switcher.py

import os.path
import string
import pickle
import subprocess
import sys

wmctrl_columns = {'id': 0, 'desktop': 1, 'wm_class': 2, 'host': 3, 'title': 4}
tmp_last_active_window_file = "/tmp/wmctrl-cycle.pickle"

if (len(sys.argv) != 2):
    print "Usage: python switcher.py window_pattern."
    print "Example: python switcher.py sublime_text."
    exit(1);
in_pattern = sys.argv[1].lower().strip()


proc = subprocess.Popen(["wmctrl", "-l", "-x"], stdout=subprocess.PIPE, shell=False)
(out, err) = proc.communicate()
xwindows = string.split(out, '\n')

# Get active windows from xprop
proc = subprocess.Popen(["xprop", "-root", "_NET_ACTIVE_WINDOW"], stdout=subprocess.PIPE, shell=False)
(out, err) = proc.communicate()
active_xid = string.split(out)[4][2:]

# Load information about last open windows for in_patterns
app_last_active_window_of_apps = dict()
if (os.path.isfile(tmp_last_active_window_file)):
    with open(tmp_last_active_window_file, 'rb') as handle:
        app_last_active_window_of_apps = pickle.loads(handle.read())
        # print "app_last_active_window_of_apps", app_last_active_window_of_apps

# Filter all xwindows to find active window and all matched windows
app_matched_xwindows = list()
app_curr_active_window = False
active_window_matched = -1
for i,xwin in enumerate(xwindows):
    if (not xwin):
        continue
    # Get the X id, WM_CLASS and title of the X window
    xdata = string.split(xwin, maxsplit=4)
    xid = xdata[wmctrl_columns['id']]
    desktop = xdata[wmctrl_columns['desktop']]
    wmclass = xdata[wmctrl_columns['wm_class']].lower()
    title = xdata[wmctrl_columns['title']].lower()
    
    # Discard invalid desktop
    if (desktop == "-1"):
        continue

    # Matched window by title or by wmclass
    matched = False
    if (title.find(in_pattern) >= 0 or wmclass.find(in_pattern) >= 0):
        app_matched_xwindows.append(xid)
        matched = True

    # Check if this is the active window
    # Note we make sure the match is at the rightmost position, since the hexa string returned by xprop (active_xid)
    # is not 0-padded, unlike the string from wmctrl
    if (xid.rfind(active_xid) + len(active_xid) == len(xid)):
        active_xid = xid
        app_curr_active_window = xid
        if (matched):
            active_window_matched = len(app_matched_xwindows) - 1


print "---------"
print "app_matched_xwindows", app_matched_xwindows
print "app_curr_active_window", app_curr_active_window
print "app_last_active_window_of_apps", app_last_active_window_of_apps
print "active_window_matched", active_window_matched

# No windows matched, nowhere to switch to
if (not app_matched_xwindows):
    print "No xwindow matched the query."
    to_activate = False
# If the active window is in the list of matched windows, activate the next one in the list
elif (active_window_matched >= 0):
    if (len(app_matched_xwindows) == 1):
        print "The only matched window is active."
        to_activate = False
    else:
        print "Cycling from window", app_matched_xwindows[active_window_matched], "to", app_matched_xwindows[(active_window_matched+1)%len(app_matched_xwindows)]
        to_activate = app_matched_xwindows[(active_window_matched+1)%len(app_matched_xwindows)]
# Otherwise active the last window active for given in_pattern
else:
    if (in_pattern in app_last_active_window_of_apps):
        to_activate = app_last_active_window_of_apps[in_pattern]
        if (not to_activate in app_matched_xwindows):
            print "Last window that was active for pattern:",in_pattern,"not open anymore."
            del(app_last_active_window_of_apps[in_pattern])
            print "Activating first window of all the matched windows."
            to_activate = app_matched_xwindows[0]
        else:
            print "Activating last window that was active for pattern:",in_pattern
    else:
        print "Activating first window of all the matched windows."
        to_activate = app_matched_xwindows[0]

# Add the window we switch to in the list of last active windows
if (to_activate):
    app_last_active_window_of_apps[in_pattern] = to_activate

# Save information about last open windows for in_patterns
with open(tmp_last_active_window_file, 'wb') as handle:
    pickle.dump(app_last_active_window_of_apps, handle)

# Switch focus to appropriate window
if (to_activate):
    print "---------"
    print "wmctrl -i -a", to_activate
    proc = subprocess.Popen(["wmctrl", "-i", "-a", to_activate], stdout=subprocess.PIPE, shell=False)
    (out, err) = proc.communicate()