/spacey

-- Class: DebugConsole

-- It can be used to keep track of fps, the position of a sprite,

-- and so on. It only updates when visible.

--

-- This also allows debugging hotkeys -- e.g. you could set it so that

-- pressing Control-Alt-I toggles invincibility of the player sprite.

-- Out of the box:

--		- Control-Alt-F toggles fullscreen

--		- Control-Alt-Q quits the app.

--		- Control-Alt-P deactivates the view.

-- 		- Control-Alt-R reloads all app code from on disk.

--		- Control-Alt-S saves a screenshot to the app's directory --

--		  see https://love2d.org/wiki/love.filesystem for where this is.

DebugConsole = Group:extend

{

	-- Property: toggleKey

	-- What key toggles visibility. By default, this is the tab key.

	toggleKey = 'tab',

	-- Property: hotkeyModifiers

	-- A table of modifier keys that must be held in order to activate

	-- a debugging hotkey (set via <addHotkey()>). If you want hotkeys to

	-- activate without having to hold any keys down, set this to nil.

	hotkeyModifiers = {'ctrl', 'alt'},

	-- Property: watchBasics

	-- If true, the console will automatically start watching the frames

	-- per second and memory usage. Changing this value after the object has

	-- been created has no effect.

	watchBasics = true,

	-- Property: watchWidth

	-- How wide the sidebar, where watch values are displayed, should be.

	watchWidth = 150,

	-- Property: inputHistory

	-- A table of previously-entered commands.

	inputHistory = {},

	-- Property: inputHistoryIndex

	-- Which history entry, if any, we are displaying.

	inputHistoryIndex = 1,

	-- Property: bg

	-- The background <Fill> used to darken the view.

	-- Property: log

	-- The <Text> sprite showing recent lines in the log.

	-- Property: watchList

	-- The <Text> sprite showing the state of all watched variables.

	-- Property: input

	-- The <TextInput> that the user types into to enter commands.

	-- Property: prompt

	-- The <Text> sprite that shows a > in front of commands.

	-- internal property: _bindings

	-- Keeps track of debugging hotkeys.

	new = function (self, obj)

		local width = the.app.width

		local height = the.app.height

		obj = self:extend(obj)

		obj.visible = false

		obj._watches = {}

		obj._hotkeys = {}

		obj.fill = Fill:new{ x = 0, y = 0, width = width, height = height, fill = {0, 0, 0, 200} }

		obj:add(obj.fill)

		obj.log = Text:new{ x = 4, y = 4, width = width - self.watchWidth - 8, height = height - 8, text = '' }

		obj:add(obj.log)

		obj.watchList = Text:new{ x = width - self.watchWidth - 4, y = 4,

								   width = self.watchWidth - 8, height = height - 8, text = '', wordWrap = false }

		obj:add(obj.watchList)

		obj.prompt = Text:new{ x = 4, y = 0, width = 100, text = '>' }

		obj:add(obj.prompt)

		local inputIndent = obj.log._fontObj:getWidth('>') + 4

		obj.input = TextInput:new

		{

			x = inputIndent, y = 0, width = the.app.width,

			active = false,

			onType = function (self, char)

				return char ~= the.console.toggleKey

			end

		}

		obj:add(obj.input)

		-- some default behavior

		obj:addHotkey('f', function() the.app:toggleFullscreen() end)

		obj:addHotkey('p', function()

			the.view.active = not the.view.active

			if the.view.active then

				the.view:tint()

			else

				the.view:tint(0, 0, 0, 200)

			end

		end)

		obj:addHotkey('q', love.event.quit)

		if debugger then obj:addHotkey('r', debugger.reload) end

		obj:addHotkey('s', function() the.app:saveScreenshot('screenshot.png') end)

		if obj.watchBasics then

			obj:watch('FPS', 'love.timer.getFPS()')

			obj:watch('Memory', 'math.floor(collectgarbage("count") / 1024) .. "M"')

		end

		-- hijack print function

		-- this is nasty to debug if it goes wrong, be careful

		obj._oldPrint = print

		print = function (...)

			local caller = debug.getinfo(2)

			if caller.linedefined ~= 0 then

				obj.log.text = obj.log.text .. '(' .. caller.short_src .. ':' .. caller.linedefined .. ') '

			end

			for _, value in pairs{...} do

				obj.log.text = obj.log.text .. tostring(value) .. ' '

			end

			obj.log.text = obj.log.text .. '\n'

			obj._updateLog = true

			obj._oldPrint(...)

		end

		debugger._unsourcedPrint = function (...)

			for _, value in pairs{...} do

				obj.log.text = obj.log.text .. tostring(value) .. ' '

			end

			obj.log.text = obj.log.text .. '\n'

			obj._updateLog = true

			obj._oldPrint(...)

		end

		the.console = obj

		if obj.onNew then obj.onNew() end

		return obj

	end,

	-- Method: watch

	-- Adds an expression to be watched.

	--

	-- Arguments:

	--		label - string label

	--		expression - expression to evaluate as a string

	watch = function (self, label, expression)

		table.insert(self._watches, { label = label,

									  func = loadstring('return ' .. expression) })

	end,

	-- Method: addHotkey

	-- Adds a hotkey to execute a function. This hotkey will require

	-- holding down whatever modifiers are set in <hotkeyModifiers>.

	--

	-- Arguments:

	--		key - key to trigger the hotkey

	--		func - function to run. This will receive the key that

	--			   was pressed, so you can re-use functions (i.e. 

	--			   the 1 key loads level 1, the 2 key loads level 2).

	--

	-- Returns:

	--		nothing

	addHotkey = function (self, key, func)

		table.insert(self._hotkeys, { key = key, func = func })

	end,

	-- Method: execute

	-- Safely executes a string of code and prints the result.

	--

	-- Arguments:

	--		code - string code to execute

	--

	-- Returns:

	--		string result

	execute = function (self, code)

		if string.sub(code, 1, 1) == '=' then

			code = 'debugger._unsourcedPrint (' .. string.sub(code, 2) .. ')'

		end

		local func, err = loadstring(code)

		if func then

			local ok, result = pcall(func)

			if not ok then

				debugger._unsourcedPrint('Error, ' .. tostring(result) .. '\n')

			else

				debugger._unsourcedPrint('')

			end

			return tostring(result)

		else

			debugger._unsourcedPrint('Syntax error, ' .. string.gsub(tostring(err), '^.*:', '') .. '\n')

		end

	end,

	-- Method: show

	-- Shows the debug console.

	-- 

	-- Arguments:

	--		none

	--

	-- Returns:

	--		nothing

	show = function (self)

		self.visible = true

		self.input.active = true

	end,

	-- Method: hide

	-- Hides the debug console.

	-- 

	-- Arguments:

	--		none

	--

	-- Returns:

	--		nothing

	hide = function (self)

		self.visible = false

		self.input.active = false

	end,

	update = function (self, elapsed)

		-- listen for visibility key

		if the.keys:justPressed(self.toggleKey) then

			self.visible = not self.visible

			self.input.active = self.visible

		end

		-- listen for hotkeys

		local modifiers = (self.hotkeyModifiers == nil)

		if not modifiers then

			modifiers = true

			for _, key in pairs(self.hotkeyModifiers) do

				if not the.keys:pressed(key) then

					modifiers = false

					break

				end

			end

		end

		if modifiers then

			for _, hotkey in pairs(self._hotkeys) do

				if the.keys:justPressed(hotkey.key) then

					hotkey.func(hotkey.key)

				end

			end

		end

		if self.visible then

			-- update watches

			self.watchList.text = ''

			for _, watch in pairs(self._watches) do

				local ok, value = pcall(watch.func)

				if not ok then value = nil end

				self.watchList.text = self.watchList.text .. watch.label .. ': ' .. tostring(value) .. '\n'

			end

			-- update log

			if self._updateLog then

				local lineHeight = self.log._fontObj:getHeight()

				local _, height = self.log:getSize()

				local linesToDelete = math.ceil((height - the.app.height - 20) / lineHeight)

				if linesToDelete > 0 then

					self.log.text = string.gsub(self.log.text, '.-\n', '', linesToDelete) 

					height = height - linesToDelete * lineHeight

				end

				self.prompt.y = height + 4

				self.input.y = height + 4

				self._updateLog = false

			end

			-- handle special keys at the console

			if the.keys:pressed('ctrl') and the.keys:justPressed('a') then

				self.input.caret = 0

			end

			if the.keys:pressed('ctrl') and the.keys:justPressed('e') then

				self.input.caret = string.len(self.input.text)

			end

			if the.keys:pressed('ctrl') and the.keys:justPressed('k') then

				self.input.caret = 0

				self.input.text = ''

			end

			if the.keys:justPressed('up') and self.inputHistoryIndex > 1 then

				-- save what the user was in the middle of typing

				self.inputHistory[self.inputHistoryIndex] = self.input.text

				self.input.text = self.inputHistory[self.inputHistoryIndex - 1]

				self.input.caret = string.len(self.input.text)

				self.inputHistoryIndex = self.inputHistoryIndex - 1

			end

			if the.keys:justPressed('down') and self.inputHistoryIndex < #self.inputHistory then

				self.input.text = self.inputHistory[self.inputHistoryIndex + 1]

				self.input.caret = string.len(self.input.text)

				self.inputHistoryIndex = self.inputHistoryIndex + 1

			end

			if the.keys:justPressed('return') then

				debugger._unsourcedPrint('>' .. self.input.text)

				self:execute(self.input.text)

				table.insert(self.inputHistory, self.inputHistoryIndex, self.input.text)

				while #self.inputHistory > self.inputHistoryIndex do

					table.remove(self.inputHistory)

				end

				self.inputHistoryIndex = self.inputHistoryIndex + 1

				self.input.text = ''

				self.input.caret = 0

			end

		end

		Group.update(self, elapsed)

	end

}

-- Function: debugger.reload

-- Resets the entire app and forces all code to be reloaded from 

-- on disk. via https://love2d.org/forums/viewtopic.php?f=3&t=7965

-- 

-- Arguments:

--		none

--

-- Returns:

--		nothing

if debugger then

	debugger.reload = function()

		if DEBUG then

			love.audio.stop()

			-- create local references to needed variables

			-- because we're about to blow the global scope away

			local initialGlobals = debugger._initialGlobals

			local initialPackages = debugger._initialPackages

			-- reset global scope

			for key, _ in pairs(_G) do

				_G[key] = initialGlobals[key]

			end

			-- reload main file and restart

			for key, _ in pairs(package.loaded) do

				if not initialPackages[key] then

					package.loaded[key] = nil

				end

			end

			require('main')

			love.load()

		end

	end

end