"""
Easy menu selection tree
Contrib - Tim Ashley Jenkins 2017
This module allows you to create and initialize an entire branching EvMenu
instance with nothing but a multi-line string passed to one function.
EvMenu is incredibly powerful and flexible, but using it for simple menus
can often be fairly cumbersome - a simple menu that can branch into five
categories would require six nodes, each with options represented as a list
of dictionaries.
This module provides a function, init_tree_selection, which acts as a frontend
for EvMenu, dynamically sourcing the options from a multi-line string you provide.
For example, if you define a string as such:
TEST_MENU = '''Foo
Bar
Baz
Qux'''
And then use TEST_MENU as the 'treestr' source when you call init_tree_selection
on a player:
init_tree_selection(TEST_MENU, caller, callback)
The player will be presented with an EvMenu, like so:
___________________________
Make your selection:
___________________________
Foo
Bar
Baz
Qux
Making a selection will pass the selection's key to the specified callback as a
string along with the caller, as well as the index of the selection (the line number
on the source string) along with the source string for the tree itself.
In addition to specifying selections on the menu, you can also specify categories.
Categories are indicated by putting options below it preceded with a '-' character.
If a selection is a category, then choosing it will bring up a new menu node, prompting
the player to select between those options, or to go back to the previous menu. In
addition, categories are marked by default with a '[+]' at the end of their key. Both
this marker and the option to go back can be disabled.
Categories can be nested in other categories as well - just go another '-' deeper. You
can do this as many times as you like. There's no hard limit to the number of
categories you can go down.
For example, let's add some more options to our menu, turning 'Bar' into a category.
TEST_MENU = '''Foo
Bar
-You've got to know
--When to hold em
--When to fold em
--When to walk away
Baz
Qux'''
Now when we call the menu, we can see that 'Bar' has become a category instead of a
selectable option.
_______________________________
Make your selection:
_______________________________
Foo
Bar [+]
Baz
Qux
Note the [+] next to 'Bar'. If we select 'Bar', it'll show us the option listed under it.
________________________________________________________________
Bar
________________________________________________________________
You've got to know [+]
<< Go Back: Return to the previous menu.
Just the one option, which is a category itself, and the option to go back, which will
take us back to the previous menu. Let's select 'You've got to know'.
________________________________________________________________
You've got to know
________________________________________________________________
When to hold em
When to fold em
When to walk away
<< Go Back: Return to the previous menu.
Now we see the three options listed under it, too. We can select one of them or use 'Go
Back' to return to the 'Bar' menu we were just at before. It's very simple to make a
branching tree of selections!
One last thing - you can set the descriptions for the various options simply by adding a
':' character followed by the description to the option's line. For example, let's add a
description to 'Baz' in our menu:
TEST_MENU = '''Foo
Bar
-You've got to know
--When to hold em
--When to fold em
--When to walk away
Baz: Look at this one: the best option.
Qux'''
Now we see that the Baz option has a description attached that's separate from its key:
_______________________________________________________________
Make your selection:
_______________________________________________________________
Foo
Bar [+]
Baz: Look at this one: the best option.
Qux
Once the player makes a selection - let's say, 'Foo' - the menu will terminate and call
your specified callback with the selection, like so:
callback(caller, TEST_MENU, 0, "Foo")
The index of the selection is given along with a string containing the selection's key.
That way, if you have two selections in the menu with the same key, you can still
differentiate between them.
And that's all there is to it! For simple branching-tree selections, using this system is
much easier than manually creating EvMenu nodes. It also makes generating menus with dynamic
options much easier - since the source of the menu tree is just a string, you could easily
generate that string procedurally before passing it to the init_tree_selection function.
For example, if a player casts a spell or does an attack without specifying a target, instead
of giving them an error, you could present them with a list of valid targets to select by
generating a multi-line string of targets and passing it to init_tree_selection, with the
callable performing the maneuver once a selection is made.
This selection system only works for simple branching trees - doing anything really complicated
like jumping between categories or prompting for arbitrary input would still require a full
EvMenu implementation. For simple selections, however, I'm sure you will find using this function
to be much easier!
Included in this module is a sample menu and function which will let a player change the color
of their name - feel free to mess with it to get a feel for how this system works by importing
this module in your game's default_cmdsets.py module and adding CmdNameColor to your default
character's command set.
"""
from evennia import Command
from evennia.utils import evmenu
from evennia.utils.logger import log_trace
[docs]def init_tree_selection(
treestr,
caller,
callback,
index=None,
mark_category=True,
go_back=True,
cmd_on_exit="look",
start_text="Make your selection:",
):
"""
Prompts a player to select an option from a menu tree given as a multi-line string.
Args:
treestr (str): Multi-lne string representing menu options
caller (obj): Player to initialize the menu for
callback (callable): Function to run when a selection is made. Must take 4 args:
caller (obj): Caller given above
treestr (str): Menu tree string given above
index (int): Index of final selection
selection (str): Key of final selection
Options:
index (int or None): Index to start the menu at, or None for top level
mark_category (bool): If True, marks categories with a [+] symbol in the menu
go_back (bool): If True, present an option to go back to previous categories
start_text (str): Text to display at the top level of the menu
cmd_on_exit(str): Command to enter when the menu exits - 'look' by default
Notes:
This function will initialize an instance of EvMenu with options generated
dynamically from the source string, and passes the menu user's selection to
a function of your choosing. The EvMenu is made of a single, repeating node,
which will call itself over and over at different levels of the menu tree as
categories are selected.
Once a non-category selection is made, the user's selection will be passed to
the given callable, both as a string and as an index number. The index is given
to ensure every selection has a unique identifier, so that selections with the
same key in different categories can be distinguished between.
The menus called by this function are not persistent and cannot perform
complicated tasks like prompt for arbitrary input or jump multiple category
levels at once - you'll have to use EvMenu itself if you want to take full
advantage of its features.
"""
# Pass kwargs to store data needed in the menu
kwargs = {
"index": index,
"mark_category": mark_category,
"go_back": go_back,
"treestr": treestr,
"callback": callback,
"start_text": start_text,
}
# Initialize menu of selections
evmenu.EvMenu(
caller,
"evennia.contrib.utils.tree_select",
startnode="menunode_treeselect",
startnode_input=None,
cmd_on_exit=cmd_on_exit,
**kwargs,
)
[docs]def dashcount(entry):
"""
Counts the number of dashes at the beginning of a string. This
is needed to determine the depth of options in categories.
Args:
entry (str): String to count the dashes at the start of
Returns:
dashes (int): Number of dashes at the start
"""
dashes = 0
for char in entry:
if char == "-":
dashes += 1
else:
return dashes
return dashes
[docs]def is_category(treestr, index):
"""
Determines whether an option in a tree string is a category by
whether or not there are additional options below it.
Args:
treestr (str): Multi-line string representing menu options
index (int): Which line of the string to test
Returns:
is_category (bool): Whether the option is a category
"""
opt_list = treestr.split("\n")
# Not a category if it's the last one in the list
if index == len(opt_list) - 1:
return False
# Not a category if next option is not one level deeper
return not bool(dashcount(opt_list[index + 1]) != dashcount(opt_list[index]) + 1)
[docs]def parse_opts(treestr, category_index=None):
"""
Parses a tree string and given index into a list of options. If
category_index is none, returns all the options at the top level of
the menu. If category_index corresponds to a category, returns a list
of options under that category. If category_index corresponds to
an option that is not a category, it's a selection and returns True.
Args:
treestr (str): Multi-line string representing menu options
category_index (int): Index of category or None for top level
Returns:
kept_opts (list or True): Either a list of options in the selected
category or True if a selection was made
"""
dash_depth = 0
opt_list = treestr.split("\n")
kept_opts = []
# If a category index is given
if category_index != None:
# If given index is not a category, it's a selection - return True.
if not is_category(treestr, category_index):
return True
# Otherwise, change the dash depth to match the new category.
dash_depth = dashcount(opt_list[category_index]) + 1
# Delete everything before the category index
opt_list = opt_list[category_index + 1 :]
# Keep every option (referenced by index) at the appropriate depth
cur_index = 0
for option in opt_list:
if dashcount(option) == dash_depth:
if category_index == None:
kept_opts.append((cur_index, option[dash_depth:]))
else:
kept_opts.append((cur_index + category_index + 1, option[dash_depth:]))
# Exits the loop if leaving a category
if dashcount(option) < dash_depth:
return kept_opts
cur_index += 1
return kept_opts
[docs]def index_to_selection(treestr, index, desc=False):
"""
Given a menu tree string and an index, returns the corresponding selection's
name as a string. If 'desc' is set to True, will return the selection's
description as a string instead.
Args:
treestr (str): Multi-line string representing menu options
index (int): Index to convert to selection key or description
Options:
desc (bool): If true, returns description instead of key
Returns:
selection (str): Selection key or description if 'desc' is set
"""
opt_list = treestr.split("\n")
# Fetch the given line
selection = opt_list[index]
# Strip out the dashes at the start
selection = selection[dashcount(selection) :]
# Separate out description, if any
if ":" in selection:
# Split string into key and description
selection = selection.split(":", 1)
selection[1] = selection[1].strip(" ")
else:
# If no description given, set description to None
selection = [selection, None]
if not desc:
return selection[0]
else:
return selection[1]
[docs]def go_up_one_category(treestr, index):
"""
Given a menu tree string and an index, returns the category that the given option
belongs to. Used for the 'go back' option.
Args:
treestr (str): Multi-line string representing menu options
index (int): Index to determine the parent category of
Returns:
parent_category (int): Index of parent category
"""
opt_list = treestr.split("\n")
# Get the number of dashes deep the given index is
dash_level = dashcount(opt_list[index])
# Delete everything after the current index
opt_list = opt_list[: index + 1]
# If there's no dash, return 'None' to return to base menu
if dash_level == 0:
return None
current_index = index
# Go up through each option until we find one that's one category above
for selection in reversed(opt_list):
if dashcount(selection) == dash_level - 1:
return current_index
current_index -= 1
# The rest of this module is for the example menu and command! It'll change the color of your name.
"""
Here's an example string that you can initialize a menu from. Note the dashes at
the beginning of each line - that's how menu option depth and hierarchy is determined.
"""
NAMECOLOR_MENU = """Set name color: Choose a color for your name!
-Red shades: Various shades of |511red|n
--Red: |511Set your name to Red|n
--Pink: |533Set your name to Pink|n
--Maroon: |301Set your name to Maroon|n
-Orange shades: Various shades of |531orange|n
--Orange: |531Set your name to Orange|n
--Brown: |321Set your name to Brown|n
--Sienna: |420Set your name to Sienna|n
-Yellow shades: Various shades of |551yellow|n
--Yellow: |551Set your name to Yellow|n
--Gold: |540Set your name to Gold|n
--Dandelion: |553Set your name to Dandelion|n
-Green shades: Various shades of |141green|n
--Green: |141Set your name to Green|n
--Lime: |350Set your name to Lime|n
--Forest: |032Set your name to Forest|n
-Blue shades: Various shades of |115blue|n
--Blue: |115Set your name to Blue|n
--Cyan: |155Set your name to Cyan|n
--Navy: |113Set your name to Navy|n
-Purple shades: Various shades of |415purple|n
--Purple: |415Set your name to Purple|n
--Lavender: |535Set your name to Lavender|n
--Fuchsia: |503Set your name to Fuchsia|n
Remove name color: Remove your name color, if any"""
[docs]class CmdNameColor(Command):
"""
Set or remove a special color on your name. Just an example for the
easy menu selection tree contrib.
"""
key = "namecolor"
[docs] def func(self):
# This is all you have to do to initialize a menu!
init_tree_selection(
NAMECOLOR_MENU, self.caller, change_name_color, start_text="Name color options:"
)
[docs]def change_name_color(caller, treestr, index, selection):
"""
Changes a player's name color.
Args:
caller (obj): Character whose name to color.
treestr (str): String for the color change menu - unused
index (int): Index of menu selection - unused
selection (str): Selection made from the name color menu - used
to determine the color the player chose.
"""
# Store the caller's uncolored name
if not caller.db.uncolored_name:
caller.db.uncolored_name = caller.key
# Dictionary matching color selection names to color codes
colordict = {
"Red": "|511",
"Pink": "|533",
"Maroon": "|301",
"Orange": "|531",
"Brown": "|321",
"Sienna": "|420",
"Yellow": "|551",
"Gold": "|540",
"Dandelion": "|553",
"Green": "|141",
"Lime": "|350",
"Forest": "|032",
"Blue": "|115",
"Cyan": "|155",
"Navy": "|113",
"Purple": "|415",
"Lavender": "|535",
"Fuchsia": "|503",
}
# I know this probably isn't the best way to do this. It's just an example!
if selection == "Remove name color": # Player chose to remove their name color
caller.key = caller.db.uncolored_name
caller.msg("Name color removed.")
elif selection in colordict:
newcolor = colordict[selection] # Retrieve color code based on menu selection
caller.key = newcolor + caller.db.uncolored_name + "|n" # Add color code to caller's name
caller.msg(newcolor + ("Name color changed to %s!" % selection) + "|n")
