CC: Cannon mail [Client] - mail.lua

-- mail.lua

--[[--
    Data structure for mail files:
    {
        ["sender"] = (string),
        ["receivers"] = (table) {
            [1] = (string),
            [2] = (string),
            etc.
        },
        ["subject"] = (string),
        ["message"] = (string),
    }

    Printer page size: 25x21
--]]--

--(( Settings ))--

local filename = "mail.dat"
local drivePath = "back"

--(( Variables ))--

err = {
    missing_item = "No item inside the disk drive!",
    invalid_item = "The item in the disk drive is not a valid disk!",
}

local drive = peripheral.wrap(drivePath)
or error("Unable to wrap disk drive!")

--(( Functions ))--

-- write a letter
function writeMail(mail)
    if drive.hasData() then
        local path = fs.combine(drive.getMountPath(),filename)

        local file = fs.open(path,"w")
        file.write(textutils.serialize(mail))
        file.close()

        rs.setOutput("top",true)
        sleep(1)
        rs.setOutput("top",false)
    else
        error("No disk available!")
    end
end

-- get a formatted title for the mail
function getTitle(mail, page, pages)
    local title = '"'
    util.wordwrap(mail.subject, function(row) title=title..row end, 32, 0)
    title = title .. '" from '
    util.wordwrap(mail.sender, function(row) title=title..row end, 32, 0)

    if pages > 1 then
        title = title .. " (page " .. page .. " of " .. pages .. ")"
    end

    return title
end

-- prepare the mail for writing
function prepareMessage(data)
    local w,h = 25,21 -- size of page
    local rows = {}
    local message = data.message
    local offset = 0

    repeat
        util.wordwrap("From: "..data.sender, rows, w, 0)
        util.wordwrap("Subject: "..data.subject, rows, w, 1)
        table.insert(rows, string.rep("-",w))
        message = util.wordwrap(message, rows, w, h - #rows - 2 + offset)
        for i=1,h-#rows-1+offset do table.insert(rows, "") end
        table.insert(rows,666)

        offset = #rows
    until message == nil

    -- Go through 2nd time
    local pages = math.ceil(#rows/h)

    for i,row in ipairs(rows) do
        if row == 666 then
            local page = math.ceil(i/h)

            row = "[ Page " .. page .. " / " .. pages .. " ]--"
            row = string.rep("-",25-#row)..row

            -- apply change
            rows[i] = row
        end
    end

    return rows
end

function splitPages(rows)
    local h = 21 -- height of page
    local pages = {}

    for i,sRow in ipairs(rows) do
        local page = math.ceil(i/h)
        local nRow = i-(page-1)*h

        pages[page] = pages[page] or {}
        pages[page][nRow] = sRow
    end

    return pages
end

function getDrive()
    return drive
end

-- eof