package imageinspector.readers;

import imageinspector.data.Metadata;

public class BMPMetadataReader implements MetadataReader {

    private byte[] b;
    private int height;
    private int width;
    private StringBuilder sb;
    private int bpp;
    private Metadata metadata;

    public BMPMetadataReader(byte[] b) {
        this.b = b;
        read(b);
    }

    @Override
    public void read(byte[] b) {
        getWidth();
        getHeight();
        getBpp();
        /*OUTPUT*/
        System.out.println("Type: .BMP");
        System.out.println("Width: " + width + " pixels");
        System.out.println("Height: " + height + " pixels");
        System.out.println("Bits per pixel: " + bpp);
        metadata = new Metadata(width, height, bpp);
    }

    private void getWidth() {
        String w1, w2;
        sb = new StringBuilder();
        for (int i = 18; i < 19; i++) {
            sb.append(Integer.toHexString(b[i]));
        }
        if (sb.length() > 3) {
            w1 = sb.substring(6, sb.length());
        } else {
            w1 = sb.toString();
        }
        sb = new StringBuilder();
        for (int i = 19; i < 20; i++) {
            sb.append(Integer.toHexString(b[i]));
        }
        if (sb.length() > 3) {
            w2 = sb.substring(6, sb.length());
        } else {
            w2 = sb.toString();
        }
        String w3 = w2 + w1;
        width = (int) Long.parseLong(w3, 16);
    }

    private void getHeight() {
        String h1, h2;
        sb = new StringBuilder();
        for (int i = 22; i < 23; i++) {
            sb.append(Integer.toHexString(b[i]));
        }
        if (sb.length() > 3) {
            h1 = sb.substring(6, sb.length());
        } else {
            h1 = sb.toString();
        }
        sb = new StringBuilder();
        for (int i = 23; i < 24; i++) {
            sb.append(Integer.toHexString(b[i]));
        }
        if (sb.length() > 3) {
            h2 = sb.substring(6, sb.length());
        } else {
            h2 = sb.toString();
        }
        String h3 = h2 + h1;
        height = (int) Long.parseLong(h3, 16);
    }

    private void getBpp() {
        sb = new StringBuilder();
        for (int i = 28; i < 29; i++) {
            sb.append(Integer.toHexString(b[i]));
        }
        String b1 = sb.toString();
        sb = new StringBuilder();
        for (int i = 29; i < 30; i++) {
            sb.append(Integer.toHexString(b[i]));
        }
        String b2 = sb.toString();
        String b3 = b2 + b1;
        bpp = (int) Long.parseLong(b3, 16);
    }

}