INTERFACE WWW; (* module, i.e. namespace *)

type URI = OBJECT;

type Text = ilu.CString;

type URIOracle = SINGLETON OBJECT METHODS
	intern(in literal: Text): URI RAISES URISyntax;
	join(in here: URI, there: Text) : URI RAISES URISyntax
	difference(in here, there: URI) : Text
	scheme(in u: URI): Text; (* @# Scheme object type? *)
	fragment(in u: URI): Text;
	END;

type URLOracle = SINGLETON OBJECT SUPERTYPES URIOracle METHODS
	contactInfo(in u: URI, OUT host, port, ???);
	END;

	(* local knowledge base; i.e. local view of global KB *)
type Universe = SINGLETON OBJECT methods
	find(in address: URI, inout create: BOOL): Anchor;
	END;

type Anchor = OBJECT METHODS (* Oracle? *)
	(* belief system: who said so? when? what credentials? *)
		bind(in interface: URI) : Resource
			(* RAISES ??? *)
	END;

type ByteSeq = SEQUENCE OF BYTE;
type ByteStream = ???;

type Entity = OBJECT METHODS
	header(): ByteSeq;
	body(out content: BytStream): BOOL;
	END;

type EntityOracle = OBJECT METHODS
	headerFields(in e: Entity): CARDINAL;
	nthHeader(e: Entity, in n: CARDINAL, out name: Text, out value: Text);
	firstHeaderNamed(e: Entity, in name: Text): Text;
	END;

	(* sorts of resources *)
type Resource = OBJECT; (* @# any common methods? *)

type Document = OBJECT SUPERTYPES Resource METHODS
	 get(): Entity RAISES Auth, Comm; (* everything raises these? *)
		(*@@ credentials, authenticity constraints (caching params) *)
		(* username, password *)
		(* if-modified-since *)
		(* max age *)
		(* ETag *)
		(* volume info *)
	}

type ConvertableDocument = OBJECT SUPERTYPES Resource METHODS
	get(preferences: EntityMetric, out variants: EntitySeq): Entity;
	END;

type EntityMetric = object methods
	costBenefit(in: Entity): REAL;
	END;
type EntitySeq = SEQUENCE OF Entity;

	(* example:
		Anchor * a = Universe.find("http:...", CREATE)
		Document *d = a.bind(Document)
		Entity *e = d.get()
	*)

type MutableDocument = OBJECT supertypes Document METHODS
	(* @# QI on this type might lock the resource? *)
	 put(content: Entity): Entity // what does PUT return?
		 RAISES Auth, Comm; // everything raises these?
	}

type Board = OBJECT supertypes Document METHODS
	post(content: Entity): Entity // what does POST return?
		RAISES Auth, COMM;
	}

	(* for mailto: URLs *)
type MailBox = OBJECT SUPERTYPES Resource METHODS
	post(content: Entity);
	END;

type MailServer = object supertypes Resource methods
	post(content: Entity, replyTo: MailBox);
	END;

type TerminalServer = object methods
	login() RAISES Auth, Comm;
	END;

(* Thesis: just as HTTP was based on
the shared under standing around SMTP,
NNTP, MIME, and the like, HTTP-NG
will be based on the shared understanding
aound CORBA, M3, python, Java, Larch,
and the like. ILU/WWW is the next
paradigm in network applications
development after berkeley sockets.

@@ phil's notions arout chat being an
editing API. Parser "edits" the doc,
ala LINCKS.

angel: HTTP-NG gateway/proxy.
workgroup angel: hyper-G/LINCKS database
server. (consistent policies, parallel
editing, etc.)

spinner dispatcher/ilu requester
(encrypted channel, ala SSL)

proxy routing: "no route to object",
forwarding, etc.

access standard links w/out fetching doc
(to get GPD, stylesheet, interface, etc.)

Persistent objects:
Bento as model for comining LINCKS/editing
API with caching? (generations, not time
stamps nor opaque versions). What about
pointer swizzling, ala Texas?

integreate anselm's jhttpd "Entity" interface
as "local name service".

IPR of pass-through, redirect services?
(pipe to altavista, replace icons)
(tracking ala Yahoo, other redirectors)

THINK HARD ABOUT SECURITY -- explicit
semantics of calls as sentences. Who
said it? when? what scope?

GSS API, ban logic.

Authorization database: e.g. larch theorems
(in general, proof, or at least KB
goal search, ala algernon.)

client to report broken links to refering
server? (even ask to fix them?)

python module dictionary as local name service:
use method procs as object methods.

ISL: "final" annotation, ala dylan,
java? (java static -> ISL singleton)
@@hmmm... maybe final/sealed are only
relevant to implementations.

java interfaces -> M3: procedure
arguments need arg <: T as well as arg : T!
(impl: call-by-name methods)

ISL interface for DNS. (URI scheme too)
(use standard forms/relational syntax?)
dns://www.foo.com?query=A. PUT for
writes.

relational isomorphism: PUT->update,
POST->inset, GET->select. ???->join?
isomorphism to Bento, SGML, LINCKS.
(context-free grammar in general?)
regexp grammar?

@@ MIB interface. SNMP


(**************************)
(* legacy mapping to http *)

INTERFACE TelnetTP

	TYPE Word = ilu.CString; (* no spaces *)
	TYPE Command = SEQUENCE OF Word;

	TYPE Status = ilu.CString;
	(* @@obj type w/ methods to grok
	XYZ bumbers *)

END;

INTERFACE HTTP
	imports TelnetTP, RFC822, Rd;

	TYPE Request = OBJECT
		SUPERTYPES RFC822.Header
		METHODS
		FUNCTIONAL command(): TelnetTP.Command;
		FUNCTIONAL body(): BodyOpt;
	END;

	TYPE Response = OBJECT
		SUPERTYPES RFC822.Header
		METHODS
		FUNCTIONAL status(): TelnetTP.Status;
		FUNCTIONAL body(): BodyOpt;
	END;

	TYPE BodyOpt = OPTIONAL Rd.T;
END;


INTERFACE RFC822;
	(* implementations:
		c-client library, MH, python lib *)

	TYPE Header = OBJECT METHODS
		FUNCTIONAL fields(): HeaderFields;
		find(name: Id, INOUT index: int):
			BOOL;
			(* e.g. for(i=0; h.find("to:", &i);) *)
	END;

	TYPE MailMessage = OBJECT
		SUPERTYPES Header
	 METHODS
		FUNCTIONAL id(): MessageId;
		FUNCTIONAL date(): Date;
		FUNCTIONAL from(): AddressSeq;
		FUNCTIONAL to(): AddressSeq;
		FUNCTIONAL body(): Rd.T;
	END;

	type MessageId = ilu.CString;
	type Address = ilu.CString;
	type AddressSeq = SEQUENCE of Address;
	type Date = ilu.CString; @@parser

	TYPE Id = ilu.CString; (* no spaces, : *)

	TYPE HeaderFields = SEQUENCE OF HeaderField;
	TYPE HeaderField = RECORD
		name: Id;
		value: FieldValue;
	END;

	TYPE FieldValue = ilu.CString;
			(* any newlines must be followed
				by whitespace *)
END;

INTERFACE MIME
	imports RFC822;

	TYPE MediaType = ilu.CString;
	(* @@parser ala uri perser
		matching algorithm *)

	TYPE BodyPart = OBJECT
		SUPERTYPES RFC822.Header
		METHODS
		FUNCTIONAL mediaType(): MediaType;
		 description(): RFC822.FieldValue;
		FUNCTIONAL length(): integer
			RAISES Unknown;
		FUNCTIONAL body(): Rd.T;
	END;

	TYPE MultiPart = OBJECT
			SUPERTYPES BodyPart
			METHODS
		nthPart(n: integer)
			RAISES CannotSeek;
	END:
	
END;


INTERFACE URI;

	TYPE T = ilu.CString; (* no spaces *)

	TYPE Parser = SINGLETON OBJECT

		scheme(i: T) : Scheme
			RAISES SyntaxError;

		contact(i: T, OUT port: integer,
						OUT user: String,
						OUT passwd: String) : 
							HostName RAISES SyntaxError;

		path(i: T): Path;

		join(here, delta: T) : T
				 RAISES SyntaxError;

		subtract(here, there) : T
				 RAISES SyntaxError;
	END;

	TYPE Path = ilu.CString;

	TYPE Scheme = OBJECT METHODS
		FUNCTIONAL name(): String;
				(*@@ what chars allowed?*)
	END;

END;

(****************************)
(* SGML scanner *)


INTERFACE SGML
	imports scanner, parser;

  TYPE Scanner = Scanner.T;
  TYPE Parser = Parser.T;

	TYPE Name = ilu.CString (* syntax depends
			on SGML decl in effect... *)

  TYPE Oracle = OBJECT METHODS
  	attrValue(name: Name;
  				symbols: IntSeq,
  				tokens: TextSeq,
  				OUT value: ilu.CString) : BOOL;
	END;
END;

INTERFACE Scanner;

	TYPE Target = OBJECT METHODS
		construct(symbols: IntSeq,
  						tokens: TextSeq);
  END;

  TYPE T = OBJECT METHODS
  	text(d: Text; t: Target,
  			INOUT state: integer);
  END;
  
  TYPE Text = ilu.CString;
END;

INTERFACE Parser;
  TYPE Target = OBJECT METHODS
    node(tree: SExpr)
  END;
  
  TYPE T = OBJECT METHODS
    construct(symbols: IntSeq,
  						tokens: TextSeq);
	END;
END;