OC-DOS installer

-- Licensed under the MIT License

-- Copyright (c) 2020 Ocawesome101

-- Permission is hereby granted, free of charge, to any person obtaining a copy
-- of this software and associated documentation files (the "Software"), to deal
-- in the Software without restriction, including without limitation the rights
-- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-- copies of the Software, and to permit persons to whom the Software is
-- furnished to do so, subject to the following conditions:

-- The above copyright notice and this permission notice shall be included in all
-- copies or substantial portions of the Software.

-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-- SOFTWARE.

local args = {...}

-- Set these to the proper name and repo containing your files and a files.list
local USER = "ocawesome101"
local REPO = "oc-dos"
local BRANCH = "master"

local term = term or require("term")
local read = read or io.read
local http = internet or require("component").internet
local fs = fs or require("filesystem")

local write = write or term.write

local path = args[1] or nil

local function install(path)
  local url = "https://raw.githubusercontent.com/" .. USER .. "/" .. REPO .. "/" .. branch .. "/files.list"
  local function download(URL)
    local h
    if http.request then
      h = http.request(URL)
      h.finishConnect()
    else
      h = http.get(URL)
    end
    return h
  end
  local handle = download(url)
  local data = ""
  repeat
    local chunk = handle.read(0xFFFF)
    data = data .. (chunk or "")
  until not chunk

  handle:close()

  local lines = {}
  local word = ""
  -- Split the files list into lines
  for char in string.gmatch(data, ".") do
    if char == "\n" then
      table.insert(lines, word)
      word = ""
    else
      word = word .. char
    end
  end
  -- Finally, download the files
  local baseURL = "https://raw.githubusercontent.com/" .. USER .. "/" .. REPO .. "/" .. BRANCH .. "/"
  for i=1, #lines, 1 do
    if lines[i]:sub(-1) == "/" then
      print("Creating " .. path .. "/" .. lines[i])
      fs.makeDirectory(path .. lines[i])
    else
      print("Downloading " .. lines[i])
      local handle = download(baseURL .. lines[i])
      local data = ""
      repeat
        local chunk = handle.read(0xFFFF)
        data = data .. (chunk or "")
      until not chunk

      handle:close()

      print("Writing " .. lines[i])
      local handle = fs.open(path .. "/" .. lines[i], "w")
      if fs.proxy then
        handle:write(data)
        handle:close()
      else
        handle.write(data)
        handle.close()
      end
    end
  end
  fs.setLabel(path, "Open Kernel")
end

local mounts = fs.list("/mnt")
local choice
while true do
  print("Please select an install medium.")
  if type(mounts) == "function" then
    local m = {}
    for mount in mounts do
      print(i, "/mnt/" .. mount)
      table.insert(m, mount)
    end
    mounts = m
  else
    for i=1, #mounts, 1 do
      print(i, "/mnt/" .. mounts[i])
    end
  end

  write("> ")

  local input = read()
  if not mounts[tonumber(input)] then
    print("Invalid selection")
  else
    choice = tonumber(input)
    break
  end
end

local selection = path or "/mnt/" .. mounts[choice]

print("You have selected " .. selection .. ". Continue?")
write("[y/N]: ")

local input = read()

if input:lower() ~= "y" then
  print("Answer was not yes, assuming no. Have a good day.")
  return false
end

install(selection)