/*
 *  Copyright 1999-2004 The Apache Software Foundation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package org.apache.jasper;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

import org.apache.jasper.compiler.CommandLineCompiler;
import org.apache.jasper.compiler.Compiler;
import org.apache.jasper.compiler.JspReader;
import org.apache.jasper.compiler.ServletWriter;
import org.apache.jasper.servlet.JasperLoader;

/**
 * Holds data used on a per-page compilation context that would otherwise spill
 * over to other pages being compiled.  Things like the taglib classloaders
 * and directives.
 *
 *@author Danno Ferrin
 */
public class CommandLineContext implements JspCompilationContext {

    String classPath;
    JspReader reader;
    ServletWriter writer;
    JasperLoader loader;
    boolean errPage;
    String jspFile;
    String servletClassName;
    String servletPackageName;
    String servletJavaFileName;
    String contentType;
    Options options;

    String uriBase;
    File uriRoot;

    boolean packageNameLocked;
    boolean classNameLocked;
    boolean outputInDirs;

    public CommandLineContext(JasperLoader newLoader, String newClassPath,
                              String newJspFile, String newUriBase,
                              String newUriRoot, boolean newErrPage,
                              Options newOptions)
    throws JasperException
    {
        loader = newLoader;
        classPath = newClassPath;
        uriBase = newUriBase;
        String tUriRoot = newUriRoot;
        jspFile = newJspFile;
        errPage = newErrPage;
        options = newOptions;

        if (uriBase == null) {
            uriBase = "/";
        } else if (uriBase.charAt(0) != '/') {
            // strip the basde slash since it will be combined with the
            // uriBase to generate a file
            uriBase = "/" + uriBase;
        }

        if (uriBase.charAt(uriBase.length() - 1) != '/') {
            uriBase += '/';
        }

        if (tUriRoot == null) {
            uriRoot = new File("");
        } else {
            uriRoot = new File(tUriRoot);
            if (!uriRoot.exists() || !uriRoot.isDirectory()) {
               throw new JasperException(
                        Constants.getString("jsp.error.jspc.uriroot_not_dir"));
            }
        }
    }

    /**
     * The classpath that is passed off to the Java compiler. 
     */
    public String getClassPath() {
        return classPath;
    }
    
    /**
     * Get the input reader for the JSP text. 
     */
    public JspReader getReader() {
        return reader;
    }
    
    /**
     * Where is the servlet being generated?
     */
    public ServletWriter getWriter() {
        return writer;
    }
    
    /**
     * What class loader to use for loading classes while compiling
     * this JSP? I don't think this is used right now -- akv. 
     */
    public ClassLoader getClassLoader() {
        return loader;
    }

    public void addJar( String jar ) throws IOException  {
	loader.addJar( jar );
    }
    
    /**
     * Are we processing something that has been declared as an
     * errorpage? 
     */
    public boolean isErrorPage() {
        return errPage;
    }
    
    /**
     * What is the scratch directory we are generating code into?
     * FIXME: In some places this is called scratchDir and in some
     * other places it is called outputDir.
     */
    public String getOutputDir() {
        return options.getScratchDir().toString();
    }
    
    /**
     * Path of the JSP URI. Note that this is not a file name. This is
     * the context rooted URI of the JSP file. 
     */
    public String getJspFile() {
        return jspFile;
    }
    
    /**
     * Just the class name (does not include package name) of the
     * generated class. 
     */
    public String getServletClassName() {
        return servletClassName;
    }
    
    /**
     * The package name into which the servlet class is generated. 
     */
    public String getServletPackageName() {
        return servletPackageName;
    }

    /**
     * Utility method to get the full class name from the package and
     * class name. 
     */
    public String getFullClassName() {
        String pkg = getServletPackageName();
        if (pkg != null) {
            pkg += ".";
        } else {
            pkg = "";
        }
        return pkg + getServletClassName();
   }

    /**
     * Full path name of the Java file into which the servlet is being
     * generated. 
     */
    public String getServletJavaFileName() {
        if (outputInDirs) {
            return getServletPackageName().replace('.', File.separatorChar)
                   + servletJavaFileName;
        } else {
            return servletJavaFileName;
        }
    }

    /**
     * Are we keeping generated code around?
     */
    public boolean keepGenerated() {
        return options.getKeepGenerated();
    }

    /**
     * What's the content type of this JSP? Content type includes
     * content type and encoding. 
     */
    public String getContentType() {
        return contentType;
    }

    /**
     * Get hold of the Options object for this context. 
     */
    public Options getOptions() {
        return options;
    }

    public void setContentType(String contentType) {
        this.contentType = contentType;
    }

    public void setReader(JspReader reader) {
        this.reader = reader;
    }
    
    public void setWriter(ServletWriter writer) {
        this.writer = writer;
    }
    
    public void setServletClassName(String servletClassName) {
        if (classNameLocked) {
            //System.out.println("Did not change clazz to " + servletClassName);
        } else {
            this.servletClassName = servletClassName;
        }
    }
    
    public void setServletPackageName(String servletPackageName) {
        if (packageNameLocked) {
            //System.out.println("Did not change pkg to " + servletPackageName);
        } else {
            this.servletPackageName = servletPackageName;
        }
    }
    
    public void setServletJavaFileName(String servletJavaFileName) {
        this.servletJavaFileName = servletJavaFileName;
    }
    
    public void setErrorPage(boolean isErrPage) {
        errPage = isErrPage;
    }

    public void lockPackageName() {
        packageNameLocked = true;
    }

    public void lockClassName() {
        classNameLocked = true;
    }

    public void setOutputInDirs(boolean newValue) {
        outputInDirs = true;
    }

    public boolean isOutputInDirs() {
        return outputInDirs;
    }

    /**
     * Create a "Compiler" object based on some init param data. This
     * is not done yet. Right now we're just hardcoding the actual
     * compilers that are created. 
     */
    public Compiler createCompiler() throws JasperException {
        return new CommandLineCompiler(this);
    }


    /** 
     * Get the full value of a URI relative to this compilations context
     * uses current file as the base.
     */
    public String resolveRelativeUri(String uri) {
        if (uri.startsWith("/")) {
            return uri;
        } else {
            return uriBase + uri;
        }
    }


    /**
     * Gets a resource as a stream, relative to the meanings of this
     * context's implementation.
     *@returns a null if the resource cannot be found or represented 
     *         as an InputStream.
     */
    public java.io.InputStream getResourceAsStream(String res) {
        InputStream in;
        // fisrt try and get it from the URI
        try {
            in = new FileInputStream(getRealPath(res));
        } catch (IOException ioe) {
            in = null;
        }
        // next, try it as an absolute name
        if (in == null) try {
            in = new FileInputStream(res);
        } catch (IOException ioe) {
            in = null;
        }
        // that dind't work, last chance is to try the classloaders
        if (in == null) {
            in = loader.getResourceAsStream(res);
        }
        return in;
    }


    /** 
     * Gets the actual path of a URI relative to the context of
     * the compilation.
     */
    public String getRealPath(String path) {
        path = resolveRelativeUri(path);
        if (path.startsWith("/")) {
            path = path.substring(1);
        }
        // if path is relative, 
        // prepends the eventualy webapp relative path
        // of the currently processed jsp
        // -> included jsp uri's have not to be webapp relative
        if ( ( ! path.startsWith( File.separator ) ) && ( ! jspFile.endsWith( path ) ) ) {
        	int i = jspFile.lastIndexOf( File.separatorChar );
        	if ( i >= 0 ) 
        		path = jspFile.substring( 0, i + 1 ) + path;
        		
        }
        File f = new File(uriRoot, path.replace('/', File.separatorChar));
        return f.getAbsolutePath();
    }

}