local AWEFS_version = "01"

local drive = component.list("drive", true)()
local eeprom = component.list("eeprom")()
component.invoke(eeprom, "setData", drive)
drive = component.proxy(drive)


local function readBytes(driveProxy,offset, count)
    local buffer = ""
    for i = 1, count do
        local byte = math.abs(driveProxy.readByte(offset))
        buffer = buffer .. utf8.char(byte)
        offset = offset + 1
    end
    return buffer
end

local function tryLoad(driveProxy)
    local signature = readBytes(driveProxy,1,8)
    if signature ~= "AWEFS   " then
        return false, nil, "mismatched signature"
    end
    local version = readBytes(driveProxy,9,2)
    if version ~= AWEFS_version then
        return false, nil, "mismatched version"
    end

    local bootSec = readBytes(driveProxy,65,959)
    local sn = readBytes(driveProxy,11,8)

    bootSec = bootSec:gsub("%\0","")

    local init, err = load(
        bootSec, string.format("=%s",sn), "bt", _G)

    return true,init,err,sn
end

local success,init,err, sn = tryLoad(drive)

if not success then
    error(err)
end

if not init then
    error("no bootable medium found :( " .. err)
end

return init(drive.address,sn,drive,readBytes)