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# Functions set for handling and rendering the data.
# Others developers can override these methods to tweak At.js such as matcher.
# We can override them in `callbacks` settings.
#
# @mixin
#
# The context of these functions is `$.atwho.Controller` object and they are called in this sequences:
#
# [beforeSave, matcher, filter, remoteFilter, afterMatchFailed, sorter, tplEval, highlighter, beforeReposition, beforeInsert, ]
#
DEFAULT_CALLBACKS =

# It would be called to restructure the data before At.js invokes `Model#save` to save data
# In default, At.js will convert it to a Hash Array.
#
# @param data [Array] data to refacotor.
# @return [Array] Data after refactor.
beforeSave: (data) ->

# It would be called to match the `flag`.
# It will match at start of line or after whitespace
#
# @param flag [String] current `flag` ("@", etc)
# @param subtext [String] Text from start to current caret position.
#
# @return [String | null] Matched result.
matcher: (flag, subtext, should_startWithSpace, acceptSpaceBar) ->

# ---------------------

# Filter data by matched string.
#
# @param query [String] Matched string.
# @param data [Array] data list
# @param searchKey [String] at char for searching.
#
# @return [Array] result data.
filter: (query, data, searchKey) ->

# If a function is given, At.js will invoke it if local filter can not find any data
#
# @param params [String] matched query
# @param callback [Function] callback to render page.
remoteFilter: null
# remoteFilter: (query, callback) ->
#   $.ajax url,
#     data: params
#     success: (data) ->
#       callback(data)

# Sorter data of course.
#
# @param query [String] matched string
# @param items [Array] data that was refactored
# @param searchKey [String] at char to search
#
# @return [Array] sorted data
sorter: (query, items, searchKey) ->

# Eval template for every single item in display list.
#
# @param tpl [String] The template string.
# @param map [Hash] Data map to eval.
#
# @return [String] the composed display data
tplEval: (tpl, map) ->

# Highlight the `matched query` string.
#
# @param li [String] HTML String after eval.
# @param query [String] matched query.
#
# @return [String] highlighted string.
highlighter: (li, query) ->

# What to do before inserting item's value into inputor.
#
# @param value [String] content to insert
# @param $li [jQuery Object] the chosen item
#
# @return [String] altered content to insert.
beforeInsert: (value, $li) ->

# You can adjust the menu's offset here.
#
# @param offset [Hash] offset will be applied to menu
# beforeReposition: (offset) ->
#   offset.left += 10
#   offset.top += 10
#   offset
beforeReposition: (offset) ->

# After the `matcher` was failed, which it can't get any query string.
afterMatchFailed: (at, el) ->