"""Applet that lets the user look in the cache.

NB This uses secret knowledge about Grail internals that may change or
become inaccessible to applets.

Still, it's a cool applet!

"""

from Tkinter import *
import tktools
import string

class CacheLook:

    def __init__(self, parent):
	self.parent=parent

	self.viewer = parent.grail_viewer
	self.browser = parent.grail_browser
	self.app = parent.grail_app

	self.keys = self.app.get_cache_keys()
	self.keys.sort()

	self.list, self.frame = tktools.make_list_box(
	    parent,
	    width=60, height=min(20, len(self.keys)+1),
	    hbar=1, vbar=1)
	self.list.config(exportselection=0)

	for key in self.keys:
	    self.list.insert(END, key)

	self.new_browser = None

	self.list.bind('<Double-Button-1>', self.open_item_event)

	self.control_frame = Frame(self.parent)
	self.control_frame.pack(expand=1, fill=BOTH)

	self.refresh_button = Button(self.control_frame,
				     text="Refresh List",
				     command=self.refresh_command)
	self.refresh_button.pack(side=RIGHT)

	self.view_button = Button(self.control_frame,
				  text="View",
				  command=self.view_command)
	self.view_button.pack(side=LEFT)

	self.view_source_button = Button(self.control_frame,
				  text="View Source",
				  command=self.view_source_command)
	self.view_source_button.pack(side=LEFT)

    def view_command(self):
	self.open_item()

    def view_source_command(self):
	self.open_item(show_source=1)

    def refresh_command(self):
	self.refresh()

    def open_item_event(self, event):
	self.open_item()

    def open_item(self, show_source=0):
	items = self.list.curselection()
	if not items:
	    self.list.bell()
	    return
	i = string.atoi(items[0])
	url = self.list.get(i)
	if not self.new_browser or not self.new_browser.valid():
	    self.new_browser = self.browser.new_command()
	self.new_browser.context.load(url, show_source=show_source)

    def check(self, event=None):
	keys = self.app.get_cache_keys()
	keys.sort()
	if keys != self.keys:
	    self.refresh(keys=keys)

    def refresh(self, event=None, keys=None):

	if keys:
	    self.keys = keys
	else:
	    self.keys = self.app.get_cache_keys()
	    self.keys.sort()

	self.list.delete(0, END)

	for key in self.keys:
	    self.list.insert(END, key)