# -*- coding: utf-8 -*-
"""
Various utilities

Authors: Ed Rousseau <rousseau@redhat.com>, Zack Cerza <zcerza@redhat.com, David Malcolm <dmalcolm@redhat.com>
"""

__author__ = """Ed Rousseau <rousseau@redhat.com>,
Zack Cerza <zcerza@redhat.com,
David Malcolm <dmalcolm@redhat.com>
"""

import os
import sys
import subprocess
import re
import cairo
from gi.repository import Gtk
from gi.repository import GObject
from config import config
from time import sleep
from logging import debugLogger as logger
from logging import TimeStamp
from errors import DependencyNotFoundError

def screenshot(file = 'screenshot.png', timeStamp = True):
    """
    This function wraps the ImageMagick import command to take a screenshot.

    The file argument may be specified as 'foo', 'foo.png', or using any other
    extension that ImageMagick supports. PNG is the default.

    By default, screenshot filenames are in the format of foo_YYYYMMDD-hhmmss.png .
    The timeStamp argument may be set to False to name the file foo.png.
    """
    if not isinstance(timeStamp, bool):
        raise TypeError, "timeStampt must be True or False"
    # config is supposed to create this for us. If it's not there, bail.
    assert os.path.isdir(config.scratchDir)

    baseName = ''.join(file.split('.')[0:-1])
    fileExt = file.split('.')[-1].lower()
    if not baseName:
        baseName = file
        fileExt = 'png'

    if timeStamp:
        ts = TimeStamp()
        newFile = ts.fileStamp(baseName) + '.' + fileExt
        path = config.scratchDir + newFile
    else:
        newFile = baseName + '.' + fileExt
        path = config.scratchDir + newFile

    from gi.repository import Gdk
    from gi.repository import GObject
    from gi.repository import GdkPixbuf
    rootWindow = Gdk.get_default_root_window()
    geometry = rootWindow.get_geometry()
    pixbuf = GdkPixbuf.Pixbuf(colorspace=GdkPixbuf.Colorspace.RGB,
                              has_alpha=False,
                              bits_per_sample=8,
                              width=geometry[2],
                              height=geometry[3])

    pixbuf = Gdk.pixbuf_get_from_window(rootWindow, 0, 0, \
                                        geometry[2], geometry[3])
    # GdkPixbuf.Pixbuf.save() needs 'jpeg' and not 'jpg'
    if fileExt == 'jpg': fileExt = 'jpeg'
    try:
        pixbuf.savev(path, fileExt, [], [])
    except GObject.GError:
        raise ValueError, "Failed to save screenshot in %s format" % fileExt
    assert os.path.exists(path)
    logger.log("Screenshot taken: " + path)
    return path

def run(string, timeout=config.runTimeout, interval=config.runInterval, desktop=None, dumb=False, appName=''):
    """
    Runs an application. [For simple command execution such as 'rm *', use os.popen() or os.system()]
    If dumb is omitted or is False, polls at interval seconds until the application is finished starting, or until timeout is reached.
    If dumb is True, returns when timeout is reached.
    """
    if not desktop: from tree import root as desktop
    args = string.split()
    name = args[0]
    os.environ['GTK_MODULES'] = 'gail:atk-bridge'
    pid = subprocess.Popen(args, env = os.environ).pid

    if not appName:
        appName=args[0]

    if dumb:
        # We're starting a non-AT-SPI-aware application. Disable startup detection.
        doDelay(timeout)
    else:
        # Startup detection code
        # The timing here is not totally precise, but it's good enough for now.
        time = 0
        while time < timeout:
            time = time + interval
            try:
                for child in desktop.children[::-1]:
                    if child.name == appName:
                        for grandchild in child.children:
                            if grandchild.roleName == 'frame':
                                from procedural import focus
                                focus.application.node = child
                                doDelay(interval)
                                return pid
            except AttributeError: pass
            doDelay(interval)
    return pid

def doDelay(delay=None):
    """
    Utility function to insert a delay (with logging and a configurable
    default delay)
    """
    if delay is None:
        delay = config.defaultDelay
    if config.debugSleep:
        logger.log("sleeping for %f" % delay)
    sleep(delay)

class Highlight (Gtk.Window):

    def __init__(self, x, y, w, h):
        super(Highlight, self).__init__()
        self.set_decorated(False)
        self.set_has_resize_grip(False)
        self.set_default_size(w, h)
        self.screen = self.get_screen()
        self.visual = self.screen.get_rgba_visual()
        if self.visual is not None and self.screen.is_composited():
            self.set_visual(self.visual)
        self.set_app_paintable(True)
        self.connect("draw", self.area_draw)
        self.show_all()
        self.move(x,y)

    def area_draw(self, widget, cr):
        cr.set_source_rgba(.0, .0, .0, 0.0)
        cr.set_operator(cairo.OPERATOR_SOURCE)
        cr.paint()
        cr.set_operator(cairo.OPERATOR_OVER)
        cr.set_source_rgb(0.9, 0.1, 0.1)
        cr.set_line_width(6)
        cr.rectangle(0, 0, self.get_size()[0], self.get_size()[1])
        cr.stroke()

class Blinker(object):
    INTERVAL_MS = 1000
    main_loop = GObject.MainLoop()
    def __init__(self, x, y, w, h):
        from gi.repository import Gdk
        self.highlight_window = Highlight(x, y, w, h)
        if self.highlight_window.screen.is_composited() is not False:
            self.timeout_handler_id = GObject.timeout_add (Blinker.INTERVAL_MS, self.destroyHighlight)
            self.main_loop.run()
        else:
            self.highlight_window.destroy()

    def destroyHighlight(self):
        self.highlight_window.destroy()
        self.main_loop.quit()
        return False
        
class Lock(object):
    """
    A mutex implementation that uses atomicity of the mkdir operation in UNIX-like
    systems. This can be used by scripts to provide for mutual exlusion, either in single
    scripts using threads etc. or i.e. to handle sitations of possible collisions among
    multiple running scripts. You can choose to make randomized single-script wise locks
    or a more general locks if you do not choose to randomize the lockdir name
    """
    def __init__(self, location='/tmp', lockname='dogtail_lockdir_', randomize=True):
        """
        You can change the default lockdir location or name. Setting randomize to
        False will result in no random string being appened to the lockdir name.
        """
        self.lockdir = os.path.join(os.path.normpath(location), lockname)
        if randomize:
            self.lockdir = "%s%s" % (self.lockdir,self.__getPostfix())

    def lock(self):
        """
        Creates a lockdir based on the settings on Lock() instance creation.
        Raises OSError exception of the lock is already present. Should be
        atomic on POSIX compliant systems. 
        """
        locked_msg = 'Dogtail lock: Already locked with the same lock'
        if not os.path.exists(self.lockdir):
            try:
                os.mkdir(self.lockdir)
                return self.lockdir
            except OSError, e:
                if e.errno == errno.EEXIST and os.path.isdir(self.lockdir):
                    raise OSError(locked_msg)
        else:
            raise OSError(locked_msg)

    def unlock(self):
        """
        Removes a lock. Will raise OSError exception if the lock was not present.
        Should be atomic on POSIX compliant systems.
        """
        import os #have to import here for situations when executed from __del__
        if os.path.exists(self.lockdir):
            try:
                os.rmdir(self.lockdir)
            except OSError, e:
                if e.erron == errno.EEXIST:
                    raise OSError('Dogtail unlock: lockdir removed elsewhere!')
        else:
            raise OSError('Dogtail unlock: not locked')

    def __del__(self):
        """
        Makes sure lock is removed when the process ends. Although not when killed indeed.
        """
        self.unlock()

    def __getPostfix(self):
        import random
        import string
        return ''.join(random.choice(string.letters + string.digits) for x in range(5))
        

a11yDConfKey = 'org.gnome.desktop.interface'

def isA11yEnabled():
    """
    Checks if accessibility is enabled via DConf.
    """
    from gi.repository.Gio import Settings
    InterfaceSettings = Settings(a11yDConfKey)
    dconfEnabled = InterfaceSettings.get_boolean('toolkit-accessibility')
    if os.environ.get('GTK_MODULES','').find('gail:atk-bridge') == -1:
        envEnabled = False
    else: envEnabled = True
    return (dconfEnabled or envEnabled)

def bailBecauseA11yIsDisabled():
    if sys.argv[0].endswith("pydoc"): return
    try:
        if file("/proc/%s/cmdline" % os.getpid()).read().find('epydoc') != -1:
            return
    except: pass
    logger.log("Dogtail requires that Assistive Technology support be enabled. Aborting...")
    sys.exit(1)

def enableA11y(enable=True):
    """
    Enables accessibility via DConf.
    """
    from gi.repository.Gio import Settings
    InterfaceSettings = Settings(a11yDConfKey)
    dconfEnabled = InterfaceSettings.set_boolean('toolkit-accessibility', enable)

def checkForA11y():
    """
    Checks if accessibility is enabled, and halts execution if it is not.
    """
    if not isA11yEnabled(): bailBecauseA11yIsDisabled()

def checkForA11yInteractively():
    """
    Checks if accessibility is enabled, and presents a dialog prompting the
    user if it should be enabled if it is not already, then halts execution.
    """
    if isA11yEnabled(): return
    from gi.repository import Gtk
    dialog = Gtk.Dialog('Enable Assistive Technology Support?',
                     None,
                     Gtk.DialogFlags.MODAL | Gtk.DialogFlags.DESTROY_WITH_PARENT,
                     (Gtk.STOCK_QUIT, Gtk.ResponseType.CLOSE,
                         "_Enable", Gtk.ResponseType.ACCEPT))
    question = """Dogtail requires that Assistive Technology Support be enabled for it to function. Would you like to enable Assistive Technology support now?

Note that you will have to log out for the change to fully take effect.
    """.strip()
    dialog.set_default_response(Gtk.ResponseType.ACCEPT)
    questionLabel = Gtk.Label(label=question)
    questionLabel.set_line_wrap(True)
    dialog.vbox.pack_start(questionLabel, True, True, 0)
    dialog.show_all()
    result = dialog.run()
    if result == Gtk.ResponseType.ACCEPT:
        logger.log("Enabling accessibility...")
        enableA11y()
    elif result == Gtk.ResponseType.CLOSE:
       bailBecauseA11yIsDisabled()
    dialog.destroy()