AutoUpdate

--Auto Updater
--pastebin.com/3K8mAXvf

--[[TODO LIST
01. TODO check file for corruption. Check size and type of values.
02. TODO set a limit for the number of programs that can be managed.
03. TODO fix excess characters after read()/event.keypress() functions.
04. TODO include optional monitor functionality.
05. TODO embed some clearer instructions.
06. TODO write some comments in this code :\ .
07. TODO transfer Menu instructions to a separate screen to make more room for the list
]]

function Main()
    --check for a save file
    if fs.exists("UpdateList.txt") == false then --If no program list exists then...
        UpdateProgram("viF3LUGT", "UpdateList.txt") --... download it
    end

    --wait for user input
    if CountdownBoolPrompt("Do you wish to view or change the settings?",5) then --..ask if the user wants to change the settings
        SaveCSV(Menu(LoadCSV("UpdateList.txt")), "UpdateList.txt") --load the old list, run the menu, save the new settings
    end

    --Open and download the list of programs
    programsList = LoadCSV("UpdateList.txt")

    --update programs
    term.clear() term.setCursorPos(1,1)
    for program = 1,#programsList do --for all the listed programs...
        if programsList[program][3] == true then --if the program is marked for update...
            UpdateProgram(programsList[program][1], programsList[program][2])
        end
    end

    --run boot programs
    for program = 1,#programsList do --for all the listed programs...
        if programsList[program][4] == true then --if the program is marked for run...
            RunProgram(programsList[program][2])
        end
    end
end

function Menu(menuTable) --allows user to edit settings. returns a table of programs and settings
    --find current selection
    local currentSelection = 1
    --if #menuTable == 0 then --if there are no menu items..
    --  menuTable[1] = GetNewPaste() --..get one
    --end
    local menuLength = #menuTable

    repeat
        --print the menu items
        term.clear() term.setCursorPos(1,1)
        print("Arrow keys to navigate. 'H' for help. 'Enter' to exit.")
        local firstItemCol, firstItemRow = term.getCursorPos()
        for menuRow = 1, menuLength do
            --term.setCursorPos(1, menuRow+firstItemRow-1)
            local printString = "  " .. menuTable[menuRow][1] .. " " .. menuTable[menuRow][2]
            if menuTable[menuRow][3] == true then
                printString = printString .. " (U)"
            end
            if menuTable[menuRow][4] == true then
                printString = printString .. " (B)"
            end
            print(printString)
        end
        --print the indicator arrow
        term.setCursorPos(1, currentSelection+firstItemRow-1)
        print(">")

        --Receive and process keyboard input
        sleep(0.2)
        local eventtype, key = os.pullEvent()  --get keyboard input
        if key == keys.up then --up key
            currentSelection = LoopVariable(currentSelection, menuLength, "-")
        elseif key == keys.down then --down key
            currentSelection = LoopVariable(currentSelection, menuLength, "+")
        elseif key == keys.a then --add a new item. 'a' key
            menuTable[menuLength+1] = GetNewPaste()
            menuLength = menuLength + 1
        elseif key == keys.r then --remove the currently selected item. 'r' key
            for i = currentSelection,menuLength-1 do
                menuTable[i] = menuTable[i+1]
            end
            menuTable[menuLength] = nil
            menuLength = menuLength - 1
        elseif key == keys.u then --toggle update
            menuTable[currentSelection][3] = not menuTable[currentSelection][3]
        elseif key == keys.b then --toggle run on boot
            menuTable[currentSelection][4] = not menuTable[currentSelection][4]
        elseif key == keys.m then
            local tempRow = menuTable[currentSelection]
            for i = currentSelection,menuLength-1 do
                menuTable[i] = menuTable[i+1]
            end
            menuTable[menuLength] = tempRow
        elseif key == keys.h then
            HelpScreen()
        end
    until key == keys.enter

    --return result
    term.clear()
    print("Saving settings...") sleep(2)
    return menuTable
end

function SaveCSV(dataTable, fileName) --saves a table as a CSV
    --this routine will create/overwrite a text document and save the link and program name
    local saveFile = fs.open(fileName,"w")
    --iterate through each row of the table
    for tableRow = 1, #dataTable do
        local line = ""
        --iterate through each column of a row
        for tableCol = 1, #dataTable[tableRow] do
            line = line .. tostring(dataTable[tableRow][tableCol]) .. ","
        end
        saveFile.writeLine(line)
    end
    saveFile.close()
end

function LoadCSV(fileName) --loads a CSV and returns it as a table
    print("Loading data from existing file..")
    local file = fs.open(fileName,"r") --open the file
    local lineString = file.readLine() --read the first line from the file
    local dataMatrix = {} --create a matrix to store the values in
    local lineNumber = 0

    while lineString ~= null do --until the line is empty
        lineNumber = lineNumber + 1
        dataMatrix[lineNumber] = {} --declare a new row in the matrix
        local startChar = 1 --initialize start position for the string scan
        local endChar   = string.find(lineString,",",startChar)  --initialize end position for the scan
        while endChar ~= nil do
            dataMatrix[lineNumber][#dataMatrix[lineNumber]+1] = ToBoolean(string.sub(lineString,startChar,endChar-1))
            startChar = endChar + 1
            endChar = string.find(lineString,",",startChar) --look in the string for "," starting from X
        end
        lineString = file.readLine() --read the next line
    end

    file:close()
    return dataMatrix
end

function UpdateProgram(pasteLink, programName) --updates a program from pastebin if possile
    print("\n>Updating " .. programName) --display message
    shell.run("rename", programName, "Old" .. programName) --rename old program
    if shell.run("pastebin", "get", pasteLink, programName) then --attempt to download a new version
        shell.run("delete", "Old" .. programName) --if success, delete the old program
    else
        shell.run("rename", "Old" .. programName, programName) --if fail, restore old version
        print("Failed to update. Old version kept.") --print error message
    end
    sleep(1)
end

function HelpScreen() --shows a guide for program use.
    term.clear() term.setCursorPos(1,1)
    print("HELP 1 of 2")
    print("1. Navigate the menu unsing UP and DOWN keys.")
    print("2. Use 'A' to add a program to the end of the list.")
    print("3. Use 'R' to remove a program from the list.")
    print("4. Toggle 'Update file' with 'U'. Programs tagged with (U) will be updated from Pastebin on boot.")
    read()
    term.clear() term.setCursorPos(1,1)
    print("HELP 2 of 2")
    print("5. Toggle 'Run on boot' with 'B'. Programs tagged with (B) will be run on boot.")
    print("6. Use 'M' to move a program to the end of the list.")
    print("Note: Updating and Running is done sequentially, top to bottom.")
    print("Hit 'enter' to return to the menu.")
    read()
end

function RunProgram(programName) --runs a program in a shell if possible
    print("\n>Running " .. programName) --display message
    if not shell.run(programName) then --run program. if unsuccessful...
        print("Could not run " .. programName)
        sleep(1)
    end
end

function GetNewPaste() --gets a new paste. LINK, NAME, FALSE, FALSE
    term.clear() term.setCursorPos(1,1)
    local link, progName
    --get paste link
    repeat
        print("- Add a new program to the list.")
        print("Enter the paste ID of the program you wish to add.\nMust be 8 characters long.")
        print("")
        link = tostring(read())
        term.clear() term.setCursorPos(1,1)
        if string.len(link) ~= 8 then
            print("Link is wrong length. " .. string.len(link))
        end
    until string.len(link) == 8
    term.clear() term.setCursorPos(1,1)

    --get program name
    repeat
        print("- Add a new program to the list.")
        print("Enter program name. Must be over 3 characters")
        print("")
        progName = tostring(read())
        term.clear() term.setCursorPos(1,1)
        if string.len(progName) <= 3 then
            print("Name is wrong length. " .. string.len(progName))
        end
    until string.len(progName) > 3
    term.clear() term.setCursorPos(1,1)

    --return the link, name, do not update, do not run on boot
    shell.run("pastebin", "get", link, progName)
    return {link, progName, false, false}
end

function ToBoolean(text) --converts a string to it's boolean if 'true' or 'false'
    if string.lower(text) == "true" then return true end
    if string.lower(text) == "false" then return false end
    return text
end

function LoopVariable(i, maximum, direction) --loops variable from 1->maximum->1
    if direction == "+" and i >= maximum    then return 1       end
    if direction == "+" and i  < maximum    then return i+1     end
    if direction == "-" and i <= 1          then return maximum end
    if direction == "-" and i  > 1          then return i-1     end
end

function CountdownBoolPrompt(text, promptDuration) --prints text and counts down waiting for Y/N
    for timeLeft = promptDuration,0,-1 do --for the numer of seconds specified...
        os.startTimer(1) --start a 1s timer
        term.clear() term.setCursorPos(1,1)
        print(text.."\n(Y/N) Program will continue in "..timeLeft.."s") --print a prompt
        local event, result = os.pullEvent() --detect key press for processing below
        if result == keys.enter or result == keys.y then return true
        elseif result == keys.n then return false
        end
    end
    return false
end

term.clear() term.setCursorPos(1,1)
Main()