/*jslint indent: 2, nomen: true, maxlen: 100, sloppy: true, vars: true, white: true, plusplus: true, evil: true */
/*global require, exports, module */

////////////////////////////////////////////////////////////////////////////////
/// @brief administration actions
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2010-2012 triagens GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is triAGENS GmbH, Cologne, Germany
///
/// @author Dr. Frank Celler
/// @author Copyright 2012, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////

var arangodb = require("org/arangodb");
var actions = require("org/arangodb/actions");

var db = arangodb.db;

var internal = require("internal");
var console = require("console");

// -----------------------------------------------------------------------------
// --SECTION--                                                 private functions
// -----------------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////////////
/// @addtogroup ArangoAPI
/// @{
////////////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////////////
/// @brief routing function
////////////////////////////////////////////////////////////////////////////////

function routing (req, res) {
  var action;
  var execute;
  var next;
  var path = req.suffix.join("/");

  action = actions.firstRouting(req.requestType, req.suffix);

  execute = function () {
    if (action.route === undefined) {
      actions.resultNotFound(req, res, arangodb.ERROR_HTTP_NOT_FOUND, 
        "unknown path '" + path + "'");
      return;
    }

    if (action.route.path !== undefined) {
      req.path = action.route.path;
    }
    else {
      delete req.path;
    }

    if (action.prefix !== undefined) {
      req.prefix = action.prefix;
    }
    else {
      delete req.prefix;
    }

    if (action.suffix !== undefined) {
      req.suffix = action.suffix;
    }
    else {
      delete req.suffix;
    }

    if (action.urlParameters !== undefined) {
      req.urlParameters = action.urlParameters;
    }
    else {
      req.urlParameters = {};
    }

    var func = action.route.callback.controller;
    if (func === null || typeof func !== 'function') {
      func = actions.errorFunction(action.route,
                                   'Invalid callback definition found for route ' 
                                   + JSON.stringify(action.route));
    }

    try {
      func(req, res, action.route.callback.options, next);
    }
    catch (err) {
      var msg = 'A runtime error occurred while executing an action: '
                + String(err) + " " + String(err.stack);

      actions.errorFunction(action.route, msg)(req, res, action.route.callback.options, next);
    }
  };

  next = function () {
    action = actions.nextRouting(action);
    execute();
  };

  execute();
}

////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////

// -----------------------------------------------------------------------------
// --SECTION--                                                  public functions
// -----------------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////////////
/// @addtogroup ArangoAPI
/// @{
////////////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////////////
/// @brief main routing action
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "",
  prefix : true,
  context : "admin",

  callback : routing
});

////////////////////////////////////////////////////////////////////////////////
/// @brief reloads the server authentication information
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/auth/reload",
  context : "admin",
  prefix : false,

  callback : function (req, res) {
    internal.reloadAuth();
    actions.resultOk(req, res, actions.HTTP_OK);
  }
});

////////////////////////////////////////////////////////////////////////////////
/// @fn JSF_GET_admin_routing_reloads
/// @brief reloads the routing information
///
/// @RESTHEADER{POST /_admin/routing/reload,reloads the routing collection}
///
/// @REST{POST /_admin/routing/reload}
///
/// The reloads the routing information from the collection `routing`.
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/routing/reload",
  context : "admin",
  prefix : false,

  callback : function (req, res) {
    internal.executeGlobalContextFunction("require(\"org/arangodb/actions\").reloadRouting()");
    console.warn("about to flush the routing cache");
    actions.resultOk(req, res, actions.HTTP_OK);
  }
});

////////////////////////////////////////////////////////////////////////////////
/// @brief returns the current routing information 
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/routing/routes",
  context : "admin",
  prefix : false,

  callback : function (req, res) {
    actions.resultOk(req, res, actions.HTTP_OK, actions.routingCache());
  }
});

////////////////////////////////////////////////////////////////////////////////
/// @fn JSF_GET_admin_modules_flush
/// @brief flushes the modules cache
///
/// @RESTHEADER{POST /_admin/modules/flush,flushs the module cache}
///
/// @REST{POST /_admin/modules/flush}
///
/// The call flushes the modules cache on the server. See @ref JSModulesCache
/// for details about this cache.
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/modules/flush",
  context : "admin",
  prefix : false,

  callback : function (req, res) {
    internal.executeGlobalContextFunction("require(\"internal\").flushModuleCache()");
    console.warn("about to flush the modules cache");
    actions.resultOk(req, res, actions.HTTP_OK);
  }
});

////////////////////////////////////////////////////////////////////////////////
/// @fn JSF_GET_admin_time
/// @brief returns the system time
///
/// @RESTHEADER{GET /_admin/time,returns the system time}
///
/// @REST{GET /_admin/time}
///
/// The call returns an object with the attribute @LIT{time}. This contains the
/// current system time as a Unix timestamp with microsecond precision.
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/time",
  context : "admin",
  prefix : false,

  callback : function (req, res) {
    actions.resultOk(req, res, actions.HTTP_OK, { time : internal.time() });
  }
});

////////////////////////////////////////////////////////////////////////////////
/// @fn JSF_GET_admin_echo
/// @brief returns the request
///
/// @RESTHEADER{GET /_admin/echo,returns the current request}
///
/// @REST{GET /_admin/echo}
///
/// The call returns an object with the following attributes:
///
/// - @LIT{headers}: a list of HTTP headers received
///
/// - @LIT{requestType}: the HTTP request method (e.g. GET)
///
/// - @LIT{parameters}: list of URL parameters received
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/echo",
  context : "admin",
  prefix : true,

  callback : function (req, res) {
    res.responseCode = actions.HTTP_OK;
    res.contentType = "application/json; charset=utf-8";
    res.body = JSON.stringify(req);
  }
});

////////////////////////////////////////////////////////////////////////////////
/// @fn JSF_GET_admin_statistics
/// @brief returns system status information for the server
///
/// @RESTHEADER{GET /_admin/statistics,reads the statistics}
///
/// @RESTDESCRIPTION
/// Returns the statistics information. The returned objects contains the
/// statistics figures group together according to the description returned by
/// `_admin/statistics-description`. For instance, to access a figure `userTime`
/// from the group `system`, you first select the sub-object describing the
/// group stored in `system` and in that sub-object the value for `userTime` is
/// stored in the attribute of the same name.
///
/// In case of a distribution, the returned object contains the total count in
/// `count` and the distribution list in `counts`.
/// 
/// @RESTRETURNCODES
/// 
/// @RESTRETURNCODE{200}
/// Statistics was returned successfully.
/// 
/// @EXAMPLES
/// 
/// @EXAMPLE_ARANGOSH_RUN{AdminStatistics1}
///     var url = "/_admin/statistics";
///     var response = logCurlRequest('GET', url);
/// 
///     assert(response.code === 200);
/// 
///     logJsonResponse(response);
/// @END_EXAMPLE_ARANGOSH_RUN
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/statistics",
  context : "admin",
  prefix : false,

  callback : function (req, res) {
    var result;

    try {
      result = {};
      result.system = internal.processStat();
      result.client = internal.requestStatistics();

      actions.resultOk(req, res, actions.HTTP_OK, result);
    }
    catch (err) {
      actions.resultException(req, res, err);
    }
  }
});

////////////////////////////////////////////////////////////////////////////////
/// @fn JSF_GET_admin_statistics_description
/// @brief returns statistics description
///
/// @RESTHEADER{GET /_admin/statistics-description,statistics description}
/// 
/// @RESTDESCRIPTION
/// Returns a description of the statistics returned by `/_admin/statistics`.
/// The returned objects contains a list of statistics groups in the attribute
/// `groups` and a list of statistics figures in the attribute `figures`.
///
/// A statistics group is described by
///
/// - `group`: The identifier of the group.
/// - `name`: The name of the group.
/// - `description`: A description of the group.
///
/// A statistics figure is described by
///
/// - `group`: The identifier of the group to which this figure belongs.
/// - `identifier`: The identifier of the figure. It is unique within the group.
/// - `name`: The name of the figure.
/// - `description`: A description of the group.
/// - `type`: Either `current`, `accumulated`, or `distribution`.
/// - `cuts`: The distribution vector.
/// - `units`: Units in which the figure is measured.
///
/// @RESTRETURNCODES
/// 
/// @RESTRETURNCODE{200}
/// Description was returned successfully.
/// 
/// @EXAMPLES
/// 
/// @EXAMPLE_ARANGOSH_RUN{AdminStatisticsDescription1}
///     var url = "/_admin/statistics-description";
///     var response = logCurlRequest('GET', url);
/// 
///     assert(response.code === 200);
/// 
///     logJsonResponse(response);
/// @END_EXAMPLE_ARANGOSH_RUN
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/statistics-description",
  context : "admin",
  prefix : false,

  callback : function (req, res) {
    var result;

    try {
      result = {
        groups: [
          {
            group: "system",
            name: "Process Statistics",
            description: "Statistics about the ArangoDB process"
          },

          {
            group: "client",
            name: "Client Statistics",
            description: "Statistics about the clients connecting to the server."
          }
        ],

        figures: [

          // .............................................................................
          // system statistics
          // .............................................................................

          {
            group: "system",
            identifier: "userTime",
            name: "User Time",
            description: "Amount of time that this process has been scheduled in user mode, " + 
                         "measured in clock ticks divided by sysconf(_SC_CLK_TCK) aka seconds.",
            type: "accumulated",
            units: "seconds"
          },

          {
            group: "system",
            identifier: "systemTime",
            name: "System Time",
            description: "Amount of time that this process has been scheduled in kernel mode, " +
                         "measured in clock ticks divided by sysconf(_SC_CLK_TCK) aka seconds.",
            type: "accumulated",
            units: "seconds"
          },

          {
            group: "system",
            identifier: "numberOfThreads",
            name: "Number of Threads",
            description: "Number of threads in this process.",
            type: "current",
            units: "number"
          },

          {
            group: "system",
            identifier: "residentSize",
            name: "Resident Set Size",
            description: "The number of pages the process has in real memory. " + 
                         "This is just the pages which count toward text, data, or stack space. " +
                         "This does not include pages which have not been demand-loaded in, " +
                         "or which are swapped out.",
            type: "current",
            units: "bytes"
          },

          {
            group: "system",
            identifier: "virtualSize",
            name: "Virtual Memory Size",
            description: "The size of the virtual memory the process is using.",
            type: "current",
            units: "bytes"
          },

          {
            group: "system",
            identifier: "minorPageFaults",
            name: "Minor Page Faults",
            description: "The number of minor faults the process has made which have " +
                         "not required loading a memory page from disk.",
            type: "accumulated",
            units: "number"
          },

          {
            group: "system",
            identifier: "majorPageFaults",
            name: "Major Page Faults",
            description: "The number of major faults the process has made which have required " +
                         "loading a memory page from disk.",
            type: "accumulated",
            units: "number"
          },

          // .............................................................................
          // client statistics
          // .............................................................................

          {
            group: "client",
            identifier: "httpConnections",
            name: "HTTP Client Connections",
            description: "The number of http connections that are currently open.",
            type: "current",
            units: "number"
          },

          {
            group: "client",
            identifier: "totalTime",
            name: "Total Time",
            description: "Total time needed to answer a request.",
            type: "distribution",
            cuts: internal.requestTimeDistribution,
            units: "seconds"
          },

          {
            group: "client",
            identifier: "requestTime",
            name: "Request Time",
            description: "Request time needed to answer a request.",
            type: "distribution",
            cuts: internal.requestTimeDistribution,
            units: "seconds"
          },

          {
            group: "client",
            identifier: "queueTime",
            name: "Queue Time",
            description: "Queue time needed to answer a request.",
            type: "distribution",
            cuts: internal.requestTimeDistribution,
            units: "seconds"
          },

          {
            group: "client",
            identifier: "bytesSent",
            name: "Bytes Sent",
            description: "Bytes sents for a request.",
            type: "distribution",
            cuts: internal.bytesSentDistribution,
            units: "bytes"
          },

          {
            group: "client",
            identifier: "bytesReceived",
            name: "Bytes Received",
            description: "Bytes receiveds for a request.",
            type: "distribution",
            cuts: internal.bytesReceivedDistribution,
            units: "bytes"
          },

          {
            group: "client",
            identifier: "connectionTime",
            name: "Connection Time",
            description: "Total connection time of a client.",
            type: "distribution",
            cuts: internal.connectionTimeDistribution,
            units: "seconds"
          }
        ]
      };

      actions.resultOk(req, res, actions.HTTP_OK, result);
    }
    catch (err) {
      actions.resultException(req, res, err);
    }
  }
});

////////////////////////////////////////////////////////////////////////////////
/// @fn JSF_GET_admin_execute
/// @brief executes a JavaScript program on the server
///
/// @RESTHEADER{POST /_admin/execute,executes a program}
///
/// Executes the body on the server.
////////////////////////////////////////////////////////////////////////////////

actions.defineHttp({
  url : "_admin/execute",
  context : "admin",
  prefix : false,

  callback : function (req, res) {
    var body = req.requestBody;
    var result;

    console.warn("about to execute: '%s'", body);

    if (body !== "") {
      result = eval("(function() {" + body + "}());");
    }

    actions.resultOk(req, res, actions.HTTP_OK, JSON.stringify(result));
  }
});


////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////

// -----------------------------------------------------------------------------
// --SECTION--                                                       END-OF-FILE
// -----------------------------------------------------------------------------

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