Time

-- Real time clock using HTTP API by PaymentOption --
-- Freeware as long as proper credits are given --

-- Variables --
tTimeLinks = {
["Pacific Standard Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/na/pst.html", -- United States
["Eastern Standard Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/na/est.html", -- United States
["Central Standard Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/na/cst.html", -- United States
["Chinese Standard Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/asia/cst.html", -- China
["British Summer Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/eu/bst.html", -- England, Wales, Scotland, Ireland (United Kingdom)
-- Australia --
["Central Standard Time AU"] = "http://www.timeanddate.com/library/abbreviations/timezones/au/cst.html",
["Christmas Island Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/au/cxt.html",
["Eastern Standard Time AU"] = "http://www.timeanddate.com/library/abbreviations/timezones/au/est.html",
["Lord Howe Standard Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/au/lhst.html",
["Norfolk Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/au/nft.html",
["Western Standard Time"] = "http://www.timeanddate.com/library/abbreviations/timezones/au/wst.html"
}

tLocations = {
[1] = "United States",
[2] = "Australia",
[3] = "United Kingdom",
[4] = "China"
}

tSubLocations = {
    tUnitedStates = {
        [1] = "Pacific Standard Time",
        [2] = "Eastern Standard Time",
        [3] = "Central Standard Time"
    },
    tUnitedKingdom = {
        [1] = "British Summer Time"
    },
    tAustralia = {
        [1] = "Central Standard Time AU",
        [2] = "Christmas Island TIme",
        [3] = "Eastern Standard Time AU",
        [4] = "Lord Howe Standard TIme",
        [5] = "Norfolk Time",
        [6] = "Western Standard Time"
    },
    tChina = {
        [1] = "Chinese Standard Time"
    }
}

sArea = "" -- United States, China, United Kingdom, Australia.

nScreenWidth, nScreenHeight = term.getSize()
---------------

-- Input gathering methods --
function GetOption_Number( nOptionList_Size )
    term.setCursorBlink( true )

    local nStartingPosX, nStartingPosY = term.getCursorPos()
    local nInput = 0

    local sEvent, sNum = os.pullEvent( "char" )
    term.write( sNum )

    local function ResetCursor()
        term.setCursorPos( nStartingPosX, nStartingPosY )
        term.write( string.rep( " ", string.len( tostring( nInput ) ) ) )

        term.setCursorPos( nStartingPosX, nStartingPosY )
        GetOption_Number( nOptionList_Size )
    end

    if type( tonumber( sNum ) ) == "string" then
        ResetCursor()
    else
        nInput = tonumber( sNum )
    end

    if nInput then
        if nInput <= 0 or nInput > nOptionList_Size then
            ResetCursor()
        else
            term.setCursorBlink( false )
            return nInput
        end
    end
end

function GetArea( tLocationTable )
    term.setCursorPos( 2, 9 )
    term.write( "Pick an option: " )

    local nInput = GetOption_Number( #tLocationTable )
    sArea = tLocationTable[nInput]
end
-----------------------------

-- GUI piece methods --
function PrintBorder()
    term.setCursorPos( 1, 1 )
    term.write( "+" .. string.rep( "-", nScreenWidth - 2 ) .. "+" )

    for nHeight = 2, nScreenHeight - 1 do
        term.setCursorPos( 1, nHeight )
        term.write( "|" )

        term.setCursorPos( nScreenWidth, nHeight )
        term.write( "|" )
    end

    term.setCursorPos( 1, nScreenHeight )
    term.write( "+" .. string.rep( "-", nScreenWidth - 2 ) .. "+" )
end

function PrintLocations( tLocationTable )
    for nHeight = 2, #tLocationTable + 1 do
        term.setCursorPos( 2, nHeight )
        term.write( "[" .. nHeight - 1 .. "] " .. tLocationTable[nHeight - 1] )
    end
end

function Clear()
    term.clear()
    term.setCursorPos( 1, 1 )
end

function PrintCentered( nHeight, sString )
    term.setCursorPos( nScreenWidth/2 - string.len( sString )/2, nHeight )
    term.write( sString )
end
------------------------

-- Menu methods --
function GlobalLocationSelection_Menu()
    Clear()
    PrintBorder()
    PrintLocations( tLocations )

    local nInput = GetArea( tLocations )
end

function SubSelectionMenu_UnitedStates()
    Clear()
    PrintBorder()
    PrintLocations( tSubLocations.tUnitedStates )

    local nInput = GetArea( tSubLocations.tUnitedStates )
end

function SubSelectionMenu_Australia()
    Clear()
    PrintBorder()
    PrintLocations( tSubLocations.tAustralia)

    local nInput = GetArea( tSubLocations.tAustralia )
end

function SubSelectionMenu_UnitedKingdom()
    Clear()
    PrintBorder()
    PrintLocations( tSubLocations.tUnitedKingdom )

    local nInput = GetArea( tSubLocations.tUnitedKingdom )
end

function SubSelectionMenu_China()
    Clear()
    PrintBorder()
    PrintLocations( tSubLocations.tChina )

    local nInput = GetArea( tSubLocations.tChina )
end

function DisplayTime()
    Clear()
    PrintBorder()
    PrintCentered( 2, sArea )

    term.setCursorPos( 2, nScreenHeight - 1 )
    term.write( "[Change]" )

    while true do
        local sTime = GetTimeFromLine()
        PrintCentered( 9, sTime )

        os.startTimer( 0.3 )

        local sEvent, nKey = os.pullEvent()
        if sEvent == "key" and nKey == 28 then
            GlobalLocationSelection_Menu()
            CheckGlobalArea()
            DisplayTime()
        end
    end
end
------------------

-- Area check methods --
function CheckGlobalArea()
    if sArea == "United States" then
        SubSelectionMenu_UnitedStates()
    elseif sArea == "Australia" then
        SubSelectionMenu_Australia()
    elseif sArea == "United Kingdom" then
        SubSelectionMenu_UnitedKingdom()
    elseif sArea == "China" then
        SubSelectionMenu_China()
    end
end
------------------------

-- HTTP parsing methods --
function GetTimePage()
    local sRespone = nil
    local sLine = ""

    sResponse = http.get( tTimeLinks[sArea] )

    if sResponse then
        for nLine = 1, 31 do
            sLine = sResponse.readLine()
        end
        sResponse.close()

        return true, sLine
    else
        return false, nil
    end
end

function GetTimeFromLine()
    local bSuccess, sLine = GetTimePage()

    if bSuccess then
        if sArea == "Pacific Standard Time" then
            _, nTimePos = string.find( sLine, '<span id="ij0">' )
            nEndTimePos = string.find( sLine, '</span>', nTimePos )
        else
            _, nTimePos = string.find( sLine, 'class="big">' )
            nEndTimePos = string.find( sLine, '</span>', nTimePos )
        end

        local sTime = string.sub( sLine, nTimePos + 1, nEndTimePos - 1 )
        return sTime
    else
        return nil
    end
end
--------------------------

GlobalLocationSelection_Menu()
CheckGlobalArea()
DisplayTime()