Solve #133 Add hotkey component

druid/extended/hotkey.lua

@@ -0,0 +1,148 @@
+-- Copyright (c) 2021 Maksim Tuprikov <insality@gmail.com>. This code is licensed under MIT license
+
+--- Druid hotkey component
+-- @module Hotkey
+-- @within BaseComponent
+-- @alias druid.hotkey
+
+--- On change state callback(self, state)
+-- @tfield DruidEvent on_change_state @{DruidEvent}
+
+--- Visual node
+-- @tfield node node
+
+--- Button trigger node
+-- @tfield[opt=node] node click_node
+
+--- Button component from click_node
+-- @tfield Button button @{Button}
+
+---
+
+local helper = require("druid.helper")
+local component = require("druid.component")
+
+local Hotkey = component.create("hotkey")
+
+
+--- Component init function
+-- @tparam Hotkey self @{Hotkey}
+-- @tparam string[]|string keys The keys to be pressed for trigger callback. Should contains one key and any modificator keys
+-- @tparam function callback The callback function
+function Hotkey.init(self, keys, callback, callback_argument)
+	self.druid = self:get_druid()
+
+	self._hotkeys = {}
+	self._modificators = {}
+	self._callback = callback
+
+	if keys then
+		self:add_hotkey(keys, callback_argument)
+	end
+end
+
+
+--- Component style params.
+-- You can override this component styles params in druid styles table
+-- or create your own style
+-- @table style
+-- @tfield string[] MODIFICATORS The list of action_id as hotkey modificators
+function Hotkey.on_style_change(self, style)
+	self.style = {}
+	self.style.MODIFICATORS = style.MODIFICATORS or {}
+
+	for index = 1, #style.MODIFICATORS do
+		self.style.MODIFICATORS[index] = hash(self.style.MODIFICATORS[index])
+	end
+end
+
+
+--- Add hotkey for component callback
+-- @tparam Hotkey self @{Hotkey}
+-- @tparam string[]|hash[]|string|hash  Keys that have to be pressed before key pressed to activate
+function Hotkey.add_hotkey(self, keys, callback_argument)
+	keys = keys or {}
+	if type(keys) == "string" then
+		keys = { keys }
+	end
+
+	local modificators = {}
+	local key = nil
+
+	for index = 1, #keys do
+		local key_hash = hash(keys[index])
+		if helper.contains(self.style.MODIFICATORS, key_hash) then
+			table.insert(modificators, key_hash)
+		else
+			if not key then
+				key = key_hash
+			else
+				error("The hotkey keys should contains only one key (except modificator keys)")
+			end
+		end
+	end
+
+	table.insert(self._hotkeys, {
+		modificators = modificators,
+		key = key,
+		is_processing = false,
+		callback_argument = callback_argument,
+	})
+
+	-- Current hotkey status
+	for index = 1, #self.style.MODIFICATORS do
+		local modificator = hash(self.style.MODIFICATORS[index])
+		self._modificators[modificator] = self._modificators[modificator] or false
+	end
+
+	return self
+end
+
+
+function Hotkey.on_input(self, action_id, action)
+	if not action_id then
+		return
+	end
+
+	if self._modificators[action_id] ~= nil then
+		if action.pressed then
+			self._modificators[action_id] = true
+		end
+		if action.released then
+			self._modificators[action_id] = false
+		end
+	end
+
+	for index = 1, #self._hotkeys do
+		local hotkey = self._hotkeys[index]
+		if action_id == hotkey.key then
+			local is_modificator_ok = true
+
+			-- Check only required modificators pressed
+			for i = 1, #self.style.MODIFICATORS do
+				local mod = self.style.MODIFICATORS[i]
+				if helper.contains(hotkey.modificators, mod) and self._modificators[mod] == false then
+					is_modificator_ok = false
+				end
+				if not helper.contains(hotkey.modificators, mod) and self._modificators[mod] == true then
+					is_modificator_ok = false
+				end
+			end
+
+			if action.pressed and is_modificator_ok then
+				hotkey.is_processing = true
+			end
+			if action.released and is_modificator_ok and hotkey.is_processing then
+				hotkey.is_processing = false
+				if hotkey.callback_argument then
+					self._callback(self:get_context(), hotkey.callback_argument)
+				else
+					self._callback(self:get_context())
+				end
+			end
+		end
+	end
+end
+
+
+return Hotkey