Bejeweled in ComputerCraft

local board = {}
local score = 0
local time = 600

local gems = {
    {'%.', '%%', color = colors.yellow},
    {'$.', '$$', color = colors.lime},
--  {'&.', '&&', color = colors.orange},
    {'#.', '##', color = colors.red},
    {'@a', '@@', color = colors.magenta},
    {'/\\','\\/', color = colors.lightBlue}
}

local selection
local draw, drawGem, drawScore, drawTime, animSwap

local running = true

local function fillBoard(width, height)
    for y = 1, height do
        board[y] = {}
        for x = 1, width do
            board[y][x] = math.random(#gems)
        end
    end

    setmetatable(board, {__call = function(self, x, y, value)
        if not self[y] then return end
        if not self[y][x] then return end
        self[y][x] = value or self[y][x]
        return self[y][x]
    end})

    board.width = width
    board.height = height
end

local function gemArea(x, y)
    return x*3 - 1, y*3 - 1, 2, 2
end

local function checkArea(x, y, ax, ay, aw, ah)
    return
        x >= ax and
        x < ax + aw and
        y >= ay and
        y < ay + ah
end

local function findMatch(ox, oy)
    local value = board(ox, oy)
    if value == 0 then return end
    local rowTotal = 0
    local colTotal = 0
    local rowMatches = {}
    local colMatches = {}

    local function checkSpace(x, y, isRow)
        if board(x, y) == value then
            if isRow then
                rowTotal = rowTotal + 1
                table.insert(rowMatches, {x=x, y=y})
            else
                colTotal = colTotal + 1
                table.insert(colMatches, {x=x, y=y})
            end
            return true
        end
    end

    for x=ox, 1, -1 do
        if not checkSpace(x, oy, true) then break end
    end
    for x=ox + 1, board.width, 1 do
        if not checkSpace(x, oy, true) then break end
    end
    for y=oy, 1, -1 do
        if not checkSpace(ox, y) then break end
    end
    for y=oy + 1, board.height, 1 do
        if not checkSpace(ox, y) then break end
    end

    local matches = {}
    local function addFrom(tab, cond)
        if cond then
            for i=1, #tab do
                table.insert(matches, tab[i])
            end
        end
    end
    addFrom(rowMatches, rowTotal >= 3)
    addFrom(colMatches, colTotal >= 3)

    if #matches >= 3 then
        return matches
    end
end

local function replaceGems()
    local blanks
    repeat
        blanks = false
        for bx=1, board.width do
            for by=1, board.height do
                if board(bx, by) == 0 then
                    for y=by - 1, 0, -1 do
                        if y > 0 then
                            board(bx, y + 1, board(bx, y))
                        else
                            board(bx, y + 1, math.random(#gems))
                        end
                        drawGem(bx*3-1, (y+1)*3-1, gems[board(bx, y + 1)])
                    end
                    sleep(0.05)
                    blanks = true
                end
            end
        end
    until not blanks
end

local function clearMatches()
    draw()

    local redo = true
    local scoreInc = 1

    while redo do
        redo = false
        local totalMatches = {}
        for bx=1, board.width do
            for by=1, board.height do
                local matches = findMatch(bx, by)

                if matches then
                    for i=1, #matches do
                        local m = matches[i]
                        totalMatches[m.x..','..m.y] = board(m.x, m.y)
                        drawGem(m.x*3 - 1, m.y*3 - 1, gems[board(m.x, m.y)], colors.white)
                    end
                end
            end
        end
        sleep(0.2)
        for pos, id in pairs(totalMatches) do
            local x,y = pos:match('(%d+),(%d+)')
            board(tonumber(x), tonumber(y), 0)
            redo = true
            score = score + scoreInc
            scoreInc = scoreInc + 1

            drawGem(x*3 - 1, y*3 - 1)
            drawScore()
            sleep(0.1)
        end

        if redo then
            replaceGems()
        end
    end
end

local function update(ev, p1, p2, p3)
    if ev == 'mouse_click' or ev == 'mouse_drag' then
        local b, mx, my = p1, p2, p3

        -- it's like the brooklyn bridge up in this yo
        ;(function()
            for bx=1, board.width do
                for by=1, board.height do
                    if checkArea(mx, my, gemArea(bx, by)) then
                        if ev == 'mouse_click' then
                            selection = {bx, by}
                            return
                        elseif ev == 'mouse_drag' and selection then
                            local s = selection
                            local dist = ((bx - s[1])^2 + (by - s[2])^2)^.5
                            if dist == 1 then
                                local cur = board(bx, by)
                                animSwap(bx*3-1, by*3-1, s[1]*3-1, s[2]*3-1, cur, board(unpack(s)))

                                board(bx, by, board(unpack(s)))
                                board(s[1], s[2], cur)

                                clearMatches()

                                selection = nil
                                return
                            end
                        end
                    end
                end
            end
        end)()
    elseif ev == 'key' and p1 == keys.backspace then
        running = false
    end
end

local function updateTime()
    while time > 0 do
        time = time - 1
        drawTime()
        sleep(0.1)
    end
end

function drawScore()
    local t = term
    local score = tostring(score)

    t.setCursorPos(30, 2)
    t.setTextColor(colors.yellow)
    t.write('SCORE: '..score)
end

function drawTime()
    local t = term

    t.setCursorPos(30, 4)
    t.setTextColor(colors.yellow)
    t.write('TIME:  '..time..'     ')
end

function drawGem(x, y, gem, color)
    local t = term
    if t.isColor() and gem then
        t.setTextColor(color or gem.color)
    end
    t.setCursorPos(x, y)
    t.write(gem and gem[1] or '  ')
    t.setCursorPos(x, y + 1)
    t.write(gem and gem[2] or '  ')
end

function animSwap(x1, y1, x2, y2, v1, v2)
    for x=x1, x2, x1 < x2 and 1 or -1 do
        for y=y1, y2, y1 < y2 and 1 or -1 do
            local ox, oy = x2 - x + x1, y2 - y + y1
            drawGem(x, y, gems[v1])
            drawGem(ox, oy, gems[v2])
            sleep(0.05)
            drawGem(x, y)
            drawGem(ox, oy)
        end
    end
end

function draw()
    local t = term

    t.setBackgroundColor(colors.black)
    t.clear()

    for x=1, board.width do
        for y=1, board.height do
            drawGem(x*3 - 1, y*3 - 1, gems[board(x, y)])
        end
    end

    drawScore()
end

local function pregame()
    draw()
    drawTime()

    local t = term

    local function sw(y, text)
        t.setCursorPos(30, y)
        textutils.slowWrite(text)
    end

    t.setTextColor(colors.yellow)
    t.setCursorPos(30, 6)
    sw(6, 'PRESS ANY KEY')
    sw(7, 'WHEN READY')

    repeat
        local ev = os.pullEvent()
    until ev == 'key' or ev == 'mouse_click'

    sw(7, '          ')
    sw(6, 'READY        ')
    sleep(0.1)
    sw(6, '             ')
    sw(6, 'SET          ')
    sw(6, '             ')
    sleep(math.random()*1.5 + 0.5)

    t.setCursorPos(30, 6)
    t.write('GO')
    sleep(0.2)
    sw(6, '  ')
end

local function gameOver()
    local t = term
    t.setTextColor(colors.yellow)

    local function sw(y, text)
        t.setCursorPos(30, y)
        textutils.slowWrite(text)
    end

    sw(6, 'PRESS ANY KEY')
    sw(7, 'TO CONTINUE')

    repeat
        local ev = os.pullEvent()
    until ev == 'key' or ev == 'mouse_click'

    t.setBackgroundColor(colors.black)
    t.setCursorPos(1,1)
    t.clear()
end

local function main()
    while running do
        local events = {os.pullEvent()}
        if events[1] ~= 'timer' then
            draw()
        end
        update(unpack(events))
    end
end

fillBoard(8, 6)
pregame()

parallel.waitForAny(main, updateTime)

gameOver()