Menusys (ComputerCraft)

-- This is for ComputerCraft
-- OpenComputers version here: http://pastebin.com/41g8zs6R
-- Also, this requires "corefunc"
-- http://pastebin.com/ShiTjX9W

--[[
Copyright (c) 2016, Zsolt Tóth

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

]]

os.loadAPI("corefunc")

-- ONE DIMENSIONAL MENUS

function displayChoice(choices,state,intro,outro)
    term.clear()
    term.setCursorPos(1,1)
    -- Write out the intro.
    if intro ~= nil then
        if type(intro) == "function" then
            intro()
        else
            print(intro .. "\n")
        end
    else
        print("\n\n")
    end
    -- Present the choices
    for key,value in ipairs(choices) do
        x0,y0 = term.getSize()
        x1,y1 = term.getCursorPos()
        y1 = y1 + 1
        if type(value) == "function" then
            x1 = math.floor((x0 / 2) - ((string.len(value()) + 2) / 2))
        else
            x1 = math.floor((x0 / 2) - ((string.len(value) + 2) / 2))
        end
        term.setCursorPos(x1,y1)
        if key == state then
            term.setTextColor(colors.black)
            term.setBackgroundColor(colors.white)
            if type(value) == "function" then
                 term.write(" " .. value() .. " ")
            else
                term.write(" " .. value .. " ")
            end
            term.setTextColor(colors.white)
            term.setBackgroundColor(colors.black)
        else
            if type(value) == "function" then
                 term.write(" " .. value() .. " ")
            else
                term.write(" " .. value .. " ")
            end
        end
    end
    -- Write out the outro.
    if outro ~= nil then
        if type(outro) == "function" then
            outro()
        else
            print("\n\n" .. outro)
        end
    else
        print("\n\n")
    end
end

function displayMenu(choices,intro,outro,init)
    local status = 1
    if init ~= nil then
        status = init
    end
    local statmax = tablelength(choices)
    local update = false
    displayChoice(choices,status,intro,outro)
    while true do
        local event, key, isHeld = os.pullEvent("key")
        if key == keys.enter or key == space or key == numPadEnter then
            return status
        elseif key == keys.backspace then
            return 0
        elseif key == keys.up or key == keys.left then
            status = status - 1
            update = true
        elseif key == keys.down or key == keys.right then
            status = status + 1
            update = true
        end
        if update == true then
            status = status % statmax
            if status <= 0 then
                status = statmax
            end
            displayChoice(choices,status,intro,outro)
            update = false
        end
    end
end

-- TWO-DIMENSIONAL MENUS


function displayChoiceMult(choices,xstate,ystate,intro,outro,sizex)
    term.clear()
    term.setCursorPos(1,1)
    x0,y0 = term.getSize()
    x0 = math.floor(x0 / sizex) -- We are going to divide by segments.
    -- Write out the intro.
    if intro ~= nil then
        if type(intro) == "function" then
            intro()
        else
            print(intro .. "\n")
        end
    else
        print("\n\n")
    end
    -- Present the choices
    for ykey,yvalue in ipairs(choices) do
        x1,y1 = term.getCursorPos()
        y1 = y1 + 1
        for xkey,xvalue in ipairs(yvalue) do
            if type(xvalue) == "function" then
                x1 = math.floor( (x0 / 2) - ((string.len(xvalue()) + 2) / 2) + (x0 * (xkey - 1) ) )
            else
                x1 = math.floor( (x0 / 2) - ((string.len(xvalue) + 2) / 2) + (x0 * (xkey - 1) ) )
            end
            term.setCursorPos(x1,y1)
            if ykey == ystate and xkey == xstate then
                term.setTextColor(colors.black)
                term.setBackgroundColor(colors.white)
                if type(xvalue) == "function" then
                    term.write(" " .. xvalue() .. " ")
                else
                    term.write(" " .. xvalue .. " ")
                end
                term.setTextColor(colors.white)
                term.setBackgroundColor(colors.black)
            else
                if type(xvalue) == "function" then
                    term.write(" " .. xvalue() .. " ")
                else
                    term.write(" " .. xvalue .. " ")
                end
            end
        end
    end
    -- Write out the outro.
    if outro ~= nil then
        if type(outro) == "function" then
            outro()
        else
            print("\n\n" .. outro)
        end
    else
        print("\n\n")
    end
end

function displayMenuMult(choices,intro,outro,initx,inity)
    local x_status = 1
    local y_status = 1
    if initx ~= nil then
        x_status = initx
    end
    if inity ~= nil then
        y_status = inity
    end
    local y_statmax = tablelength(choices)
    local x_size = 0
     for ykey,yvalue in ipairs(choices) do
         local temp = tablelength(yvalue)
         if temp > x_size then
             x_size = temp
         end
     end
    local update = false
    displayChoiceMult(choices,x_status,y_status,intro,outro,x_size)
    while true do
        local event, key, isHeld = os.pullEvent("key")
        if key == keys.enter or key == space or key == numPadEnter then
            return x_status,y_status
        elseif key == keys.backspace then
            return 0,0
        elseif key == keys.up then
            y_status = y_status - 1
            update = true
        elseif key == keys.left then
            x_status = x_status - 1
            update = true
        elseif key == keys.down then
            y_status = y_status + 1
            update = true
        elseif key == keys.right then
            x_status = x_status + 1
            update = true
        end
        if update == true then
            y_status = y_status % y_statmax
            if y_status <= 0 then
                y_status = y_statmax
            end
            local x_statmax = tablelength(choices[y_status])
            x_status = x_status % x_statmax
            if x_status <= 0 then
                x_status = x_statmax
            end
            displayChoiceMult(choices,x_status,y_status,intro,outro,x_size)
            update = false
        end
    end
end