#!/usr/bin/perl

#######################################
## test.pl
## Program to parse a txt file given in
## tab-delimited format of physio data
## Parses all files in a directory and
## compiles the results into one file
## Looks through desired folders in dir
#######################################

$dir_path = 'G:\\Test Data';
@dir_folds = ('Ts1', 'Ts10', 'Ts12', 'Ts13', 'Ts14', 'Ts15', 'Ts16', 'Ts17', 'Ts18', 'Ts19', 'Ts2',
              'Ts20', 'Ts21', 'Ts22', 'Ts23', 'Ts24', 'Ts25', 'Ts26', 'Ts27', 'Ts3', 'Ts4', 'Ts5',
              'Ts6', 'Ts7', 'Ts8', 'Ts9');  ## holds the folders at $dir_path where desired files are located
$full_path;  ## Full directory path
$avg_file = ">>averages.txt";  ## Name of file averages are written to (oppened for appending)
$full_name;  ## Full file name (i.e., with directory path)
$ln_num = 0;  ## Line number, used in @zeroat array
$i = 0;  ## Reference counter
$j = 0;  ## Reference counter (specifically for @avg_frmt array; counts through file loop)
$sum1 = 0;  ## HRT sum
$sum2 = 0;  ## SKT sum
$sum3 = 0;  ## EMG sum
$avg11 = 0;  ## HRT avg 1
$avg12 = 0;  ## HRT avg 2
$avg21 = 0;  ## SKT avg 1
$avg22 = 0;  ## SKT avg 2
$avg31 = 0;  ## EMG avg 1
$avg32 = 0;  ## EMG avg 2
@files;  ## Array to hold desired filenames
@avg_frmt;  ## Array to hold formatting for $avg_file document
@lines;  ## Array to hold lines of file
@lines1;  ## Holds first part to be aberaged
@lines2;  ## Holds second part to be averaged
@zeroat;  ## Tells where zeros are at in array @lines

## Do procedure for all desired folders at $dir_path
for $dir_fold(@dir_folds) {
  ## Print Status: i.e., which folder the program is currently on
  print "$dir_fold\n";

  ## Retrieve all .txt files at $dir_path\$dir_fold
  $full_path = "$dir_path\\$dir_fold";
  opendir(DIR, $full_path) or die "$full_path failed to open: $!";
  @files = grep { /\.txt$/ } readdir(DIR);
  closedir(DIR);

  ## Begin looping over files, compiling averages for each
  for $i_file(@files) {
    next if $i_file =~ /RAREEVENT/;
    $full_name = "$full_path\\$i_file";
    open(IN,$full_name) or die "$i_file failed to open: $!";
    @lines = <IN>;

    ## Print Status: i.e., which file the program is currently on
    print "\t$i_file\n";

    ## Retrieve desired rows
    for $curline(@lines) {
      $curline =~ /.*?\t.*?\t.*?\t.*?\t([05])/;  ## parse line
      $zeros[$ln_num] = $curline;
      $zeroat[$i] = $ln_num if $1 == 0;
      $ln_num++; $i++;
    }

    ## Take Average
    ## Get all points between the starting and ending points, and separate into different arrays
    for $i(@zeroat) {  ## $i is an index in @lines to where a zero is at
      $lines[$i] =~ /(.*?)\t.*?\t.*?\t.*?\t([05])/;  ## parse line
      if ($1 > .5 && $2 == 0) { 
        @lines1 = @lines[0..$i-1];  ## @lines1 equals the first $i-1 elements of @lines
        @lines2 = @lines[$i+1..$#lines];  ## @lines2 equals everything past the $i+1 element of @lines
        @lines = (@lines1,@lines2);  ## @lines equals @lines1 followed by @lines2 ({$i}th element removed)
      } ## the zero is in the middle: split for averaging
    }

    ## Reset sums
    $sum1 = 0;
    $sum2 = 0;
    $sum3 = 0;

    for $i(@lines1) {  ## go through first part and average
      $i =~ /.*?\t(.*?)\t(.*?)\t(.*?)\t5/;  ## parse line
      $sum1 += $1;
      $sum2 += $2;
      $sum3 += $3;
    }

    ## Get first average
    $avg11 = $sum1/$#lines1;
    $avg21 = $sum2/$#lines1;
    $avg31 = $sum3/$#lines1;

    ## Reset sums
    $sum1 = 0;
    $sum2 = 0;
    $sum3 = 0;

    for $i(@lines2) {  ## go through second part and average
      $i =~ /.*?\t(.*?)\t(.*?)\t(.*?)\t5/;  ## parse line
      $sum1 += $1;
      $sum2 += $2;
      $sum3 += $3;
    }

    ## Get second average
    $avg12 = $sum1/$#lines2;
    $avg22 = $sum2/$#lines2;
    $avg32 = $sum3/$#lines2;

    ## Put averages into tab delimited columns with desired format: File name followed by tab followed
    ## by averages; first line is resting condition; second line is cloud condition.
    $avg_frmt[$j] = "$i_file\t$avg11\t$avg21\t$avg31\n";  ## HRT, SKT, EMG is the
    $avg_frmt[$j+1] = "$i_file\t$avg12\t$avg22\t$avg32\n";  ## order for the averages
    $j += 2;
  }  ## End looping over files in folder
}  ## End looping over folders in directory

## Open and print averages to $avg_file
open(OUT,$avg_file) or die "$avg_file failed to be created: $!";
print OUT @avg_frmt;