import tempfile
import sys
import os
import stat

from Patch import Patch, PatchSeries

class DiffGzException(Exception):
  pass

class DiffGzHandler:
  diff = None
  def __init__(self,fname):
    self.diff = fname
    self.size = os.stat(fname)[stat.ST_SIZE]

  def filterdiff(self, include=None, exclude=None, ghost=False):
    cmd = ["filterdiff","-z","-p","1"]
    if include:
      cmd += [ "-i", include]
    elif exclude:
      cmd += [ "-x", exclude]
    else:
      raise Exception("DiffGzHandler.filterdiff called w/o include/exclude")
    i,o,e=os.popen3(cmd+[self.diff])
    i.close()
    p = Patch(o, ghost=ghost)
    o.close()
    err = e.read()
    if len(err):
      raise DiffGzException("filterdiff gave errors: "+err)
    return p

  def debiandir(self):
    return self.filterdiff(include='debian/*')

  def nondebiandir(self, ghost=False):
    return self.filterdiff(exclude='debian/*', ghost=ghost)

  def series(self, ghost=False):
    patches = None

    # XXX *cough* cache *cough*
    td = tempfile.mkdtemp()
    i,o,e=os.popen3("filterdiff -z -p 1 -i 'debian/patches*' %s | patch -d %s -p3" % (self.diff, td))
    o.close()
    i.close()
    err = e.read()
    if len(err):
      raise Exception("unable to extract series patches:\n"+err)
    patches = PatchSeries(td, ghost=ghost)
    os.system("rm -rf %s"%(td))

    return patches
  
if __name__ == "__main__":
  print "DiffGzHandler testing"
  try:
    dh = DiffGzHandler(sys.argv[1])
  except IndexError:
    print "usage: %s <diffgz>"%(sys.argv[0])
    sys.exit(1)

  print "debian dir:"
  print dh.debiandir().diffstat()
  print "nondebian dir:"
  print dh.nondebiandir().diffstat()
  print "series:"
  s = dh.series()
  print s
  for name,patch in s.iterpatches():
    print "patch:",name
    print patch.diffstat()