#include<stdio.h>
#include<string.h>

int get_riff(FILE *fp_in,FILE *fp_out, size_t riff_size, size_t shoc_size);
int get_size(FILE *fp_in);
char * get_form(FILE *fp_in);
char * get_filename(char *form);

int main() {

    char *form;
    char *filename;

    size_t counter=0;
    size_t size;
    size_t position;
    size_t file_size;
    size_t riff_size;

    printf("\nFuture Cop RIFF extractor - v0.16\n\n");

    printf("Opening file Mp\n\n");
        FILE *fp_in;
        fp_in = fopen("Mp", "rb");
        fseek(fp_in, 0, SEEK_END);
        file_size = ftell(fp_in);
        fseek(fp_in, 0, SEEK_SET);
        FILE *fp_out;

    //loop start

    while(position != file_size)
    {
        form = get_form(fp_in);
        size = get_size(fp_in);

        //print chunk info
        printf("ID: %u\n", counter);
        printf("Form: %s\n", form);
        printf("Size: %u bytes\n\n",size);

        fseek(fp_in, -8, SEEK_CUR);

        //check if fourcc is SHOC
        if (strstr (form,"SHOC") != 0)
        {
            //if fourcc was SHOC, jump 20 bytes ahead
            fseek(fp_in, 20, SEEK_CUR);
            form = get_form(fp_in);

            //check if fourcc is RIFF
            if (strstr (form,"FFIR") != 0)
            {
                riff_size = get_size(fp_in);
                printf("RIFF gefunden!\n");
                printf("RIFF size: %u bytes\n\n",riff_size);

                fseek(fp_in, -8, SEEK_CUR);                 // zu RIFF fourcc zurueck spulen
                filename = get_filename(form);
                fp_out = fopen(filename,"w");
                get_riff(fp_in, fp_out, riff_size, size);
                fclose(fp_out);
            }
                //printf("Press ENTER to continue");
                //getchar();
            else
            {
                fseek(fp_in, -24, SEEK_CUR);
                fseek(fp_in, size, SEEK_CUR);
            }
        }
        else
        {
            fseek(fp_in, size, SEEK_CUR);
        }
        counter++;
        position = ftell(fp_in);
    }

    fclose(fp_in);
    return 0;
}

char * get_filename(char *form)
{
    static char filename[30];
    static size_t riff_counter;

    if (strcmp(form,"FFIR")==0)
    {
        snprintf(filename, 10, "%d", riff_counter);
        strcat(filename, ".wav");
        riff_counter++;
        return filename;
    }
}

int get_riff(FILE *fp_in, FILE *fp_out, size_t riff_size, size_t shoc_size)
{
    int x;
    char buffer;

    shoc_size = shoc_size-20;

            for (x=0; x < shoc_size; x++)
            {
                fread(&buffer, 1, 1, fp_in);
                fwrite(&buffer, 1, 1, fp_out);
                riff_size--;
            }

            while (riff_size > 0)
            {
                fseek(fp_in, 4, SEEK_CUR);
                shoc_size = get_size(fp_in);
                fseek(fp_in, 12, SEEK_CUR);
                shoc_size = shoc_size-20;

                for (x=0; x < shoc_size; x++)
                {
                    fread(&buffer, 1, 1, fp_in);
                    fwrite(&buffer, 1, 1, fp_out);
                    if(riff_size > 0){
                        riff_size--;
                    }
                }
            }
            printf("RIFF complete!\n\n");
}

int get_size( FILE *fp_in)
{
    size_t size=0;
    fread(&size, 1, 4, fp_in);
    return size;
}

char * get_form( FILE *fp_in)
{
    static int endian = 0;

    static char fourcc[sizeof "XXXX"];
        fourcc[0]=48;
        fourcc[1]=48;
        fourcc[2]=48;
        fourcc[3]=48;
        fourcc[4]='\0';

    //read fourcc

    switch(endian)
    {
        case 0:
            fread(&fourcc[0], 1, 1, fp_in);
            fread(&fourcc[1], 1, 1, fp_in);
            fread(&fourcc[2], 1, 1, fp_in);
            fread(&fourcc[3], 1, 1, fp_in);

            if (strstr (fourcc,"CTRL") != 0)
            {
                endian=1;
            }

            if (strstr (fourcc,"LRTC") != 0)
            {
                endian=2;
            }
        break;

        case 1:
            fread(&fourcc[0], 1, 1, fp_in);
            fread(&fourcc[1], 1, 1, fp_in);
            fread(&fourcc[2], 1, 1, fp_in);
            fread(&fourcc[3], 1, 1, fp_in);
        break;

        case 2:
            fread(&fourcc[3], 1, 1, fp_in);
            fread(&fourcc[2], 1, 1, fp_in);
            fread(&fourcc[1], 1, 1, fp_in);
            fread(&fourcc[0], 1, 1, fp_in);
        break;
    }

    return fourcc;
}