/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.maven.shared.utils.cli.shell;
  
  import java.io.File;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.List;
  
  import org.apache.maven.shared.utils.StringUtils;
  
  /**
   * Class that abstracts the Shell functionality,
   * with subclasses for shells that behave particularly, like
   *
   * <ul>
   * <li><code>command.com</code></li>
   * <li><code>cmd.exe</code></li>
   * </ul>
   *
   * @author <a href="mailto:carlos@apache.org">Carlos Sanchez</a>
   *
   */
  public class Shell implements Cloneable {
      private static final char[] DEFAULT_QUOTING_TRIGGER_CHARS = {' '};
  
      private String shellCommand;
  
      private final List<String> shellArgs = new ArrayList<String>();
  
      private boolean quotedArgumentsEnabled = true;
  
      private boolean unconditionalQuoting = false;
  
      private String executable;
  
      private String workingDir;
  
      private boolean quotedExecutableEnabled = true;
  
      private boolean singleQuotedArgumentEscaped = false;
  
      private boolean singleQuotedExecutableEscaped = false;
  
      private char argQuoteDelimiter = '\"';
  
      private char exeQuoteDelimiter = '\"';
  
      /**
       * Set the command to execute the shell (e.g. COMMAND.COM, /bin/bash,...).
       *
       * @param shellCommand the command
       */
      void setShellCommand(String shellCommand) {
          this.shellCommand = shellCommand;
      }
  
      /**
       * Get the command to execute the shell.
       *
       * @return the command
       */
      String getShellCommand() {
          return shellCommand;
      }
  
      /**
       * Set the shell arguments when calling a command line (not the executable arguments)
       * (e.g. /X /C for CMD.EXE).
       *
       * @param shellArgs the arguments to the shell
       */
      void setShellArgs(String[] shellArgs) {
          this.shellArgs.clear();
          this.shellArgs.addAll(Arrays.asList(shellArgs));
      }
  
      /**
       * Get the shell arguments
       *
       * @return the arguments
       */
      String[] getShellArgs() {
         if (shellArgs.isEmpty()) {
             return null;
         } else {
             return shellArgs.toArray(new String[0]);
         }
     }
 
     protected String quoteOneItem(String inputString, boolean isExecutable) {
         char[] escapeChars = getEscapeChars(isSingleQuotedExecutableEscaped(), isDoubleQuotedExecutableEscaped());
         return StringUtils.quoteAndEscape(
                 inputString,
                 isExecutable ? getExecutableQuoteDelimiter() : getArgumentQuoteDelimiter(),
                 escapeChars,
                 getQuotingTriggerChars(),
                 '\\',
                 unconditionalQuoting);
     }
 
     /**
      * Get the command line for the provided executable and arguments in this shell
      *
      * @param executableParameter executable that the shell has to call
      * @param argumentsParameter  arguments for the executable, not the shell
      * @return list with one String object with executable and arguments quoted as needed
      */
     List<String> getCommandLine(String executableParameter, String... argumentsParameter) {
         return getRawCommandLine(executableParameter, argumentsParameter);
     }
 
     /**
      * @param executableParameter Executable
      * @param argumentsParameter the arguments for the executable
      * @return the list on command line
      */
     List<String> getRawCommandLine(String executableParameter, String... argumentsParameter) {
         List<String> commandLine = new ArrayList<>();
         StringBuilder sb = new StringBuilder();
 
         if (executableParameter != null) {
             String preamble = getExecutionPreamble();
             if (preamble != null) {
                 sb.append(preamble);
             }
 
             if (isQuotedExecutableEnabled()) {
                 sb.append(quoteOneItem(executableParameter, true));
             } else {
                 sb.append(executableParameter);
             }
         }
         for (String argument : argumentsParameter) {
             if (sb.length() > 0) {
                 sb.append(' ');
             }
 
             if (isQuotedArgumentsEnabled()) {
                 sb.append(quoteOneItem(argument, false));
             } else {
                 sb.append(argument);
             }
         }
 
         commandLine.add(sb.toString());
 
         return commandLine;
     }
 
     char[] getQuotingTriggerChars() {
         return DEFAULT_QUOTING_TRIGGER_CHARS;
     }
 
     String getExecutionPreamble() {
         return null;
     }
 
     char[] getEscapeChars(boolean includeSingleQuote, boolean includeDoubleQuote) {
         StringBuilder buf = new StringBuilder(2);
         if (includeSingleQuote) {
             buf.append('\'');
         }
 
         if (includeDoubleQuote) {
             buf.append('\"');
         }
 
         char[] result = new char[buf.length()];
         buf.getChars(0, buf.length(), result, 0);
 
         return result;
     }
 
     /**
      * @return false in all cases
      */
     protected boolean isDoubleQuotedArgumentEscaped() {
         return false;
     }
 
     /**
      * @return {@link #singleQuotedArgumentEscaped}
      */
     protected boolean isSingleQuotedArgumentEscaped() {
         return singleQuotedArgumentEscaped;
     }
 
     boolean isDoubleQuotedExecutableEscaped() {
         return false;
     }
 
     boolean isSingleQuotedExecutableEscaped() {
         return singleQuotedExecutableEscaped;
     }
 
     /**
      * @param argQuoteDelimiterParameter {@link #argQuoteDelimiter}
      */
     void setArgumentQuoteDelimiter(char argQuoteDelimiterParameter) {
         this.argQuoteDelimiter = argQuoteDelimiterParameter;
     }
 
     char getArgumentQuoteDelimiter() {
         return argQuoteDelimiter;
     }
 
     /**
      * @param exeQuoteDelimiterParameter {@link #exeQuoteDelimiter}
      */
     void setExecutableQuoteDelimiter(char exeQuoteDelimiterParameter) {
         this.exeQuoteDelimiter = exeQuoteDelimiterParameter;
     }
 
     char getExecutableQuoteDelimiter() {
         return exeQuoteDelimiter;
     }
 
     /**
      * Get the full command line to execute, including shell command, shell arguments,
      * executable and executable arguments
      *
      * @param arguments arguments for the executable, not the shell
      * @return List of String objects, whose array version is suitable to be used as argument
      *         of Runtime.getRuntime().exec()
      */
     public List<String> getShellCommandLine(String... arguments) {
 
         List<String> commandLine = new ArrayList<>();
 
         if (getShellCommand() != null) {
             commandLine.add(getShellCommand());
         }
 
         if (getShellArgs() != null) {
             commandLine.addAll(getShellArgsList());
         }
 
         commandLine.addAll(getCommandLine(executable, arguments));
 
         return commandLine;
     }
 
     List<String> getShellArgsList() {
         return shellArgs;
     }
 
     /**
      * @param quotedArgumentsEnabled {@link #quotedArgumentsEnabled}
      */
     public void setQuotedArgumentsEnabled(boolean quotedArgumentsEnabled) {
         this.quotedArgumentsEnabled = quotedArgumentsEnabled;
     }
 
     boolean isQuotedArgumentsEnabled() {
         return quotedArgumentsEnabled;
     }
 
     void setQuotedExecutableEnabled(boolean quotedExecutableEnabled) {
         this.quotedExecutableEnabled = quotedExecutableEnabled;
     }
 
     boolean isQuotedExecutableEnabled() {
         return quotedExecutableEnabled;
     }
 
     /**
      * Sets the executable to run.
      * @param executable The executable.
      */
     public void setExecutable(String executable) {
         if ((executable == null) || (executable.length() == 0)) {
             return;
         }
         this.executable = executable.replace('/', File.separatorChar).replace('\\', File.separatorChar);
     }
 
     /**
      * @return The executable.
      */
     public String getExecutable() {
         return executable;
     }
 
     /**
      * Sets execution directory.
      * @param path The path which should be used as working directory.
      */
     public void setWorkingDirectory(String path) {
         if (path != null) {
             this.workingDir = path;
         }
     }
 
     /**
      * Sets execution directory.
      *
      * @param workingDirectory the working directory
      */
     public void setWorkingDirectory(File workingDirectory) {
         if (workingDirectory != null) {
             this.workingDir = workingDirectory.getAbsolutePath();
         }
     }
 
     /**
      * @return the working directory
      */
     public File getWorkingDirectory() {
         return workingDir == null ? null : new File(workingDir);
     }
 
     String getWorkingDirectoryAsString() {
         return workingDir;
     }
 
     /** {@inheritDoc} */
     public Object clone() {
         throw new RuntimeException("Do we ever clone this?");
         /*        Shell shell = new Shell();
         shell.setExecutable( getExecutable() );
         shell.setWorkingDirectory( getWorkingDirectory() );
         shell.setShellArgs( getShellArgs() );
         return shell;*/
     }
 
     void setSingleQuotedArgumentEscaped(boolean singleQuotedArgumentEscaped) {
         this.singleQuotedArgumentEscaped = singleQuotedArgumentEscaped;
     }
 
     void setSingleQuotedExecutableEscaped(boolean singleQuotedExecutableEscaped) {
         this.singleQuotedExecutableEscaped = singleQuotedExecutableEscaped;
     }
 
     public boolean isUnconditionalQuoting() {
         return unconditionalQuoting;
     }
 
     public void setUnconditionalQuoting(boolean unconditionalQuoting) {
         this.unconditionalQuoting = unconditionalQuoting;
     }
 }