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--[[
	
			--*--*--*--*--*--*--*--*--*--*--*--*--*--*--	
			--*	             Shop Program            *--
			--*	    https://pastebin.com/XXXXXXXX    *--
			--*           by: GravityCube            *--
			--*--*--*--*--*--*--*--*--*--*--*--*--*--*--

			
	Changelog:
		1.0.0 First release. (DynamicChestShop fork https://pastebin.com/hQihjQ3b).
		1.1.0 Added colors for the categories.
		1.2.0 Changed currency to CLKeys
			1.2.1 Issue fixed with non-stackeable items.
			1.2.2 Bigger buy and qty buttons and change of color for buttons.
			1.2.3 Remove function fixed.
--]]
os.pullEvent = os.pullEventRaw
--------------------------------------
-->              APIs              <--
--------------------------------------
os.loadAPI("gcapi")
os.loadAPI("configAPI")
os.loadAPI("tableAPI")
os.loadAPI("windowAPI")
--------------------------------------
-->             Config             <--
--------------------------------------
local config = configAPI.open("config.cfg")

local mon = config:checkPeripheral("monitor", "Please enter the monitor name (enter 'search' for automatic detection): ", "monitor")
local me = config:checkPeripheral("me_system", "Please enter the me cable name (enter 'search' for automatic detection): ", "appeng_me_tilecolorlesscable")
local noteblock = config:checkPeripheral("noteblock", "Please enter noteblock name (enter 'search' for automatic detection): ", "music")
local pim = config:checkPeripheral("pim", "Please enter pim name (enter 'search' for automatic detection): ", "pim")
--------------------------------------
-->             CL KEYS            <--
--------------------------------------
os.loadAPI("keySystem")
keySystem.setup(pim, me)
--------------------------------------
-->          Listed Items          <--
--------------------------------------
local items_file = configAPI.open("items.list")

function checkMaxSizeItems()
	local items = items_file:get("items")
	for i, item in pairs(items) do
		if not item.max_size then
			local me_item = getItemFromME(item)
			if me_item then
				items[i].max_size = me_item.maxSize
			else
				print("Item " .. item.id .. ":" .. (item.dmg or 0) .. " not found in the me_system!")
				sleep(2)
			end
		end
	end
	items_file:put("items", items)
end

function getItemFromME(item)
	local inventory = me.getAvailableItems()
	for k,v in pairs(inventory) do
		if v.id == tonumber(item.id) and v.dmg == (tonumber(item.dmg) or 0) then
			return inventory[k]
		end
	end
	return nil
end

checkMaxSizeItems()
--------------------------------------
-->         Table Instance         <--
--------------------------------------
local category_colors = {}
local tableInstance = tableAPI.new(mon, (items_file:get("items") or {}), {"name", "qty", "price", "category"})
tableInstance.custom_colors_func.category = function(mon, txt)
		local color = category_colors[txt]
		if not color then
			local i = 0
			for k,v in pairs(category_colors) do i = i + 1 end
			color = 2^(i + 1)
			category_colors[txt] = color
			mon.setTextColor(color)
		else
			mon.setTextColor(color)
		end
	end
	
table.sort(tableInstance.data, function(a,b)
	if a.category == b.category then
		return a.name < b.name
	end
	return a.category < b.category
end)
tableInstance:draw()


--------------------------------------
-->         Sound Monitor          <--
--------------------------------------
tableInstance.playSound = function(self)
	noteblock.playSound("random.wood_click",1,1)
end
--------------------------------------
-->          Item delivery         <--
--------------------------------------
function getStock(item)
	local id = tonumber(item.id)
	local dmg = tonumber(item.dmg) or 0
	local stock = me.countOfItemType(id, dmg)
	return stock or 0
end

function sendItems(item)
	local queue_qty = item.qty
	for r=1, math.floor(queue_qty/(item.max_size or 64))+1 do
		local move_qty = item.max_size or 64
		if queue_qty < move_qty then move_qty = queue_qty end
		queue_qty = queue_qty - me.extractItem({["id"] = tonumber(item.id), ["dmg"] = tonumber(item.dmg), ["qty"] = move_qty}, "up")
	end
	if delivered_qty == item.qty then
		return true
	end
	return false, delivered_qty
end
--------------------------------------
-->       Transaction Window       <--
--------------------------------------
--[[
		--------------Close-
		- Name: item_name  -
		- ID: id           -
		- Qty: << < 1 > >> -
		- Price: $xxx      -
		- Category: xxx    -
		-                  -
		-Back-----------BUY-
	]]--
	
local TransactionWindow = {
	
	draw = function(self)
		self:clearButtonsMap()
		
		local mon = self.mon
		local max_x, max_y = mon.getSize()
		
		local item = self.item
		
		local width = ( ( 40 > ( 6 + string.len(item.name) ) ) and 40 ) or ( 6 + string.len(item.name) )
		
		local xi = gcapi.getCenter(max_x, width)
		local yi = gcapi.getCenter(max_y, 8)
		
		self.window = windowAPI.newWindow(mon, xi, yi, width, 8)
		local window = self.window
		
		window:setBackgroundColor(colors.white)
		window:clear()
		
		
		--** Borders
		window:setBackgroundColor(colors.cyan)
		for y=1, 8 do
			if y == 1 or y == 8 then
				window:setCursorPos(1,y)
				for x=1, width do
					window:write(" ")
				end
			end
		end
		
		for y=1, 8 do
			window:setCursorPos(width,y)
			window:write(" ")
		end
		
		for y=1, 8 do
			window:setCursorPos(1,y)
			window:write(" ")
		end
		
		--**Close button
		self:newButton(" X ", width-3,1,1,1, function() return true end)
		
		window:setBackgroundColor(colors.white)
		--**Item data
		window:setCursorPos(2,2)
		window:write("Name: " .. item.name)
		window:setCursorPos(2,3)
		window:write("ID: " .. item.id) if item.dmg then window:write(":" .. item.dmg) end
		window:setCursorPos(2,4)
		window:write("Qty: " .. item.qty .. " ") 
		
		--** << < Arrows > >>
		local cx, cy = window:getCursorPos()
		self:newButton(" < ", cx, cy, 3, 1, function() self:updateItemQty(-1) end)
		self:newButton(" > ", cx+4, cy, 3, 1, function() self:updateItemQty(1) end)
		
		window:setBackgroundColor(colors.white)
		window:setCursorPos(2,5)
		window:write("Price: " .. keySystem.priceToKeys(item.price) .. " keys" .. " (Virtual price: " .. math.floor(item.price*10)/1000 .. ")")
		window:setCursorPos(2,6)
		window:write("Category: " .. item.category)
		
		--** Back and Buy
		self:newButton("Back", 2,8,4,1, function() return true end)
		self:newButton(" Buy ", width-5,8,5,1, function()
				local stock = getStock(item)
				if stock < item.qty then
					self:displayMessage("There is no stock for this item", nil, colors.red)
					sleep(2)				
					self:draw()
					return false
				end
				
				local transaction_status, err = keySystem.withdraw(self.item.price, "Bought " .. item.id .. ":" .. (item.dmg or 0))
				if transaction_status then
					local text = "Thanks for your purchase!"
					self:displayMessage(text, nil, colors.lime)
					sendItems(item)
					sleep(2)			
					return true
				else
					self:displayMessage(err, nil, colors.red)
					sleep(2)			
					self:draw()
					return false
				end
			end)
		
	end,
	
	displayMessage = function(self, text, background_color, text_color)
		local background_color = background_color or colors.lightGray
		local text_color = text_color or colors.black
		local window = self.window
		local text = " " .. text .. " "
		
		window:setBackgroundColor(background_color)
		window:setTextColor(text_color)
		window:setCursorPos(gcapi.getCenter(window.width+1, text), gcapi.getCenter(window.heigth+1))
		window:write(text)
		window:setTextColor(colors.black)
	end,
	
	updateItemQty = function (self, diff)
		local item = self.item
		local org_qty = self.original_item["qty"]
		local new_qty = self.item["qty"] + org_qty*diff
		local stock = getStock(item)
		if new_qty > 0 and new_qty < 999 and stock >= new_qty then
			local pc = new_qty/self.item["qty"]
			item.price = item.price*pc
			item.qty = new_qty
		end
		self:draw()
	end,
	buttonListener = function (self)
		while true do
			local tEvent = {os.pullEvent()}
			if not self.window then
				return false
			end
			if tEvent[1] == "monitor_touch" then
				local x = tEvent[3]
				local y = tEvent[4]
				
				local ix = self.window.init_x + 1
				local iy = self.window.init_y + 1
				
				--if clic on the window
				if gcapi.numberBetween(x, ix, self.window.width+ix) and gcapi.numberBetween(y, iy, self.window.heigth+iy) then
					local buttonFunc = self.buttons_map[x][y] 
					if buttonFunc then
						if buttonFunc() then
							return true
						end
					end
				else
					return false
				end
			end
		end
	end,
	
	newButton = function(self, text, xi, yi, width, heigth, func)
		local drawButton = function(color)
			self.window:setBackgroundColor(color)
			local x_string = ""
			for x=xi, width+xi-1 do
				x_string = x_string .. " "
			end
			for y=yi, heigth+yi-1 do
				self.window:setCursorPos(xi, y)
				self.window:write(x_string)
			end
			self.window:setCursorPos(xi + gcapi.getCenter(width, text), yi + gcapi.getCenter(heigth))
			self.window:write(text)
		end
		drawButton(colors.cyan)
		for x=xi, width+xi-1 do
			for y=yi, heigth+yi-1 do
				self.buttons_map[x+self.window.init_x][y+self.window.init_y] = function()
					drawButton(colors.orange)
					sleep(0.15)
					drawButton(colors.cyan)
					if func then
						return func()
					end
				end
			end
		end
	end,
	
	clearButtonsMap = function(self)
		local max_x, max_y = self.mon.getSize()
		for x=1, max_x do
			self.buttons_map[x] = {}
		end
	end,
}

function createTransactionWindow(row_data)
	local max_x, max_y = mon.getSize()
	
	local transactionWindow = {
		item = gcapi.deepCopy(row_data),
		original_item = row_data,
		buttons_map = {}
	}
	transactionWindow.mon = mon
	for x=1, max_x do
		transactionWindow.buttons_map[x] = {}
	end
	setmetatable(transactionWindow, {__index = TransactionWindow})
	return transactionWindow
end


--------------------------------------
-->            Monitor             <--
--------------------------------------
function printTable(new_data)
	tableInstance.data = new_data
	tableInstance:draw()
end

function monitorListener()
	while true do
		local tEvent = {os.pullEvent()}
		local row_data, y = tableInstance:getRowOnEvent(tEvent)
		if row_data then
			tableInstance:highlight("name", row_data.name, true)
			tableInstance:draw()
			
			local transactionWindow = createTransactionWindow(row_data)
			transactionWindow:draw()
			transactionWindow:buttonListener()
			
			tableInstance:clearHighlights()
			tableInstance:draw()
		end
	end
end
--------------------------------------
-->            Terminal            <--
--------------------------------------
function commandListener()
	textutils.slowPrint(".......", 6)
	while true do
		
		verifyPassword("pass")
	
		term.clear()
		term.setCursorPos(1,1)
		term.write("Available commands: ")
		term.setCursorPos(1,2)
		term.write("1. add <name> <id> <amount> <price> <category>")
		term.setCursorPos(1,3)
		term.write("2. remove <id>")
		
		term.setCursorPos(1,5)
		term.write("Enter command: ")
		local input = read()
		
		tInput = gcapi.split(input .. " ", " ")
		
		
		if tInput[1] == "add" then
			local name = tInput[2]
			local id = tInput[3]
			local qty = tonumber(tInput[4])
			local price = tonumber(tInput[5])
			local category = tInput[6]
			
			if id and qty and price and category then
				local items = items_file:get("items") or {}
				local s = gcapi.split(id, ":")
				table.insert(items, {["id"] = s[1], ["dmg"] = s[2], ["name"] = name, ["price"] = price, ["qty"] = qty, ["category"] = category})
				printTable(items)
				items_file:put("items", items)
				print("Item " .. name .. " added!")
			else
				print("Wrong parameters!")
			end
		end
		
		if tInput[1] == "remove" then
			local id0 = tInput[2]
			if id0 then
				local s = gcapi.split(id0, ":")
				local id = s[1]
				local dmg = s[2]
				local items = items_file:get("items") or {}
				local new_items = {}
				local was_deleted = false
				for _,row_data in pairs(items) do
					if row_data.id ~= id or row_data.dmg ~= dmg then
						table.insert(new_items, row_data)
					else
						was_deleted = true
					end
				end
				if was_deleted then
					printTable(new_items)
					items_file:put("items", new_items)
					print("Item (ID: " .. id ..") deleted!")
				else
					print("Item (ID: " .. id ..") not found!")
				end
			end
		end
		
		if tInput[1] == "terminate" then
			return true
		end
		textutils.slowPrint("....", 4)
	end
end

function verifyPassword(pass)
	while true do
		term.clear()
		term.setCursorPos(1,1)
		term.write("Password: ")
		local input = read("*")
		if input == pass then
			return true
		else
			term.setCursorPos(1,2)
			term.write("Incorrect password!")
		end
	end
end

parallel.waitForAny(commandListener, monitorListener)