#!/usr/bin/perl
#
# 更新履歴のグラフを出力
# 月初めに実行させる
#

### 設定 ###
# gnuplot のパス
$gnuplot = '/home/yosh/bin/gnuplot';

# 出力先画像
$pngfile = '/home/yosh/www/accesslog.png';

# ログデータ
$logfile = '/home/yosh/www/accesslog.txt';

# アクセスログのあるディレクトリ
$accpath = '/home/yosh/www/cgi-bin/acc/logs/';

# gnuplot 設定ファイル
$pltfile = 'accesslog.plt';


### メイン ###

# 先月の年月を取得
($month, $year) = (localtime(time))[4,5];
$year += 1900;
if ($month == 0) {
    $month = 12;
    $year--;
}

&makeLogFile($year, $month);
&makePltFile($year, $month);
system("$gnuplot $pltfile");

unlink($pltfile);

exit;

### ログファイルを生成 ###
sub makeLogFile {
  my ($year, $month) = @_;
  my $cnt=0;
  my $source = sprintf("%saccess_log.%4d%02d00.cgi", $accpath, $year, $month);

  open(ACC, "$source") || die;
  while (<ACC>) { $cnt++; }
  close(ACC);
  open(LOG, ">>$logfile");
  print LOG "$year/$month\t$cnt\r\n"; # 一応CR+LF
  close(LOG);
}

### pltファイルを作成 ###
sub makePltFile {
  my ($year, $month) = @_;
  my $linenum = ($year-2004)*12 + $month - 5;
  my $line, $year=0;
  my $temp, $label = "\"'04/5\" 0";

  $line = $linenum + 5;
  while ($line>12) {
    $year++;
    $temp = sprintf("\"'%02d/1\" %d", $year+4, $year*12 -4);
    $label .= ", $temp";
    $line -= 12;
  }
  if ($line!=1) {
    $temp = sprintf("\"'%02d/%d\" %d", $year+4, $line, $linenum);
    $label .= ", $temp";
  }

  open(PLT, ">$pltfile") || die;
  print PLT <<EOM;
set terminal png transparent xffffff
set size 0.8, 0.6
set output "$pngfile"
set xlabel "Year/Month"
set ylabel "PV"
set yrange [0:25000]
set xrange [0:$linenum]
set xtics ($label)
plot "$logfile" using 0:2 title "" with linespoints
EOM
  close(PLT);
}