#! /usr/bin/env python
###  Suggested usage: display the legend on the (root window) desktop,
###  by installing debian pkg "xrootconsole" and adding a line within session autostart file:
###      xrootconsole ~/.icewm/icekeys-legend.txt
###  (read the xrootconsole manpage! fontsize, color, x/y offset are configurable)
###      -or-
###  add a conky bit which monitors, and dynamically updates the legend
### ${execi watch -n 30 | cat ~/.icewm/icekeys-legend.txt | sort -r}
###  (can run multiple conky instances, but each adds 20MB? session overhead)
###
###  another utility, "root-tail" is similar/equivalent to "xrootconsole"

import os

lefty = []; righty = []; maxwidleft = 0; mydescription = ''; outtext = ''

### terse statement, but it works (presuming the file exists and is readable)
dalist = [line for line in open(os.path.expanduser('~/.icewm/keys'), "r").read().splitlines() if line]

for line in dalist:
    line = line.strip()
    pieces = line.split()
    if line.startswith('###    v--- desc: '):  ### chars0--17
        ''' TO DISPLAY A FRIENDLY DESCRIPTION IN PLACE OF EXECSTRING,
            THE keys FILE WOULD CONTAIN, FOR EXAMPLE:
        ###    v--- desc: decrease volume 5%
        key "Alt+Ctrl+KP_Divide" amixer -c 0 set Master 5-# lower volume
        '''
        mydescription = " " + str(line)[18:]
        continue

    ### a valid line must contain elements[0,1,2] and begin with "key"
    elif line.startswith('key') and line.split()[2]:
        if pieces[1].startswith('"') and pieces[1].endswith('"'):
            lefty.append( str(pieces[1])[1:-1].replace('+',' + ') )
            maxwidleft = max( len(str(pieces[1])) + 3, maxwidleft )
        else:
            continue   ### malformed line, so skip

        if mydescription != '':
            righty.append(mydescription)
        else:
            ###  How long is a piece of string?
            skip = len(str(pieces[0])) + len(str(pieces[1])) + 1
            ### discard any end-of-line comments
            righty.append( str(str(line[skip:]).partition('#')[0]) )

        mydescription = ''   # reset to blank after using

for i in range(len(righty)):
    myline = str(lefty[i]).rjust(maxwidleft) + " :" + str(righty[i])
    outtext = outtext + myline + "\n"

f = open(os.path.expanduser('~/.icewm/icekeys-legend.txt'), "w")
f.write(outtext)  ### creates, or overwrites existing
f.close()