#!/usr/bin/env perl
# -*-coding:utf-8 -*-
# Auto updated?
#   Yes
#File :
#   dayborn
#Author:
#   The-Repo-Club [wayne6324@gmail.com]
#Github:
#   https://github.com/The-Repo-Club/
#
# Created:
#   Thu 20 January 2022, 05:40:19 PM [GMT]
# Modified:
#   Fri 21 January 2022, 02:29:56 PM [GMT]
#
# Description:
#   This project was originally called Iteration. The aim was to generate a more
#   traditional version number from the delta of the two timestamps, the time the
#   project was born, and the time of the last change made.
#
#   In the end, it wound up being a nifty little program which simply outputs how
#   many days it has been since the project was born, hence the name.
#
# Dependencies:
#   perl (>= 5.22.1-9)
#

require Date::Format;
require Time::Piece;

use v5.22.1;
use strict;
use warnings;
use autodie;
use Date::Format 'time2str';
use Time::Piece;

no warnings 'uninitialized';

my $CurVer = '2021-02-01';
my $Progrm = 'dayborn';

sub Usage{
    print(qq{Usage: $Progrm [OPTS] [FILE]

            -h, --help               - Display this help information.
            -v, --version            - Output the version datestamp.
        } =~ tr/\t//dr)
}

while (defined($ARGV[0])){
    if ($ARGV[0] =~ '^(--help|-h|-\?)$'){
        Usage(1); exit(0)
    }elsif ($ARGV[0] =~ '^(--version|-v)$'){
        print("$CurVer\n"); exit(0)
    }elsif ($ARGV[0] =~ '^-'){
        die("Incorrect option(s) specified")
    }else{
        last
    }

    shift()
}

scalar(@ARGV) == 1 or die("File name required");
scalar(@ARGV) > 1 and die("Only one file at a time is valid");

-f $ARGV[0] or die("File '$ARGV[0]' not found");
-r $ARGV[0] or die("File '$ARGV[0]' unreadable");
-B $ARGV[0] and die("File '$ARGV[0]' is binary");

open(my $FH, '<', $ARGV[0]);

my ($Start, $Now);
while (<$FH>){
    /^# (Start|Modified) / or next;

    chomp(my @Arr = split(' '));

    # The following format (sans quotes) is expected:
    #
    #   '# Started On        - Mon 10 Feb 23:49:15 GMT 2020'
    #
    if ($Arr[1] eq 'Start') {
        $Start = Time::Piece->strptime(
            join(' ', @Arr[4,6,5,7,9]), '%a %b %d %T %Z %Y'
        )->epoch()
    }

    # The following format (sans quotes) is expected:
    #
    #   '# Modified On       - Tue 11 Feb 01:00:34 GMT 2020'
    #
    if ($Arr[1] eq 'Modified') {
        $Now = Time::Piece->strptime(
            join(' ', @Arr[4,6,5,7,9]), '%a %b %d %T %Z %Y'
        )->epoch()
    }
}

close($FH);

my $Project = ($ARGV[0] =~ m{(?:.*/)?([^/].*)})[0];
my $DeltaDay = ($Now - $Start) / 60 / 60 / 24;

printf("Project '%s' was born %.2f day's ago.\n", $Project, $DeltaDay)