#include "Image.h"
#include <stdlib.h>
#include <assert.h>
#include <stdio.h>

/* Function to create a new image */
Image *NewImage(unsigned int Width, unsigned int Height) {
    // Allocate memory for the main Image struct
    Image *image = malloc(sizeof(Image));
    
    // Check if malloc worked
    if (image == NULL) {
        return NULL;
    }

    // Set the width and height
    image->W = Width;
    image->H = Height;

    // Allocate memory for Red, Green, and Blue arrays
    // Each one needs Width * Height amount of space
    image->R = malloc(sizeof(unsigned char) * Width * Height);
    image->G = malloc(sizeof(unsigned char) * Width * Height);
    image->B = malloc(sizeof(unsigned char) * Width * Height);

    // If any of the color arrays failed, we need to clean up and exit
    if (image->R == NULL || image->G == NULL || image->B == NULL) {
        DeleteImage(image);
        return NULL;
    }

    return image;
}

/* Function to free all the memory we used */
void DeleteImage(Image *image) {
    // Make sure the image actually exists before freeing
    if (image != NULL) {
        // Free the color arrays first
        if (image->R != NULL) {
            free(image->R);
        }
        if (image->G != NULL) {
            free(image->G);
        }
        if (image->B != NULL) {
            free(image->B);
        }

        // Set pointers to NULL so we don't use them by accident
        // (This is required for the assignment)
        image->R = NULL;
        image->G = NULL;
        image->B = NULL;

        // Finally free the image struct itself
        free(image);
    }
}

/* Get and Set functions for RED */
unsigned char GetPixelR(const Image *image, unsigned int x, unsigned int y) {
    assert(image != NULL);
    assert(x < image->W);
    assert(y < image->H);
    // Formula for 1D index: x + (y * Width)
    int index = x + (y * image->W);
    return image->R[index];
}

void SetPixelR(Image *image, unsigned int x, unsigned int y, unsigned char r) {
    assert(image != NULL);
    assert(x < image->W);
    assert(y < image->H);
    int index = x + (y * image->W);
    image->R[index] = r;
}

/* Get and Set functions for GREEN */
unsigned char GetPixelG(const Image *image, unsigned int x, unsigned int y) {
    assert(image != NULL);
    assert(x < image->W);
    assert(y < image->H);
    int index = x + (y * image->W);
    return image->G[index];
}

void SetPixelG(Image *image, unsigned int x, unsigned int y, unsigned char g) {
    assert(image != NULL);
    assert(x < image->W);
    assert(y < image->H);
    int index = x + (y * image->W);
    image->G[index] = g;
}

/* Get and Set functions for BLUE */
unsigned char GetPixelB(const Image *image, unsigned int x, unsigned int y) {
    assert(image != NULL);
    assert(x < image->W);
    assert(y < image->H);
    int index = x + (y * image->W);
    return image->B[index];
}

void SetPixelB(Image *image, unsigned int x, unsigned int y, unsigned char b) {
    assert(image != NULL);
    assert(x < image->W);
    assert(y < image->H);
    int index = x + (y * image->W);
    image->B[index] = b;
}

/* Functions to get Width and Height */
unsigned int ImageWidth(const Image *image) {
    assert(image != NULL);
    return image->W;
}

unsigned int ImageHeight(const Image *image) {
    assert(image != NULL);
    return image->H;
}