Todo List For Computer Craft Advance Computers

--shopping list created
-- by gunnar jessee/gnoor1s

--[[
    Create a list of tasks
    Being able to add tasks to a list
    Being able to remove a task from the list
    Needs a logging api

    tasks will be stored in an array. each task will be able to
        have a remove/pop task from the list
    tasks will have an idea to them

]]

tasks = {}
appRunning = true

function split(pString, pPattern)
    local Table = {}  -- NOTE: use {n = 0} in Lua-5.0
    local fpat = "(.-)" .. pPattern
    local last_end = 1
    local s, e, cap = pString:find(fpat, 1)
    while s do
           if s ~= 1 or cap ~= "" then
          table.insert(Table,cap)
           end
           last_end = e+1
           s, e, cap = pString:find(fpat, last_end)
    end
    if last_end <= #pString then
           cap = pString:sub(last_end)
           table.insert(Table, cap)
    end
    return Table
 end

function save_data( arr )
    local dataFile = fs.open('tasks', 'w')

    for i, k in pairs(arr) do
        dataFile.write( arr[i]['task'] .. ',' )
    end

    dataFile.flush()
    dataFile.close()
end

function load_data()
    if fs.exists('tasks') then
        local dataFile = fs.open('tasks', 'r')
        local dataString = dataFile.readAll()
        print(split(dataString, ','))
        local splitted = split(dataString, ',')
        for i, k in pairs(splitted) do
            print(splitted[i])
            sleep(.1)
            add_task(task_info(splitted[i]), tasks)
        end
    end
end

-- UTILITIES
function clear_screen(col)
    term.setBackgroundColor(col)
    term.clear()
    term.setCursorPos(1, 1)
end -- inperfect

-- set y position and startX position based on character count of text
function center_text(text, y_pos)
    char_count = string.len( text )
    screen_width = term.getSize()
    term.setCursorPos((screen_width/2) - (char_count/2), y_pos)
    term.write( text .. '\n' )
end

function set_y( y_pos )
    term.setCursorPos(1, y_pos)
end

-- Returns info about task create
-- when referencing table, do as (table[i][N])
-- task, id
function task_info( info_text )
    local info = {
        ['task'] = info_text
    }
    return info
end

function print_at_line( text, y_pos )
    set_y( y_pos )
    term.clearLine()
    set_y( y_pos )
    term.write( text )
end

--task data is referred here
--has to references a array called
function add_task( task_data, arr )
    table.insert( arr, task_data )
    save_data( arr )
end

function draw_list()

    screen_width, screen_height = term.getSize()
    clear_screen(colors.blue)
    term.setBackgroundColor(colors.blue)
    center_text("Task List", 2)
    for i, v in pairs(tasks) do
        set_y(4 + i)
        term.setBackgroundColor(colors.lightBlue)
        term.clearLine()
        set_y(4 + i)
        tasks[i]['line'] = i + 4
        print("["..i.. "]"..tasks[i]['task'])
    end
    term.setBackgroundColor(colors.green)
    term.setCursorPos(1, screen_height)
    term.write("[+]")
    term.setCursorPos(screen_width-2, screen_height)
    term.setBackgroundColor(colors.red)
    term.write("[X]")
end

function check_remove_at(y_pos)
    for i, k in pairs(tasks) do
        if tasks[i]['line'] == y_pos then
            table.remove(tasks, i)
        end
    end
end

-- PAGES

function render_add_task()
    local page_running = true

    clear_screen(colors.blue)
    center_text('Add todo', 2)
    set_y(5)
    print('Enter Task Name')
    input = read()
    add_task(task_info(input), tasks)
    draw_list() -- goes to page
    return
end

function render_list()

    screen_width, screen_height = term.getSize()
    draw_list()
    while appRunning do
        local event, button, x, y = os.pullEvent( "mouse_click" )

        if y >= 4 and y <= screen_height - 1 then
            check_remove_at(y)
            save_data( tasks )
            draw_list()
        end

        if y == screen_height and x < 4 then
            render_add_task()
        end

        if y == screen_height and x > screen_width - 4 then
            clear_screen(colors.black)
            set_y(1)
            print("Programming has exited safely")
            return
        end

    end

end

-- All running code & Variables
function run()
    load_data()
    render_list()
end


run()