/ld27

-- Class: DebugStepper

-- This lets you pause execution of the app and step through it line by line.

-- This adds a function, debugger.breakpt(), that triggers this intrument.

-- Until this is called, the instrument remains hidden.

DebugStepper = DebugInstrument:extend

{

	visible = false,

	lineContext = 10,

	width = 'wide',

	_fileCache = {},

	onNew = function (self)

		self.stepIntoButton = self:add(DebugInstrumentButton:new

		{

			label = 'Step Into',

			onMouseUp = function (self)

				debugger._stepPaused = false

				debugger._stepFilter = nil

			end

		})

		self.stepOverButton = self:add(DebugInstrumentButton:new

		{

			label = 'Step Over',

			onMouseUp = function (self)

				debugger._stepPaused = false

				local prevStack = debugger._stepStack()

				debugger._stepFilter = function (stack)

					for i = 1, #stack - #prevStack do

						local match = true

						for j = 1, #prevStack do

							if stack[i + j] ~= prevStack[j] then

								match = false

								break

							end

						end

						-- we are now executing a sub-call;

						-- temporarily disable our line hook until

						-- we return to the previous function

						if match then

							debug.sethook(function()

								local state = debug.getinfo(3, 'f')

								if state.func == prevStack[1] then 

									-- we're at least on our old function, but is

									-- the stack depth the same?

									local depth = 1

									while true do

										state = debug.getinfo(3 + depth, 'f')

										if not state then break end

										depth = depth + 1

									end

									if depth == #prevStack then

										debug.sethook(debugger._stepLine, 'l')

									end

								end

							end, 'r')

							return false

						end

					end

					return true

				end

			end

		})

		self.stepOutButton = self:add(DebugInstrumentButton:new

		{

			label = 'Step Out',

			onMouseUp = function (self)

				debugger._stepPaused = false

				local prevStack = debugger._stepStack()

				-- disable our line hook until the current function returns

				debug.sethook(function()

					local depth = 2

					local match = false

					while true do

						local state = debug.getinfo(depth, 'f')

						if not state then

							match = true

							break

						elseif state.func ~= prevStack[depth - 1] then

							break

						end

						depth = depth + 1

					end

					if match then

						debug.sethook(debugger._stepLine, 'l')

					end

				end, 'r')

			end

		})

		self.continueButton = self:add(DebugInstrumentButton:new

		{

			label = 'Continue',

			onMouseUp = function (self)

				debugger._stepPaused = false

				debugger.endBreakpt()

			end

		})

		self.lineHighlight = self:add(Fill:new{ fill = {64, 64, 64}, height = 0, width = 0 })

		self.sourceLines = self:add(Text:new

		{

			font = self.font,

			width = 20,

			align = 'right',

			wordWrap = false,

		})

		self.sourceView = self:add(Text:new{ font = self.font, wordWrap = false })

		self.lineHeight = self.sourceView._fontObj:getHeight()

		self.title.text = 'Source'

		self.contentHeight = self.lineHeight * (self.lineContext + 1) * 2 + self.spacing * 3 +

		                     DebugInstrumentButton.height

		debugger.breakpt = function()

			local print = debugger.unsourcedPrint or print

			local caller = debug.getinfo(2, 'S')

			debugger.showConsole()

			self.visible = true

			print('\n' .. string.rep('=', 40))

			print('Breakpoint, ' .. caller.short_src .. ', ' .. caller.linedefined)

			print(string.rep('=', 40))

			debug.sethook(debugger._stepLine, 'l')

		end

		debugger.endBreakpt = function()

			self.visible = false

			if debugger.hideStack then debugger.hideStack() end

			if debugger.hideLocals then debugger.hideLocals() end

			debugger.hideConsole()

			debug.sethook()

		end

		-- hook to handle stepping over source

		debugger._stepLine = function (_, line)

			local state = debug.getinfo(2, 'Sl')

			if string.find(state.source, 'zoetrope/debug') or

			   (debugger._stepFilter and not debugger._stepFilter(debugger._stepStack())) then

				--print('skipping', state.source, state.currentline, #debugger._stepStack())

				return

			end

			if debugger.showStack then debugger.showStack(4) end

			if debugger.showLocals then debugger.showLocals(4) end

			local file = string.match(state.source, '^@(.*)')

			self:showLine(file, line)

			debugger._stepPaused = true

			local quit = false

			while debugger._stepPaused and not quit do

				quit = debugger._miniEventLoop()

			end

			if quit then

				debug.sethook()

				love.event.quit()

			end

		end

		-- returns a table representing the call stack during a source step

		debugger._stepStack = function()

			local level = 2

			local result = {}

			local info = {}

			local afterHook = false

			while true do

				info = debug.getinfo(level, 'f')

				if not info then break end

				if afterHook then

					table.insert(result, info.func)

				elseif info.func == debugger._stepLine then

					afterHook = true

				end

				level = level + 1

			end

			return result

		end

	end,

	onResize = function (self, x, y, width, height)

		self.sourceLines.x = x + self.spacing

		self.sourceLines.y = y + self.spacing

		self.sourceLines.height = height - self.sourceLines.y - self.spacing

		self.sourceView.x = self.sourceLines.x + self.sourceLines.width + self.spacing

		self.sourceView.y = self.sourceLines.y

		self.sourceView.width = width - self.sourceView.x - self.spacing * 2

		self.sourceView.height = self.sourceLines.height

		self.lineHighlight.x = x + self.spacing

		self.lineHighlight.y = self.sourceLines.y + self.lineHeight * self.lineContext

		self.lineHighlight.width = width - self.spacing * 2

		self.lineHighlight.height = self.lineHeight

		self.stepIntoButton.x = self.sourceLines.x

		self.stepIntoButton.y = self.sourceView.y + self.sourceView.height + self.spacing

		self.stepOverButton.x = self.stepIntoButton.x + self.stepIntoButton.width + self.spacing

		self.stepOverButton.y = self.stepIntoButton.y

		self.stepOutButton.x = self.stepOverButton.x + self.stepOverButton.width + self.spacing

		self.stepOutButton.y = self.stepOverButton.y

		self.continueButton.x = width - self.stepOverButton.width

		self.continueButton.y = self.stepOverButton.y

	end,

	showLine = function (self, file, line)

		if file then

			self.sourceLines.text = ''

			self.sourceView.text = ''

			for i = line - self.lineContext, line + self.lineContext + 1 do

				local source = debugger.sourceLine(file, i)

				if source then

					self.sourceLines.text = self.sourceLines.text .. i .. '\n'

					self.sourceView.text = self.sourceView.text .. string.gsub(debugger.sourceLine(file, i), '\t', string.rep(' ', 4)) .. '\n'

				end

			end

			self.title.text = file .. ':' .. line

		else

			self.title.text = 'Source'

			self.sourceView.text = '(source not available)'

		end

	end

}