+/**
+ * Takes an options object for configuration (consumer_key,
+ * consumer_secret, version, signature_method, token) and returns a
+ * function that generates the Authorization header for given data.
+ *
+ * The returned function takes these parameters:
+ * - method: GET/POST/...
+ * - uri: full URI with protocol, port, path and query string
+ * - extra_params: any extra parameters (that are passed in the POST data),
+ * can be an object or a from-urlencoded string.
+ *
+ * Returned function returns full OAuth header with "OAuth" string in it.
+ */
+
+ohauth.headerGenerator = function(options) {
+ options = options || {};
+ var consumer_key = options.consumer_key || '',
+ consumer_secret = options.consumer_secret || '',
+ signature_method = options.signature_method || 'HMAC-SHA1',
+ version = options.version || '1.0',
+ token = options.token || '';
+
+ return function(method, uri, extra_params) {
+ method = method.toUpperCase();
+ if (typeof extra_params === 'string' && extra_params.length > 0) {
+ extra_params = ohauth.stringQs(extra_params);
+ }
+
+ var uri_parts = uri.split('?', 2),
+ base_uri = uri_parts[0];
+
+ var query_params = uri_parts.length === 2 ?
+ ohauth.stringQs(uri_parts[1]) : {};
+
+ var oauth_params = {
+ oauth_consumer_key: consumer_key,
+ oauth_signature_method: signature_method,
+ oauth_version: version,
+ oauth_timestamp: ohauth.timestamp(),
+ oauth_nonce: ohauth.nonce()
+ };
+
+ if (token) oauth_params.oauth_token = token;
+
+ var all_params = xtend({}, oauth_params, query_params, extra_params),
+ base_str = ohauth.baseString(method, base_uri, all_params);
+
+ oauth_params.oauth_signature = ohauth.signature(consumer_secret, token, base_str);
+
+ return 'OAuth ' + ohauth.authHeader(oauth_params);
+ };
+};
+