# Tkinter font wrapper
#
# written by Fredrik Lundh, February 1998
#

__version__ = "0.9"

import itertools
import tkinter


# weight/slant
NORMAL = "normal"
ROMAN = "roman"
BOLD = "bold"
ITALIC = "italic"


def nametofont(name):
 """Given the name of a tk named font, returns a Font representation.
 """
 return Font(name=name, exists=True)


class Font:
 """Represents a named font.

 Constructor options are:

 font -- font specifier (name, system font, or (family, size, style)-tuple)
 name -- name to use for this font configuration (defaults to a unique name)
 exists -- does a named font by this name already exist?
 Creates a new named font if False, points to the existing font if True.
 Raises _tkinter.TclError if the assertion is false.

 the following are ignored if font is specified:

 family -- font 'family', e.g. Courier, Times, Helvetica
 size -- font size in points
 weight -- font thickness: NORMAL, BOLD
 slant -- font slant: ROMAN, ITALIC
 underline -- font underlining: false (0), true (1)
 overstrike -- font strikeout: false (0), true (1)

 """

 counter = itertools.count(1)

 def _set(self, kw):
 options = []
 for k, v in kw.items():
 options.append("-"+k)
 options.append(str(v))
 return tuple(options)

 def _get(self, args):
 options = []
 for k in args:
 options.append("-"+k)
 return tuple(options)

 def _mkdict(self, args):
 options = {}
 for i in range(0, len(args), 2):
 options[args[i][1:]] = args[i+1]
 return options

 def __init__(self, root=None, font=None, name=None, exists=False,
 **options):
 if not root:
 root = tkinter._default_root
 tk = getattr(root, 'tk', root)
 if font:
 # get actual settings corresponding to the given font
 font = tk.splitlist(tk.call("font", "actual", font))
 else:
 font = self._set(options)
 if not name:
 name = "font" + str(next(self.counter))
 self.name = name

 if exists:
 self.delete_font = False
 # confirm font exists
 if self.name not in tk.splitlist(tk.call("font", "names")):
 raise tkinter._tkinter.TclError(
 "named font %s does not already exist" % (self.name,))
 # if font config info supplied, apply it
 if font:
 tk.call("font", "configure", self.name, *font)
 else:
 # create new font (raises TclError if the font exists)
 tk.call("font", "create", self.name, *font)
 self.delete_font = True
 self._tk = tk
 self._split = tk.splitlist
 self._call = tk.call

 def __str__(self):
 return self.name

 def __eq__(self, other):
 return isinstance(other, Font) and self.name == other.name

 def __getitem__(self, key):
 return self.cget(key)

 def __setitem__(self, key, value):
 self.configure(**{key: value})

 def __del__(self):
 try:
 if self.delete_font:
 self._call("font", "delete", self.name)
 except Exception:
 pass

 def copy(self):
 "Return a distinct copy of the current font"
 return Font(self._tk, **self.actual())

 def actual(self, option=None, displayof=None):
 "Return actual font attributes"
 args = ()
 if displayof:
 args = ('-displayof', displayof)
 if option:
 args = args + ('-' + option, )
 return self._call("font", "actual", self.name, *args)
 else:
 return self._mkdict(
 self._split(self._call("font", "actual", self.name, *args)))

 def cget(self, option):
 "Get font attribute"
 return self._call("font", "config", self.name, "-"+option)

 def config(self, **options):
 "Modify font attributes"
 if options:
 self._call("font", "config", self.name,
 *self._set(options))
 else:
 return self._mkdict(
 self._split(self._call("font", "config", self.name)))

 configure = config

 def measure(self, text, displayof=None):
 "Return text width"
 args = (text,)
 if displayof:
 args = ('-displayof', displayof, text)
 return self._tk.getint(self._call("font", "measure", self.name, *args))

 def metrics(self, *options, **kw):
 """Return font metrics.

 For best performance, create a dummy widget
 using this font before calling this method."""
 args = ()
 displayof = kw.pop('displayof', None)
 if displayof:
 args = ('-displayof', displayof)
 if options:
 args = args + self._get(options)
 return self._tk.getint(
 self._call("font", "metrics", self.name, *args))
 else:
 res = self._split(self._call("font", "metrics", self.name, *args))
 options = {}
 for i in range(0, len(res), 2):
 options[res[i][1:]] = self._tk.getint(res[i+1])
 return options


def families(root=None, displayof=None):
 "Get font families (as a tuple)"
 if not root:
 root = tkinter._default_root
 args = ()
 if displayof:
 args = ('-displayof', displayof)
 return root.tk.splitlist(root.tk.call("font", "families", *args))


def names(root=None):
 "Get names of defined fonts (as a tuple)"
 if not root:
 root = tkinter._default_root
 return root.tk.splitlist(root.tk.call("font", "names"))


# --------------------------------------------------------------------
# test stuff

if __name__ == "__main__":

 root = tkinter.Tk()

 # create a font
 f = Font(family="times", size=30, weight=NORMAL)

 print(f.actual())
 print(f.actual("family"))
 print(f.actual("weight"))

 print(f.config())
 print(f.cget("family"))
 print(f.cget("weight"))

 print(names())

 print(f.measure("hello"), f.metrics("linespace"))

 print(f.metrics(displayof=root))

 f = Font(font=("Courier", 20, "bold"))
 print(f.measure("hello"), f.metrics("linespace", displayof=root))

 w = tkinter.Label(root, text="Hello, world", font=f)
 w.pack()

 w = tkinter.Button(root, text="Quit!", command=root.destroy)
 w.pack()

 fb = Font(font=w["font"]).copy()
 fb.config(weight=BOLD)

 w.config(font=fb)

 tkinter.mainloop()