV_Transforms_setROI(PikaObj* self,
                              PikaObj* image,
                              int x,
                              int y,
                              int w,
                              int h) {
    PikaCV_Image* src = obj_getStruct(image, "image");
    int width = src->width;
    int height = src->height;

    if (NULL == src) {
        pika_assert(0);
        return;
    }
    PikaCV_Format_Check(image, PikaCV_ImageFormat_Type_RGB888,
                        PikaCV_Check_Converter);
    if (x <= 0 || y <= 0 || w <= 0 || h <= 0) {
        pika_assert(0);
        return;
    }
    if (x + w > width || y + h > height) {
        pika_assert(0);
        return;
    }

    int size_new = h * w * 3;
    Arg* arg_data_new = arg_setBytes(NULL, "", NULL, size_new);
    uint8_t* data = _image_getData(image);
    uint8_t* data_new = arg_getBytes(arg_data_new);

    for (int i = 0; i < h; i++) {
        for (int j = 0; j < w; j++) {
            data_new[i * 3 * w + j * 3] =
                data[(i + y - 1) * width * 3 + (j + x - 1) * 3];
            data_new[i * 3 * w + j * 3 + 1] =
                data[(i + y - 1) * width * 3 + (j + x - 1) * 3 + 1];
            data_new[i * 3 * w + j * 3 + 2] =
                data[(i + y - 1) * width * 3 + (j + x - 1) * 3 + 2];
        }
    }
    src->height = h;
    src->width = w;
    src->size = size_new;

    obj_setBytes(image, "_data", data_new, size_new);
    arg_deinit(arg_data_new);
}

int PikaCV_Transforms_getOTSUthre(PikaObj* self, PikaObj* image) {
    PikaCV_Image* src = obj_getStruct(image, "image");

    if (NULL == src) {
        pika_assert(0);
        return 0;
    }
    PikaCV_Format_Check(image, PikaCV_ImageFormat_Type_GRAY,
                        PikaCV_Check_Converter);
    const int Grayscale = 256;
    int width = src->width;
    int height = src->height;
    int size = src->size;
    int threshold = 0;
    int graynum[256] = {0};
    uint8_t* data = _image_getData(image);
    for (int i = 0; i < size; i++) {
        graynum[data[i]]++;
    }

    pika_float P[256] = {0.0};
    pika_float PK[256] = {0.0};
    pika_float MK[256] = {0.0};
    pika_float srcpixnum = width * height, sumtmpPK = 0, sumtmpMK = 0;
    for (int i = 0; i < Grayscale; ++i) {
        P[i] = graynum[i] / srcpixnum;
        PK[i] = sumtmpPK + P[i];
        sumtmpPK = PK[i];
        MK[i] = sumtmpMK + i * P[i];
        sumtmpMK = MK[i];
    }

    pika_float Var = 0;
    for (int k = 0; k < Grayscale; ++k) {
        if (PK[k] > 0.0) {
            pika_float t = MK[Grayscale - 1] * PK[k] - MK[k];
            pika_float w = PK[k] * (1 - PK[k]);
            pika_float variance = t * t / w;
            if (variance > Var) {
                Var = variance;
                threshold = k;
            }
        }
    }

    return threshold;
}

void PikaCV_Transforms_setOTSU(PikaObj* self, PikaObj* image) {
    PikaCV_Image* src = obj_getStruct(image, "image");

    if (NULL == src) {
        pika_assert(0);
        return;
    }
    PikaCV_Format_Check(image, PikaCV_ImageFormat_Type_GRAY,
                        PikaCV_Check_Converter);
    int thre = PikaCV_Transforms_getOTSUthre(self, image);
    uint8_t* src_data = _image_getData(image);

    int i;
    for (i = 0; i < (src->size); i++) {
        src_data[i] = src_data[i] > thre ? 255 : 0;
    }

    obj_setBytes(image, "_data", src_data, src->size);
}

#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))

void PikaCV_Transforms_resize(PikaObj* self,
                              PikaObj* image,
                              int x,
                              int y,
                              int resizeType) {
    PikaCV_Image* src = obj_getStruct(image, "image");
    int width = src->width;
    int height = src->height;
    if (NULL == src) {
        pika_assert(0);
        return;
    }
    if (x <= 0 || y <= 0) {
        pika_assert(0);
        return;
    }
    PikaCV_Format_Check(image, PikaCV_ImageFormat_Type_RGB888,
                        PikaCV_Check_Converter);

    int size_new = x * y * 3;
    Arg* arg_data_new = arg_setBytes(NULL, "", NULL, size_new);
    uint8_t* data = _image_getData(image);
    uint8_t* data_new = arg_getBytes(arg_data_new);

    pika_float scale_x = (pika_float)width / (pika_float)x;
    pika_float scale_y = (pika_float)height / (pika_float)y;
    if (resizeType == 0) {
        for (int i = 0; i < y; ++i) {
            int sy = floor(i * scale_y);
            sy = MIN(sy, (height - 1));
            for (int j = 0; j < x; ++j) {
                int sx = floor(j * scale_x);
                sx = MIN(sx, (width - 1));

                data_new[i * x * 3 + j * 3] = data[sy * width * 3 + sx * 3];
                data_new[i * x * 3 + j * 3 + 1] =
                    data[sy * width * 3 + sx * 3 + 1];
                data_new[i * x * 3 + j * 3 + 2] =
                    data[sy * width * 3 + sx * 3 + 2];
            }
        }
    } else {
        pika_assert(0);
        return;
    }
    src->height = y;
    src->width = x;
    src->size = size_new;

    obj_setBytes(image, "_data", data_new, size_new);
    arg_deinit(arg_data_new);
}

void PikaCV_Transforms_adaptiveThreshold(PikaObj* self,
                                         PikaObj* image,
                                         int maxval,
                                         int subsize,
                                         int c,
                                         int method) {
    PikaCV_Image* src = obj_getStruct(image, "image");

    if (NULL == src) {
        pika_assert(0);
        return;
    }
    if (c < 0 || c > 255) {
        pika_assert(0);
        return;
    }
    PikaCV_Format_Check(image, PikaCV_ImageFormat_Type_GRAY,
                        PikaCV_Check_Converter);
    int size = src->size;
    uint8_t* src_data = _image_getData(image);
    uint8_t* src_copy;
    src_copy = (uint8_t*)calloc(size, 1);

    memcpy(src_copy, src_data, size);

    if (method == 0) {
        PikaCV_Filter_meanFilter(self, image, subsize, subsize);  //均值滤波
    } else if (method == 1) {
        PikaCV_Filter_medianFilter(self, image);  //中值滤波
    } else {
        free(src_copy);
        return;
    }

    /* update size after filter */
    size = src->size;
    uint8_t* smooth_data = _image_getData(image);
    for (int i = 0; i < size; i++) {
        uint8_t result = smooth_data[i] - (uint8_t)c;
        smooth_data[i] =
            ((result < MIN(smooth_data[i], (uint8_t)c)) ? 0 : result);
    }
    for (int i = 0; i < size; i++) {
        src_copy[i] = ((src_copy[i] > smooth_data[i]) ? (uint8_t)maxval : 0);
    }

    obj_setBytes(image, "_data", src_copy, size);
    free(src_copy);
}

#undef MAX
#undef MIN