#!/bin/perl
use strict;
use warnings;
use feature("signatures");

use File::Copy;
use File::Path("make_path");
use List::Util("max");

sub fs_root($file_name) {
    chomp(my $ret = `stat -c %m $file_name`);
    return $ret;
}

sub file_info($file) {
    my $file_name = `basename $file`;
    my $file_path = `realpath -s $file`;
    my $file_fs_root = fs_root($file_name);

    chomp($file_name, $file_path, $file_fs_root);
    return ($file_name, $file_path, $file_fs_root);
}

sub trash_dirs($file_fs_root) {
    my $data_path = "$ENV{'XDG_DATA_HOME'}" // "$ENV{'HOME'}/.local/share";

    my $trash_dir;
    if ($file_fs_root eq fs_root($data_path)) {
        $trash_dir = "$data_path/Trash/";
    } else {
        $trash_dir = "$file_fs_root/.Trash/"
    }

    return "${trash_dir}info", "${trash_dir}files";
}

sub target_file_name($file_name, $trash_file_path) {
    opendir(my $dir, "$trash_file_path") or die "$!\n";
    my $existing_suffix_nums = map(($_ =~ /^${file_name}\.~(\d)~/), readdir $dir);
    my $suffix_num = max($existing_suffix_nums) + 1;
    my $suffix = "~" . $suffix_num . "~";
    closedir($dir);

    return "${file_name}.${suffix}";
}

sub write_file($file_path, $contents) {
    open(FH, '>', $file_path) or die "$!\n";
    print FH $contents;
}

# NOTE: Execution starts here

if ($#ARGV + 1 != 1) {
    die "Bad Arguments\n";
}

stat $ARGV[0] or die "$!\n";
my ($file_name, $file_src, $file_fs_root) = file_info($ARGV[0]);
my ($trash_info_path, $trash_file_path) = trash_dirs($file_fs_root);
my $target_name = target_file_name($file_name, $trash_file_path);
chomp(my $deletion_time = `date -u +%Y%m%dUTC%T`);

my $info_contents = <<EOF;
[Trash Info]
Path=$file_src
DeletionDate=$deletion_time
EOF

make_path($trash_info_path, $trash_file_path);
move($file_src, "$trash_file_path/$target_name") or die "$!\n";
write_file("$trash_info_path/$target_name", $info_contents) or die "$!\n";