// Copyright 2011 The Go Authors.  All rights reserved.

// Use of this source code is governed by a BSD-style

// license that can be found in the LICENSE file.

package xmpp

import (

	"fmt"

	"io"

	"os"

	"xml"

)

// This file contains support for roster management, RFC 3921, Section 7.

type RosterIq struct {

	Iq

	Query RosterQuery

}

var _ ExtendedStanza = &RosterIq{}

// Roster query/result

type RosterQuery struct {

	// Should always be NsRoster, "query"

	XMLName xml.Name

	Item []RosterItem

}

// See RFC 3921, Section 7.1.

type RosterItem struct {

	// Should always be "item"

	XMLName xml.Name

	Jid string `xml:"attr"`

	Subscription string `xml:"attr"`

	Name string `xml:"attr"`

	Group []string

}

func (riq *RosterIq) InnerMarshal(w io.Writer) os.Error {

	return xml.Marshal(w, riq.Query)

}

// Implicitly becomes part of NewClient's extStanza arg.

func rosterStanza(name *xml.Name) ExtendedStanza {

	return &RosterIq{}

}

// Synchronously fetch this entity's roster from the server and cache

// that information.

func (cl *Client) fetchRoster() os.Error {

	iq := &RosterIq{Iq: Iq{From: cl.Jid.String(), Id: <- cl.Id,

		Type: "get"}, Query: RosterQuery{XMLName:

			xml.Name{Local: "query", Space: NsRoster}}}

	ch := make(chan os.Error)

	f := func(st Stanza) bool {

		iq, ok := st.(*RosterIq)

		if !ok {

			ch <- os.NewError(fmt.Sprintf(

				"Roster query result not iq: %v", st))

			return false

		}

		if iq.Type == "error" {

			ch <- iq.Error

			return false

		}

		q := iq.Query

		cl.roster = make(map[string] *RosterItem, len(q.Item))

		for _, item := range(q.Item) {

			cl.roster[item.Jid] = &item

		}

		ch <- nil

		return false

	}

	cl.HandleStanza(iq.Id, f)

	cl.Out <- iq

	// Wait for f to complete.

	return <- ch

}

// BUG(cjyar) The roster isn't actually updated when things change.

// Returns the current roster of other entities which this one has a

// relationship with. Changes to the roster will be signaled by an

// appropriate Iq appearing on Client.In. See RFC 3921, Section 7.4.

func (cl *Client) Roster() map[string] *RosterItem {

	r := make(map[string] *RosterItem)

	for key, val := range(cl.roster) {

		r[key] = val

	}

	return r

}