#!/usr/bin/perl -w

use warnings;
use strict;

my $HASHBUCKETS1_16 = 256;
my $HASHBUCKETS1_32 = 16;
my $HASHBUCKETS2_16 = 16;
my $HASHBUCKETS3_16 = 4;

my $mem_used = 0;

print <<__EOF__;
/*
 * This file is part of PhysicsFS (https://icculus.org/physfs/)
 *
 * This data generated by physfs/extras/makecasefoldhashtable.pl ...
 * Do not manually edit this file!
 *
 * Please see the file LICENSE.txt in the source's root directory.
 */

#ifndef _INCLUDE_PHYSFS_CASEFOLDING_H_
#define _INCLUDE_PHYSFS_CASEFOLDING_H_

#ifndef __PHYSICSFS_INTERNAL__
#error Do not include this header from your applications.
#endif

/* We build three simple hashmaps here: one that maps Unicode codepoints to
a one, two, or three lowercase codepoints. To retrieve this info: look at
case_fold_hashX, where X is 1, 2, or 3. Most foldable codepoints fold to one,
a few dozen fold to two, and a handful fold to three. If the codepoint isn't
in any of these hashes, it doesn't fold (no separate upper and lowercase).

Almost all these codepoints fit into 16 bits, so we hash them as such to save
memory. If a codepoint is > 0xFFFF, we have separate hashes for them,
since there are (currently) only about 120 of them and (currently) all of them
map to a single lowercase codepoint. */

typedef struct CaseFoldMapping1_32
{
    PHYSFS_uint32 from;
    PHYSFS_uint32 to0;
} CaseFoldMapping1_32;

typedef struct CaseFoldMapping1_16
{
    PHYSFS_uint16 from;
    PHYSFS_uint16 to0;
} CaseFoldMapping1_16;

typedef struct CaseFoldMapping2_16
{
    PHYSFS_uint16 from;
    PHYSFS_uint16 to0;
    PHYSFS_uint16 to1;
} CaseFoldMapping2_16;

typedef struct CaseFoldMapping3_16
{
    PHYSFS_uint16 from;
    PHYSFS_uint16 to0;
    PHYSFS_uint16 to1;
    PHYSFS_uint16 to2;
} CaseFoldMapping3_16;

typedef struct CaseFoldHashBucket1_16
{
    const CaseFoldMapping1_16 *list;
    const PHYSFS_uint8 count;
} CaseFoldHashBucket1_16;

typedef struct CaseFoldHashBucket1_32
{
    const CaseFoldMapping1_32 *list;
    const PHYSFS_uint8 count;
} CaseFoldHashBucket1_32;

typedef struct CaseFoldHashBucket2_16
{
    const CaseFoldMapping2_16 *list;
    const PHYSFS_uint8 count;
} CaseFoldHashBucket2_16;

typedef struct CaseFoldHashBucket3_16
{
    const CaseFoldMapping3_16 *list;
    const PHYSFS_uint8 count;
} CaseFoldHashBucket3_16;

__EOF__


my @foldPairs1_16;
my @foldPairs2_16;
my @foldPairs3_16;
my @foldPairs1_32;

for (my $i = 0; $i < $HASHBUCKETS1_16; $i++) {
    $foldPairs1_16[$i] = '';
}

for (my $i = 0; $i < $HASHBUCKETS1_32; $i++) {
    $foldPairs1_32[$i] = '';
}

for (my $i = 0; $i < $HASHBUCKETS2_16; $i++) {
    $foldPairs2_16[$i] = '';
}

for (my $i = 0; $i < $HASHBUCKETS3_16; $i++) {
    $foldPairs3_16[$i] = '';
}

open(FH,'<','casefolding.txt') or die("failed to open casefolding.txt: $!\n");
while (<FH>) {
    chomp;
    # strip comments from textfile...
    s/\#.*\Z//;

    # strip whitespace...
    s/\A\s+//;
    s/\s+\Z//;

    next if not /\A([a-fA-F0-9]+)\;\s*(.)\;\s*(.+)\;/;
    my ($code, $status, $mapping) = ($1, $2, $3);

    my $hexxed = hex($code);
    #print("// code '$code'   status '$status'   mapping '$mapping'\n");

    if (($status eq 'C') or ($status eq 'F')) {
        my ($map1, $map2, $map3) = (undef, undef, undef);
        $map1 = $1 if $mapping =~ s/\A([a-fA-F0-9]+)(\s*|\Z)//;
        $map2 = $1 if $mapping =~ s/\A([a-fA-F0-9]+)(\s*|\Z)//;
        $map3 = $1 if $mapping =~ s/\A([a-fA-F0-9]+)(\s*|\Z)//;
        die("mapping space too small for '$code'\n") if ($mapping ne '');
        die("problem parsing mapping for '$code'\n") if (not defined($map1));

        if ($hexxed < 128) {
            # Just ignore these, we'll handle the low-ASCII ones ourselves.
        } elsif ($hexxed > 0xFFFF) {
            # We just need to add the 32-bit 2 and/or 3 codepoint maps if this die()'s here.
            die("Uhoh, a codepoint > 0xFFFF that folds to multiple codepoints! Fixme.") if defined($map2);
            my $hashed = (($hexxed ^ ($hexxed >> 8)) & ($HASHBUCKETS1_32-1));
            #print("// hexxed '$hexxed'  hashed1 '$hashed'\n");
            $foldPairs1_32[$hashed] .= "    { 0x$code, 0x$map1 },\n";
            $mem_used += 8;
        } elsif (not defined($map2)) {
            my $hashed = (($hexxed ^ ($hexxed >> 8)) & ($HASHBUCKETS1_16-1));
            #print("// hexxed '$hexxed'  hashed1 '$hashed'\n");
            $foldPairs1_16[$hashed] .= "    { 0x$code, 0x$map1 },\n";
            $mem_used += 4;
        } elsif (not defined($map3)) {
            my $hashed = (($hexxed ^ ($hexxed >> 8)) & ($HASHBUCKETS2_16-1));
            #print("// hexxed '$hexxed'  hashed2 '$hashed'\n");
            $foldPairs2_16[$hashed] .= "    { 0x$code, 0x$map1, 0x$map2 },\n";
            $mem_used += 6;
        } else {
            my $hashed = (($hexxed ^ ($hexxed >> 8)) & ($HASHBUCKETS3_16-1));
            #print("// hexxed '$hexxed'  hashed3 '$hashed'\n");
            $foldPairs3_16[$hashed] .= "    { 0x$code, 0x$map1, 0x$map2, 0x$map3 },\n";
            $mem_used += 8;
        }
    }
}
close(FH);

for (my $i = 0; $i < $HASHBUCKETS1_16; $i++) {
    $foldPairs1_16[$i] =~ s/,\n\Z//;
    my $str = $foldPairs1_16[$i];
    next if $str eq '';
    my $num = '000' . $i;
    $num =~ s/\A.*?(\d\d\d)\Z/$1/;
    my $sym = "case_fold1_16_${num}";
    print("static const CaseFoldMapping1_16 ${sym}[] = {\n$str\n};\n\n");
}

for (my $i = 0; $i < $HASHBUCKETS1_32; $i++) {
    $foldPairs1_32[$i] =~ s/,\n\Z//;
    my $str = $foldPairs1_32[$i];
    next if $str eq '';
    my $num = '000' . $i;
    $num =~ s/\A.*?(\d\d\d)\Z/$1/;
    my $sym = "case_fold1_32_${num}";
    print("static const CaseFoldMapping1_32 ${sym}[] = {\n$str\n};\n\n");
}

for (my $i = 0; $i < $HASHBUCKETS2_16; $i++) {
    $foldPairs2_16[$i] =~ s/,\n\Z//;
    my $str = $foldPairs2_16[$i];
    next if $str eq '';
    my $num = '000' . $i;
    $num =~ s/\A.*?(\d\d\d)\Z/$1/;
    my $sym = "case_fold2_16_${num}";
    print("static const CaseFoldMapping2_16 ${sym}[] = {\n$str\n};\n\n");
}

for (my $i = 0; $i < $HASHBUCKETS3_16; $i++) {
    $foldPairs3_16[$i] =~ s/,\n\Z//;
    my $str = $foldPairs3_16[$i];
    next if $str eq '';
    my $num = '000' . $i;
    $num =~ s/\A.*?(\d\d\d)\Z/$1/;
    my $sym = "case_fold3_16_${num}";
    print("static const CaseFoldMapping3_16 ${sym}[] = {\n$str\n};\n\n");
}

print("static const CaseFoldHashBucket1_16 case_fold_hash1_16[] = {\n");

for (my $i = 0; $i < $HASHBUCKETS1_16; $i++) {
    my $str = $foldPairs1_16[$i];
    if ($str eq '') {
        print("    { NULL, 0 },\n");
    } else {
        my $num = '000' . $i;
        $num =~ s/\A.*?(\d\d\d)\Z/$1/;
        my $sym = "case_fold1_16_${num}";
        print("    { $sym, __PHYSFS_ARRAYLEN($sym) },\n");
    }
    $mem_used += 12;
}
print("};\n\n");


print("static const CaseFoldHashBucket1_32 case_fold_hash1_32[] = {\n");

for (my $i = 0; $i < $HASHBUCKETS1_32; $i++) {
    my $str = $foldPairs1_32[$i];
    if ($str eq '') {
        print("    { NULL, 0 },\n");
    } else {
        my $num = '000' . $i;
        $num =~ s/\A.*?(\d\d\d)\Z/$1/;
        my $sym = "case_fold1_32_${num}";
        print("    { $sym, __PHYSFS_ARRAYLEN($sym) },\n");
    }
    $mem_used += 12;
}
print("};\n\n");


print("static const CaseFoldHashBucket2_16 case_fold_hash2_16[] = {\n");

for (my $i = 0; $i < $HASHBUCKETS2_16; $i++) {
    my $str = $foldPairs2_16[$i];
    if ($str eq '') {
        print("    { NULL, 0 },\n");
    } else {
        my $num = '000' . $i;
        $num =~ s/\A.*?(\d\d\d)\Z/$1/;
        my $sym = "case_fold2_16_${num}";
        print("    { $sym, __PHYSFS_ARRAYLEN($sym) },\n");
    }
    $mem_used += 12;
}
print("};\n\n");

print("static const CaseFoldHashBucket3_16 case_fold_hash3_16[] = {\n");

for (my $i = 0; $i < $HASHBUCKETS3_16; $i++) {
    my $str = $foldPairs3_16[$i];
    if ($str eq '') {
        print("    { NULL, 0 },\n");
    } else {
        my $num = '000' . $i;
        $num =~ s/\A.*?(\d\d\d)\Z/$1/;
        my $sym = "case_fold3_16_${num}";
        print("    { $sym, __PHYSFS_ARRAYLEN($sym) },\n");
    }
    $mem_used += 12;
}
print("};\n\n");

print <<__EOF__;

#endif  /* _INCLUDE_PHYSFS_CASEFOLDING_H_ */

/* end of physfs_casefolding.h ... */

__EOF__

print STDERR "Memory required for case-folding hashtable: $mem_used bytes\n";

exit 0;

# end of makecashfoldhashtable.pl ...