ComputerCraft GitHub Downloader

local async = true
local silent = false

local preset = {
    user = nil,
    repo = nil,
    branch = nil,
    path = nil,
    start = function()
        if not silent then print("Pobieranie danych z GitHub...") end
    end,
    done = function()
        if not silent then print("Gotowe") end
    end
}

local args = {...}

args[1] = preset.user or args[1]
args[2] = preset.repo or args[2]
args[3] = preset.branch or args[3] or "master"
args[4] = preset.path or args[4] or ""

if #args < 2 then
        print("Uzycie:\n"..((shell and shell.getRunningProgram()) or "git").." <uzytkownik> <repozytorium>") error()
end

local function save(data,file)
    local file = shell.resolve(file:gsub("%%20"," "))
    if not (fs.exists(string.sub(file,1,#file - #fs.getName(file))) and fs.isDir(string.sub(file,1,#file - #fs.getName(file)))) then
        if fs.exists(string.sub(file,1,#file - #fs.getName(file))) then fs.delete(string.sub(file,1,#file - #fs.getName(file))) end
        fs.makeDir(string.sub(file,1,#file - #fs.getName(file)))
    end
    local f = fs.open(file,"w")
    f.write(data)
    f.close()
end

local function download(url, file)
    save(http.get(url).readAll(),file)
end

if not json then
    download("http://pastebin.com/raw.php?i=4nRg9CHU","json")
    os.loadAPI("json")
end

preset.start()
local data = json.decode(http.get("https://api.github.com/repos/"..args[1].."/"..args[2].."/git/trees/"..args[3].."?recursive=1").readAll())
if data.message and data.message:find("Polaczenie z API nie powiodlo sie.") then error("Blad w API, sprobuj pozniej.") end
if data.message and data.message == "Not found" then error("Niepoprawne repozytorium",2) else
    for k,v in pairs(data.tree) do
        -- Make directories
        if v.type == "tree" then
            fs.makeDir(fs.combine(args[4],v.path))
            if not hide_progress then
            end
        end
    end
    local drawProgress
    if async and not silent then
        local _, y = term.getCursorPos()
        local wide, _ = term.getSize()
        term.setCursorPos(1, y)
        term.write("[")
        term.setCursorPos(wide - 6, y)
        term.write("]")
        drawProgress = function(done, max)
            local value = done / max
            term.setCursorPos(2,y)
            term.write(("="):rep(math.floor(value * (wide - 8))))
            local percent = math.floor(value * 100) .. "%"
            term.setCursorPos(wide - percent:len(),y)
            term.write(percent)
        end
    end
    local filecount = 0
    local downloaded = 0
    local paths = {}
    local failed = {}
    for k,v in pairs(data.tree) do
        -- Send all HTTP requests (async)
        if v.type == "blob" then
            v.path = v.path:gsub("%s","%%20")
            local url = "https://raw.github.com/"..args[1].."/"..args[2].."/"..args[3].."/"..v.path,fs.combine(args[4],v.path)
            if async then
                http.request(url)
                paths[url] = fs.combine(args[4],v.path)
                filecount = filecount + 1
            else
                download(url, fs.combine(args[4], v.path))
                if not silent then print(fs.combine(args[4], v.path)) end
            end
        end
    end
    while downloaded < filecount do
        local e, a, b = os.pullEvent()
        if e == "http_success" then
            save(b.readAll(),paths[a])
            downloaded = downloaded + 1
            if not silent then drawProgress(downloaded,filecount) end
        elseif e == "http_failure" then
            -- Retry in 3 seconds
            failed[os.startTimer(3)] = a
        elseif e == "timer" and failed[a] then
            http.request(failed[a])
        end
    end
end
preset.done()
shell.run("delete README*.*")
shell.run("delete json*")