/*******************************************************************************

 * Copyright (c) 2009 Symbian Foundation and/or its subsidiary(-ies).

 * All rights reserved.

 * This component and the accompanying materials are made available

 * under the terms of the License "Eclipse Public License v1.0"

 * which accompanies this distribution, and is available

 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

 *

 * Initial Contributors:

 * Symbian Foundation - initial contribution.

 * Contributors:

 * Description:

 * Overview:

 * Details:

 * Platforms/Drives/Compatibility:

 * Assumptions/Requirement/Pre-requisites:

 * Failures and causes:

 *******************************************************************************/

package org.symbian.tools.tmw.previewer.http;

import java.io.File;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.io.UnsupportedEncodingException;

import java.net.MalformedURLException;

import java.net.URI;

import java.net.URISyntaxException;

import java.net.URL;

import java.net.URLDecoder;

import java.net.URLEncoder;

import java.text.MessageFormat;

import java.util.Map;

import java.util.StringTokenizer;

import java.util.TreeMap;

import javax.servlet.ServletException;

import javax.servlet.ServletInputStream;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.eclipse.core.resources.IFile;

import org.eclipse.core.resources.IProject;

import org.eclipse.core.resources.ResourcesPlugin;

import org.eclipse.core.runtime.CoreException;

import org.eclipse.core.runtime.FileLocator;

import org.eclipse.core.runtime.IPath;

import org.eclipse.core.runtime.Path;

import org.json.simple.JSONObject;

import org.json.simple.parser.JSONParser;

import org.json.simple.parser.ParseException;

import org.symbian.tools.tmw.previewer.PreviewerException;

import org.symbian.tools.tmw.previewer.PreviewerPlugin;

import org.symbian.tools.tmw.previewer.core.IApplicationLayoutProvider;

import org.symbian.tools.tmw.previewer.http.handlers.DebuggerResourceProvider;

import org.symbian.tools.tmw.previewer.http.handlers.PreviewerStaticResourceProvider;

import org.symbian.tools.tmw.previewer.http.handlers.Providers;

public class WorkspaceResourcesServlet extends HttpServlet {

    private static final Map<String, String> EXTENSION_CONTENT_TYPE = new TreeMap<String, String>();

    private static final long serialVersionUID = -3217197074249607950L;

    static {

        EXTENSION_CONTENT_TYPE.put("htm", "text/html");

        EXTENSION_CONTENT_TYPE.put("html", "text/html");

        EXTENSION_CONTENT_TYPE.put("xml", "text/xml");

        EXTENSION_CONTENT_TYPE.put("plist", "application/octet-stream");

        EXTENSION_CONTENT_TYPE.put("gif", "image/gif");

        EXTENSION_CONTENT_TYPE.put("jpg", "image/jpeg");

        EXTENSION_CONTENT_TYPE.put("jpeg", "image/jpeg");

        EXTENSION_CONTENT_TYPE.put("png", "image/png");

        EXTENSION_CONTENT_TYPE.put("css", "text/css");

        EXTENSION_CONTENT_TYPE.put("js", "application/x-javascript");

        EXTENSION_CONTENT_TYPE.put("mp3", "audio/x-mpeg");

    }

    private static String encode(String path) {

        try {

            StringBuffer result = new StringBuffer();

            String[] segments = new Path(path).segments();

            for (int i = 0; i < segments.length; i++) {

                String string = segments[i];

                result.append("/");

                // java.net.URLEncoder encodes " " as "+" while Chrome needs "%20"

                StringTokenizer tokenizer = new StringTokenizer(string, " ", false);

                while (tokenizer.hasMoreElements()) {

                    result.append(URLEncoder.encode(tokenizer.nextToken(), "UTF-8"));

                    if (tokenizer.hasMoreTokens()) {

                        result.append("%20");

                    }

                }

            }

            return result.toString();

        } catch (UnsupportedEncodingException e) {

            // Something is horribly wrong - JRE doesn't have UTF8?

            throw new RuntimeException(e);

        }

    }

    public static IFile getFileFromUrl(String name) {

        final IPath path = getResourcePath(name);

        if (path != null) {

            final IProject project = ResourcesPlugin.getWorkspace().getRoot().getProject(path.segment(0));

            final IApplicationLayoutProvider provider = PreviewerPlugin.getExtensionsManager().getLayoutProvider(

                    project);

            if (provider != null) {

                try {

                    return provider.getWorkspaceFile(project, path.removeFirstSegments(1));

                } catch (CoreException e) {

                    PreviewerPlugin.log(e);

                }

            }

        }

        return null;

    }

    private static IPath getResourcePath(String name) {

        IPath p = null;

        try {

            String root = getHttpUrl(null);

            if (name != null && name.startsWith(root)) {

                final String fileName = URLDecoder.decode(name.substring(root.length()), "UTF-8");

                final IPath path = new Path(fileName);

                if (path.segmentCount() > 1) {

                    p = path;

                }

            }

        } catch (UnsupportedEncodingException e) {

            throw new RuntimeException(e);

        }

        return p;

    }

    public static String getHttpUrl(IFile file) {

        IPath p = new Path("/");

        if (file != null) {

            IApplicationLayoutProvider provider = PreviewerPlugin.getExtensionsManager().getLayoutProvider(

                    file.getProject());

            if (provider != null) {

            }

        }

        String uri = getServerURIForResource(p, null).toASCIIString();

        if (uri != null) {

            return uri;

        } else {

            return file.getLocationURI().toString();

        }

    }

    public static String getMimeTypeByExtension(String extension) {

        if (extension != null) {

            return EXTENSION_CONTENT_TYPE.get(extension.toLowerCase());

        } else {

            return null;

        }

    }

    public static File getPreviewerResource(String name) {

        try {

            IPath path = getResourcePath(name);

            if (path != null && path.segmentCount() > 1) {

                if (path.segmentCount() == 2 && HttpPreviewer.PREVIEW_STARTING_PAGE.equals(path.segment(1))) {

                    path = new Path(PreviewerStaticResourceProvider.PREVIEW_START);

                } else if (path.segmentCount() > 2

                        && PreviewerStaticResourceProvider.PREVIEW_PATH.equals(path.segment(1))) {

                    path = path.removeFirstSegments(1);

                } else {

                    return null;

                }

                URL pluginResource = FileLocator.find(PreviewerPlugin.getDefault().getBundle(), path, null);

                if (pluginResource != null) {

                    URL url = FileLocator.toFileURL(pluginResource);

                    if (url != null) {

                        return new File(url.getPath());

                    }

                }

            }

        } catch (IOException e) {

            PreviewerPlugin.log(e);

        }

        return null;

    }

    public static URI getPreviewerStartingPage(String widget) {

        return getServerURIForResource(new Path(widget).append(HttpPreviewer.PREVIEW_STARTING_PAGE).makeAbsolute(),

                null);

    }

    private static URI getServerURIForResource(IPath resourcePath, String debugSessionId) {

        try {

            String path = encode(WebappManager.WORKSPACE_RESOURCES_CONTEXT + resourcePath);

            path += debugSessionId == null ? "" : (String.format("?%s=%s",

                    DebuggerResourceProvider.DEBUG_SESSION_ID_PARAMETER, debugSessionId));

            URL url = new URL("http", WebappManager.getHost(), WebappManager.getPort(), path);

            return url.toURI();

        } catch (MalformedURLException e) {

            PreviewerPlugin.log(e);

        } catch (URISyntaxException e) {

            PreviewerPlugin.log(e);

        }

        return null;

    }

    private final Providers providers = new Providers();

    private void copyData(InputStream contents, OutputStream ouput) throws IOException {

        byte[] buf = new byte[4048];

        int i;

        while ((i = contents.read(buf)) >= 0) {

            ouput.write(buf, 0, i);

        }

    }

    @SuppressWarnings("unchecked")

    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        long time = 0;

        if (PreviewerPlugin.TRACE_SERVLET) {

            time = System.currentTimeMillis();

        }

        try {

            InputStream stream = providers.get(req.getPathInfo(), req.getParameterMap(), req.getSession().getId());

            String mimeType = getMimeTypeByExtension(new Path(req.getPathInfo()).getFileExtension());

            if (mimeType != null) {

                resp.setContentType(mimeType);

            }

            if (stream != null) {

                copyData(stream, resp.getOutputStream());

            } else {

                resp.setStatus(HttpServletResponse.SC_NOT_FOUND);

            }

        } catch (PreviewerException e) {

            PreviewerPlugin.log(e);

            throw new ServletException(e);

        }

        if (PreviewerPlugin.TRACE_SERVLET) {

            System.out.println(MessageFormat.format("Resource {0} was downloaded in {1}", req.getPathInfo(),

                    System.currentTimeMillis() - time));

        }

    }

    @SuppressWarnings("unchecked")

    @Override

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        ServletInputStream inputStream = req.getInputStream();

        byte[] buff = new byte[1024];

        StringBuilder builder = new StringBuilder();

        int l;

        while ((l = inputStream.read(buff)) > 0) {

            builder.append(new String(buff, 0, l, "UTF-8"));

        }

        inputStream.close();

        JSONObject object = null;

        try {

            Object parseResult = new JSONParser().parse(builder.toString());

            if (parseResult instanceof JSONObject) {

                object = (JSONObject) parseResult;

            }

        } catch (ParseException e) {

            PreviewerPlugin.log(e);

            throw new ServletException(e);

        }

        try {

            providers.post(req.getPathInfo(), req.getParameterMap(), object, req.getSession().getId());

        } catch (PreviewerException e) {

            throw new ServletException(e);

        }

        resp.setStatus(HttpServletResponse.SC_OK);

    }

    public static URI getDebugStartingPage(IProject project, String session) {

        return getServerURIForResource(project.getFullPath().append(HttpPreviewer.DEBUG_STARTING_PAGE).makeAbsolute(),

                session);

    }

}