TradeServer

--VARIABLES
local rs = game.ReplicatedStorage:WaitForChild("TradeReplicatedStorage")
local re = rs:WaitForChild("RemoteEvent")
local config = require(rs:WaitForChild("CONFIGURATION"))

local tradeRequestsFolder = Instance.new("Folder")
tradeRequestsFolder.Name = "TRADE REQUESTS"
tradeRequestsFolder.Parent = rs

local ongoingTradesFolder = Instance.new("Folder")
ongoingTradesFolder.Name = "ONGOING TRADES"
ongoingTradesFolder.Parent = rs


--REMOVE TRADES FOR THIS PLAYER
function removeTrades(plr)
    for i, trade in pairs(ongoingTradesFolder:GetChildren()) do
        if trade.Sender.Value == plr.Name or trade.Receiver.Value == plr.Name then
            trade:Destroy()
        end
    end

    for i, request in pairs(tradeRequestsFolder:GetChildren()) do
        if request.Name == plr.Name or request.Value == plr.Name then
            request:Destroy()
        end
    end
end


--REMOVE TRADES WHEN PLAYER DIES
game.Players.PlayerAdded:Connect(function(plr)
    plr.CharacterAdded:Connect(function(char)

        char:WaitForChild("Humanoid").Died:Connect(function()
            removeTrades(plr)
        end)
    end)
end)

--REMOVE TRADES WHEN PLAYER LEAVES
game.Players.PlayerRemoving:Connect(removeTrades)


--RECEIVE CLIENT INFORMATION
re.OnServerEvent:Connect(function(plr, instruction, data)

    --Send a request
    if instruction == "send trade request" then

        local playerSent = data[1]

        if playerSent and playerSent ~= plr then
            local inTrade = false

            for i, trade in pairs(ongoingTradesFolder:GetChildren()) do
                if trade.Sender.Value == playerSent.Name or trade.Sender.Value == plr.Name or trade.Receiever.Value == playerSent.Name or trade.Receiver.Value == plr.Name then
                    inTrade = true
                    break
                end
            end

            for i, request in pairs(tradeRequestsFolder:GetChildren()) do
                if request.Name == playerSent.Name or request.Name == plr.Name or request.Value == playerSent.Name or request.Value == plr.Name then
                    inTrade = true
                    break
                end
            end

            if not inTrade then

                local newRequest = Instance.new("StringValue")
                newRequest.Name = plr.Name
                newRequest.Value = playerSent.Name
                newRequest.Parent = tradeRequestsFolder
            end
        end


    --Reject a request
    elseif instruction == "reject trade request" then

        local requestValue = nil
        for i, request in pairs(tradeRequestsFolder:GetChildren()) do
            if request.Name == plr.Name or request.Value == plr.Name then
                requestValue = request
                break
            end
        end

        if requestValue.Parent == tradeRequestsFolder and requestValue.Name == plr.Name or requestValue.Value == plr.Name then
            requestValue:Destroy()
        end


    --Accept a request
    elseif instruction == "accept trade request" then

        local requestValue = nil
        for i, request in pairs(tradeRequestsFolder:GetChildren()) do
            if request.Name == plr.Name or request.Value == plr.Name then
                requestValue = request
                break
            end
        end

        if requestValue.Parent == tradeRequestsFolder and requestValue.Value == plr.Name then

            local senderPlr = game.Players[requestValue.Name]
            local receiverPlr = game.Players[requestValue.Value]


            requestValue:Destroy()

            local tradeFolder = Instance.new("Folder")

            local senderValue = Instance.new("StringValue")
            senderValue.Name = "Sender"
            senderValue.Value = senderPlr.Name
            senderValue.Parent = tradeFolder

            local receiverValue = Instance.new("StringValue")
            receiverValue.Name = "Receiver"
            receiverValue.Value = receiverPlr.Name
            receiverValue.Parent = tradeFolder

            local senderOffer = Instance.new("Folder")
            senderOffer.Name = senderPlr.Name .. "'s offer"
            senderOffer.Parent = tradeFolder

            local receiverOffer = Instance.new("Folder")
            receiverOffer.Name = receiverPlr.Name .. "'s offer"
            receiverOffer.Parent = tradeFolder

            tradeFolder.Parent = ongoingTradesFolder


            local toolIds = {}

            local senderTools = config.GetTools(senderPlr)
            for i, tool in pairs(senderTools) do
                tool.CanBeDropped = false

                local toolId = tool:FindFirstChild("TRADING ID") or Instance.new("NumberValue")
                toolId.Name = "TRADING ID"

                while string.len(tostring(toolId.Value)) < 1 or table.find(toolIds, toolId.Value) do
                    toolId.Value = Random.new():NextNumber(0, 1000000)
                end
                table.insert(toolIds, toolId.Value)

                toolId.Parent = tool
            end

            local receiverTools = config.GetTools(receiverPlr)
            for i, tool in pairs(receiverTools) do
                tool.CanBeDropped = false

                local toolId = tool:FindFirstChild("TRADING ID") or Instance.new("NumberValue")
                toolId.Name = "TRADING ID"

                while string.len(tostring(toolId.Value)) < 1 or table.find(toolIds, toolId.Value) do
                    toolId.Value = Random.new():NextNumber(0, 1000000)
                end
                table.insert(toolIds, toolId.Value)

                toolId.Parent = tool
            end
        end


    --Add an item to the trade
    elseif instruction == "add item to trade" then

        local item = data[1]

        if item.Parent == plr.Backpack or item.Parent == plr.Character then

            local currentTrade = nil
            for i, trade in pairs(ongoingTradesFolder:GetChildren()) do
                if trade.Sender.Value == plr.Name or trade.Receiver.Value == plr.Name then
                    currentTrade = trade
                    break
                end
            end

            if currentTrade then

                local plrSlots = currentTrade[plr.Name .. "'s offer"]
                local numItems = #plrSlots:GetChildren()

                if numItems < config.MaxSlots then

                    local itemInTrade = false

                    for i, plrItem in pairs(plrSlots:GetChildren()) do
                        if plrItem["TRADING ID"].Value == item["TRADING ID"].Value then
                            itemInTrade = true
                            break
                        end
                    end

                    if not itemInTrade then

                        if currentTrade.Receiver:FindFirstChild("ACCEPTED") then
                            currentTrade.Receiver.ACCEPTED:Destroy()
                        end
                        if currentTrade.Sender:FindFirstChild("ACCEPTED") then
                            currentTrade.Sender.ACCEPTED:Destroy()
                        end

                        item:Clone().Parent = plrSlots
                    end
                end
            end
        end


    --Remove an item from the trade
    elseif instruction == "remove item from trade" then

        local item = data[1]

        if item.Parent == plr.Backpack or item.Parent == plr.Character then

            local currentTrade = nil
            for i, trade in pairs(ongoingTradesFolder:GetChildren()) do
                if trade.Sender.Value == plr.Name or trade.Receiver.Value == plr.Name then
                    currentTrade = trade
                    break
                end
            end

            if currentTrade then

                local plrSlots = currentTrade[plr.Name .. "'s offer"]

                for i, plrItem in pairs(plrSlots:GetChildren()) do
                    if plrItem["TRADING ID"].Value == item["TRADING ID"].Value then

                        if currentTrade.Receiver:FindFirstChild("ACCEPTED") then
                            currentTrade.Receiver.ACCEPTED:Destroy()
                        end
                        if currentTrade.Sender:FindFirstChild("ACCEPTED") then
                            currentTrade.Sender.ACCEPTED:Destroy()
                        end

                        plrItem:Destroy()
                        break
                    end
                end
            end
        end


    --Accept a trade
    elseif instruction == "accept trade" then

        local currentTrade = nil
        for i, trade in pairs(ongoingTradesFolder:GetChildren()) do
            if trade.Sender.Value == plr.Name or trade.Receiver.Value == plr.Name then
                currentTrade = trade
                break
            end
        end

        if currentTrade then
            local plrValue = currentTrade.Sender.Value == plr.Name and currentTrade.Sender or currentTrade.Receiver.Value == plr.Name and currentTrade.Receiver

            if plrValue then

                if not plrValue:FindFirstChild("ACCEPTED") then
                    local acceptedValue = Instance.new("StringValue")
                    acceptedValue.Name = "ACCEPTED"
                    acceptedValue.Parent = plrValue

                else
                    plrValue.ACCEPTED:Destroy()
                end
            end

            if currentTrade.Sender:FindFirstChild("ACCEPTED") and currentTrade.Receiver:FindFirstChild("ACCEPTED") then

                task.wait(config.TimeBeforeTradeConfirmed)

                if currentTrade.Sender:FindFirstChild("ACCEPTED") and currentTrade.Receiver:FindFirstChild("ACCEPTED") then

                    local senderPlr = game.Players[currentTrade.Sender.Value]
                    local senderSlots = currentTrade[senderPlr.Name .. "'s offer"]

                    local receiverPlr = game.Players[currentTrade.Receiver.Value]
                    local receiverSlots = currentTrade[receiverPlr.Name .. "'s offer"]

                    local senderTools = config.GetTools(senderPlr)
                    local receiverTools = config.GetTools(receiverPlr)

                    for i, senderTool in pairs(senderTools) do
                        for x, senderSlot in pairs(senderSlots:GetChildren()) do
                            if senderTool["TRADING ID"].Value == senderSlot["TRADING ID"].Value then
                                senderTool.Parent = receiverPlr.Backpack
                            end
                        end
                    end

                    for i, receiverTool in pairs(receiverTools) do
                        for x, receiverSlot in pairs(receiverSlots:GetChildren()) do
                            if receiverTool["TRADING ID"].Value == receiverSlot["TRADING ID"].Value then
                                receiverTool.Parent = senderPlr.Backpack
                            end
                        end
                    end

                    currentTrade:Destroy()
                end
            end
        end


    --Reject a trade
    elseif instruction == "reject trade" then

        for i, trade in pairs(ongoingTradesFolder:GetChildren()) do

            if trade.Sender.Value == plr.Name or trade.Receiver.Value == plr.Name then
                trade:Destroy()

                break
            end
        end
    end
end)