// dojo toolkit based flickr support
// (C) Copyright Ian Mckellar 2007, All Rights Reseved
// Contact ian@mckellar.org for licensing.

dojo.require('dojo.crypto.MD5');
var flickr = {};
flickr.debug = false;
flickr._api_key = null;
flickr._secret_key = null;
flickr._url = function flickr_url (args, type) {
    if (!type) { type = 'rest'; }
    var url = 'http://api.flickr.com/services/'+type+'/?'
    var signature = flickr._secret_key;
    var keys = new Array ();
    for (var k in args) { keys.push (k); }
    keys.sort ();
    for (var i=0; i<keys.length; i++) {
        var k = keys[i];
        var v = args[k];
        signature = signature + k + v;
        url = url + (i>0?'&':'') + escape(k) + '=' + escape(v);
    }
    signature = dojo.crypto.MD5.compute(signature, dojo.crypto.outputTypes.Hex);
    url = url + '&api_sig='+signature;
    return url;
}
flickr._callbacks = {},
flickr._callback_number = 1,
flickr.keys = function flickr_keys (api_key, secret_key) {
    flickr._api_key = api_key;
    flickr._secret_key = secret_key;
}
flickr.call = function flickr_call (args, callback) {
    args.api_key = flickr._api_key;
    args.format = 'json';
    if (callback) {
        var cb_id = 'cb'+flickr._callback_number;
        flickr._callbacks[cb_id] = function (rsp) { 
            delete (flickr._callbacks[cb_id]);
            callback (rsp);
        }
        args.jsoncallback = 'flickr._callbacks.'+cb_id;
        flickr._callback_number++;
    } else {
        args.nojsoncallback=1;
    }
    if (flickr._auto_token) { args.auth_token = token; }
    // FIXME: does this work in IE?
    // FIXME: onerror or timeout for the script load?
    // FIXME: look at ScriptSrcTransport?
    var script = document.createElement ('script');
    script.setAttribute ('type', 'text/javascript');
    flickr.debug && dojo.debug ('flickr.call: '+args.toSource());
    script.setAttribute ('src', flickr._url (args));
    document.body.appendChild (script);
}