# This script converts the data set from the `Text::Unidecode` Perl module into
# Rust code that creates a compile-time hash map. Empty strings are omitted from
# the map to save space, as `rust-unidecode` automatically transliterates
# unknown characters as empty strings.
#
# The Rust code is printed to standard output for convenience, so it will need
# to be piped into a file.
#
# Example usage:
#     perl generate_map.pl > ../src/data.rs

use strict;
use warnings;
use utf8;
use Text::Unidecode;

if ($Text::Unidecode::VERSION ne "1.30") {
  print("Text::Unidecode v1.30 is not installed.\n");
  exit 1
}

print("// File autogenerated with /scripts/generate_map.pl\n\n");
print("pub static MAPPING: [&'static str; 0xffff] = [\n");
for (my $i = 0; $i < 0xffff; $i++) {
    # Verify that number is valid Unicode
    if (($i < 0 || $i > 0xD7FF) && ($i < 0xE000 || $i > 0x10FFFF)) {
        print("    \"\",\n");
        next;
    }

    my $v = "\"";
    my $ch = '';
    foreach $ch (split //, unidecode(chr($i))) {
        $v .= "\\u\{" . sprintf("%x", ord($ch)) . "\}";
    }
    $v .= "\"";
    print("    $v,\n");
}
print("];\n");