Package

local commonFileData = [[

_G.NovaPackageData = _G.NovaPackageData or { } -- so packages aren't loaded multiple times

local packages = { }

local find
find = function( name, path )
    if _G.NovaPackageData[name] then
        return _G.NovaPackageData[name]
    end
    path = path or ""
    local files = fs.list( path )
    for i = 1,#files do
        if fs.isDir( path .. "/" .. files[ i ] ) then
            if path .. "/" .. files[ i ] ~= "/rom" then
                local p = find( name, path .. "/" .. files[ i ] )
                if p then
                    return p
                end
            end
        else
            local h = fs.open( path .. "/" .. files[ i ], "r" )
            if h then
                local content = h.readAll( )
                h.close( )
                if content:sub( 1, 25 ) == "-- Nova package(library)\n" then
                    if content:sub( 26, 28 + #name ) == "-- " .. name then
                        local f, err = loadstring( content, files[ i ] )
                        if f then
                            setfenv( f, getfenv( ) )
                            local ok, data = pcall( f )
                            if ok then
                                _G.NovaPackageData[name] = data
                                return data
                            else
                                error( data, 0 )
                            end
                        else
                            error( err, 0 )
                        end
                    end
                end
            end
        end
    end
end

for i = 1,#dependencies do
    local pack = find( dependencies[ i ] )
    if pack then
        packages[ dependencies[ i ] ] = pack
    else
        error( "requires \"" .. dependencies[ i ] .. "\" package", 0 )
    end
end

local package = { }
local env = { }
setmetatable( env, { __index = getfenv( ) } )
_G.NovaPackageData[name] = package

env.package = package
env.require = function( file )
    local pos = file:find( "%." )
    if pos then
        local pack = file:sub( 1, pos - 1 )
        if packages[ pack ] then
            return packages[ pack ].run( file:sub( pos + 1 ) )
        else
            error( "no such package \"" .. pack .. "\"", 0 )
        end
    else
        return package.run( file )
    end
end

function package.read( name )
    if files[ name:lower( ) ] then
        return files[ name:lower( ) ]
    end
    return false
end
function package.run( file, ... )
    local content = files[ file:lower( ) ]
    if content then
        local f, err = loadstring( content, file )
        if f then
            setfenv( f, env )
            local ok, data = pcall( f, ... )
            if ok then
                return data
            else
                error( data, 0 )
            end
        else
            error( err,0 )
        end
    else
        error( "could not read file", 0 )
    end
end
function package.getName( )
    return name
end
function package.getDependencies( ) -- clones the table so you can't change the local one:
    local t = { }
    for i = 1,#dependencies do
        t[ i ] = dependencies[ i ]
    end
    return t
end
]]

local runFileData = [[
return package.run( mainFile, ... )
]]

function create( name )
    if type( name ) ~= "string" then
        error( "string name expected, got " .. type( name ), 2 )
    end
    local p = { }
    p.name = name
    p.files = { }
    p.requires = { }
    function p:addFile( name, content )
        if type( name ) ~= "string" then
            error( "string name expected, got " .. type( name ), 2 )
        end
        if type( content ) ~= "string" then
            error( "string content (or path) expected [#2], got " .. type( content ), 2 )
        end
        if fs.exists( content ) and not fs.isDir( content ) then
            local h = fs.open( content, "r" )
            if h then
                content = h.readAll( )
                h.close( )
            else
                error( "could not read file", 0 )
            end
        end
        self.files[name:lower( )] = content
    end
    function p:addDependency( pack )
        if type( pack ) ~= "string" then
            error( "string pack expected, got " .. type( pack ), 2 )
        end
        self.requires[ #self.requires + 1 ] = pack
    end
    function p:save( path )
        if type( path ) ~= "string" then
            error( "string path expected, got " .. type( path ), 2 )
        end
        local content = "-- Nova package(library)\n-- " .. self.name .. "\n"
        content = content .. "local name = " .. string.format( "%q", self.name ) .. "\n"
        content = content .. "local files = " .. textutils.serialize( self.files ) .. "\n"
        content = content .. "local dependencies = " .. textutils.serialize( self.requires ) .. "\n"
        content = content .. commonFileData
        content = content .. "return package\n"
        local h = fs.open( path, "w" )
        if h then
            h.write( content )
            h.close( )
        else
            error( "could not write to file", 0 )
        end
    end
    function p:saveExecutable( path, mainFile )
        if type( path ) ~= "string" then
            error( "string path expected, got " .. type( path ), 2 )
        end
        if type( mainFile ) ~= "string" then
            error( "string main file expected [#2], got " .. type( mainFile ), 2 )
        end
        local content = "-- Nova package(library)\n"
        content = content .. "local mainFile = " .. string.format( "%q", mainFile ) .. "\n"
        content = content .. "local name = " .. string.format( "%q", self.name ) .. "\n"
        content = content .. "local files = " .. textutils.serialize( self.files ) .. "\n"
        content = content .. "local dependencies = " .. textutils.serialize( self.requires ) .. "\n"
        content = content .. commonFileData
        content = content .. runFileData
        local h = fs.open( path, "w" )
        if h then
            h.write( content )
            h.close( )
        else
            error( "could not write to file", 0 )
        end
    end
    return p
end

function load( path )
    if type( path ) ~= "string" then
        error( "string path expected, got " .. type( path ), 2 )
    end
    local f, err = loadfile( path )
    if f then
        setfenv( f, getfenv( ) )
        local ok, data = pcall( f )
        if ok then
            return data
        else
            error( data, 0 )
        end
    else
        error( err, 0 )
    end
end

local f
f = function( name, path )
    if _G.NovaPackageData[name] then
        return _G.NovaPackageData[name]
    end
    path = path or ""
    local files = fs.list( path )
    for i = 1,#files do
        if fs.isDir( path .. "/" .. files[ i ] ) then
            if path .. "/" .. files[ i ] ~= "/rom" then
                local p = f( name, path .. "/" .. files[ i ] )
                if p then
                    return p
                end
            end
        else
            local h = fs.open( path .. "/" .. files[ i ], "r" )
            if h then
                local content = h.readAll( )
                h.close( )
                if content:sub( 1, 25 ) == "-- Nova package(library)\n" then
                    if content:sub( 26, 28 + #name ) == "-- " .. name then
                        return path .. "/" .. files[i]
                    end
                end
            end
        end
    end
end

function find( name )
    return f( name )
end