terrarlua

local sides = {"left","right","up","down","forward","back"}
for _,v in ipairs(sides) do
  if peripheral.getType(v) == "modem" then
    rednet.open(v)
  end
end
local sFile = fs.open("world", "w")
local chunk = 0
local termW, termH = term.getSize()
local midW, midH = math.floor(termW/2), math.floor(termH/2)
local xPos, yPos = 0, 51
local pDir = ">"
local blockinfo = {
["bedrock"] = 128,
["stone"] = 256,
["dirt"] = 4096,
["grass"] = 32,
["air"] = 32768
}
world = nil
local blocks = {}
blocks[0] = "bedrock"
blocks[1] = "bedrock"
for i = 2, 24 do
        blocks[i] = "stone"
end
for i = 25, 40 do
        blocks[i] = "dirt"
end
for i = 41, 49 do
        blocks[i] = "grass"
end
blocks[50] = "air"
function generateWorld()
        local sFile = fs.open("world", "w")
        --sFile.writeLine("{")
        for x = -midW - 3, midW + 3 do
                sFile.writeLine("  [" .. tostring(x) .. "] = {")
                for y = 1, 50 do
                        sFile.writeLine("    [" .. tostring(y) .. "] = \"" .. tostring(blocks[math.random(y/1.2, y)]) .. "\",")
                end
                for y = 51, 100 do
                        sFile.write("    [" .. tostring(y) .. "] = \"air\"")
                        if y == 100 then
                                sFile.writeLine("")
                        else
                                sFile.writeLine(",")
                        end
                end
                if x == midW + 3 then
                        sFile.writeLine("  }")
                else
                        sFile.writeLine("  },")
                end
        end
        --sFile.writeLine("}")
        sFile.close()
end

function displayWorld()
        term.setBackgroundColor(colors.black)
        term.clear()
        term.setCursorPos(midW + 1, midH + 1)
        term.setBackgroundColor(colors.lightBlue)
        term.write(pDir)
        for x = xPos - midW, xPos + midW do
                for y = (yPos > 100 - midH) and 100 or yPos + midH, (yPos <= midH) and 1 or yPos - midH, -1 do
                        if world[x][y] ~= "air" then
                                term.setCursorPos(xPos + midW - x + 1, midH + yPos - y + 1)
                                term.setBackgroundColor(blockinfo[world[x][y]])
                                term.write(" ")
                        end
                end
        end
end

function updateWorld()
        world = nil
        local lFile = fs.open("world", "r")
        loadstring("world = {\n" .. lFile.readAll() .. "\n}")()
        lFile.close()
        if not world[xPos - midW - 3] or not world[xPos + midW + 3] then
                local cFile = fs.open("world", "r")
                local temp = cFile.readAll()
                cFile.close()
                local sFile = fs.open("world", "w")
                if not world[xPos - midW - 3] then
                        sFile.writeLine("  [" .. tostring(xPos - midW - 3) .. "] = {")
                        for y = 1, 50 do
                                sFile.writeLine("    [" .. tostring(y) .. "] = \"" .. tostring(blocks[math.random(y/1.2, y)]) .. "\",")
                        end
                        for y = 51, 100 do
                                sFile.write("    [" .. tostring(y) .. "] = \"air\"")
                                if y == 100 then
                                        sFile.writeLine("")
                                else
                                        sFile.writeLine(",")
                                end
                        end
                        sFile.writeLine("  },")
                        sFile.writeLine(temp)
                elseif not world[xPos + midW + 3] then
                        sFile.writeLine(temp .. ",")
                        sFile.writeLine("  [" .. tostring(xPos + midW + 3) .. "] = {")
                        for y = 1, 50 do
                                sFile.writeLine("    [" .. tostring(y) .. "] = \"" .. tostring(blocks[math.random(y/1.2, y)]) .. "\",")
                        end
                        for y = 51, 100 do
                                sFile.write("    [" .. tostring(y) .. "] = \"air\"")
                                if y == 100 then
                                        sFile.writeLine("")
                                else
                                        sFile.writeLine(",")
                                end
                        end
                        sFile.writeLine("  }")
                end
                sFile.close()
        end
end

generateWorld()
while true do
        updateWorld()
        displayWorld()
        term.setCursorPos(1, 1)
        term.write(tostring(xPos) .. "," .. tostring(yPos))
        sleep(.05)
        local events = {os.pullEvent()}
    if events[1]=="key" or events[1] == "rednet_message" then
                if events[2] == 200 or tonumber(events[3]) == 200 then --up
                        pDir = "^"
                        if world[xPos][yPos + 1] == "air" then
                                yPos = yPos + 1
                        end
                elseif events[2] == 205 or tonumber(events[3]) == 205 then --right
                        pDir = ">"
                        if world[xPos - 1][yPos] == "air" then
                                xPos = xPos - 1
                        end
                elseif events[2] == 208 or tonumber(events[3]) == 208 then --down
                        pDir = "v"
                        if world[xPos][yPos - 1] == "air" then
                                yPos = yPos - 1
                        end
                elseif events[2] == 203 or tonumber(events[3]) == 203 then --left
                        pDir = "<"
                        if world[xPos + 1][yPos] == "air" then
                                xPos = xPos + 1
                        end
                end
                if events[2] == 17 or tonumber(events[3]) == 17 then
                        pDir = "^"
                elseif events[2] == 30 or tonumber(events[3]) == 30 then
                        pDir = "<"
                elseif events[2] == 31 or tonumber(events[3]) == 31 then
                        pDir = "v"
                elseif events[2] == 32 or tonumber(events[3]) == 32 then
                        pDir = ">"
                end
                if events[2] == 45 or tonumber(events[3]) == 45 then
                        local changeB = "air"
                        local oTemp = fs.open("temp", "w")
                        local changeX, changeY = nil, nil
                        local ready = false
                        if pDir == "^" then
                                changeX, changeY = xPos, yPos + 1
                        elseif pDir == ">" then
                                changeX, changeY = xPos - 1, yPos
                        elseif pDir == "v" then
                                changeX, changeY = xPos, yPos - 1
                        elseif pDir == "<" then
                                changeX, changeY = xPos + 1, yPos
                        end
                        if world[changeX][changeY] ~= "bedrock" then
                                for line in io.lines("world") do
                                        if line:sub(3, 4 + #tostring(changeX)) == "[" ..tostring(changeX) .. "]" then
                                                ready = true
                                        end
                                        if ready and line:sub(6, 5 + #tostring(changeY)) == tostring(changeY) then
                                                oTemp.writeLine("    [" .. tostring(changeY) .. "] = \"" .. changeB .."\",")
                                                ready = false
                                        else
                                                oTemp.writeLine(line)
                                        end
                                end
                                oTemp.close()
                                oTemp = fs.open("temp", "r")
                                local temp = oTemp.readAll()
                                oTemp.close()
                                local sFile = fs.open("world", "w")
                                sFile.write(temp)
                                sFile.close()
                        end
                end
                if events[2] == 46 or tonumber(events[3]) == 46 then
                        local changeB = "stone"
                        local oTemp = fs.open("temp", "w")
                        local changeX, changeY = nil, nil
                        local ready = false
                        if pDir == "^" then
                                changeX, changeY = xPos, yPos + 1
                        elseif pDir == ">" then
                                changeX, changeY = xPos - 1, yPos
                        elseif pDir == "v" then
                                changeX, changeY = xPos, yPos - 1
                        elseif pDir == "<" then
                                changeX, changeY = xPos + 1, yPos
                        end
                        if world[changeX][changeY] == "air" then
                                for line in io.lines("world") do
                                        if line:sub(3, 4 + #tostring(changeX)) == "[" ..tostring(changeX) .. "]" then
                                                ready = true
                                        end
                                        if ready and line:sub(6, 5 + #tostring(changeY)) == tostring(changeY) then
                                                oTemp.writeLine("    [" .. tostring(changeY) .. "] = \"" .. changeB .."\",")
                                                ready = false
                                        else
                                                oTemp.writeLine(line)
                                        end
                                end
                                oTemp.close()
                                oTemp = fs.open("temp", "r")
                                local temp = oTemp.readAll()
                                oTemp.close()
                                local sFile = fs.open("world", "w")
                                sFile.write(temp)
                                sFile.close()
                        end
                end
        end
end