resize(less)/pset4/cs50

// Copies a BMP file

#include <stdio.h>
#include <stdlib.h>

#include "bmp.h"

int main(int argc, char *argv[])
{
    // ensure proper usage
    if (argc != 4)
    {
        fprintf(stderr, "Usage: copy infile outfile\n");
        return 1;
    }

    // ensure 'n' is between 0 and 100
    int num;
    if (atoi(argv[1]) > 0 && atoi(argv[1]) <= 100)
    {
        num = atoi(argv[1]);
    }
    else
    {
        return 1;
    }

    // remember filenames
    int n = num;
    char *infile = argv[2];
    char *outfile = argv[3];

    // open input file
    FILE *inptr = fopen(infile, "r");
    if (inptr == NULL)
    {
        fprintf(stderr, "Could not open %s.\n", infile);
        return 2;
    }

    // open output file
    FILE *outptr = fopen(outfile, "w");
    if (outptr == NULL)
    {
        fclose(inptr);
        fprintf(stderr, "Could not create %s.\n", outfile);
        return 3;
    }

    // read infile's BITMAPFILEHEADER
    BITMAPFILEHEADER bf;
    fread(&bf, sizeof(BITMAPFILEHEADER), 1, inptr);
    BITMAPFILEHEADER bfNew; //new
    bfNew = bf; //now fread's data is workable from bfNew

    // read infile's BITMAPINFOHEADER
    BITMAPINFOHEADER bi;
    fread(&bi, sizeof(BITMAPINFOHEADER), 1, inptr);
    BITMAPINFOHEADER biNew;
    biNew = bi; //now fread's data is workable from biNew

    // ensure infile is (likely) a 24-bit uncompressed BMP 4.0
    if (bf.bfType != 0x4d42 || bf.bfOffBits != 54 || bi.biSize != 40 ||
        bi.biBitCount != 24 || bi.biCompression != 0)
    {
        fclose(outptr);
        fclose(inptr);
        fprintf(stderr, "Unsupported file format.\n");
        return 4;
    }


    // updated height & width
    biNew.biWidth = bi.biWidth * n;
    biNew.biHeight = bi.biHeight * n;

    // determine padding for scanlines
    int padding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
    int paddingNew = (4 - (biNew.biWidth * sizeof(RGBTRIPLE)) % 4) % 4; //new padding

    // update dimension
    biNew.biSizeImage = ((sizeof(RGBTRIPLE) * biNew.biWidth) + paddingNew) * abs(biNew.biHeight);
    bfNew.bfSize = biNew.biSizeImage + sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);

    // write outfile's BITMAPFILEHEADER
    fwrite(&bfNew, sizeof(BITMAPFILEHEADER), 1, outptr);

    // write outfile's BITMAPINFOHEADER
    fwrite(&biNew, sizeof(BITMAPINFOHEADER), 1, outptr);


    /*
    //RE-COPY METHOD
    // iterate over each scanline
    for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
    {
        //FIRST TIME
        // for n-1 times
        for (int a = 0; a < n - 1; a++)
        {
            //read, write, padding, cursor_BACK
            //iterate over each pixel
            for (int b = 0; b < bi.biWidth; b++)
            {
                // temporary storage
                RGBTRIPLE triple;

                // read RGB triple from infile
                fread(&triple, sizeof(RGBTRIPLE), 1, inptr);

                //// for n-times
                // write RGB triple to outfile
                for (int c = 0; c < n; c++)
                {
                    fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);
                }
                //fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);

                // write new padding
                for (int k = 0; k < paddingNew; k++)
                {
                    fputc(0x00, outptr);
                }

                // send infile cursor back
                fseek(inptr, -(bi.biWidth * sizeof(RGBTRIPLE)), SEEK_CUR);
            }
        }


        //LAST TIME
        //read, write, padding, padding_SKIP
        // iterate over pixels in scanline
        for (int j = 0; j < bi.biWidth; j++)
        {
            // temporary storage
            RGBTRIPLE triple;

            // read RGB triple from infile
            fread(&triple, sizeof(RGBTRIPLE), 1, inptr);

            // write RGB trip to outfile
            fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);

            // write new padding
            for (int k = 0; k < paddingNew; k++)
            {
                fputc(0x00, outptr);
            }

            // skip over padding, if any (infile)
            fseek(inptr, padding, SEEK_CUR);
        }
    }
    */



    //REWRITE METHOD
    // iterate over infile's scanlines
    for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
    {
        // temporary storage
        RGBTRIPLE pixelArr[abs(biNew.biWidth)]; //RGBTRIPLE pixelArr[abs(biNew.biWidth) * sizeof(RGBTRIPLE)];
        // Array index counter
        int count = 0;

        // iterate over pixels in scanline
        for (int j = 0; j < bi.biWidth; j++)
        {
            //make an array, fill up and at the end of this loop send values to upper loop
            // temporary storage
            RGBTRIPLE triple;
            //RGBTRIPLE pixelArr[n];

            // read RGB triple from infile
            fread(&triple, sizeof(RGBTRIPLE), 1, inptr);

            // write pixel in array n times
            for (int l = 0; l < n; l++, count++)
            {
                pixelArr[count] = triple;
            }
        }

        // for n times scanline
        for (int m = 0; m < n; m++) //for (int m = 0; m < n; m++)
        {
            // write RGB triple array to outfile
            fwrite(&pixelArr, sizeof(biNew.biWidth), 1, outptr);

            // write new padding
            for (int k = 0; k < paddingNew; k++)
            {
                fputc(0x00, outptr);
            }
        }

        // skip over padding, if any
        fseek(inptr, padding, SEEK_CUR);

        // fseek?
    }


    // close infile
    fclose(inptr);

    // close outfile
    fclose(outptr);

    // success
    return 0;
}