package org.sadun.util.polling.pollmanagers;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.sadun.util.polling.BasePollerEvent;
import org.sadun.util.polling.CycleEndEvent;
import org.sadun.util.polling.CycleStartEvent;
import org.sadun.util.polling.DirectoryLookupEndEvent;
import org.sadun.util.polling.DirectoryLookupStartEvent;
import org.sadun.util.polling.FileFoundEvent;
import org.sadun.util.polling.FileSetFoundEvent;

import com.deltax.util.TimeInterval;

/**
 * 
 * 
 * @author Cristiano Sadun
 */
public class FileHistoryPollManager extends HistoryPollManager {

    private File file;
    private PrintWriter writer;
    private SimpleDateFormat sdf;
    private boolean firstWrite;
    private long startTime=-1;

    public FileHistoryPollManager() throws IOException {
        this(new File(".", "pollmanager.journal.txt"));
    }

    public FileHistoryPollManager(File file) throws IOException {
        this.file = file;
        this.sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss:SSS");
    }

    private void open() throws IOException {
        try {
            writer = new PrintWriter(new BufferedWriter(new FileWriter(file,false)));
        } catch (IOException e) {
            writer = null;
            throw e;
        } finally {
            firstWrite=true;
        }
    }

    protected void storeAutomoveException(Exception e, File target) {
        assert "delete".equals(e.getMessage()) || "move".equals(e.getMessage());
        boolean isDelete = "delete".equals(e.getMessage());
        try {

            log("FAILURE: "+e.getMessage()
                    + " operation failed for file " + target.getCanonicalPath());
        } catch (IOException e1) {
            log("FAILURE: "+e.getMessage()
                    + " operation failed for file " + target.getAbsolutePath());
        }
    }

    protected void storeEvent(BasePollerEvent evt) {
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw);
        boolean interesting = false;
        
        if (startTime==-1 && evt instanceof CycleStartEvent) 
            startTime=evt.getTime();

        pw.print(sdf.format(new Date(evt.getTime())) + "\t(" + TimeInterval.describe(evt.getTime()-startTime)
                + ")\t" + evt.getPoller().getName() + "\t");
        if (evt.getPoller().isSendSingleFileEvent()) {
            // Ignore file set found
            if (evt instanceof FileFoundEvent) {
                pw.print("Found file: ["
                        + ((FileFoundEvent) evt).getFile().getName());
            	pw.print("]");
            	interesting = true;
            }
        } else {
            if (evt instanceof FileSetFoundEvent) {
                try {
                    pw.println("Found files in "+((FileSetFoundEvent)evt).getDirectory().getCanonicalPath()+": [");
                } catch (IOException e1) {
                    pw.println("Found files in "+((FileSetFoundEvent)evt).getDirectory().getAbsolutePath()+": [");
                }
                File[] files = ((FileSetFoundEvent) evt).getFiles();
                for (int i = 0; i < files.length; i++) {
                    pw.println("  "+files[i].getName());
                }
                pw.print("]");
                interesting = true;
            }
        }
        if (evt instanceof DirectoryLookupStartEvent)
            try {
                pw.print("Looking up ["
                        + ((DirectoryLookupStartEvent) evt).getDirectory()
                                .getCanonicalPath() + "]");
            } catch (IOException e) {
                pw.print("Looking up ["
                        + ((DirectoryLookupStartEvent) evt).getDirectory()
                                .getAbsolutePath() + "]");
            } finally {
                interesting = true;
            }

        if (evt instanceof DirectoryLookupEndEvent)
            try {
                pw.print("Finished looking up ["
                        + ((DirectoryLookupEndEvent) evt).getDirectory()
                                .getCanonicalPath() + "]");
            } catch (IOException e) {
                pw.print("Finished looking up ["
                        + ((DirectoryLookupEndEvent) evt).getDirectory()
                                .getAbsolutePath() + "]");
            } finally {
                interesting = true;
            }
        if (evt instanceof CycleEndEvent) newLine();

        if (interesting)
            log(sw.toString());
    }

    /**
     * 
     */
    private synchronized void newLine() {
        log(System.getProperty("line.separator"), false);
        
    }

    /**
     * @param info
     * @param string
     */
    private synchronized void log(String msg) {
        log(msg,true);
    }
    
    private synchronized void log(String msg, boolean considerFirstWrite) {
        if (writer == null)
            try {
                open();
            } catch (IOException e1) {
                e1.printStackTrace();
                return;
            }
        if (considerFirstWrite) {
	        if (!firstWrite) {
	            writer.println();
	        } else firstWrite=false;
        }
        writer.print(msg);
        writer.flush();
        if (writer.checkError()) {
            try {
                open();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

}