#!/usr/bin/ruby

ME="sl: "

$release=false
$git=false
$lpath=[]
$outfile=nil

def get_path(fn)
  if fn.start_with?("/")
    begin
      return fn if File.stat(fn).readable?
    rescue
    end
    return nil
  end
  for p in $lpath
    n=p+"/"+fn
    begin
      return File.expand_path(n) if File.stat(n).readable?
    rescue
    end
  end
  return nil
end

$loaded=[]
def load_file(buf,fn,_r=false)
  p=File.expand_path(fn)
  return if $loaded.include?(p)
  $loaded.push(p)
  begin
    f=File.open(fn,"r")
  rescue
    $stderr.puts ME+"unable to open file: "+fn
    exit 1
  end

  _ea=false
  _ed=false
  for l in f
    l.chop!
    if _ea
      _ea=false
      buf<<"" if not l.empty?
    end
    if _r
      if _ed
        _ed=false
        next if l.empty?
      end
      if /^[#\-\/\*][\-\/\*]? vim:/.match(l)
        _ed=true
        next
      end
    end
    if tmp=/^@\+ (.*)/.match(l)
      if !p=get_path(tmp[1])
        $stderr.puts ME+"file not found: "+tmp[1]
        f.close
        exit 1
      end
      load_file(buf,p,true)
      next
    end
    if tmp=/^@ (.*)/.match(l)
      if !p=get_path(tmp[1])
        $stderr.puts ME+"file not found: "+tmp[1]
        f.close
        exit 1
      end
      if $release
        load_file(buf,p,true)
        _ea=true
      else
        buf<<"load "+p.dump
      end
      next
    end
    buf<<l
  end
  f.close
end

def usage()
  me=ME.delete(":")
  $stderr.puts "Usage: "+me+"[-r] [-l <path>] -o <outfile> <file>"
  exit 1
end

i=0
while i<ARGV.length
  if ARGV[i]=="--"
    i=i+1
    break
  end
  break if ARGV[i]=="-"
  break if not ARGV[i].start_with?("-")

  usage if ARGV[i]=="--help"

  if ARGV[i]=="-r"
    i+=1
    $release=true
    next
  end
  if ARGV[i]=="-git"
    i+=1
    $git=true
    next
  end
  if ARGV[i]=="-l"
    i+=1
    if !ARGV[i]
      $stderr.puts ME+"Need argument for '-l' option"
      exit 1
    end
    $lpath.push(File.dirname(ARGV[i]+"/."))
    i+=1
    next
  end
  if ARGV[i]=="-o"
    i+=1
    if !ARGV[i]
      $stderr.puts ME+"Need argument for '-o' option"
      exit 1
    end
    $outfile=ARGV[i]
    i+=1
    next
  end
  $stderr.puts ME+"Unknown option: "+ARGV[i]
  exit 1
end

usage if !$outfile or !ARGV[i]
usage if $outfile.empty? or ARGV[i].empty?

buf=[]
load_file(buf,ARGV[i])
begin
  f=File.open($outfile,"w")
rescue
  $stderr.puts ME+"unable to open for writing: "+$outfile
  exit 1
end
gv=nil
for l in buf
  if $git and (/\$Format:%h\$/.match(l))
    if !gv
      gv=`git log -1 --pretty=%h HEAD`.chop
      tmp=`git status --short`.split("\n")
      gv+="-dirty" if tmp.length>0
    end
    l.sub!(/\$Format:%h\$/,gv)
  end
  f.puts l
end
f.close