// Copyright (c) 2009 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

/**
 * @fileoverview Profiler processor is used to process log file produced
 * by V8 and produce an internal profile representation which is used
 * for building profile views in 'Profiles' tab.
 */
goog.provide('devtools.profiler.Processor');


/**
 * Creates a Profile View builder object compatible with WebKit Profiler UI.
 *
 * @param {number} samplingRate Number of ms between profiler ticks.
 * @constructor
 */
devtools.profiler.WebKitViewBuilder = function(samplingRate) {
  devtools.profiler.ViewBuilder.call(this, samplingRate);
};
goog.inherits(devtools.profiler.WebKitViewBuilder,
    devtools.profiler.ViewBuilder);


/**
 * @override
 */
devtools.profiler.WebKitViewBuilder.prototype.createViewNode = function(
    funcName, totalTime, selfTime, head) {
  return new devtools.profiler.WebKitViewNode(
      funcName, totalTime, selfTime, head);
};


/**
 * Constructs a Profile View node object for displaying in WebKit Profiler UI.
 *
 * @param {string} internalFuncName A fully qualified function name.
 * @param {number} totalTime Amount of time that application spent in the
 *     corresponding function and its descendants (not that depending on
 *     profile they can be either callees or callers.)
 * @param {number} selfTime Amount of time that application spent in the
 *     corresponding function only.
 * @param {devtools.profiler.ProfileView.Node} head Profile view head.
 * @constructor
 */
devtools.profiler.WebKitViewNode = function(
    internalFuncName, totalTime, selfTime, head) {
  devtools.profiler.ProfileView.Node.call(this,
      internalFuncName, totalTime, selfTime, head);
  this.initFuncInfo_();
  this.callUID = internalFuncName;
};
goog.inherits(devtools.profiler.WebKitViewNode,
    devtools.profiler.ProfileView.Node);


/**
 * RegEx for stripping V8's prefixes of compiled functions.
 */
devtools.profiler.WebKitViewNode.FUNC_NAME_STRIP_RE =
    /^(?:LazyCompile|Function): (.*)$/;


/**
 * RegEx for extracting script source URL and line number.
 */
devtools.profiler.WebKitViewNode.FUNC_NAME_PARSE_RE =
    /^([^ ]+) (.*):(\d+)( \{\d+\})?$/;


/**
 * Inits 'functionName', 'url', and 'lineNumber' fields using 'internalFuncName'
 * field.
 * @private
 */
devtools.profiler.WebKitViewNode.prototype.initFuncInfo_ = function() {
  var nodeAlias = devtools.profiler.WebKitViewNode;
  this.functionName = this.internalFuncName;

  var strippedName = nodeAlias.FUNC_NAME_STRIP_RE.exec(this.functionName);
  if (strippedName) {
    this.functionName = strippedName[1];
  }

  var parsedName = nodeAlias.FUNC_NAME_PARSE_RE.exec(this.functionName);
  if (parsedName) {
    this.functionName = parsedName[1];
    if (parsedName[4]) {
      this.functionName += parsedName[4];
    }
    this.url = parsedName[2];
    this.lineNumber = parsedName[3];
  } else {
    this.url = '';
    this.lineNumber = 0;
  }
};


/**
 * Ancestor of a profile object that leaves out only JS-related functions.
 * @constructor
 */
devtools.profiler.JsProfile = function() {
  devtools.profiler.Profile.call(this);
};
goog.inherits(devtools.profiler.JsProfile, devtools.profiler.Profile);


/**
 * RegExp that leaves only JS functions.
 * @type {RegExp}
 */
devtools.profiler.JsProfile.JS_FUNC_RE = /^(LazyCompile|Function|Script):/;

/**
 * RegExp that filters out native code (ending with "native src.js:xxx").
 * @type {RegExp}
 */
devtools.profiler.JsProfile.JS_NATIVE_FUNC_RE = /\ native\ \w+\.js:\d+$/;

/**
 * RegExp that filters out native scripts.
 * @type {RegExp}
 */
devtools.profiler.JsProfile.JS_NATIVE_SCRIPT_RE = /^Script:\ native/;


/**
 * @override
 */
devtools.profiler.JsProfile.prototype.skipThisFunction = function(name) {
  return !devtools.profiler.JsProfile.JS_FUNC_RE.test(name) ||
      // To profile V8's natives comment out two lines below and '||' above.
      devtools.profiler.JsProfile.JS_NATIVE_FUNC_RE.test(name) ||
      devtools.profiler.JsProfile.JS_NATIVE_SCRIPT_RE.test(name);
};


/**
 * Profiler processor. Consumes profiler log and builds profile views.
 *
 * @param {function(devtools.profiler.ProfileView)} newProfileCallback Callback
 *     that receives a new processed profile.
 * @constructor
 */
devtools.profiler.Processor = function() {
  devtools.profiler.LogReader.call(this, {
      'code-creation': {
          parsers: [null, this.createAddressParser('code'), parseInt, null],
          processor: this.processCodeCreation_, backrefs: true,
          needsProfile: true },
      'code-move': { parsers: [this.createAddressParser('code'),
          this.createAddressParser('code-move-to')],
          processor: this.processCodeMove_, backrefs: true,
          needsProfile: true },
      'code-delete': { parsers: [this.createAddressParser('code')],
          processor: this.processCodeDelete_, backrefs: true,
          needsProfile: true },
      'tick': { parsers: [this.createAddressParser('code'),
          this.createAddressParser('stack'), parseInt, 'var-args'],
          processor: this.processTick_, backrefs: true, needProfile: true },
      'profiler': { parsers: [null, 'var-args'],
          processor: this.processProfiler_, needsProfile: false },
      'heap-sample-begin': { parsers: [null, null, parseInt],
          processor: this.processHeapSampleBegin_ },
      'heap-sample-stats': { parsers: [null, null, parseInt, parseInt],
          processor: this.processHeapSampleStats_ },
      'heap-sample-item': { parsers: [null, parseInt, parseInt],
          processor: this.processHeapSampleItem_ },
      'heap-js-cons-item': { parsers: [null, parseInt, parseInt],
          processor: this.processHeapJsConsItem_ },
      'heap-js-ret-item': { parsers: [null, 'var-args'],
          processor: this.processHeapJsRetItem_ },
      'heap-sample-end': { parsers: [null, null],
          processor: this.processHeapSampleEnd_ },
      // Not used in DevTools Profiler.
      'shared-library': null,
      // Obsolete row types.
      'code-allocate': null,
      'begin-code-region': null,
      'end-code-region': null});


  /**
   * Callback that is called when a new profile is encountered in the log.
   * @type {function()}
   */
  this.startedProfileProcessing_ = null;

  /**
   * Callback that is called periodically to display processing status.
   * @type {function()}
   */
  this.profileProcessingStatus_ = null;

  /**
   * Callback that is called when a profile has been processed and is ready
   * to be shown.
   * @type {function(devtools.profiler.ProfileView)}
   */
  this.finishedProfileProcessing_ = null;

  /**
   * The current profile.
   * @type {devtools.profiler.JsProfile}
   */
  this.currentProfile_ = null;

  /**
   * Builder of profile views. Created during "profiler,begin" event processing.
   * @type {devtools.profiler.WebKitViewBuilder}
   */
  this.viewBuilder_ = null;

  /**
   * Next profile id.
   * @type {number}
   */
  this.profileId_ = 1;

  /**
   * Counter for processed ticks.
   * @type {number}
   */
  this.ticksCount_ = 0;

  /**
   * The current heap snapshot.
   * @type {string}
   */
  this.currentHeapSnapshot_ = null;

  /**
   * Next heap snapshot id.
   * @type {number}
   */
  this.heapSnapshotId_ = 1;
};
goog.inherits(devtools.profiler.Processor, devtools.profiler.LogReader);


/**
 * @override
 */
devtools.profiler.Processor.prototype.printError = function(str) {
  debugPrint(str);
};


/**
 * @override
 */
devtools.profiler.Processor.prototype.skipDispatch = function(dispatch) {
  return dispatch.needsProfile && this.currentProfile_ == null;
};


/**
 * Sets profile processing callbacks.
 *
 * @param {function()} started Started processing callback.
 * @param {function(devtools.profiler.ProfileView)} finished Finished
 *     processing callback.
 */
devtools.profiler.Processor.prototype.setCallbacks = function(
    started, processing, finished) {
  this.startedProfileProcessing_ = started;
  this.profileProcessingStatus_ = processing;
  this.finishedProfileProcessing_ = finished;
};


/**
 * An address for the fake "(program)" entry. WebKit's visualisation
 * has assumptions on how the top of the call tree should look like,
 * and we need to add a fake entry as the topmost function. This
 * address is chosen because it's the end address of the first memory
 * page, which is never used for code or data, but only as a guard
 * page for catching AV errors.
 *
 * @type {number}
 */
devtools.profiler.Processor.PROGRAM_ENTRY = 0xffff;
/**
 * @type {string}
 */
devtools.profiler.Processor.PROGRAM_ENTRY_STR = '0xffff';


/**
 * Sets new profile callback.
 * @param {function(devtools.profiler.ProfileView)} callback Callback function.
 */
devtools.profiler.Processor.prototype.setNewProfileCallback = function(
    callback) {
  this.newProfileCallback_ = callback;
};


devtools.profiler.Processor.prototype.processProfiler_ = function(
    state, params) {
  var processingInterval = null;
  switch (state) {
    case 'resume':
      if (this.currentProfile_ == null) {
        this.currentProfile_ = new devtools.profiler.JsProfile();
        // see the comment for devtools.profiler.Processor.PROGRAM_ENTRY
        this.currentProfile_.addCode(
          'Function', '(program)',
          devtools.profiler.Processor.PROGRAM_ENTRY, 1);
        if (this.startedProfileProcessing_) {
          this.startedProfileProcessing_();
        }
        this.ticksCount_ = 0;
        var self = this;
        if (this.profileProcessingStatus_) {
          processingInterval = window.setInterval(
              function() { self.profileProcessingStatus_(self.ticksCount_); },
              1000);
        }
      }
      break;
    case 'pause':
      if (this.currentProfile_ != null) {
        window.clearInterval(processingInterval);
        if (this.finishedProfileProcessing_) {
          this.finishedProfileProcessing_(this.createProfileForView());
        }
        this.currentProfile_ = null;
      }
      break;
    case 'begin':
      var samplingRate = NaN;
      if (params.length > 0) {
        samplingRate = parseInt(params[0]);
      }
      if (isNaN(samplingRate)) {
        samplingRate = 1;
      }
      this.viewBuilder_ = new devtools.profiler.WebKitViewBuilder(samplingRate);
      break;
    // These events are valid but aren't used.
    case 'compression':
    case 'end': break;
    default:
      throw new Error('unknown profiler state: ' + state);
  }
};


devtools.profiler.Processor.prototype.processCodeCreation_ = function(
    type, start, size, name) {
  this.currentProfile_.addCode(this.expandAlias(type), name, start, size);
};


devtools.profiler.Processor.prototype.processCodeMove_ = function(from, to) {
  this.currentProfile_.moveCode(from, to);
};


devtools.profiler.Processor.prototype.processCodeDelete_ = function(start) {
  this.currentProfile_.deleteCode(start);
};


devtools.profiler.Processor.prototype.processTick_ = function(
    pc, sp, vmState, stack) {
  // see the comment for devtools.profiler.Processor.PROGRAM_ENTRY
  stack.push(devtools.profiler.Processor.PROGRAM_ENTRY_STR);
  this.currentProfile_.recordTick(this.processStack(pc, stack));
  this.ticksCount_++;
};


devtools.profiler.Processor.prototype.processHeapSampleBegin_ = function(
    space, state, ticks) {
  if (space != 'Heap') return;
  this.currentHeapSnapshot_ = {
      number: this.heapSnapshotId_++,
      entries: {},
      clusters: {},
      lowlevels: {},
      ticks: ticks
  };
};


devtools.profiler.Processor.prototype.processHeapSampleStats_ = function(
    space, state, capacity, used) {
  if (space != 'Heap') return;
  this.currentHeapSnapshot_.capacity = capacity;
  this.currentHeapSnapshot_.used = used;
};


devtools.profiler.Processor.prototype.processHeapSampleItem_ = function(
    item, number, size) {
  if (!this.currentHeapSnapshot_) return;
  this.currentHeapSnapshot_.lowlevels[item] = {
    type: item, count: number, size: size
  };
};


devtools.profiler.Processor.prototype.processHeapJsConsItem_ = function(
    item, number, size) {
  if (!this.currentHeapSnapshot_) return;
  this.currentHeapSnapshot_.entries[item] = {
    cons: item, count: number, size: size, retainers: {}
  };
};


devtools.profiler.Processor.prototype.processHeapJsRetItem_ = function(
    item, retainersArray) {
  if (!this.currentHeapSnapshot_) return;
  var rawRetainers = {};
  for (var i = 0, n = retainersArray.length; i < n; ++i) {
    var entry = retainersArray[i].split(';');
    rawRetainers[entry[0]] = parseInt(entry[1], 10);
  }

  function mergeRetainers(entry) {
    for (var rawRetainer in rawRetainers) {
      var consName = rawRetainer.indexOf(':') != -1 ?
          rawRetainer.split(':')[0] : rawRetainer;
      if (!(consName in entry.retainers))
        entry.retainers[consName] = { cons: consName, count: 0, clusters: {} };
      var retainer = entry.retainers[consName];
      retainer.count += rawRetainers[rawRetainer];
      if (consName != rawRetainer)
        retainer.clusters[rawRetainer] = true;
    }
  }

  if (item.indexOf(':') != -1) {
    // Array, Function, or Object instances cluster case.
    if (!(item in this.currentHeapSnapshot_.clusters)) {
      this.currentHeapSnapshot_.clusters[item] = {
        cons: item, retainers: {}
      };
    }
    mergeRetainers(this.currentHeapSnapshot_.clusters[item]);
    item = item.split(':')[0];
  }
  mergeRetainers(this.currentHeapSnapshot_.entries[item]);
};


devtools.profiler.Processor.prototype.processHeapSampleEnd_ = function(
    space, state) {
  if (space != 'Heap') return;
  var snapshot = this.currentHeapSnapshot_;
  this.currentHeapSnapshot_ = null;
  // For some reason, 'used' from 'heap-sample-stats' sometimes differ from
  // the sum of objects sizes. To avoid discrepancy, we re-calculate 'used'.
  snapshot.used = 0;
  for (var item in snapshot.lowlevels) {
      snapshot.used += snapshot.lowlevels[item].size;
  }
  WebInspector.panels.profiles.addSnapshot(snapshot);
};


/**
 * Creates a profile for further displaying in ProfileView.
 */
devtools.profiler.Processor.prototype.createProfileForView = function() {
  var profile = this.viewBuilder_.buildView(
      this.currentProfile_.getTopDownProfile());
  profile.uid = this.profileId_++;
  profile.title = UserInitiatedProfileName + '.' + profile.uid;
  return profile;
};