--:Minify:--
-- Usage:
--   losetup <path>          attach directory or .hfs image; print loop id
--   losetup -d <id>         detach loop device
--   losetup -l              list attached loop devices
--   losetup -i <path>       force image mode (even without .hfs extension)
--   losetup --help

local name = syscall.getTask(syscall.getpid()).name
local args, opts = {}, { d=false, l=false, i=false, help=false }

for _, v in ipairs({...}) do
    if v:sub(1,2) == "--" then
        local o = v:sub(3)
        if o == "help" then opts.help = true
        else print(name..": unrecognised option '"..v.."'")
             print("try '"..name.." --help' for more information.")
             syscall.exit(1); return end
    elseif v:sub(1,1) == "-" then
        for i = 2, #v do
            local c = v:sub(i,i)
            if opts[c] ~= nil then opts[c] = true
            else print(name..": invalid option '-"..c.."'")
                 print("try '"..name.." --help' for more information.")
                 syscall.exit(1); return end
        end
    else
        table.insert(args, v)
    end
end

if opts.help then
    print("Usage: "..name.." <path>")
    print("       "..name.." -i <path>")
    print("       "..name.." -d <id>")
    print("       "..name.." -l")
    print("")
    print("Manage loop devices.")
    print("")
    print("  <path>      attach a directory (bind) or .hfs image file")
    print("  -i <path>   force image mode for the given file")
    print("  -d <id>     detach loop device by id (must be unmounted first)")
    print("  -l          list all currently attached loop devices")
    print("")
    print("Requires root. Loop device ids look like loop0, loop1, …")
    return
end

if opts.l then
    local ok, devs = pcall(syscall.lolist)
    if not ok then
        print(name..": "..tostring(devs)); syscall.exit(1); return
    end
    local any = false
    local ids = {}
    for id in pairs(devs) do ids[#ids+1] = id end
    table.sort(ids)
    for _, id in ipairs(ids) do
        any = true
        local info   = devs[id]
        local mode   = (type(info) == "table" and info.mode) or "bind"
        local path   = (type(info) == "table" and info.path) or tostring(info)
        local colour = mode == "image" and 5 or 4
        syscall.devctl(1, "sfgc", 3)
        printInline(string.format("%-10s", id))
        syscall.devctl(1, "sfgc", colour)
        printInline(string.format("%-7s", "["..mode.."]"))
        syscall.devctl(1, "sfgc", 1)
        print(" "..path)
    end
    if not any then
        syscall.devctl(1, "sfgc", 14)
        print(name..": no loop devices attached")
        syscall.devctl(1, "sfgc", 1)
    end
    return
end

if opts.d then
    if #args < 1 then
        print(name..": -d requires a loop device id")
        print("try '"..name.." --help' for more information.")
        syscall.exit(1); return
    end
    local id = args[1]
    local ok, err = pcall(syscall.lodetach, id)
    if not ok then
        local msg = tostring(err)
        if     msg:find("EPERM")  then msg = "Permission denied"
        elseif msg:find("ENXIO")  then msg = "no such loop device '"..id.."'"
        elseif msg:find("EBUSY")  then msg = "device '"..id.."' is still mounted, unmount first"
        end
        print(name..": "..msg); syscall.exit(1); return
    end
    syscall.devctl(1, "sfgc", 10)
    print(name..": detached "..id)
    syscall.devctl(1, "sfgc", 1)
    return
end

if #args < 1 then
    print(name..": missing path operand")
    print("try '"..name.." --help' for more information.")
    syscall.exit(1); return
end

local path = args[1]
if path:sub(1,1) ~= "/" then
    path = syscall.getcwd().."/"..path
end

local ftype = syscall.type and syscall.type(path)
if not (ftype == "file" or ftype == "directory") then
    print(name..": '"..args[1].."': no such file or directory")
    syscall.exit(1); return
end

local ok, result = pcall(syscall.losetup, path, opts.i or nil)
if not ok then
    local msg = tostring(result)
    if     msg:find("EPERM")   then msg = "Permission denied"
    elseif msg:find("ENOENT")  then msg = "'"..args[1].."': no such file"
    elseif msg:find("EINVAL")  then msg = "'"..args[1].."': not a directory or .hfs image"
    elseif msg:find("EIO")     then msg = "'"..args[1].."': I/O error reading image"
    end
    print(name..": "..msg); syscall.exit(1); return
end

print(result)