--[[
Author: TheOriginalBIT
Version: 2.0.4
Created: 03 Jan 2013
Last Update: 17 Feb 2013

License:

COPYRIGHT NOTICE
Copyright © 2013 Joshua Asbury a.k.a TheOriginalBIT [theoriginalbit@gmail.com]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
associated documentation files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
copies of the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

-The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
-Visible credit is given to the original author.
-The software is distributed in a non-profit way.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
]]--

--[[ PRIVATE CLASS VARIABLES AND FUNCTIONS ]]--

local version = 2.0
local apiIdentifier = string.format( "Loading Bar API v%.2f Object", version )
local sizeX, sizeY = term.getSize()
local isAdvanced = term.isColor and term.isColor()
local usedIds = {}

local function generateId()
	if #usedIds > 999 then error( "Maximum load bars reached, you have used 999, how?! Tell me on the forum post! Better yet, SHOW ME!" ) end
	local objId = #usedIds
	while usedIds[ objId ] do
		objId = objId + 1
		if objId > 999 then
			objId = 1
		end
	end
	usedIds[ objId ] = true
	return objId
end

local function modeToText( mode )
	if mode == STANDARD then
		return "STANDARD"
	elseif mode == BAR_ONLY then
		return "BAR_ONLY"
	elseif mode == ASCII_BAR_ONLY then
		return "ASCII_BAR_ONLY"
	elseif mode == LOGO_IS_LOAD then
		return "LOGO_IS_LOAD"
	elseif mode == LOGO_IS_OVERLAY then
		return "LOGO_IS_OVERLAY"
	elseif mode == ASCII then
		return "ASCII"
	else
		return "UNKNOWN"
	end
end

local function hexLookup( char )
	local value = tonumber(char, 16)
	return ( value and math.pow(2, value) or false )
end

local function clearScreen( color )
	term.setCursorPos(1,1)
	if isAdvanced then
		term.setBackgroundColor( color or colors.blue )
	end
	term.clear()
end

local function isValidMode( mode )
	return mode ~= nil and ( mode >= STANDARD and mode <= ASCII )
end

local function isValidParams( mode, tLogo, count, barWidth, y, loadCol, openingMsg, headMsg, footMsg )
	if mode == STANDARD then
		if type( tLogo ) ~= "table" then
			return false, "Logo must be table, got "..type( tLogo )
		elseif type( count ) ~= "number" then
			return false, "Event count must be a number, got "..type( count )
		elseif type( barWidth ) ~= "number" then
			return false, "Bar width must be a number, got "..type( barWidth )
		elseif type( y ) ~= "number" then
			return false, "Y position must be a number, got "..type( y )
		elseif type( loadCol ) ~= "number" then
			return false, "Load bar color must be a number, got "..type( loadCol )
		elseif type( loadCol ) == "number" and ( ( loadCol < 1 ) or ( loadCol > ( 2^16 ) - 1 ) ) then
			return false, "Invalid load bar color, must be in range 1-65535, got "..loadCol
		elseif type( openingMsg ) ~= "string" and type( openingMsg ) ~= "nil" then
			return false, "Invalid opening message, expected string or nil, got "..type( openingMsg )
		elseif type( headMsg ) ~= "string" and type( headMsg ) ~= "nil" then
			return false, "Invalid header message, expected string or nil, got "..type( headMsg )
		elseif type( footMsg ) ~= "string" and type( footMsg ) ~= "nil" then
			return false, "Invalid footer message, expected string or nil, got "..type( footMsg )
		end
		
		return true, nil
	elseif mode == BAR_ONLY then
		if type( tLogo ) ~= "nil" then
			return false, "Logo must be nil, got "..type( tLogo )
		elseif type( count ) ~= "number" then
			return false, "Event count must be a number, got "..type( count )
		elseif type( barWidth ) ~= "number" then
			return false, "Bar width must be a number, got "..type( barWidth )
		elseif type( y ) ~= "number" then
			return false, "Y position must be a number, got "..type( y )
		elseif type( loadCol ) ~= "number" then
			return false, "Load bar color must be a number, got "..type( loadCol )
		elseif type( loadCol ) == "number" and ( ( loadCol < 1 ) or ( loadCol > ( 2^16 ) - 1 ) ) then
			return false, "Invalid load bar color, must be in range 1-65535, got "..loadCol
		elseif type( openingMsg ) ~= "string" and type( openingMsg ) ~= "nil" then
			return false, "Invalid opening message, expected string or nil, got "..type( openingMsg )
		elseif type( headMsg ) ~= "string" and type( headMsg ) ~= "nil" then
			return false, "Invalid header message, expected string or nil, got "..type( headMsg )
		elseif type( footMsg ) ~= "string" and type( footMsg ) ~= "nil" then
			return false, "Invalid footer message, expected string or nil, got "..type( footMsg )
		end
		
		return true, nil
	elseif mode == ASCII_BAR_ONLY then
		if type( tLogo ) ~= "nil" then
			return false, "Logo must be nil, got "..type( tLogo )
		elseif type( count ) ~= "number" then
			return false, "Event count must be a number, got "..type( count )
		elseif type( barWidth ) ~= "number" then
			return false, "Bar width must be a number, got "..type( barWidth )
		elseif type( y ) ~= "number" then
			return false, "Y position must be a number, got "..type( y )
		elseif type( loadCol ) ~= "nil" then
			return false, "Load bar color must be nil, got "..type( loadCol )
		elseif type( loadCol ) == "number" and ( ( loadCol < 1 ) or ( loadCol > ( 2^16 ) - 1 ) ) then
			return false, "Invalid load bar color, must be in range 1-65535, got "..loadCol
		elseif type( openingMsg ) ~= "string" and type( openingMsg ) ~= "nil" then
			return false, "Invalid opening message, expected string or nil, got "..type( openingMsg )
		elseif type( headMsg ) ~= "string" and type( headMsg ) ~= "nil" then
			return false, "Invalid header message, expected string or nil, got "..type( headMsg )
		elseif type( footMsg ) ~= "string" and type( footMsg ) ~= "nil" then
			return false, "Invalid footer message, expected string or nil, got "..type( footMsg )
		end
		
		return true, nil
	elseif mode == LOGO_IS_LOAD or mode == LOGO_IS_OVERLAY then
		if type( tLogo ) ~= "table" then
			return false, "Logo must be table, got "..type( tLogo )
		elseif type( count ) ~= "number" then
			return false, "Event count must be a number, got "..type( count )
		elseif type( barWidth ) ~= "nil" then
			return false, "Bar width must be a nil, got "..type( barWidth )
		elseif type( y ) ~= "number" then
			return false, "Y position must be a number, got "..type( y )
		elseif mode == LOGO_IS_LOAD and type( loadCol ) ~= "number" then
			return false, "Load bar color must be a number, got "..type( loadCol )
		elseif mode == LOGO_IS_OVERLAY and type( loadCol ) ~= "nil" then
			return false, "Load bar color must be nil, got "..type( loadCol )
		elseif type( loadCol ) == "number" and ( ( loadCol < 1 ) or ( loadCol > ( 2^16 ) - 1 ) ) then
			return false, "Invalid load bar color, must be in range 1-65535, got "..loadCol
		elseif type( openingMsg ) ~= "string" and type( openingMsg ) ~= "nil" then
			return false, "Invalid opening message, expected string or nil, got "..type( openingMsg )
		elseif type( headMsg ) ~= "string" and type( headMsg ) ~= "nil" then
			return false, "Invalid header message, expected string or nil, got "..type( headMsg )
		elseif type( footMsg ) ~= "string" and type( footMsg ) ~= "nil" then
			return false, "Invalid footer message, expected string or nil, got "..type( footMsg )
		end
		
		return true, nil
	elseif mode == ASCII then
		if type( tLogo ) ~= "table" then
			return false, "Logo must be table, got "..type( tLogo )
		elseif type( count ) ~= "number" then
			return false, "Event count must be a number, got "..type( count )
		elseif type( barWidth ) ~= "number" then
			return false, "Bar width must be a number, got "..type( barWidth )
		elseif type( y ) ~= "number" then
			return false, "Y position must be a number, got "..type( y )
		elseif type( loadCol ) ~= "nil" then
			return false, "Load bar color must be a nil, got "..type( loadCol )
		elseif type( loadCol ) == "number" and ( ( loadCol < 1 ) or ( loadCol > ( 2^16 ) - 1 ) ) then
			return false, "Invalid load bar color, must be in range 1-65535, got "..loadCol
		elseif type( openingMsg ) ~= "string" and type( openingMsg ) ~= "nil" then
			return false, "Invalid opening message, expected string or nil, got "..type( openingMsg )
		elseif type( headMsg ) ~= "string" and type( headMsg ) ~= "nil" then
			return false, "Invalid header message, expected string or nil, got "..type( headMsg )
		elseif type( footMsg ) ~= "string" and type( footMsg ) ~= "nil" then
			return false, "Invalid footer message, expected string or nil, got "..type( footMsg )
		end
		
		return true, nil
	end
	
	return false, "Something went seriously wrong, please report this bug with the code 169:"..tostring( mode ).." and your call to this api."
end

local function getYFromMode( mode, logo, y )	
	if mode == STANDARD or mode == BAR_ONLY or mode == ASCII_BAR_ONLY or mode == ASCII then
		return ( y + 1 > sizeY and (y - 1) < 1) and sizeY - 4 or y
	elseif mode == LOGO_IS_LOAD or mode == LOGO_IS_OVERLAY then
		return math.ceil( sizeY / 2 - #logo / 2 )
	end
end

local function getWidthFromMode( mode, logo, width )
	if mode == STANDARD or mode == BAR_ONLY or mode == ASCII_BAR_ONLY or mode == ASCII then
		return width or 20
	elseif mode == LOGO_IS_LOAD or mode == LOGO_IS_OVERLAY then
		return logo[1] ~= nil and #logo[1] or 20
	end
end

local function draw_header_footer( data )
	if isAdvanced then
		term.setBackgroundColor( colors.white )
		term.setTextColor( colors.black )
	end
	term.setCursorPos( math.ceil( sizeX / 2 ) - math.ceil( string.len( data.headerMessage ) / 2 ), 1 )
	write( data.headerMessage )
	term.setCursorPos( math.ceil( sizeX / 2 ) - math.ceil( string.len( data.footerMessage ) / 2 ), sizeY )
	write( data.footerMessage )
end

local function draw_box( data )
	for x = 1, data.barWidth + 2 do
		for y = 1, 3 do
			term.setCursorPos( (sizeX - data.barWidth - 1) / 2 + x - 1, data.yPos + y -2 )
			local char = " "
			if x == 1 and y == 1 or x == data.barWidth + 2 and y == 1 then
				char = "."
			elseif x == 1 and y == 3 or x == data.barWidth + 2 and y == 3 then
				char = "'"
			elseif x == 1 or x == data.barWidth + 2 then
				char = "|"
			elseif y == 1 then
				char = "_"
			elseif y == 3 then
				char = "-"
			end
			
			write( char )
		end
	end
end

local function draw_progress_bar( self )
	if self.mode == ASCII_BAR_ONLY or self.mode == ASCII then
		draw_box( self.data )
	end
	
	for i = 1, self.data.barWidth do
		term.setCursorPos( (sizeX - self.data.barWidth) / 2 + i, self.data.yPos)
		local char = ' '
		if i < (( self.data.currentEventCount / self.data.totalEventCount ) * self.data.barWidth + 1) then
			if isAdvanced and self.data.barColor then
				term.setBackgroundColor( self.data.barColor )
			else
				char = '|'
			end
		else
			if isAdvanced and self.data.barColor then
				term.setBackgroundColor( colors.gray )
			end
		end
		
		write( char )
	end
end

local function draw_message( self )
	if self.data.progressMessage then
		term.setCursorPos( sizeX / 2 - self.data.progressMessage:len() / 2, sizeY - 3 )
		if isAdvanced then
			term.setTextColor( colors.black )
			term.setBackgroundColor( colors.white )
		end
		term.clearLine()
		term.write( self.data.progressMessage )
	end
end

local function drawScreen( self )
	if not ( self.mode == BAR_ONLY or self.mode == ASCII_BAR_ONLY ) then
		draw_header_footer( self.data )
	end
	
	for row = 1, #self.data.logo do
		for col = 1, self.data.logo[row]:len() do
			term.setCursorPos( math.ceil( sizeX / 2 - #self.data.logo[1] / 2 ) + col, self.data.isLogoLoad and self.data.yPos + row or (math.ceil( sizeY / 2 - #self.data.logo / 2 ) + row) - 2  )
			local char = self.data.logo[row]:sub( col, col )
			if char ~= " " then
				if not self.data.isLogoLoad or col > ( ( self.data.currentEventCount / self.data.totalEventCount ) * self.data.logo[1]:len() + ( self.data.currentEventCount == 0 and self.data.currentEventCount or 1 ) ) then
					if not ( self.mode == LOGO_IS_OVERLAY ) then
						term.setBackgroundColor( hexLookup( char ) )
					else
						term.setBackgroundColor( colors.lightGray )
					end
				else
					if not ( self.mode == LOGO_IS_OVERLAY ) then
						term.setBackgroundColor( self.data.barColor )
					else
						term.setBackgroundColor( hexLookup( char ) )
					end
				end
				write(" ")
			end
		end
		print()
	end
	
	if not self.data.isLogoLoad then
		draw_progress_bar( self )
	end
	
	if not ( self.mode == BAR_ONLY or self.mode == ASCII_BAR_ONLY ) then
		draw_message( self )
	end
end

local function drawScreenASCII( self )
	if not ( self.mode == BAR_ONLY or self.mode == ASCII_BAR_ONLY ) then
		draw_header_footer( self.data )
	end
	
	for row = 1, #self.data.logo do
		for col = 1, self.data.logo[row]:len() do
			term.setCursorPos( math.ceil( sizeX / 2 - #self.data.logo[1] / 2 ) + col, (math.ceil( sizeY / 2 - #self.data.logo / 2 ) + row) - 2  )
			local char = self.data.logo[row]:sub( col, col )
			if char ~= " " then
				if col > ( ( self.data.currentEventCount / self.data.totalEventCount ) * self.data.logo[1]:len() + ( self.data.currentEventCount == 0 and self.data.currentEventCount or 1 ) ) then
					write( char )
				end
			end
		end
		print()
	end
	
	draw_progress_bar( self )
	
	if not ( self.mode == BAR_ONLY or self.mode == ASCII_BAR_ONLY ) then
		draw_message( self )
	end
end

--[[ PUBLIC CLASS VARIABLES AND FUNCTIONS ]]--

function getVersion() return version end

function getApiIdentifier() return apiIdentifier end

--[[ OBJECT ]]--

load = {}

load.__index = load
load.__tostring = function( self ) return apiIdentifier end
load.__gc = function( self ) usedIds[ self.id ] = nil self.data.logo = nil self.data = nil self = nil end

--[[ GETTERS ]]--

function load.getId( self )
	return self.id
end

function load.getCurrentProgress( self )
	return self.data.currentEventCount
end

function load.getFormattedProgress( self )
	return self.data.currentEventCount.."/"..self.data.totalEventCount
end

--[[ SETTERS ]]--

function load.setMessage( self, msg )
	if not self.data then error( "Object does not exist", 2 ) end
	self.data.progressMessage = msg
	os.queueEvent( "load_update_"..self.id )
end

--[[ CONTRUCTORS / DESTRUCTORS ]]--

function init( lmode, tLogo, count, width, y, loadColor, openingMsg, headMsg, footMsg )
	if not isValidMode( lmode ) then error( "Bad argument: Invalid mode: "..type( lmode ).." : "..tostring( lmode ), 2 ) end
	if not isAdvanced and ( lmode ~= ASCII_BAR_ONLY and lmode ~= ASCII ) then error( "Invalid mode: Can only run in ASCII mode, attempted "..modeToText( lmode ), 2 ) end
	
	local valid, errorMsg = isValidParams( lmode, tLogo, count, width, y, loadColor, openingMsg, headMsg, footMsg )
	if not valid then error( "Bad argument: Invalid paramters for mode: "..modeToText( lmode ).." : "..errorMsg, 2 ) end
	
	local loadObject = { id = generateId(), data = {
		isLogoLoad = ( lmode == LOGO_IS_LOAD or lmode == LOGO_IS_OVERLAY ),
		isAscii = ( lmode == ASCII_BAR_ONLY or lmode == ASCII ),
		isBarOnly = ( lmode == BAR_ONLY or lmode == ASCII_BAR_ONLY ),
		logo = type( tLogo ) == "table" and tLogo or {},
		barWidth  = getWidthFromMode( lmode, tLogo, width ),
		yPos = getYFromMode( lmode, tLogo, y ),
		barColor = loadColor,
		totalEventCount = count,
		currentEventCount = 0,
		progressMessage = openingMsg or "",
		headerMessage = headMsg or "",
		footerMessage = footMsg or "",
	}, mode = lmode }
	
	setmetatable( loadObject, load )
	
	return loadObject
end

function load.dealloc( self )
	usedIds[ self.id ] = nil
	self.data.logo = nil
	self.data = nil
	self = nil
end

--[[ OBJECT FUNCTIONS ]]--

function load.reset( self )
	if not self.data then error( "Object does not exist", 2 ) end
	self.data.currentEventCount = 0
end

function load.forceStop( self )
	if not self.data then error( "Object does not exist", 2 ) end
	self.data.currentEventCount = self.data.totalEventCount
	os.queueEvent( "load_update_"..self.id )
end

function load.triggerUpdate( self, msg )
	if not self.data then error( "Object does not exist", 2 ) end
	self.data.currentEventCount = self.data.currentEventCount + 1
	if msg and msg:len() ~= 0 then self.data.progressMessage = msg end
	os.queueEvent( "load_update_"..self.id )
end

function load.removeMessage( self )
	if not self.data then error( "Object does not exist", 2 ) end
	self.data.progressMessage = ""
	os.queueEvent( "load_update_"..self.id )
end

function load.forceDraw( self )
	if not self.data then return end
	if not ( self.mode == BAR_ONLY or self.mode == ASCII_BAR_ONLY ) then error( "Object function can only be called in mode: BAR_ONLY and ASCII_BAR_ONLY", 2 ) end
	draw_progress_bar( self )
end

function load.run( self, cleanup )
	if not self.data then error( "Object is not initialized", 2 ) end
	
	if self.mode ~= BAR_ONLY and self.mode ~= ASCII_BAR_ONLY then
		clearScreen( colors.white )
	end
	
	if self.data.isAscii then
		drawScreenASCII( self )
	else
		drawScreen( self )
	end

	while true do
		if self.data.currentEventCount == self.data.totalEventCount then break end
		
		event = { os.pullEventRaw( "load_update_"..self.id ) }
		
		if self.mode == BAR_ONLY or self.mode == ASCII_BAR_ONLY then
			draw_progress_bar( self )
		elseif self.mode == ASCII then
			drawScreenASCII( self )
		else
			drawScreen( self )
		end
	end
	
	if cleanup == true then self:dealloc() end
end

STANDARD			= 1		-- Load screen with logo, text and bar 
BAR_ONLY			= 2		-- Progress bar only
ASCII_BAR_ONLY		= 3		-- Progress bar only - in ascii
LOGO_IS_LOAD		= 4		-- Load screen with logo and text - no bar, logo is progress indicator
LOGO_IS_OVERLAY		= 5		-- Load screen with logo and text - no bar, logo is progress indicator ( initially greyed out )
ASCII				= 6		-- Load screen with logo, text and bar - in ascii