import java.awt.*;
import java.awt.event.*;
import java.io.*;
import ij.*;
import ij.io.*;
import ij.plugin.PlugIn;

//This can open the Hamamatsu photonics IMG file.
//With the modified HandleExtraFileTypes.java, Drag&Drop can be used to open the file.
//This plugin was modified from the plugin (OpenSPE_.java) to open the SPE files.
//
// Satoshi Matsuyama (Osaka Univ.)
// matsuyama@prec.eng.osaka-u.ac.jp

public class OpenIMG_ implements PlugIn {
	private static int HeaderSize=10240;	//2593;	//この値は後で正確に決める．機種によって違うみたい．final修飾子をつけたら変更不可となる
	private static int ImageWidth;
	private static int ImageHeight;
	private static int ImageByte;
	
	public void run(String arg) {
		OpenDialog od = new OpenDialog("Open IMG...", arg);
		String file = od.getFileName();
		if (file == null) return;
		String directory = od.getDirectory();
		ImagePlus imp = open(directory, file);
		if (imp != null ) {
			imp.show();
		} else {
			IJ.showMessage("Open IMG...", "Failed.");
		}
	}

	public static ImagePlus open(String directory, String file) {
		File f = new File(directory, file);
		
		try {
		//ヘッダ調べる
			FileInputStream in = new FileInputStream(f);
			byte[] h = new byte[HeaderSize];
			in.read(h, 0, h.length);
			//バイト配列を文字に変換
			String result = new String(h, "UTF-8");
			//IJ.showMessage("check", result);
			//ヘッダの特定箇所を検索して抜き出す
			int index = result.indexOf("Prop_ImageWidth=");
			index += "Prop_ImageWidth=".length();
			if (result.charAt(index+4) == '\u002C') {	//\u002Cは","を意味する
				ImageWidth=Integer.parseInt(result.substring(index,index+4));	//1000〜9999
			} else if (result.charAt(index+3) == '\u002C') {
				ImageWidth=Integer.parseInt(result.substring(index,index+3));	//100〜999
			} else if (result.charAt(index+5) == '\u002C') {
				ImageWidth=Integer.parseInt(result.substring(index,index+5));	//10000〜99999
			} else if (result.charAt(index+2) == '\u002C') {
				ImageWidth=Integer.parseInt(result.substring(index,index+2));	//10〜99
			} else {
				IJ.showMessage("Error","Incorrect width!");
			}
			//IJ.showMessage("check", "width=" + String.valueOf(ImageWidth));
			index = result.indexOf("Prop_ImageHeight=");
			index += "Prop_ImageHeight=".length();
			if (result.charAt(index+4) == '\u002C') {
				ImageHeight=Integer.parseInt(result.substring(index,index+4));	//1000〜9999
			} else if (result.charAt(index+3) == '\u002C') {
				ImageHeight=Integer.parseInt(result.substring(index,index+3));	//100〜999
			} else if (result.charAt(index+5) == '\u002C') {
				ImageHeight=Integer.parseInt(result.substring(index,index+5));	//10000〜99999
			} else if (result.charAt(index+2) == '\u002C') {
				ImageHeight=Integer.parseInt(result.substring(index,index+2));	//10〜99
			} else {
				IJ.showMessage("Error","Incorrect height!");
			}
			//IJ.showMessage("check", "height=" + String.valueOf(ImageHeight));
			index = result.indexOf("BytesPerPixel=");
			index += "BytesPerPixel=".length();
			ImageByte=Integer.parseInt(result.substring(index,index+1));
			//IJ.showMessage("check", "imagebyte=" + String.valueOf(ImageByte));
			
			//ヘッダサイズを正確に求める．CMOS,CCDによってヘッダサイズが違うみたい
			HeaderSize=(int)f.length()-ImageWidth*ImageHeight*ImageByte;	//length()で得られるのはlong型．キャストする．
			//IJ.showMessage("check", "header=" + String.valueOf(HeaderSize));
			
			//データ本体を開く
			FileInfo fi = new FileInfo();
			fi.directory = directory;
			fi.fileFormat = fi.RAW;
			fi.fileName = file;

			//1ピクセルのByte数を考慮させる
			if (ImageByte == 1) {
				fi.fileType = FileInfo.GRAY8;	//8ビット(1バイト)
			} else if (ImageByte == 2) {
				fi.fileType = FileInfo.GRAY16_UNSIGNED;	//16ビット(2バイト)，signed(符号有)，unsigned(符号無)．
			} else if (ImageByte == 4) {
				fi.fileType = FileInfo.GRAY32_UNSIGNED;	//32ビット(4バイト)，signed(符号有)，unsigned(符号無)．
			} else {
				IJ.showMessage("Error","The file cannot be opened!");
				return null;
			}

			fi.gapBetweenImages = 0;
			fi.height = ImageHeight;
			fi.intelByteOrder = true;	//これ大事．最下位の桁から順番に数字が格納されているという意味．img，speともにtrueでOK．
			fi.nImages = 1;	//画像の数，2以上はスタックになると思われる
			fi.offset = HeaderSize;	//ヘッダの数，バイト単位．この部分を飛ばしてくれる．
			fi.width = ImageWidth;
			
			FileOpener fo = new FileOpener(fi);
			ImagePlus imp = fo.open(false);
			IJ.showStatus("");
			return imp;
			
		} catch (IOException e) {
			IJ.error("An error occured reading the file.\n \n" + e);
			IJ.showStatus("");
			return null;
		}
	}
}