<?php
/*
 *  $Id: SourceFileScanner.php 905 2010-10-05 16:28:03Z mrook $
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information please see
 * <http://phing.info>. 
 */

/**
 *  Utility class that collects the functionality of the various
 *  scanDir methods that have been scattered in several tasks before.
 *
 *  The only method returns an array of source files. The array is a
 *  subset of the files given as a parameter and holds only those that
 *  are newer than their corresponding target files.
 *  @package   phing.util
 */
class SourceFileScanner {

    /** Instance of FileUtils */
    private $fileUtils;
    
    /** Task this class is working for -- for logging purposes. */
    private $task;

    /**
     * @param task The task we should log messages through
     */
    function __construct($task) {
        $this->task = $task;
        $this->fileUtils = new FileUtils();
    }

    /**
     * Restrict the given set of files to those that are newer than
     * their corresponding target files.
     *
     * @param files   the original set of files
     * @param srcDir  all files are relative to this directory
     * @param destDir target files live here. if null file names
     *                returned by the mapper are assumed to be absolute.
     * @param FilenameMapper  knows how to construct a target file names from
     *                source file names.
     * @param force   Boolean that determines if the files should be
     *                forced to be copied.
     */
    function restrict(&$files, $srcDir, $destDir, $mapper, $force = false) {
        $now = time();
        $targetList = "";

        /*
          If we're on Windows, we have to munge the time up to 2 secs to
          be able to check file modification times.
          (Windows has a max resolution of two secs for modification times)
        */
        $osname = strtolower(Phing::getProperty('os.name'));

        // indexOf()
        $index = ((($res = strpos($osname, 'win')) === false) ? -1 : $res);
        if ($index  >= 0 ) {
            $now += 2000;
        }

        $v = array();

        for ($i=0, $size=count($files); $i < $size; $i++) {
        
            $targets = $mapper->main($files[$i]);
            if (empty($targets)) {
                $this->task->log($files[$i]." skipped - don't know how to handle it", Project::MSG_VERBOSE);
                continue;
            }

            $src = null;
            try {
                if ($srcDir === null) {
                    $src = new PhingFile($files[$i]);
                } else {
                    $src = $this->fileUtils->resolveFile($srcDir, $files[$i]);
                }
    
                if ($src->lastModified() > $now) {
                    $this->task->log("Warning: ".$files[$i]." modified in the future (".$src->lastModified()." > ".$now.")", Project::MSG_WARN);
                }
            } catch (IOException $ioe) {
                $this->task->log("Unable to read file ".$files[$i]." (skipping): " . $ioe->getMessage());
                continue;
            }
            
            $added = false;
            $targetList = "";

            for ($j=0,$_j=count($targets); (!$added && $j < $_j); $j++) {

                $dest = null;
                if ($destDir === null) {
                    $dest = new PhingFile($targets[$j]);
                } else {
                    $dest = $this->fileUtils->resolveFile($destDir, $targets[$j]);
                }

                if (!$dest->exists()) {
                    $this->task->log($files[$i]." added as " . $dest->__toString() . " doesn't exist.", Project::MSG_VERBOSE);
                    $v[] =$files[$i];
                    $added = true;
                } elseif ($src->lastModified() > $dest->lastModified()) {
                    $this->task->log($files[$i]." added as " . $dest->__toString() . " is outdated.", Project::MSG_VERBOSE );
                    $v[]=$files[$i];
                    $added = true;
                } elseif ($force === true) {
                    $this->task->log($files[$i]." added as " . $dest->__toString() . " is forced to be overwritten.", Project::MSG_VERBOSE );
                    $v[]=$files[$i];
                    $added = true;
                } else {
                    if (strlen($targetList) > 0) {
                        $targetList .= ", ";
                    }
                    $targetList .= $dest->getAbsolutePath();
                }
            }

            if (!$added) {
                $this->task->log($files[$i]." omitted as ".$targetList." ".(count($targets) === 1 ? " is " : " are ")."up to date.",  Project::MSG_VERBOSE);
            }

        }
        $result = array();
        $result = $v;
        return $result;
    }

    /**
     * Convenience layer on top of restrict that returns the source
     * files as PhingFile objects (containing absolute paths if srcDir is
     * absolute).
     */
    function restrictAsFiles(&$files, &$srcDir, &$destDir, &$mapper) {
        $res = $this->restrict($files, $srcDir, $destDir, $mapper);
        $result = array();
        for ($i=0; $i<count($res); $i++) {
            $result[$i] = new PhingFile($srcDir, $res[$i]);
        }
        return $result;
    }
}