Adding help and autocompletion.

Build.PL

@@ -8,6 +8,7 @@ my $build = Module::Build->new(
     requires => {
         'Mojolicious' => 0,
         'JSON' => 0,
+        'Const::Fast' => 0,
     },
 );
 $build->create_build_script;

bin/tdtcli.pl

@@ -9,11 +9,43 @@ use Data::Dumper;
 use Term::ReadLine;
 use FileHandle;
 
+use Const::Fast;
 use Mojo::UserAgent;
 use JSON;
 
 binmode STDOUT, ':utf8';
 
+const my $COMMANDS => {
+    countries => {
+        description => 'List available countries.',
+        action      => \&show_countries,
+    },
+    select_country => {
+        description => 'Select a country.',
+        action      => \&select_country
+    },
+    ambits => {
+        description => 'List available ambits.',
+        action      => \&show_ambits
+    },
+    select_ambit => {
+        description => 'Select a ambit.',
+        action      => \&select_ambit
+    },
+    channnels => {
+        description => 'List available channels.',
+        action      => \&show_channels
+    },
+    select_channel => {
+        description => 'Select a channel.',
+        action      => \&select_channel
+    },
+    help => {
+        description => 'Show this help.',
+        action      => \&show_help
+    }
+};
+
 my $ua           = Mojo::UserAgent->new;
 my $tdt_channels = decode_json(
     $ua->get('https://www.tdtchannels.com/lists/tv.json')->result->body );
@@ -23,10 +55,13 @@ my $countries = $tdt_channels->{countries};
 my $selected_country;
 my $selected_ambit;
 
-my $term = Term::ReadLine->new('tdtcli');
+my $term    = Term::ReadLine->new('tdtcli');
+my $attribs = $term->Attribs;
+$attribs->{completion_entry_function} = $attribs->{list_completion_function};
+$attribs->{completion_word}           = [ keys %$COMMANDS ];
 
 while ( defined( my $line = $term->readline('~> ') ) ) {
-    proccess_line($line);
+    process_line($line);
     $term->addhistory($line);
 
     if ( defined $selected_country ) {
@@ -38,29 +73,34 @@ while ( defined( my $line = $term->readline('~> ') ) ) {
     }
 }
 
-sub proccess_line {
+sub process_line {
     my $line = shift;
     return unless defined $line;
     my @line = split /\s+/, $line;
     return unless defined $line[0];
     my $command = shift @line;
-    show_countries()          if $command eq 'countries';
-    select_country( [@line] ) if $command eq 'select_country';
-    show_ambits()             if $command eq 'ambits';
-    select_ambit( [@line] )   if $command eq 'select_ambit';
-    show_channels()           if $command eq 'channels';
-    select_channel( [@line] ) if $command eq 'select_channel';
+    say("No such command $command."), return
+      unless exists $COMMANDS->{$command};
+    $COMMANDS->{$command}{action}->( [@line] );
+}
+
+sub show_help {
+    say <<'EOF';
+TDTCli help page:
+EOF
+    for my $command ( sort { $a cmp $b } keys %$COMMANDS ) {
+        say "$command : $COMMANDS->{$command}{description}";
+    }
 }
 
 sub select_channel {
     my $arguments = shift;
+    say('You must first select a ambit with select_ambit'), return
+      unless defined $selected_ambit;
     say('You must pass a channel number.'), return
       unless exists $arguments->[0];
     my $channel = $arguments->[0];
     return unless $channel =~ /^\d+$/;
-    say('You must first select a ambit with /select_ambit'),
-      return undef $selected_ambit
-      unless defined $selected_ambit;
     my $ambits                  = $countries->[$selected_country]{ambits};
     my $channels                = $ambits->[$selected_ambit]{channels};
     my $current_channel_options = $channels->[$channel]{options};
@@ -78,7 +118,7 @@ sub select_channel {
 }
 
 sub show_channels {
-    say('You must first select a ambit with /select_ambit'), return
+    say('You must first select a ambit with select_ambit'), return
       unless defined $selected_ambit;
     my $names =
       [ map { $_->{name} }
@@ -93,24 +133,24 @@ sub show_channels {
 
 sub select_ambit {
     my $arguments = shift;
-    say('You must first select a country with /select_country'), return
+    say('You must first select a country with select_country'), return
       unless defined $selected_country;
-    say('No ambit passed see /ambits'), return
+    say('No ambit passed see ambits'), return
       unless defined $arguments->[0];
     my $ambit = $arguments->[0];
     return unless $ambit =~ /^\d+$/;
-    say('Such ambit doesn\'t exists see /ambits'), return
+    say('Such ambit doesn\'t exists see ambits'), return
       unless exists $countries->[$selected_country]{ambits}[$ambit];
     $selected_ambit = $ambit;
 }
 
 sub select_country {
     my $arguments = shift;
-    say('No country passed see /countries'), return
+    say('No country passed see countries'), return
       unless defined $arguments->[0];
     my $country = $arguments->[0];
     return unless $country =~ /^\d+$/;
-    say('Such country doesn\'t exists see /countries'), return
+    say('Such country doesn\'t exists see countries'), return
       if !exists $countries->[$country];
     $selected_country = $country;
     undef $selected_ambit;