#XPA (X Public Transport Access) in Python. (C) Andrew Williams, 2000, 2001
#  andrew@physics.uwa.edu.au
#
# or
#
#  andrew@longtable.org
#
import commands
import string
import os
import globals

viewer='ds9'      #Default to ds9 unless otherwise overriden


class marker:
  """Defines a class for storing SAO(tng/ds9) regions. Should work with any
     type that defined by x, y, and size (eg circle), only tested for points.
     Create an instance with:  m=xpa.marker(123.4, 345.6, 'lens'), for example.
  """
  def __init__(self,x=0,y=0,label='',type='point',size=0):
    self.x=x
    self.y=y
    self.label=label
    self.type=type
    self.size=size
  def display(self):   #Sends an XPA message to the viewer to show this marker
    if self.type=='point':  #Points don't have a size attribute
      if viewer=='SAOtng':
        cmd="regions '#"+self.label+"; "+self.type+" "+`self.x`+" "+`self.y`+"'"
        commands.getoutput('echo "'+cmd+'" | xpaset '+viewer)
      else:
        cmd="regions '"+self.type+" "+`self.x`+" "+`self.y`+" # text={"+self.label+"} '"
        commands.getoutput('echo '+cmd+' | xpaset '+viewer)
    print cmd


def deleteregions():
  """Send an XPA message to the viewer to delete all markers.
  """
  if viewer=='SAOtng':
    commands.getoutput('echo "regions delete" | xpaset '+viewer)
  else:
    commands.getoutput('echo "regions deleteall" | xpaset '+viewer)


def showmlist(mlist=[]):
  """When called with a list of markers, call the display method for
     each marker in the list.
  """
  for m in mlist:
    m.display()


def getregions():
  """Ask the viewer what regions are defined, parse the output, and 
     return a list of marker objects.
  """
  #Call the xpaget command, get the output, and split it into a list of lines
  if viewer=='ds9':
    out=string.split(commands.getoutput('xpaget ds9 regions'),'\n')
    label=''
    mlist=[]
    for r in out:       #For each line
      if r[0]=='#' or r[:6]=='global':
        pass
      else:
        sc=string.find(r,';')
        ob=string.find(r,'(')
        cb=string.find(r,')')
        type=r[sc+1:ob]     #type is the string between the ; and the (
        ocb=string.find(r,'{')
        ccb=string.find(r,'}')
        label=r[ocb+1:ccb]   #The label is between curly brackets
        if type=='point':
          x,y=eval(r[ob+1:cb])  #Grab the X and Y values for a point
          m=marker(x,y,label,type)  #Create a marker object
        else:
          x,y,size=eval(r[ob+1:cb]) #Grab X,Y, and Size for a circle, etc
          m=marker(x,y,label,type,size)  #Create a marker object
        mlist.append(m)   #Add the object to the list
    return mlist
  else:
    out=string.split(commands.getoutput('xpaget SAOtng regions'),'\n')
    label=''
    mlist=[]
    for r in out:       #For each line
      if r[0]=='#':     #This line is a label that refers to the next region
        label=r[1:]
      else:
        ob=string.find(r,'(')
        cb=string.find(r,')')
        type=r[1:ob]     #type is the string between the leading + and the (
        if type=='point':
          x,y=eval(r[ob+1:cb])  #Grab the X and Y values for a point
          m=marker(x,y,label,type)  #Create a marker object
        else:
          x,y,size=eval(r[ob+1:cb]) #Grab X,Y, and Size for a circle, etc
          m=marker(x,y,label,type,size)  #Create a marker object
        label=''     #Clear label so it won't get attached to the next marker
        mlist.append(m)   #Add the object to the list
    return mlist


def _displayfile(fname, iraf=0):
  """Usage: display(fname, iraf=0)
     Send an image to SAOtng or DS9 for display - if iraf=1 then send in 8-bit
     IRAF format.
  """
  fullfilename=os.path.abspath(os.path.expanduser(fname))
  if iraf:
    os.system('/usr/local/dts/bin/display '+fullfilename)
  else:
    os.system('echo file '+fullfilename+' | xpaset '+viewer)
    os.system('echo orient y | xpaset '+viewer)
    if viewer=='ds9':
      os.system('echo scale zscale | xpaset '+viewer)
    else:
      os.system('echo scale histeq | xpaset '+viewer)


def display(fpat, iraf=0):
  """Display the specified file/s on the viewer program (eg SAOtng).
      If no filename is given, display the last image taken.
      if iraf=1 then the image is displayed in 8-bit IRAF format (so 'imexam'
      will work)
      eg: display('/data/junk001.fits')
          display('/data/junk002.fits',iraf=1)
          display( reduce('/data/comet*.fits') )
          display()
  """
  globals.distribute(fpat,_displayfile,iraf)