#! perl

=head1 NAME

block-graphics-to-ascii - map block graphics to ascii characters

=head1 DESCRIPTION

A not very useful example of filtering all text output to the terminal
by replacing all line-drawing characters (U+2500 .. U+259F) by a
similar-looking ascii character.

=cut

# simple example that uses the add_lines hook to filter unicode and vt100 line/box graphics

#                  ─━│┃┄┅┆┇┈┉┊┋┌┍┎┏┐┑┒┓└┕┖┗┘┙┚┛├┝┞┟┠┡┢┣┤┥┦┧┨┩┪┫┬┭┮┯┰┱┲┳┴┵┶┷┸┹┺┻┼┽┾┿╀╁╂╃╄╅╆╇╈╉╊╋╌╍╎╏
my $rep_unicode = "--||--||--||++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--||"
#                  ═║╒╓╔╕╖╗╘╙╚╛╜╝╞╟╠╡╢╣╤╥╦╧╨╩╪╫╬╭╮╯╰╱╲ ╳╴╵╶╷╸╹╺╻╼╽╾╿▀▁▂▃▄▅▆▇█▉▊▋▌▍▎▏▐░▒▓▔▕▖▗▘▙▚▛▜▝▞▟
                . "=|+++++++++++++++++++++++++++++++/\\X-|-|-|-|-|-|#____#######|||||###~###########";

#              ↑↓→←█▚ ☃HIJKLMNOPQRSTUVWXYZ[\ ]^ ◆▒␉␌␍␊°±␤␋┘┐┌└┼⎺⎻─⎼⎽├┤┴┬│≤≥π≠£·
my $rep_acs = "↑↓<>#\\☃HIJKLMNOPQRSTUVWXYZ[\\]^ ◆#␉␌␍␊°±␤␋+++++⎺⎻-⎼⎽++++!<>π≠£·";

sub on_add_lines {
   my ($self, $str) = @_;

   $str =~ s/([\x{2500}-\x{259f}])/substr $rep_unicode, (ord $1) - 0x2500, 1/ge;

   $str =~ s/([\x41-\x7e])/substr $rep_acs, (ord $1) - 0x41, 1/ge
      if $self->cur_charset eq "0";

   $self->scr_add_lines ($str);

   1
}