chess (monitor)

--[[ Chess Watch

The fun way to watch Minecraft Chess :)

Written by NitrogenFingers
Art curtosy of NN(1998)
]]--

local monitorSide = "left"
local side = nil

local board = {
  --        a     b     c     d     e     f     g     h
  [8] = { "-C",  "-N",  "-B",  "-Q",  "-K",  "-B",  "-N",  "-C" },
  [7] = { "-p",  "-p",  "-p",  "-p",  "-p",  "-p",  "-p",  "-p" },
  [6] = { " ",  " ",  " ",  " ",  " ",  " ",  " ",  " " },
  [5] = { " ",  " ",  "",  " ",  " ",  " ",  " ",  " " },
  [4] = { " ",  " ",  " ",  " ",  " ",  " ",  " ",  " " },
  [3] = { " ",  " ",  " ",  " ",  " ",  " ",  " ",  " " },
  [2] = { "+p",  "+p",  "+p",  "+p",  "+p",  "+p",  "+p",  "+p" },
  [1] = { "+C",  "+N",  "+B",  "+Q",  "+K",  "+B",  "+N",  "+C" }
  --        a     b     c     d     e     f     g     h
}
local pawnList = {
    "(Q)",
    "/Q\\",
    "==="
}
local knightList = {
    " ,^. ",
    "(QQ'\\",
    "|QQ\\ ",
    "==== "
}
local bishopList = {
    " o  ",
    "(Q/)",
    "/QQ\\",
    "===="
}
local castleList = {
    "WWWW",
    "|QQ|",
    "/QQ\\",
    "===="
}
local queenList = {
    "www",
    "\\Q/",
    "(Q)",
    "/Q\\",
    "==="
}
local kingList = {
    "_+_",
    "\\Q/",
    "(Q)",
    "/Q\\",
    "==="
}

local backboard = {
        " _____     _____     _____     _____     ",
        "|     :::::     :::::     :::::     :::::|",
        "|     :::::     :::::     :::::     :::::|",
        "|     :::::     :::::     :::::     :::::|",
        "|:::::     :::::     :::::     :::::     |",
        "|:::::     :::::     :::::     :::::     |",
        "|:::::     :::::     :::::     :::::     |",
        "|     :::::     :::::     :::::     :::::|",
        "|     :::::     :::::     :::::     :::::|",
        "|     :::::     :::::     :::::     :::::|",
        "|:::::     :::::     :::::     :::::     |",
        "|:::::     :::::     :::::     :::::     |",
        "|:::::     :::::     :::::     :::::     |",
        "|     :::::     :::::     :::::     :::::|",
        "|     :::::     :::::     :::::     :::::|",
        "|     :::::     :::::     :::::     :::::|",
        "|:::::     :::::     :::::     :::::     |",
        "|:::::     :::::     :::::     :::::     |",
        "|:::::     :::::     :::::     :::::     |",
        "|     :::::     :::::     :::::     :::::|",
        "|     :::::     :::::     :::::     :::::|",
        "|     :::::     :::::     :::::     :::::|",
        "|:::::     :::::     :::::     :::::     |",
        "|:::::     :::::     :::::     :::::     |",
        "|:::::_____:::::_____:::::_____:::::_____|"
    }

function printBoard()
    mcall("clear")
    for i = 1, #backboard do
        mcall("setCursorPos", 9,7 + i)
        mcall("write", backboard[i])
    end

    for i = 1, 8 do
        for j = 1, 8 do
            printPiece(board[9-i][j], 13 + (j-1)*5, 10 + (i-1)*3)
        end
    end
end

function printPiece(piece, x, y)
    white = false
    if string.find(piece, "+") == 1 then white = true end

    piece = string.sub(piece, 2)
    list = nil

    if piece == "p" then list = pawnList
    elseif piece == "N" then list = knightList
    elseif piece == "B" then list = bishopList
    elseif piece == "C" then list = castleList
    elseif piece == "Q" then list = queenList
    elseif piece == "K" then list = kingList
    else return end

    for i=1,#list do
        local nextString = list[i]
        while nextString:find("Q") do
            if white then
                nextString = string.gsub(nextString, "Q", "#")
            else
                nextString = string.gsub(nextString, "Q", " ") end
        end
        mcall("setCursorPos", x - #nextString/2, y - #list + i)
        mcall("write", nextString)
    end
end

--A combination of the parseInput and the essentials of the makeMove method from chess.lua
function makeMove(input)
    local oldx = convertLetterToCoordinate(string.sub(input, 1, 1))
    local oldy = tonumber(string.sub(input, 2, 2))
    local newx = convertLetterToCoordinate(string.sub(input, 4, 4))
    local newy = tonumber(string.sub(input, 5, 5))

    if not oldx or not oldy or not newx or not newy then return end

    local oldsub = board[oldy][oldx]
    local newsub = board[newy][newx]

    board[newy][newx] = board[oldy][oldx]
    board[oldy][oldx] = " "

    --en passant is handled here
    if board[newy][newx] == " " and math.abs(oldx-newx) == 1 and
      board[oldy][oldx]:sub(2) == "p" and board[oldy][newx]:sub(2) == "p" then
        board[oldy][newx] = " "
    end

    --Castling is handled here
    if board[newy][newx] == "+K" then
        if newx - oldx == 2 then
            board[1][6] = board[1][8]
            board[1][8] = " "
        elseif newx - oldx == -2 then
            board[1][4] = board[1][1]
            board[1][1] = " "
        end
    end
    if board[newy][newx] == "-K" then
        blackKing = { x = newx, y = newy }
        if newx - oldx == 2 then
            board[8][6] = board[8][8]
            board[8][8] = " "
        elseif newx - oldx == -2 then
            board[8][4] = board[8][1]
            board[8][1] = " "
        end
    end
end

function convertLetterToCoordinate(input)
  if input=="a" then return 1
  elseif input=="b" then return 2
  elseif input=="c" then return 3
  elseif input=="d" then return 4
  elseif input=="e" then return 5
  elseif input=="f" then return 6
  elseif input=="g" then return 7
  elseif input=="h" then return 8
  else return nil end
end

--Runs a term application on the monitor. A time-saving method, and we only ever use 3 parameters.
function mcall(f,p1,p2,p3)
    peripheral.call(monitorSide, f, p1, p2, p3)
end

--Finds the side the modem is on, and opens it
function openModem()
    for i=1,#rs.getSides() do
        if peripheral.isPresent(rs.getSides()[i]) and peripheral.getType(rs.getSides()[i]) == "modem" then
            side = rs.getSides()[i]
            rednet.open(side)
            return true
        end
    end
    return false
end
--Finds the side the monitor is on
function findMonitor()
    for i=1,#rs.getSides() do
        if peripheral.isPresent(rs.getSides()[i]) and peripheral.getType(rs.getSides()[i]) == "monitor" then
            monitorSide = rs.getSides()[i]
            return true
        end
    end
    return false
end

--This promotes a pawn from a network message
function handleRemotePawnPromotion(msg)
    local x = tonumber(string.sub(msg, 1, 1))
    local y = tonumber(string.sub(msg, 2, 2))
    local piece = string.sub(msg, 3)

    board[y][x] = piece
    movesMade[#movesMade].promotion = string.sub(msg, 4)
end

function runMonitor()
    while true do
        printBoard()
        local proMsg = nil
        local key,msg = rednet.receive()
        if msg == "#Q" then
            break
        elseif string.find(msg, "#P") == 1 then
            proMsg = string.sub(msg, 3)
        else
            makeMove(msg)
            if proMsg then handleRemovePawnPromotion(proMsg) end
        end
    end

end

function prepareMonitor()

    --This short program is used for monitor displays
    term.write("Enter ID of host: ")
    local number = tonumber(io.read())
    if not number then
        print("Bad input!")
        return
    end

    if not openModem() then
        print("No modem on your computer!")
        return
    end

    if not findMonitor() then
        print("No monitor on your computer!")
        return
    end

    rednet.send(number, "#M")
    local key,msg = rednet.receive(5)

    if not key then
        print("No response.")
        return
    end

    if msg == "#Y" then
        print("Accepted- starting monitor application")
        runMonitor()
    end
end

prepareMonitor()