#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "imageInput.h"

#define BUFFER_SIZE 100
#define FILE_HEADER_STRING "__info2_image_file_format__"

// TODO Implementieren Sie geeignete Hilfsfunktionen für das Lesen der Bildserie aus einer Datei

void readIndividualImage(unsigned int width, unsigned int height, FILE *file, GrayScaleImage *gimage){

    GrayScalePixelType *buf = calloc(width * height, sizeof(unsigned char));
    if(!buf){
        fprintf(stderr, "calloc failed!\n");
        return;
    }
    if(fread(buf, sizeof(char), width * height,file) != (width* height)){
        fprintf(stderr, "imageline not in the rigth format!\n");
        free(buf);
        return;
    }
    gimage = calloc(sizeof(GrayScaleImage), 1);
    if(gimage == NULL){
        fprintf(stderr, "calloc failed!\n");
        free(buf);
        return;
    }
    gimage->buffer = buf;
    gimage->width = width;
    gimage->height = height;

    //fprintf(stdout, "%d,%d\n", gimage->width, gimage->height);
}

// TODO Vervollständigen Sie die Funktion readImages unter Benutzung Ihrer Hilfsfunktionen
GrayScaleImageSeries *readImages(const char *path)
{
    GrayScaleImageSeries *series = NULL;
    
    series = calloc(1, sizeof(GrayScaleImageSeries));
    if(series == NULL){
        fprintf(stderr, "Couldn't allocate enough space!\n");
        return NULL;
    }
    series->count = 0;

    FILE *file = fopen(path, "rb");
    if(file == NULL){
        fprintf(stderr, "%s could not be opened!\n", path);
        clearSeries(series);
        return NULL;
    }

    //Schaue ob die erste Zeile der richtige Header ist.
    char buffer[32];
    fread(buffer, sizeof(char), strlen(FILE_HEADER_STRING), file);
    if(strncmp(buffer, FILE_HEADER_STRING, strlen(FILE_HEADER_STRING))){
        fprintf(stderr, "__info2_image_file_format__ not found!\n");
        clearSeries(series);
        return NULL;
    }

    short shortbuffer[3];
    if(fread(shortbuffer, sizeof(short), 3, file) != 3){
        fprintf(stderr, "Couldn't read number of images/sizes of Images!\n");
        clearSeries(series);
        return NULL;
    }

    //Merke menge an Bildern und Länge und Breite der Bilder
    series->count = shortbuffer[0];
    unsigned int width = shortbuffer[1];
    unsigned int height = shortbuffer[2];
    //fprintf(stderr, "%d, %d, %d\n", series->count, width, height);

    if(width == 0 || height == 0 || series->count == 0){
        fprintf(stderr, "number of images, width or heigth are 0!\n");
        return NULL;
    }

    series->labels = calloc(series->count, sizeof(char));
    if(series->labels == NULL){
        fprintf(stderr, "calloc failed!\n");
        clearSeries(series);
        return NULL;
    }

    //Lies Bilder aus
    for (int i = 0; i < series->count; i++){
        readIndividualImage(width, height, file, &series->images[i]);
        /*if(series->images[i] == NULL){
            clearSeries(series);
            return NULL;
        }*/
        fread(&series->labels[i], sizeof(char), 1, file);
        //fprintf(stdout, "width: %d, height: %d\n", series->images[i].width, series->images[i].height);
    }
    return series;
}

// TODO Vervollständigen Sie die Funktion clearSeries, welche eine Bildserie vollständig aus dem Speicher freigibt
void clearSeries(GrayScaleImageSeries *series)
{
    
    for(int i = 0; i < series->count; i++){
        fprintf(stdout, "%d\n", i);
        free(&series->images[i].buffer);
        fprintf(stdout, "%d\n", i);
    }
    free(series->labels);
    free(series);
    return;
}