plan_war/core.lua

core = {}
core.block = {}
core.score = 0
core.best = 0
love.filesystem.setIdentity('2048')

local function get_best() 
    if not love.filesystem.exists('best') then
        core.best = 0
        return
    end
    core.best = love.filesystem.read('best')
    core.best = tonumber(core.best)
end

function core.initial()
    core.block = {}
    local pos1 = love.math.random(1, 16)
    local pos2
    while true do
        pos2 = love.math.random(1, 16)
        if pos2 ~= pos1 then break end
    end

    local val
    val = love.math.random()
    if val < 0.8 then val = 2 else val = 4 end
    core.block[pos2] = val
    core.score = 0
end

function core.set_best()
    if core.score > core.best then
        core.best = core.score
        local ret, err = love.filesystem.write('best', core.best)
    end
end

function core.tblclone(t1, num)
    local t2 = {}
    for i = 1, num do
        t2[i] = t1[i]
    end
    return t2
end

function core.isfull(testtbl)
    local block
    if testtbl then block = testtbl else block = core.block end

    for i = 1, 16 do
        if not  block[i] then return false end
    end
    return true
end

local function combine(lstart, lend, lstep, rstart, rend, rstep, flag, testtbl)
    local index
    local tflag, block
    if testtbl then
        tflag = true
        block = testtbl
    else
        block = core.block
    end
    local cflag = false
    for i = lstart, lend, lstep do
        for j = rstart, rend, rstep do
            if flag == 'up' then index = (i - 1) * 4 + j
            elseif flag == 'down' then index = (i + 1) * 4 + j
            elseif flag == 'left' then index = i * 4 + j - 1
            else index = i * 4 + j + 1 end
            
            if block[index] and block[i * 4 + j] and block[index] == block[i * 4 + j] and block[index] < 2048 then
                cflag = true
                if tflag then return cflag end
                block[index] = 2 * block[i * 4 + j]
                block[i* 4 + j] = nil
                core.score = core.score + block[index]
            end
        end
    end
    return cflag
end

local function move(lstart, lned, lstep, rstart, rend, rstep, flag)
    local mflag = false
    local index, kstart, kend, kstep
    for i = lstart, lend, lstep do
        for j = rstart, rend, rstep do
            if flag == 'up' then 
                kstart = 0
                kend = i - 1
                kstep = 1
            elseif flag == 'down' then
                kstart = 3
                kend = i + 1
                kstep = -1
            elseif flag == 'left' then
                kstart = 1
                kend = j - 1
                kstep = 1
            else 
                kstart = 4
                kend = j + 1
                kstep = 1
            end

            for k = kstart, kend, kstep do
                if flag == 'up' or flag == 'down' then index = k *4 +j
                else index = i * 4 + kend
                if not core.block[index] and core.block[i * 4 + j] then
                    core.block[index] = core.block[i * 4 + j]
                    core.block[i * 4 + j] = nil
                    mflag = true
                    break
                end
            end
        end
    end
    return mflag
end
end

local function do_tsk(lstart, lend, lstep, rstart, rend, rstep, flag, testtbl)
    if testtbl then return combine(lstart, lend, lstep, rstart, rend, rstep, flag, testtbl) end
    local mret = move(lstart, lend, lstep, rstart, rend, rstep, flag)
    local cret = combine(lstart, lend, lstep, rstart, rend, rstep, flag)

    if not mret and not cret then return false end
    move(lstart, lend, lstep, rstart, rend, rstep, flag)
    return true
end

function core.up_move(testtbl)
    return do_tsk(1,3,1,1,4,1, 'up', testtbl)
end
function core.down_move(testtbl)
    return do_tsk(2, 0, -1, 1, 4, 1,"down", testtbl)
end
function core.left_move(testtbl)
    return do_tsk(0, 3, 1, 2, 4, 1, "left", testtbl)
end
function core.right_move(testtbl)
    return do_tsk(0, 3, 1, 3, 1, -1, "right", testtbl)
end

function core.new_block()
    local val = love.math.random()
    if val < 0.8 then val = 2 else val = 4 end
    local empty_tbl = {}
    for i = 1, 16 do
        if not core.block[i] then
            table.insert(empty_tbl, i)
        end
    end
    if #empty_tbl == 1 then
        return {index = empty_tbl[1], value = val}
    end
    local pos = love.math.random(1, #empty_tbl)
    return {index = empty_tbl[pos], value = val}
end
get_best()
return core