#include "tricorn_V1.h"
#include "color_table.h"
#include "converge_helper.h"


/**
 * @brief Generates a Tricorn fractal image using an optimized scalar implementation.
 * @param start The starting complex coordinate (bottom-left or top-left depending on height sign).
 * @param width The width of the target image in pixels.
 * @param height The height of the target image. A negative height reverses the Y-axis calculation.
 * @param res The step size (resolution) per pixel in the complex plane.
 * @param n The maximum number of mathematical iterations per pixel.
 * @param color If true, generates a 24-bit RGB image. If false, writes a grayscale image.
 * @param img Pointer to the pre-allocated memory buffer where the bitmap data will be stored.
 */
void tricorn_V1(float complex start, size_t width, ssize_t height, float res, unsigned n, _Bool color, unsigned char* img){
    int bytesPerColor = color ? 3 : 1;
    
    // Absolute height for iteration purposes
    ssize_t actual_height = height > 0 ?  height : (ssize_t)(-height);

    // Depending on the sign of height we generate the image top-down or bottom up
    // As we iterate from the top always, if it is negative we would have to start at the end of the imaginary part and go in the oposite direction when generating
    ssize_t imag_direction = height < 0 ? -1 : 1;
    float c_start_real = creal(start);
    float c_start_imag = height > 0 ? cimag(start) : cimag(start) + ((actual_height-1) * res);


    float vertical_step = imag_direction * res;
    size_t position = 0; // Start value for the position in the image buffer. Will be accumulated later


    float c_imag = c_start_imag; // Start value for the imaginary part, which will be accumulated
    for(ssize_t y = 0; y < actual_height; y++){
        float c_real = c_start_real;
        for(size_t x = 0; x < width; x++){
            unsigned value = converge(c_real,c_imag,n);

            if(!color){ // Grayscale colors as specified by the assignment r = g = b
                img[position] =  value;
            }
            else{ // Temporary colors with random multipliers
                img[position] = color_lookup_table[value][0];
                img[position + 1] = color_lookup_table[value][1];
                img[position + 2] = color_lookup_table[value][2];
            }

            position += bytesPerColor; // Caculate position for next pixel
            c_real += res; // Calculate real part for next pixel
        }
        c_imag += vertical_step; // For reach row calculate the next value for the imaginary part by accumulation
    }
}