crane

--[[
License for the LZW compression:
MIT License
Copyright (c) 2016 Rochet2
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 util_raw = [[
local function canonicalize(path)
    return fs.combine(path, "")
end

local function segments(path)
    if canonicalize(path) == "" then return {} end
    local segs, rest = {}, path
    repeat
        table.insert(segs, 1, fs.getName(rest))
        rest = fs.getDir(rest)
    until rest == ""
    return segs
end

local function slice(tab, start, end_)
    return {table.unpack(tab, start, end_)}
end

local function compact_serialize(x)
    local t = type(x)
    if t == "number" then
        return tostring(x)
    elseif t == "string" then
        return textutils.serialise(x)
    elseif t == "table" then
        local out = "{"
        for k, v in pairs(x) do
            out = out .. string.format("[%s]=%s,", compact_serialize(k), compact_serialize(v))
        end
        return out .. "}"
    elseif t == "boolean" then
        return tostring(x)
    else
        error("Unsupported type " .. t)
    end
end

local function drop_last(t)
    local clone = slice(t)
    local length = #clone
    local v = clone[length]
    clone[length] = nil
    return clone, v
end
]]

local util = loadstring(util_raw .. "\nreturn {segments = segments, slice = slice, drop_last = drop_last, compact_serialize = compact_serialize}")()

local runtime = util_raw .. [[
local savepath = ".crane-persistent/" .. fname

-- Simple string operations
local function starts_with(s, with)
    return string.sub(s, 1, #with) == with
end
local function ends_with(s, with)
    return string.sub(s, -#with, -1) == with
end
local function contains(s, subs)
    return string.find(s, subs) ~= nil
end

local function copy_some_keys(keys)
    return function(from)
        local new = {}
        for _, key_to_copy in pairs(keys) do
            local x = from[key_to_copy]
            if type(x) == "table" then
                x = copy(x)
            end
            new[key_to_copy] = x
        end
        return new
    end
end

local function find_path(image, path)
    local focus = image
    local path = path
    if type(path) == "string" then path = segments(path) end
    for _, seg in pairs(path) do
        if type(focus) ~= "table" then error("Path segment " .. seg .. " is nonexistent or not a directory; full path " .. compact_serialize(path)) end
        focus = focus[seg]
    end
    return focus
end

local function get_parent(image, path)
    local init, last = drop_last(segments(path))
    local parent = find_path(image, init) or image
    return parent, last
end

-- magic from http://lua-users.org/wiki/SplitJoin
-- split string into lines
local function lines(str)
    local t = {}
    local function helper(line)
        table.insert(t, line)
        return ""
    end
    helper((str:gsub("(.-)\r?\n", helper)))
    return t
end

local function make_read_handle(text, binary)
    local lines = lines(text)
    local h = {}
    local line = 0
    function h.close() end
    if not binary then
        function h.readLine() line = line + 1 return lines[line] end
        function h.readAll() return text end
    else
        local remaining = text
        function h.read()
            local by = string.byte(remaining:sub(1, 1))
            remaining = remaining:sub(2)
            return by
        end
    end
    return h
end

local function make_write_handle(writefn, binary)
    local h = {}
    function h.close() end
    function h.flush() end
    if not binary then
        function h.write(t) return writefn(t) end
        function h.writeLine(t) return writefn(t .. "\n") end
    else
        function h.write(b) return writefn(string.char(b)) end
    end
    return h
end

local function mount_image(i)
    local options = i.options
    local image = i.tree

    local filesystem = copy_some_keys {"getName", "combine", "getDir"} (_G.fs)

    function filesystem.getFreeSpace()
        return math.huge -- well, it's in-memory...
    end

    function filesystem.exists(path)
        return find_path(image, path) ~= nil
    end

    function filesystem.isDir(path)
        return type(find_path(image, path)) == "table"
    end

    function filesystem.makeDir(path)
        local p, n = get_parent(image, path)
        p[n] = {}
    end

    function filesystem.delete(path)
        local p, n = get_parent(image, path)
        p[n] = nil
    end

    function filesystem.copy(from, to)
        local pf, nf = get_parent(image, from)
        local contents = pf[nf]
        local pt, nt = get_parent(image, to)
        pt[nt] = contents
    end

    function filesystem.move(from, to)
        filesystem.copy(from, to)
        local pf, nf = get_parent(image, from)
        pf[nf] = nil
    end

    function filesystem.contents(path)
        return find_path(image, path)
    end

    function filesystem.list(path)
        local out = {}
        local dir = find_path(image, path)
        for k, v in pairs(dir) do table.insert(out, k) end
        return out
    end

    function filesystem.open(path, mode)
        local parent, childname = get_parent(image, path)
        local node = parent[childname]
        local is_binary = ends_with(mode, "b")
        if starts_with(mode, "r") then
            if type(node) ~= "string" then error(path .. ": not a file!") end
            return make_read_handle(node, is_binary)
        elseif starts_with(mode, "a") or starts_with(mode, "w") then
            local function writer(str)
                parent[childname] = parent[childname] .. str
                if options.save_on_change then filesystem.save() end
            end
            if not starts_with(mode, "a") or node == nil then parent[childname] = "" end
            return make_write_handle(writer, is_binary)
        end
    end

    function filesystem.find(wildcard)
        -- Taken from Harbor: https://github.com/hugeblank/harbor/blob/master/harbor.lua
        -- Body donated to harbor by gollark, from PotatOS, and apparently indirectly from cclite:
        -- From here: https://github.com/Sorroko/cclite/blob/62677542ed63bd4db212f83da1357cb953e82ce3/src/emulator/native_api.lua
        local function recurse_spec(results, path, spec)
            local segment = spec:match('([^/]*)'):gsub('/', '')
            local pattern = '^' .. segment:gsub('[*]', '.+'):gsub('?', '.') .. '$'

            if filesystem.isDir(path) then
                for _, file in ipairs(filesystem.list(path)) do
                    if file:match(pattern) then
                        local f = filesystem.combine(path, file)

                        if filesystem.isDir(f) then
                            recurse_spec(results, f, spec:sub(#segment + 2))
                        end
                        if spec == segment then
                            table.insert(results, f)
                        end
                    end
                end
            end
        end
        local results = {}
        recurse_spec(results, '', wildcard)
        return results
    end

    function filesystem.getDrive()
        return "crane-vfs-" .. fname
    end

    function filesystem.isReadOnly(path)
        return false
    end

    local fo = fs.open
    function filesystem.save()
        local f = fo(savepath, "w")
        f.write(compact_serialize(i))
        f.close()
    end

    return filesystem
end

local function deepmerge(t1, t2)
    local out = {}
    for k, v in pairs(t1) do
        local onother = t2[k]
        if type(v) == "table" and type(onother) == "table" then
            out[k] = deepmerge(v, onother)
        else
            out[k] = v
        end
    end
    for k, v in pairs(t2) do
        if not out[k] then
            out[k] = v
        end
    end
    return out
end

local cli_args = {...}

local f = fs.open("/rom/apis/io.lua", "r") -- bodge reloading IO library
local IO_API_code = f.readAll()
f.close()

local function load_API(code, env, name)
    local e = setmetatable({}, { __index = env })
    load(code, "@" .. name, "t", env)()
    env[name] = e
end

local function replacement_require(path)
    return dofile(path)
end

local function execute(image, filename)
    local image = image
    if fs.exists(savepath) then
        local f = fs.open(savepath, "r")
        image = deepmerge(image, textutils.unserialise(f.readAll()))
    end

    local f = mount_image(image)

    local env = setmetatable({ fs = f, rawfs = _G.fs, require = replacement_require,
        os = setmetatable({}, { __index = _ENV.os }), { __index = _ENV })
    load_API(IO_API_code, env, "io")
    local func, err = load(f.contents(filename), "@" .. filename, "t", env)
    if err then error(err)
    else
        env.os.reboot = function() func() end
        return func(unpack(cli_args))
    end
end
]]

-- LZW Compressor
local a=string.char;local type=type;local b=string.sub;local c=table.concat;local d={}local e={}for f=0,255 do local g,h=a(f),a(f,0)d[g]=h;e[h]=g end;local function i(j,k,l,m)if l>=256 then l,m=0,m+1;if m>=256 then k={}m=1 end end;k[j]=a(l,m)l=l+1;return k,l,m end;local function compress(n)if type(n)~="string"then return nil,"string expected, got "..type(n)end;local o=#n;if o<=1 then return"u"..n end;local k={}local l,m=0,1;local p={"c"}local q=1;local r=2;local s=""for f=1,o do local t=b(n,f,f)local u=s..t;if not(d[u]or k[u])then local v=d[s]or k[s]if not v then return nil,"algorithm error, could not fetch word"end;p[r]=v;q=q+#v;r=r+1;if o<=q then return"u"..n end;k,l,m=i(u,k,l,m)s=t else s=u end end;p[r]=d[s]or k[s]q=q+#p[r]r=r+1;if o<=q then return"u"..n end;return c(p)end

local wrapper = [[local function y(b)local c="-"local d="__#"..math.random(0,10000)local e="\0";return b:gsub(c,d):gsub(e,c):gsub(d,e)end;local z="decompression failure; please redownload or contact developer";local a=string.char;local type=type;local b=string.sub;local c=table.concat;local d={}local e={}for f=0,255 do local g,h=a(f),a(f,0)d[g]=h;e[h]=g end;local function i(j,k,l,m)if l>=256 then l,m=0,m+1;if m>=256 then k={}m=1 end end;k[j]=a(l,m)l=l+1;return k,l,m end;local function n(j,k,l,m)if l>=256 then l,m=0,m+1;if m>=256 then k={}m=1 end end;k[a(l,m)]=j;l=l+1;return k,l,m end;local function dec(o)if type(o)~="string"then return nil,z end;if#o<1 then return nil,z end;local p=b(o,1,1)if p=="u"then return b(o,2)elseif p~="c"then return nil,z end;o=b(o,2)local q=#o;if q<2 then return nil,z end;local k={}local l,m=0,1;local r={}local s=1;local t=b(o,1,2)r[s]=e[t]or k[t]s=s+1;for f=3,q,2 do local u=b(o,f,f+1)local v=e[t]or k[t]if not v then return nil,z end;local w=e[u]or k[u]if w then r[s]=w;s=s+1;k,l,m=n(v..b(w,1,1),k,l,m)else local x=v..b(v,1,1)r[s]=x;s=s+1;k,l,m=n(x,k,l,m)end;t=u end;return c(r)end;local o,e=dec(y(%s));if e then error(e) end;load(o,"@loader","t",_ENV)(...)]]

local function encode_nuls(txt)
    local replace = "\0"
    local temp_replacement = ("__#%d#__"):format(math.random(-131072, 131072))
    local replace_with = "-"
    return txt:gsub(replace, temp_replacement):gsub(replace_with, replace):gsub(temp_replacement, replace_with)
end

local function compress_code(c)
    local comp = encode_nuls(compress(c))
    local txt = string.format("%q", comp):gsub("\\(%d%d%d)([^0-9])", function(x, y) return string.format("\\%d%s", tonumber(x), y) end)
    local out = wrapper:format(txt)
    --print(loadstring(out)())
    return out
end

local function find_imports(code)
    local imports = {}

    for i in code:gmatch "%-%-| CRANE ADD [\"'](.-)[\"']" do
        table.insert(imports, i)
        print("Detected explicit import", i)
    end
    return imports
end

local function add(path, content, tree)
    local segs, last = util.drop_last(util.segments(path))
    local deepest = tree
    for k, seg in pairs(segs) do
        if not deepest[seg] then
            deepest[seg] = {}
        end
        deepest = deepest[seg]
    end
    deepest[last] = content
end

local function load_from_root(file, tree)
    print("Adding", file)
    if not fs.exists(file) then error(file .. " does not exist.") end
    if fs.isDir(file) then
        for _, f in pairs(fs.list(file)) do
            load_from_root(fs.combine(file, f), tree)
        end
        return
    end

    local f = fs.open(file, "r")
    local c = f.readAll()
    f.close()
    add(file, c, tree)
    local imports = find_imports(c)
    for _, i in pairs(imports) do
        load_from_root(i, tree)
    end
end

local args = {...}
if #args < 2 then
    error([[Usage:
crane [output] [bundle startup] [other files to bundle] ]])
end

local root = args[2]
local ftree = {}

for _, wildcard in pairs(util.slice(args, 2)) do
    for _, possibility in pairs(fs.find(wildcard)) do
        load_from_root(possibility, ftree)
    end
end


local function minify(code)
    local url = "https://osmarks.tk/luamin/"
    http.request(url, code)
    while true do
        local event, result_url, handle = os.pullEvent()
        if event == "http_success" then
            local text = handle.readAll()
            handle.close()
            return text
        elseif event == "http_failure" then
            local text = handle.readAll()
            handle.close()
            error(text)
        end
    end
end

ftree[root] = minify(ftree[root])
local serialized_tree = util.compact_serialize({
    tree = ftree,
    options = {
        save_on_change = true
    }
})

local function shortest(s1, s2)
    if #s1 < #s2 then return s1 else return s2 end
end

local output = minify(([[
local fname = %s
%s
local image = %s
return execute(image, fname)
]]):format(util.compact_serialize(root), runtime, serialized_tree))

local f = fs.open(args[1], "w")
f.write("--| CRANE BUNDLE v2\n" .. shortest(compress_code(output), output))
f.close()

print "Done!"