#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# 
# Parses Khmer text, with orthographic syllable as token.
#
# The definition of Khmer orthographic syllable is taken from the Unicode Standard.
#
# B = base character (consonant, independent vowel, etc)
$KhmerBase = [\u1780-\u17B3];
# R = robat
$KhmerRobat = [\u17CC];
# C = consonant shifter
$KhmerShifter = [\u17C9\u17CA];
# S = subscript consonant or independent vowel sign
$KhmerSub = ([\u17D2] $KhmerBase);
# V = dependent vowel sign
$KhmerVowel = [\u17B4-\u17C5];
# Z = zero-width joiner or non-joiner
$KhmerZWC = [\u200C\u200D];
# O = any other sign
$KhmerSign = [\u17C6-\u17C8\u17CB\u17CD-\u17D1\u17DC\u17DD]; 

$WordJoin = [:Line_Break=Word_Joiner:];

$KhmerSyllableEx = $KhmerBase ($KhmerRobat | $KhmerShifter)? ($KhmerSub ($KhmerRobat)?)* (($KhmerZWC)? $KhmerVowel)? ($KhmerSign)? ($KhmerSub)?;

$KhmerJoinedSyllableEx = $KhmerSyllableEx ($WordJoin $KhmerSyllableEx)*;

#
# default numerical definitions
#
$Extend       = [\p{Word_Break = Extend}];
$Format       = [\p{Word_Break = Format}];
$MidNumLet    = [\p{Word_Break = MidNumLet}];
$MidNum       = [\p{Word_Break = MidNum}];
$Numeric      = [\p{Word_Break = Numeric}];
$ExtendNumLet = [\p{Word_Break = ExtendNumLet}];                                                          
$MidNumLetEx    = $MidNumLet    ($Extend |  $Format)*;
$MidNumEx       = $MidNum       ($Extend |  $Format)*;
$NumericEx      = $Numeric      ($Extend |  $Format)*;
$ExtendNumLetEx = $ExtendNumLet ($Extend |  $Format)*;

!!forward;
$KhmerJoinedSyllableEx {200};

# default numeric rules
$NumericEx $ExtendNumLetEx? (($MidNumEx | $MidNumLetEx)? $NumericEx $ExtendNumLetEx?)*  {100};