#!/usr/bin/perl

use strict;
use warnings;
use Time::Piece;

use HTTP::Tiny;
use JSON::MaybeXS;

# For wrapping comment blocks.
use Unicode::LineBreak;
my $lb = Unicode::LineBreak->new(ColMax => 76); # Default is 76.

# Printing UTF-8 to STDOUT.
binmode(STDOUT, "encoding(UTF-8)");

die "usage: draco [-dhv] <url>\n" unless scalar @ARGV;

my $DEBUG;
my $VERSION = "v0.2.2";
# Dispatch table to be parsed before url.
my %dispatch = (
    '-v'  => sub { print "Draco $VERSION\n"; exit; },
    '-d'  => sub { $DEBUG = 1; print STDERR "draco: debug on.\n"; },
    '-h'  => sub { print qq{Draco $VERSION

Options:
    -d
        Turn on debug messages. Debug messages will be printed to
        STDERR.
    -h
        Print this help.
    -v
        Print version.

Environment Variables:
    FETCH_ALL
        Fetch all comments. This will make multiple HTTP calls to
        reddit. This doesn't fetch *all* the comments.
};
                   exit;
               },
);
if (exists $dispatch{$ARGV[0]}) {
    # shift @ARGV to get $url in next shift.
    $dispatch{shift @ARGV}->();
}

# This is the start time.
my $start_time = time;
my $last_log = $start_time;

# $url contains the reddit post. Raise the limit to 500 comments which
# is the maximum reddit allows.
my $url = shift @ARGV;
my $json_url = "${url}.json?limit=500&sort=top";

my $http = HTTP::Tiny->new( verify_SSL => 1 );

# Fetch the post.
print_time() if $DEBUG;
print STDERR "fetching `$json_url'.\n" if $DEBUG;
my $response = get_response($json_url);

# Decode json.
print STDERR "decoding json response.\n" if $DEBUG;
my $json_data = decode_json($response->{content});

# $post contains post data
my $post = $json_data->[0]->{data}->{children}->[0]->{data};

# $comments contains comment data. We are interested in: replies,
# author, body, created_utc & permalink.
my $comments = $json_data->[1]->{data}->{children};

# Start the Org document.
print "#+", "STARTUP:content\n";

# Print the date.
my $current_date = Time::Piece->new->strftime('%+');
print "#+", "DATE: $current_date\n";
print "\n";

# Print the post title & it's link.
print "* ", "[[$post->{url}][$post->{title}]]\n";

# Add various details to :PROPERTIES:.
print ":PROPERTIES:\n";
# Include the created date & archive date in properties.
print ":CREATED_UTC: ",
    Time::Piece->strptime($post->{created_utc}, '%s')
    ->strftime('%+'), "\n";

print ":ARCHIVE_DATE: $current_date\n";
foreach my $detail (qw( subreddit created_utc author permalink
                        upvote_ratio ups downs score )) {
    print ":${detail}: =$post->{$detail}=\n"
        if scalar $post->{$detail};
}
print ":END:\n";

# Add selftext if present.
print "\n#+BEGIN_SRC markdown\n",
    # Break the text at 76 column & add 2 space before every new line.
    "  ", $lb->break($post->{selftext}) =~ s/\n/\n\ \ /gr, "\n",
    "#+END_SRC\n"
    if scalar $post->{selftext};

my (@http_calls, %counter);
$counter{print_comment_chain_call} = 0;
$counter{iterate_over_comments_call} = 0;

print_time() if $DEBUG;
print STDERR "iterating over top-level comments.\n" if $DEBUG;

# We are going to put a dot after each HTTP call.
print STDERR "each dot is a HTTP call.\n" if $DEBUG;

# Iterate over top-level comments. The second argument is level
# (depth), it should be 0 for top-level comments.
iterate_over_comments($comments, 0);

# Seperate the dots from the rest by a line break.
print STDERR "\n" if $DEBUG;
print_time() if $DEBUG;

# Print important stats.
print STDERR "\n" if $DEBUG;
print STDERR "total http calls: ",
    scalar @http_calls, "\n" if $DEBUG;
print STDERR "total print_comment_chain calls: ",
    $counter{print_comment_chain_call}, "\n" if $DEBUG;
print STDERR "total iterate_over_comments calls: ",
    $counter{iterate_over_comments_call}, "\n" if $DEBUG;

sub print_time {
    print STDERR "    ";
    print STDERR "time since [start, last log]: [", time - $start_time,
        ", ", time - $last_log, "] seconds\n";
    $last_log = time;
}

sub get_response {
    my $url = shift @_;
    print STDERR "." if $DEBUG;
    my $response = $http->get($url);
    push @http_calls, $url;
    die "Unexpected response - $response->{status}: $response->{reason} : $url"
        unless $response->{success};
    return $response;
}

# Pass <comment id> as argument and it'll return you the json url to
# that comment thread.
sub get_comment_thread_from_id {
    my $comment_id = shift @_;

    # Reddit doesn't like this kind of url:
    #     http://<reddit>/<post_id>//<comment_id>.json
    #
    # It wants this kind of url:
    #     http://<reddit>/<post_id>/<comment_id>.json
    #
    # Notice the extra '/' in first url.
    my $json_url = $url;
    $json_url .= "/" unless substr $url, -1 eq "/";
    $json_url .= "${comment_id}.json?limit=500&sort=top";
    return $json_url;
}

# This was being used multiple times so I moved it to a subroutine.
# It'll take $comment_id & return $comments.
sub get_all_comments_from_id {
    my $comment_id = shift @_;
    my $json_url = get_comment_thread_from_id($comment_id);

    # Fetch the comment.
    my $response = get_response($json_url);

    # Decode json.
    my $json_data = decode_json($response->{content});

    # $comments contains comment data.
    my $comments = $json_data->[1]->{data}->{children};

    return $comments;
}

# First argument requires $comments & second is the level (depth).
sub iterate_over_comments {
    my $comments = shift @_;
    my $level = shift @_;

    $counter{iterate_over_comments_call}++;

    foreach my $co<style>pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .ges { font-weight: bold; font-style: italic } /* Generic.EmphStrong */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */</style><div class="highlight"><pre><span></span>                               ━━━━━━━━━
                                 OCTANS

                                Andinus
                               ━━━━━━━━━


Table of Contents
─────────────────

1. Demo
2. Documentation
.. 1. Implementation
.. 2. Options


Octans is a program to solve Algot&#39;s Wordplay (Wordsearch) puzzles.

• Website: &lt;https://andinus.nand.sh/octans&gt;
• Source: &lt;https://git.tilde.institute/andinus/octans&gt;
• GitHub: &lt;https://github.com/andinus/octans&gt;


1 Demo
══════

  This was recorded with `asciinema(1)&#39;.

  [https://asciinema.org/a/384464.png]

  ⁃ Octans 2020-01-14: &lt;https://asciinema.org/a/384464&gt;
  ⁃ alt-link (download): &lt;https://andinus.nand.sh/static/octans&gt;


[https://asciinema.org/a/384464.png] &lt;https://asciinema.org/a/384464&gt;


2 Documentation
═══════════════

2.1 Implementation
──────────────────

  Initially it went over the list of words &amp; checked if they exist in
  the grid. This was very slow.

  Currently it walks the grid &amp; checks if the current string exist in
  the dictionary. This is faster for these reasons:

  • The dictionary is sorted, we perform binary range search on the
    dictionary to return the list of all words that start with specific
    string.
  • Starting positions are limited.

  If the dictionary wasn&#39;t sorted then this probably would&#39;ve been
  slower than previous implementation.


2.2 Options
───────────