<?php
echo "Spectrum Data Analyzer v5.0 : (c)2003-4 Max Vilimpoc.\n";
echo "    Thanks to Mark McHenry of the Shared Spectrum Company\n";
echo "    for furnishing the original equipment and measurement data.\n";
/* 
    Spectrum Data Analyzer v4.0 -- 09/07/2003 - 20:57:31 
    Benchmark -- Before v4.0 Modifications -- "Processing took 1941.41309595 seconds."
    v4.0 Modifications --
        two new structures:
        H: simplify data reading, arrays are one dimensional, 500 points each.
        V: two-dimensional array - 1: band, 2: GD image raster comments.
        create the V on the fly from each H.
        can we create each raster comment @ 500 points and then rescale using native code to 500 x n points?
    v5.0 Modifications --
        scaling down each section to some Hz/pixel ratio.
        simplifying the code, eliminating wasteful associative arrays.
        05/07/04 17:53:52
        05/08/04 01:12:18
        05/08/04 02:59:46   first successful test run of redesigned code.  5 data files ==  3.5774168968201 seconds.
                                                                          32            ==  21.388211011887 seconds.
                                                                         192            ==  134.71830010414 seconds.  O(n) time.
                                                                                            if only PHP/Win32 script-space had multi-threads.
                                                                       --all            ==  155.98033690453 seconds.
                                                                                            Super runtime improvement.
    v6.0 Modifications --
        05/09/04 09:56:24, 05/09/04 16:03:32
        overlaying maximum detected signals onto PSD area (since there's already a nice dBm legend on the left hand side.)
        added timeref to right hand side. datavis!
        --all       ==      211.99715900421 seconds.     for 192 datafiles @ 67K apiece.    rawdata-low/
        --all       ==      222.37490391731 seconds.     for 245 datafiles @ 49K apiece.    rawdata-high/
*/

function getmicrotime() {
    list($usec, $sec) = explode(" ",microtime()); 
    return ((float)$usec + (float)$sec); 
} 

$time_start = getmicrotime();
$time_last  = getmicrotime();

$version = 6;

$colors =  array(-120  => array("red" =>   0, "green" => 0, "blue" => 0),       // Apparently negative-indexed arrays are possible in PHP now.
                 -110  => array("red" =>  23, "green" => 0, "blue" => 0),       // (weren't available at first writing of this script.)
                 -100  => array("red" =>  46, "green" => 0, "blue" => 0),
                  -90  => array("red" =>  69, "green" => 0, "blue" => 0),
                  -80  => array("red" =>  92, "green" => 0, "blue" => 0),
                  -70  => array("red" => 115, "green" => 0, "blue" => 0),
                  -60  => array("red" => 138, "green" => 0, "blue" => 0),
                  -50  => array("red" => 161, "green" => 0, "blue" => 0),
                  -40  => array("red" => 184, "green" => 0, "blue" => 0),
                  -30  => array("red" => 207, "green" => 0, "blue" => 0),
                  -20  => array("red" => 230, "green" => 0, "blue" => 0),
                  -10  => array("red" => 255, "green" => 0, "blue" => 0)
                );

$range = min(array_keys($colors)) - max(array_keys($colors));

if (in_array('--low', $argv)) {
    $g_datadir      =  "rawdata-low/*.dat";
    $URL_margin     =  24;
    $file_prefix    =  'low';
    $k  =   array_search('--high', $argv);
    unset($argv[$k]);
}
if (in_array('--high', $argv)) {
    $g_datadir      =  "rawdata-high/*.dat";
    $URL_margin     =  5;
    $file_prefix    =  'high';
    $k  =   array_search('--low', $argv);
    unset($argv[$k]);
}

/*
//  As of PHP 4.3.5, I can just glob($g_datadir)
    $g_filestart    =  11287;
    $g_filestop     =  11478;
*/
$g_datadir_files  =  glob($g_datadir);
$g_numfiles       =  count($g_datadir_files);           //  this also serves as the im_height.
echo "Number of data files to process: $g_numfiles.\n";

$max_bwslice      =  0.0;
$min_bwslice      =  10000;

$y_scale          =  2;                                 //  y-direction stretch. used in --merge.

function ReadFileHeader() {
    global $fp, $nbands, $nsamples;
    $comment    =   fgets($fp);                         //  first line of every file == comment.
    $nsamples   =   fgets($fp);                         //  number of samples per band.
    $nbands     =   fgets($fp);                         //  this is the number of images to produce and should not change.
    $step       =   fgets($fp);                         //  not sure what this number controls.
}

function ReadDataHeader($band) {
    global $fp, $data;                                  //  $data's the global array holding the samples.
    $timestamp  =   fgets($fp);                         //  ignore this, assuming contiguity of sample datafile set.
    $data[$band]["fstart"]     =   (float) fgets($fp);
    $data[$band]["fstop"]      =   (float) fgets($fp);

    $dBadjust   =   fgets($fp);
    $dummy2     =   fgets($fp);
    $dummy3     =   fgets($fp);
    $dummy4     =   fgets($fp);
    $dummy5     =   fgets($fp);
}

function ReadBandData($band, $filename) {
    global $fp, $data, $nsamples, $maximum;
    for ($j = 0; $j <  $nsamples; $j++) {
    
        $in  =  (float) fgets($fp);
        if ($in > $maximum[$band][$j]) $maximum[$band][$j] = $in;
        
        $in  =  (int) ceil($in/10)*10;
        $data[$band][$filename][]  =  $in;
        
//      Look at this old and madly obfuscated dynamic array assignment! Simplification will lead to great speed improvements.
//      $data[$filename]["band"][$i]["data"][(string) (($bwslice * $j) + $data[$filename]["band"][$i]["fstart"])]   =   (float) fgets($fp);
    }
//  echo "$filename: band $band read.\n";
}

function DetermineScale() {
    global $data, $nbands, $nsamples, $bwslice, $max_bwslice, $scalefactor;
    
    for ($band = 0; $band < $nbands; $band++) {
        $bandwidth       =   $data[$band]["fstop"]  -  $data[$band]["fstart"];
        $bwslice[$band]  =   $bandwidth  /  ($nsamples - 1);
        $max_bwslice     =   max($max_bwslice, $bwslice[$band]);
    }
    
    for ($band = 0; $band < $nbands; $band++) {
        $scalefactor[$band] = round(($nsamples - 1) * ($bwslice[$band] / $max_bwslice));
    }
    
    echo "MHz/pixel resolution == $max_bwslice | kHz/pixel resolution == " . $max_bwslice * 1000 . "\n";
}

/****************************
    Main program loops
*****************************/
if (in_array('--all', $argv)) {
    unset($argv);
    $argv[] = '--chart';
    $argv[] = '--merge';
    $argv[] = '--markers';
    $argv[] = '--composite';
}

if (in_array('--chart', $argv)) {
    $fp = fopen($g_datadir_files[0], "r");
    ReadFileHeader();
    for ($i = 0; $i < $nbands; $i++) {
        $maximum[$i] = array_fill(0, $nsamples, -10000);                        // array of nsamples, all initially set to -10000. max() compare.
    }
    fclose($fp);

    foreach ($g_datadir_files as $g_filename) {
        $fp  = fopen($g_filename, "r");

        ReadFileHeader();
        for ($i = 0; $i < $nbands; $i++) {
            ReadDataHeader($i);
            ReadBandData($i, $g_filename);
        }
        print "$g_filename processed.\t";
        fclose($fp);
        print getmicrotime() - $time_last . " (seconds)\n";
        $time_last = getmicrotime();
    }

    for ($band = 0; $band < $nbands; $band++) {
    //  global $chart;                                      // this puppy holds the GD library graphics resources as an array of resource handles.
        $chart_width   =  $nsamples - 1;
        $chart_height  =  $g_numfiles;

        echo "-- creating chart -- " . $data[$band]["fstart"] . " -- " . $data[$band]["fstop"] . " MHz image == $chart_width x $chart_height unscaled. ";
        $chart[$band]  =  imagecreatetruecolor($chart_width, $chart_height) or die ("Cannot initialize new GD image stream!\n");
        foreach ($colors as $k => $v) {
            $chart_colors[$k] =  imagecolorallocate($chart[$band], $v["red"], $v["green"], $v["blue"]);
        }
        $yellow  =   imagecolorallocate($chart[$band], 255, 255, 64);
        
        print getmicrotime() - $time_last . " (seconds)\n";
        $time_last = getmicrotime();
    }

    for ($band = 0; $band < $nbands; $band++) {
        echo "-- plotting data -- ";
        $x_px    = 0;
        $y_px    = 0;

        foreach ($g_datadir_files as $g_filename) {
            array_pop($data[$band][$g_filename]);           // pop the last element off the array 501 x 1 --> 500 x 1.
    //      echo "$band:$g_filename: " . count($data[$band][$g_filename]) . "\n";

            foreach($data[$band][$g_filename] as $k) {
                imagesetpixel($chart[$band], $x_px++, $y_px, $chart_colors[$k]);
            }
            $x_px = 0; $y_px++;
        }
        
        $x_px = 0;
        array_pop($maximum[$band]);
        foreach($maximum[$band] as $dmax) {
            imagesetpixel($chart[$band], $x_px++, (int) ($g_numfiles * ($dmax / $range)), $yellow);
        }

        ($band < 10) ? $band_pad = "0" . $band : $band_pad = $band;
        imagepng($chart[$band], "sda$version.$file_prefix.band-$band_pad.png");
        print getmicrotime() - $time_last . " (seconds)\n";
        $time_last = getmicrotime();
    }
}

if (in_array('--merge', $argv)) {
    if (@!$data) {
        $fp  = fopen($g_datadir_files[0], "r");
        ReadFileHeader();
        for ($i = 0; $i < $nbands; $i++) {
            $maximum[$i] = array_fill(0, $nsamples, -10000);                        // array of nsamples, all initially set to -10000. max() compare.
            ReadDataHeader($i);
            ReadBandData($i, $g_datadir_files[0]);
        }
        fclose($fp);
    }
    
    DetermineScale();
    $combined   =   imagecreatetruecolor((int) array_sum($scalefactor), $g_numfiles*$y_scale);
    $combined_x =   0;
    
    for ($band = 0; $band < $nbands; $band++) {
        ($band < 10) ? $band_pad = "0" . $band : $band_pad = $band;
        $chart[$band]   =   imagecreatefrompng("sda$version.$file_prefix.band-$band_pad.png");
        list($chart_width, $chart_height) = getimagesize("sda$version.$file_prefix.band-$band_pad.png");
        
        $scaled[$band]  =   imagecreatetruecolor((int) $scalefactor[$band], $g_numfiles*$y_scale);
        if ($scaled[$band] && $chart[$band]) {
            imagecopyresized($scaled[$band], $chart[$band], 0, 0, 0, 0, (int) $scalefactor[$band], $g_numfiles*$y_scale, $chart_width, $chart_height);
            imagepng($scaled[$band], "sda$version.$file_prefix.scaled-$band_pad.png");
            imagecopy($combined, $scaled[$band], $combined_x, 0, 0, 0, (int) $scalefactor[$band], $g_numfiles*$y_scale);
            $combined_x += (int) $scalefactor[$band];
        }
        print "-- scaling and merging -- ";
        print getmicrotime() - $time_last . " (seconds)\n";
        $time_last = getmicrotime();
    }

    print "-- saving combined spectrum image -- ";
    imagepng($combined, "sda$version.$file_prefix.combined.png");
    print getmicrotime() - $time_last . " (seconds)\n";
    $time_last = getmicrotime();
}

if (in_array('--markers', $argv)) {
    print "-- adding dBm scale and freq markers --\n";
    $dbm_ref_width  = 50;
    $dbm_ref_height = $g_numfiles * $y_scale;
    $dbm_ref_colors = count($colors);
    $dbm_ref = imagecreatetruecolor($dbm_ref_width, $dbm_ref_height);
    $dbm_ref_scaley = (int) ($dbm_ref_height  / $dbm_ref_colors);
    $dbm_ref_marginr = 4;
    $dbm_ref_y = 0;

    $white = imagecolorallocate($dbm_ref, 255, 255, 255);

    foreach (array_reverse($colors, true) as $k => $v) {
        $chart_colors[$k] =  imagecolorallocate($dbm_ref, $v["red"], $v["green"], $v["blue"]);
        imagefilledrectangle($dbm_ref, 0, $dbm_ref_y, $dbm_ref_width, $dbm_ref_y + $dbm_ref_scaley, $chart_colors[$k]);
        $dbm_ref_bbox = imagettfbbox(12, 0, 'Vera.ttf', $k);
        imagettftext ($dbm_ref, 12, 0, $dbm_ref_width - $dbm_ref_marginr  - ($dbm_ref_bbox[2] - $dbm_ref_bbox[0]), $dbm_ref_y + $dbm_ref_scaley - 5, $white, 'Vera.ttf', $k);
        $dbm_ref_y += $dbm_ref_scaley;
    }

    imagepng($dbm_ref, "sda$version.$file_prefix.dbmref.png");

    if (@!data) {
        $fp  = fopen($g_datadir_files[0], "r");
        ReadFileHeader();
        for ($i = 0; $i < $nbands; $i++) {
            $maximum[$i] = array_fill(0, $nsamples, -10000);                        // array of nsamples, all initially set to -10000. max() compare.
            ReadDataHeader($i);
            ReadBandData($i, $g_datadir_files[0]);
        }
        fclose($fp);
        DetermineScale();
    }

    list($combined_width, $combined_height) = getimagesize("sda$version.$file_prefix.combined.png") or die("ERROR: sda$version.$file_prefix.combined.png is missing. Run 'php sda$version.php --merge'.\n");
    $div_line = 1;
    $freq_ref_height = 40;
    $freq_ref_width  = $combined_width + $dbm_ref_width + $div_line;
    $freq_ref = imagecreatetruecolor($freq_ref_width, $freq_ref_height);
    $freq_ref_x = 0;
    $freq_ref_margin = 3;

    $white_line = imagecolorallocatealpha($freq_ref, 255, 255, 255, 64);
    $white      = imagecolorallocate($freq_ref, 255, 255, 255);

    for ($band = 0; $band < $nbands; $band++) {
        $freq_ref_bbox = imagettfbbox(12, 0, 'Vera.ttf', $data[$band]["fstart"]);
        imagettftext($freq_ref, 12, 0, $freq_ref_x + $freq_ref_margin, $freq_ref_height - 5, $white, 'Vera.ttf', $data[$band]["fstart"]);
        imageline($freq_ref, $freq_ref_x, 0, $freq_ref_x, $freq_ref_height, $white_line);
        $freq_ref_x += $scalefactor[$band];
    }
    imageline($freq_ref, 0, 0, $freq_ref_width, 0, $white_line);

    imagepng($freq_ref, "sda$version.$file_prefix.freqref.png");

    $dbm_legend_bbox = imagettfbbox(12, 0, 'Vera.ttf', 'dBm');
    $freq_legend_bbox = imagettfbbox(12, 0, 'Vera.ttf', 'MHz');
    $legend_ref  =  imagecreatetruecolor($dbm_ref_width, $freq_ref_height);
    $white       =  imagecolorallocate($legend_ref, 255, 255, 255);
    imagettftext($legend_ref, 10, 0, 2, 14, $white, 'Vera.ttf', 'dBm');
    imagettftext($legend_ref, 10, 0, $dbm_ref_width - 29, $freq_ref_height - 5, $white, 'Vera.ttf', 'MHz');
    imagesetthickness($legend_ref, 2);
    imageline($legend_ref, $dbm_ref_width, 0, 0, $freq_ref_height, $white);
    imagepng($legend_ref, "sda$version.$file_prefix.legendref.png");
}

if (in_array('--composite', $argv)) {
    if (@!$data) {
        $fp  = fopen($g_datadir_files[0], "r");
        ReadFileHeader();
        for ($i = 0; $i < $nbands; $i++) {
            $maximum[$i] = array_fill(0, $nsamples, -10000);                        // array of nsamples, all initially set to -10000. max() compare.
            ReadDataHeader($i);
            ReadBandData($i, $g_datadir_files[0]);
        }
        fclose($fp);
    }
    DetermineScale();
    $combined_ref_x = 0;
    list( $dbm_ref_width,  $dbm_ref_height) = getimagesize("sda$version.$file_prefix.dbmref.png") or die("ERROR: sda$version.$file_prefix.dbmref.png is missing. Run 'php sda$version.php --markers'.\n");
    list($combined_width, $combined_height) = getimagesize("sda$version.$file_prefix.combined.png") or die("ERROR: sda$version.$file_prefix.combined.png is missing. Run 'php sda$version.php --merge'.\n");
    list($freq_ref_width, $freq_ref_height) = getimagesize("sda$version.$file_prefix.freqref.png") or die("ERROR: sda$version.$file_prefix.freqref.png is missing. Run 'php sda$version.php --markers'.\n");
    list($legend_ref_width, $legend_ref_height) = getimagesize("sda$version.$file_prefix.legendref.png") or die ("ERROR: sda$version.$file_prefix.legendref.png is missing. Run 'php sda$version.php --markers.\n");

    if (@!$dbm_ref)  $dbm_ref   =  imagecreatefrompng("sda$version.$file_prefix.dbmref.png");
    if (@!$combined) $combined  =  imagecreatefrompng("sda$version.$file_prefix.combined.png");
    if (@!$freq_ref) $freq_ref  =  imagecreatefrompng("sda$version.$file_prefix.freqref.png");
    if (@!$legend_ref) $legend_ref  =  imagecreatefrompng("sda$version.$file_prefix.legendref.png");

    $white     =   imagecolorallocatealpha($combined, 255, 255, 255, 64);     // use alpha overlay on spectrum measurement data.
    for ($band = 0; $band < $nbands; $band++) {
        imageline($combined, $combined_ref_x, 0, $combined_ref_x, $combined_height, $white);
        $combined_ref_x += $scalefactor[$band];
    }
    
    $time_ref_width = 105;
    $time_ref_height = $dbm_ref_height + $combined_height;
    $time_scale_height = $combined_height;
    $time_ref  = imagecreatetruecolor($time_ref_width, $time_ref_height);
    $white = imagecolorallocate($time_ref, 255, 255, 255);
    $white_line = imagecolorallocatealpha($time_ref, 255, 255, 255, 64);     // use alpha overlay on spectrum measurement data.
    imageline($time_ref, 0, 0, 0, $time_scale_height, $white_line);
    $skip = (count($g_datadir_files) - 1) / 3;
    for ($a = 0; $a < 4; $a++)
    {
        $fp = fopen($g_datadir_files[(int) ($a * $skip)], "r");
        ReadFileHeader();
        $timestamp  =   fgets($fp);
        $timestamp  =   substr($timestamp, 28, 11);
        print "adding timestamp ref -- " . $timestamp . " --\n";
        
        if ($a == 0) imagettftext($time_ref, 12, 0, 5, $time_scale_height * ($a / 3) + 15, $white, 'Vera.ttf', $timestamp);
        if ($a == 3) imagettftext($time_ref, 12, 0, 5, $time_scale_height * ($a / 3) - 5,  $white, 'Vera.ttf', $timestamp);
        if ($a > 0 && $a < 3) imagettftext($time_ref, 12, 0, 5, ($time_scale_height - 30) * ($a / 3) + 15, $white, 'Vera.ttf', $timestamp);
        fclose($fp);
    }
    imagepng($time_ref, "sda$version.$file_prefix.timeref.png");

    $composite_width  = $dbm_ref_width + $combined_width + $time_ref_width;
    $composite_height = $freq_ref_height + $combined_height;
    $composite = imagecreatetruecolor($composite_width, $composite_height);
    imagecopy($composite, $dbm_ref, 0, 0, 0, 0, $dbm_ref_width, $dbm_ref_height);
    imagecopy($composite, $combined, $dbm_ref_width, 0, 0, 0, $combined_width, $combined_height);
    imagecopy($composite, $legend_ref, 0, $dbm_ref_height, 0, 0, $legend_ref_width, $legend_ref_height);
    imagecopy($composite, $freq_ref, $dbm_ref_width, $combined_height, 0, 0, $freq_ref_width, $freq_ref_height);
    imagecopy($composite, $time_ref, $dbm_ref_width + $combined_width, 0, 0, 0, $time_ref_width, $time_ref_height);
    
    /* finishing touches -- URL */
    $url_color = imagecolorallocate($composite, 255, 190, 33);
    imagettftext($composite, 12, 0, $composite_width - 265, $composite_height - $URL_margin, $url_color, 'Vera.ttf', 'http://vilimpoc.org/research/sda/');

    imagepng($composite, "sda$version.$file_prefix.composite.png");
}

print "Processing took " . (getmicrotime() - $time_start) . " seconds.\n";
?>