--:Minify:--
-- Usage:
--   loimgcreate <srcdir> <image.hfs>    create image from directory
--   loimgcreate -x <image.hfs> <dest>   extract image back to a directory
--   loimgcreate --help

local name = syscall.getTask(syscall.getpid()).name
local args, opts = {}, { x=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.." <srcdir> <image.hfs>")
    print("       "..name.." -x <image.hfs> <destdir>")
    print("")
    print("Pack a directory into a portable HFS image file, or extract one.")
    print("")
    print("  <srcdir> <image.hfs>     recursively pack srcdir into image.hfs")
    print("  -x <image.hfs> <dest>    extract image.hfs into dest (created if needed)")
    print("")
    print("HFS images can be mounted with:")
    print("  mount -o loop /path/to/image.hfs /mnt/point")
    print("")
    print("Requires root.")
    return
end

local fs = require("fs")

if opts.x then
    if #args < 2 then
        print(name..": -x requires <image.hfs> and <destdir>")
        print("try '"..name.." --help' for more information.")
        syscall.exit(1); return
    end

    local imgPath  = args[1]
    local destPath = args[2]
    if imgPath:sub(1,1)  ~= "/" then imgPath  = syscall.getcwd().."/"..imgPath  end
    if destPath:sub(1,1) ~= "/" then destPath = syscall.getcwd().."/"..destPath end

    local tmpMnt = "/tmp/._loimgcreate_"..tostring(math.random(100000,999999))

    local ok1, loopId = pcall(syscall.losetup, imgPath, true)
    if not ok1 then
        print(name..": losetup: "..tostring(loopId)); syscall.exit(1); return
    end

    local ok2, merr = pcall(syscall.mount, tmpMnt, loopId)
    if not ok2 then
        pcall(syscall.lodetach, loopId)
        print(name..": mount: "..tostring(merr)); syscall.exit(1); return
    end

    if not fs.isDir(destPath) then
        local ok3, derr = pcall(syscall.mkdir, destPath)
        if not ok3 then
            pcall(syscall.umount, tmpMnt); pcall(syscall.lodetach, loopId)
            print(name..": mkdir '"..args[2].."': "..tostring(derr))
            syscall.exit(1); return
        end
    end

    local count = 0
    local function copyTree(src, dst)
        local entries = fs.list(src)
        if not entries then return end
        for _, ent in ipairs(entries) do
            local srcFull = src:gsub("/$","").."/"..ent
            local dstFull = dst:gsub("/$","").."/"..ent
            if fs.isDir(srcFull) then
                pcall(syscall.mkdir, dstFull)
                copyTree(srcFull, dstFull)
            else
                local ok, rfd = pcall(syscall.open, srcFull, "r")
                if ok then
                    local ok2, wfd = pcall(syscall.open, dstFull, "w")
                    if ok2 then
                        local ok3, data = pcall(syscall.read, rfd, 65536*16)
                        if ok3 and data then pcall(syscall.write, wfd, data) end
                        pcall(syscall.close, wfd)
                        count = count + 1
                    end
                    pcall(syscall.close, rfd)
                end
            end
        end
    end

    copyTree(tmpMnt, destPath)

    pcall(syscall.umount, tmpMnt)
    pcall(syscall.lodetach, loopId)

    syscall.devctl(1, "sfgc", 10)
    print(name..": extracted "..count.." file(s) to "..destPath)
    syscall.devctl(1, "sfgc", 1)
    return
end

if #args < 2 then
    print(name..": missing operands — need <srcdir> and <image.hfs>")
    print("try '"..name.." --help' for more information.")
    syscall.exit(1); return
end

local srcPath  = args[1]
local imgPath  = args[2]
if srcPath:sub(1,1) ~= "/" then srcPath = syscall.getcwd().."/"..srcPath end
if imgPath:sub(1,1) ~= "/" then imgPath = syscall.getcwd().."/"..imgPath end

if not fs.isDir(srcPath) then
    print(name..": '"..args[1].."': not a directory")
    syscall.exit(1); return
end

local ok, imgStr = pcall(syscall.loimgcreate, srcPath)
if not ok then
    local msg = tostring(imgStr)
    if msg:find("EPERM") then msg = "Permission denied"
    elseif msg:find("ENOTDIR") then msg = "'"..args[1].."': not a directory" end
    print(name..": "..msg); syscall.exit(1); return
end

local ok2, werr = pcall(syscall.loimgwrite, imgStr, imgPath)
if not ok2 then
    print(name..": write '"..args[2].."': "..tostring(werr))
    syscall.exit(1); return
end

local lineCount = 0
for _ in imgStr:gmatch("\n") do lineCount = lineCount + 1 end
local byteCount = #imgStr

syscall.devctl(1, "sfgc", 10)
print(name..": image written to "..imgPath)
syscall.devctl(1, "sfgc", 14)
print(string.format("  %d records, %d bytes", lineCount - 1, byteCount))
syscall.devctl(1, "sfgc", 1)