/*******************************************************************************
 *
 * Copyright (c) 2004-2009 Oracle Corporation.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 * 
 *    Kohsuke Kawaguchi, Martin Eigenbrodt
 *
 *
 *******************************************************************************/ 

package org.jvnet.hudson.test;

import hudson.remoting.Which;
import hudson.FilePath;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URL;

/**
 * Ensures that <tt>hudson.war</tt> is exploded.
 *
 * <p> Depending on where the test is run (for example, inside Maven vs IDE),
 * this code attempts to use hudson.war from the right place, thereby improving
 * the productivity.
 *
 * @author Kohsuke Kawaguchi
 */
final class WarExploder {

    public static File getExplodedDir() throws Exception {
        // rethrow an exception every time someone tries to do this, so that when explode()
        // fails, you can see the cause no matter which test case you look at.
        // see http://www.nabble.com/Failing-tests-in-test-harness-module-on-hudson.ramfelt.se-td19258722.html
        if (FAILURE != null) {
            throw new Exception("Failed to initialize exploded war", FAILURE);
        }
        return EXPLODE_DIR;
    }
    private static File EXPLODE_DIR;
    private static Exception FAILURE;

    static {
        try {
            EXPLODE_DIR = explode();
        } catch (Exception e) {
            FAILURE = e;
        }
    }

    /**
     * Explodes hudson.war, if necesasry, and returns its root dir.
     */
    private static File explode() throws Exception {
        // are we in the hudson main workspace? If so, pick up hudson/main/war/resources
        // this saves the effort of packaging a war file and makes the debug cycle faster

        File d = new File(".").getAbsoluteFile();

        // just in case we were started from hudson instead of from hudson/main/...
        if (new File(d, "main/war/target/hudson").exists()) {
            return new File(d, "main/war/target/hudson");
        }

        for (; d != null; d = d.getParentFile()) {
            if (new File(d, ".hudson").exists()) {
                File dir = new File(d, "war/target/hudson");
                if (dir.exists()) {
                    System.out.println("Using hudson.war resources from " + dir);
                    return dir;
                }
            }
        }

        // locate hudson-war-for-test.jar
        File war = Which.jarFile(Class.forName("org.eclipse.hudson.war.Executable"));

        File explodeDir = new File("./target/hudson-for-test").getAbsoluteFile();
        File timestamp = new File(explodeDir, ".timestamp");

        if (!timestamp.exists() || (timestamp.lastModified() != war.lastModified())) {
            System.out.println("Exploding hudson.war at " + war);
            new FilePath(explodeDir).deleteRecursive();
            new FilePath(war).unzip(new FilePath(explodeDir));
            if (!explodeDir.exists()) // this is supposed to be impossible, but I'm investigating HUDSON-2605
            {
                throw new IOException("Failed to explode " + war);
            }
            new FileOutputStream(timestamp).close();
            timestamp.setLastModified(war.lastModified());
        } else {
            System.out.println("Picking up existing exploded hudson.war at " + explodeDir.getAbsolutePath());
        }

        return explodeDir;
    }
}