advancedLoader Installer

-- The following copyright notice applies to this file and the bootcode itself.
--[[
Copyright 2018 Luca_S

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 bootCode = [[local drives = {}
local filesystems = {}
local invoke = component.invoke

local function formatMemory(mem)
    local units = {"B", "KiB", "MiB", "GiB"}
    local unit = 1
    while mem > 1024 and units[unit] do
        unit = unit + 1
        mem = mem/1024
    end
    return mem.." "..units[unit]
end

local function getBootCode(addr)
    local sector1 = invoke(addr, "readSector", 1)
    for i = 1,#sector1 do
        if sector1:sub(i,i)=="\0" then
            sector1 = sector1:sub(1,i-1)
            break
        end
    end
    return sector1
end

local eeprom = component.list("eeprom")()

computer.getBootAddress = function()
    return invoke(eeprom, "getData")
end

computer.setBootAddress = function(addr)
    return invoke(eeprom, "setData", addr)
end

local function isBootable(addr)
    if component.type(addr) == "drive" then
        local f, err = load(getBootCode(addr))
        if not f then
            return false
        end
        return true
    elseif component.type(addr) == "filesystem" then
        return invoke(addr, "exists", "init.lua") and not invoke(addr, "isDirectory", "init.lua")
    else
        return false
    end
end

for i, _ in pairs(component.list("drive")) do
    if isBootable(i) then
        drives[#drives+1] = i
    end
end

for i, _ in pairs(component.list("filesystem")) do
    if isBootable(i) then
        filesystems[#filesystems+1] = i
    end
end

local screen = component.list("screen")()
local gpu = component.list("gpu")()
invoke(gpu, "bind", screen)
invoke(gpu, "setResolution", invoke(gpu, "maxResolution"))
local w, h = invoke(gpu, "getResolution")
local function clear()
    invoke(gpu, "setForeground", 0xFFFFFF)
    invoke(gpu, "setBackground", 0x000000)
    invoke(gpu, "fill", 1, 1, w, h, " ")
end
clear()

local function center(text, y)
    local x = w/2-#text/2
    invoke(gpu, "set", x, y, text)
end

local bootable = {}
for _, v in pairs(drives) do
    bootable[#bootable+1] = v
end
for _, v in pairs(filesystems) do
    bootable[#bootable+1] = v
end

local bootAddress = computer.getBootAddress()

for i, v in pairs(bootable) do
    if v == bootAddress then
        selected = i
        break
    end
end

local function drawMenu()
    center("Advanced Bootloader", 2)
    center("Select boot medium", 3)
    center("Computer Memory: "..formatMemory(computer.totalMemory()), 4)

    for i, v in pairs(bootable) do
        if i == selected then
            invoke(gpu, "setForeground", 0x000000)
            invoke(gpu, "setBackground", 0xFFFFFF)
        end

        invoke(gpu, "fill", 1, i+5, w, 1, " ") -- Clear line
        center(v .. "(" .. (invoke(v, "getLabel") or "No Label") .. ")", i+5)

        if i == selected then
            invoke(gpu, "setForeground", 0xFFFFFF)
            invoke(gpu, "setBackground", 0x000000)
        end
    end
end

local function boot(addr)
    clear()
    center("Booting " .. addr .. "(" .. (invoke(addr, "getLabel") or "No Label") .. ")", math.floor(h/2))
    center("Please wait...", math.floor(h/2)+1)
    computer.setBootAddress(addr)
    if component.type(addr) == "filesystem" then
        local handle, err = invoke(addr, "open", "/init.lua")
        if not handle then
            error(err)
        end
        local bootCode = ""
        repeat
            local chunk = invoke(addr, "read", handle, math.huge)
            bootCode = bootCode..(chunk or "")
        until not chunk
        load(bootCode)()
    elseif component.type(addr) == "drive" then
        load(getBootCode(addr))()
    end
    clear()
end

if #bootable == 1 then
    boot(bootable[1])
elseif #bootable == 0 then
    error("No bootable device!")
end

-- Down arrow: 208
-- Up arrow: 200
-- Enter: 28

drawMenu()

while true do
    local e, _, _, code = computer.pullSignal()
    if e == "key_down" then
        if code == 208 then
            selected = selected + 1
            if selected > #bootable then
                selected = 1
            end
        elseif code == 200 then
            selected = selected - 1
            if selected < 1 then
                selected = #bootable
            end
        elseif code == 28 then
            boot(bootable[selected])
        end
        drawMenu()
    elseif e == "touch" then
        -- Code is the Y coordinate of the touch
        if bootable[code-5] then
            if selected == code - 5 then
                boot(bootable[selected])
            else
                selected = code - 5
            end
        end
        drawMenu()
    end
end]]
io.write("Do you want to install advancedLoader to the currently inserted EEPROM? [y/N]")
if io.read():lower() ~= "y" then
    print("Aborted!")
    return
end
local c = require("component")
print("Flashing EEPROM, do NOT power down your computer!")
c.eeprom.set(bootCode)
c.eeprom.setLabel("advancedLoader")
print("Completed! :)")