#!/usr/bin/env ruby
# slf
#  -- simple line formater
#  NISHI Takao <zophos@koka-in.org>
#
#  Time-stamp: <2002/05/29 12:05:54 zophos>
#
require 'jcode'
require 'kconv'

$KCODE='euc'

DEFAULT_FILL=76
DEFAULT_HANG_CHAR=['\,','.','，','．','、','。',
    ')','}',']','）','」','』',10.chr,13.chr]
DEFAULT_EXPEL_CHAR=['(','{','[','（','「','『']
DEFAULT_HANG_DEPTH=2

def usage
    print <<EOS
slf [option] [file]
options:
 -l  : line length(bytes)
 -ec : expel chars for prohibition
 -hc : hang chars for prohibition
 -hd : hang depth
 -ne : turn off expeling
 -nh : turn off hanging
 -np : turn off prohibition
 -h, --help : show this message 
EOS
    exit
end

file=nil
maxlen=DEFAULT_FILL
hang_chars=DEFAULT_HANG_CHAR
expel_chars=DEFAULT_EXPEL_CHAR
maxhangdepth=DEFAULT_HANG_DEPTH
prohibition=true

arg=ARGV.shift
until(arg.nil?)
    case arg
    when '-l'
	maxlen=ARGV.shift.to_i
    when '-hc'
	hang_chars=ARGV.shift.to_s.split(//)
    when '-ec'
	expel_chars=ARGV.shift.to_s.split(//)
    when '-hd'
	maxhangdepth=ARGV.shift.to_i
    when '-nh'
	hang_chars=[]
    when '-ne'
	expel_chars=[]
    when '-np'
	hang_chars=[]
	expel_chars=[]
    when '-h','--help'
	usage
    else
	file=arg
    end
    arg=ARGV.shift
end

maxlen-=1
if(maxlen<0)
    maxlen=DEFAULT_FILL
end
unless(hang_chars.instance_of?(Array))
    hang_chars=[]
end
unless(expel_chars.instance_of?(Array))
    expel_chars=[]
end

if(file.nil?)
    file=STDIN
else
    file=open(file)
end

begin
    file.readlines.each{|line|
	src=Kconv::toeuc(line).split(//)
	c=src.shift
	dst=''
	hd=0
	until(c.nil?)
	    if(dst.size>=maxlen)
		tmp=dst.split(//)
		unless(expel_chars.index(tmp[-1]).nil?)
		    src.unshift(c)
		    c=tmp.pop
		    dst=tmp.join('')
		end
		
		if((hang_chars.index(c).nil?)||(hd>maxhangdepth))
		    puts dst
		    dst=''
		    hd=0
		else
		    hd+=1
		end
	    end
	    
	    dst+=c.to_s
	    c=src.shift
	end
	unless(dst.empty?)
	    puts dst
	end
    }
rescue
ensure
    file.close
end