"""A CallTip window class for Tkinter/IDLE.

After ToolTip.py, which uses ideas gleaned from PySol

Used by the CallTips IDLE extension.

"""

from Tkinter import *

HIDE_VIRTUAL_EVENT_NAME = "<<calltipwindow-hide>>"

HIDE_SEQUENCES = ("<Key-Escape>", "<FocusOut>")

CHECKHIDE_VIRTUAL_EVENT_NAME = "<<calltipwindow-checkhide>>"

CHECKHIDE_SEQUENCES = ("<KeyRelease>", "<ButtonRelease>")

CHECKHIDE_TIME = 100 # miliseconds

MARK_RIGHT = "calltipwindowregion_right"

class CallTip:

    def __init__(self, widget):

        self.widget = widget

        self.tipwindow = self.label = None

        self.parenline = self.parencol = None

        self.lastline = None

        self.hideid = self.checkhideid = None

    def position_window(self):

        """Check if needs to reposition the window, and if so - do it."""

        curline = int(self.widget.index("insert").split('.')[0])

        if curline == self.lastline:

            return

        self.lastline = curline

        self.widget.see("insert")

        if curline == self.parenline:

            box = self.widget.bbox("%d.%d" % (self.parenline,

                                              self.parencol))

        else:

            box = self.widget.bbox("%d.0" % curline)

        if not box:

            box = list(self.widget.bbox("insert"))

            # align to left of window

            box[0] = 0

            box[2] = 0

        x = box[0] + self.widget.winfo_rootx() + 2

        y = box[1] + box[3] + self.widget.winfo_rooty()

        self.tipwindow.wm_geometry("+%d+%d" % (x, y))

    def showtip(self, text, parenleft, parenright):

        """Show the calltip, bind events which will close it and reposition it.

        """

        # truncate overly long calltip

        if len(text) >= 79:

            textlines = text.splitlines()

            for i, line in enumerate(textlines):

                if len(line) > 79:

                    textlines[i] = line[:75] + ' ...'

            text = '\n'.join(textlines)

        self.text = text

        if self.tipwindow or not self.text:

            return

        self.widget.mark_set(MARK_RIGHT, parenright)

        self.parenline, self.parencol = map(

            int, self.widget.index(parenleft).split("."))

        self.tipwindow = tw = Toplevel(self.widget)

        self.position_window()

        # remove border on calltip window

        tw.wm_overrideredirect(1)

        try:

            # This command is only needed and available on Tk >= 8.4.0 for OSX

            # Without it, call tips intrude on the typing process by grabbing

            # the focus.

            tw.tk.call("::tk::unsupported::MacWindowStyle", "style", tw._w,

                       "help", "noActivates")

        except TclError:

            pass

        self.label = Label(tw, text=self.text, justify=LEFT,

                           background="#ffffe0", relief=SOLID, borderwidth=1,

                           font = self.widget['font'])

        self.label.pack()

        self.checkhideid = self.widget.bind(CHECKHIDE_VIRTUAL_EVENT_NAME,

                                            self.checkhide_event)

        for seq in CHECKHIDE_SEQUENCES:

            self.widget.event_add(CHECKHIDE_VIRTUAL_EVENT_NAME, seq)

        self.widget.after(CHECKHIDE_TIME, self.checkhide_event)

        self.hideid = self.widget.bind(HIDE_VIRTUAL_EVENT_NAME,

                                       self.hide_event)

        for seq in HIDE_SEQUENCES:

            self.widget.event_add(HIDE_VIRTUAL_EVENT_NAME, seq)

    def checkhide_event(self, event=None):

        if not self.tipwindow:

            # If the event was triggered by the same event that unbinded

            # this function, the function will be called nevertheless,

            # so do nothing in this case.

            return

        curline, curcol = map(int, self.widget.index("insert").split('.'))

        if curline < self.parenline or \

           (curline == self.parenline and curcol <= self.parencol) or \

           self.widget.compare("insert", ">", MARK_RIGHT):

            self.hidetip()

        else:

            self.position_window()

            self.widget.after(CHECKHIDE_TIME, self.checkhide_event)

    def hide_event(self, event):

        if not self.tipwindow:

            # See the explanation in checkhide_event.

            return

        self.hidetip()

    def hidetip(self):

        if not self.tipwindow:

            return

        for seq in CHECKHIDE_SEQUENCES:

            self.widget.event_delete(CHECKHIDE_VIRTUAL_EVENT_NAME, seq)

        self.widget.unbind(CHECKHIDE_VIRTUAL_EVENT_NAME, self.checkhideid)

        self.checkhideid = None

        for seq in HIDE_SEQUENCES:

            self.widget.event_delete(HIDE_VIRTUAL_EVENT_NAME, seq)

        self.widget.unbind(HIDE_VIRTUAL_EVENT_NAME, self.hideid)

        self.hideid = None

        self.label.destroy()

        self.label = None

        self.tipwindow.destroy()

        self.tipwindow = None

        self.widget.mark_unset(MARK_RIGHT)

        self.parenline = self.parencol = self.lastline = None

    def is_active(self):

        return bool(self.tipwindow)

###############################

#

# Test Code

#

class container: # Conceptually an editor_window

    def __init__(self):

        root = Tk()

        text = self.text = Text(root)

        text.pack(side=LEFT, fill=BOTH, expand=1)

        text.insert("insert", "string.split")

        root.update()

        self.calltip = CallTip(text)

        text.event_add("<<calltip-show>>", "(")

        text.event_add("<<calltip-hide>>", ")")

        text.bind("<<calltip-show>>", self.calltip_show)

        text.bind("<<calltip-hide>>", self.calltip_hide)

        text.focus_set()

        root.mainloop()

    def calltip_show(self, event):

        self.calltip.showtip("Hello world")

    def calltip_hide(self, event):

        self.calltip.hidetip()

def main():

    # Test code

    c=container()

if __name__=='__main__':

    main()