Field.pickContent - Code Metrics - Inspection of "Always cache Agenda data" - jf-guillou/lcds - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( 9a2843...3c69ee )

by Jeff

created 2017-02-13 07:52 UTC

Field.pickContent C

↳ Parent: web/js/frontend.js

Complexity

Conditions	8
Paths	8

Size

Total Lines

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
c	0
b	0
f	0
dl	0
loc	38
rs	5.3846
cc	8
nc	8
nop	2

/** global: updateScreenUrl, navigator */

/**
 * Screen class constructor
 * @param {string} updateScreenUrl global screen update checks url
 */
function Screen(updateScreenUrl) {
  this.fields = [];
  this.url = updateScreenUrl;
  this.lastChanges = null;
  this.endAt = null;
  this.nextUrl = null;
  this.cache = new Preload(navigator.userAgent.toLowerCase().indexOf('kweb') == -1);
  this.runOnce = false;
}

/**
 * Ajax GET on updateScreenUrl to check lastChanges timestamp and reload if necessary
 */
Screen.prototype.checkUpdates = function() {
  var s = this;
  $.get(this.url, function(j) {
    if (j.success) {
      if (s.lastChanges == null) {
        s.lastChanges = j.data.lastChanges;
      } else if (s.lastChanges != j.data.lastChanges) {
        // Remote screen updated, we should reload as soon as possible
        s.nextUrl = null;
        s.reloadIn(0);
        return;
      }

      if (j.data.nextScreenUrl != null) {
        // Setup next screen
        s.nextUrl = j.data.nextScreenUrl;
        if (j.data.duration > 0) {
          s.reloadIn(j.data.duration * 1000);
        } else {
          s.runOnce = true;
        }
      }
    } else if (j.message == 'Unauthorized') {
      // Cookie/session gone bad, try to refresh with full screen reload
      screen.reloadIn(0);
    }
  });
}

/**
 * Start Screen reload procedure, checking for every field timeout
 */
Screen.prototype.reloadIn = function(minDuration) {
  var endAt = Date.now() + minDuration;
  if (this.endAt != null && this.endAt < endAt) {
    // Already going to reload sooner than asked
    return;
  }

  if (this.cache.hasPreloadingContent(true)) {
    // Do not break preloading
    return;
  }

  this.endAt = Date.now() + minDuration;
  for (var i in this.fields) {
    if (!this.fields.hasOwnProperty(i)) {
      continue;
    }
    var f = this.fields[i];
    if (f.timeout && f.endAt > this.endAt) {
      // Always wait for content display end
      this.endAt = f.endAt;
    }
  }

  this.reloadOnTimeout();
}

/**
 * Check if we're past the screen.endAt timeout and reload if necessary
 * @return {boolean} going to reload
 */
Screen.prototype.reloadOnTimeout = function() {
  if (screen.runOnce && screen.hasRanOnce() && !this.cache.hasPreloadingContent(true)) {
    // Every content has been shown, reload
    this.reloadNow();
    return true;
  }

  if (this.endAt != null && Date.now() >= this.endAt) {
    // No content to delay reload, do it now
    this.reloadNow();
    return true;
  }

  return false;
}

/**
 * Actual Screen reload/change screen action
 */
Screen.prototype.reloadNow = function() {
  if (this.nextUrl) {
    window.location = this.nextUrl;
  } else {
    window.location.reload();
  }
}

/**
 * Check every field if contents have been all played at least once
 * @return {Boolean} has every content been played
 */
Screen.prototype.hasRanOnce = function() {
  for (var f in this.fields) {
    if (!this.fields.hasOwnProperty(f)) {
      continue;
    }
    f = this.fields[f];

    for (var c in f.contents) {
      if (!f.contents.hasOwnProperty(c)) {
        continue;
      }
      c = f.contents[c];

      if (f.playCount[c.id] < 1 && c.isPreloaded()) {
        return false;
      }
    }
  }

  return true;
}

/**
 * Check every field for content
 * @param  {Content} data
 * @return {boolean} content is displayed
 */
Screen.prototype.displaysData = function(data) {
  return this.fields.filter(function(field) {
    return field.current && field.current.data == data;
  }).length > 0;
}

/**
 * Trigger pickNext on all fields
 */
Screen.prototype.newContentTrigger = function() {
  for (var f in this.fields) {
    if (!this.fields.hasOwnProperty(f)) {
      continue;
    }

    this.fields[f].pickNextIfNecessary();
  }
}

/**
 * Loop through all fields for stuckiness state
 * @return {boolean} are all fields stuck
 */
Screen.prototype.isAllFieldsStuck = function() {
  for (var f in this.fields) {
    if (!this.fields.hasOwnProperty(f)) {
      continue;
    }

    if (!this.fields[f].stuck && this.fields[f].canUpdate) {
      return false;
    }
  }

  return true;
}


/**
 * Content class constructor
 * @param {array} c content attributes
 */
function Content(c) {
  this.id = c.id;
  this.data = c.data;
  this.duration = c.duration * 1000;
  this.type = c.type;
  this.src = null;

  if (this.shouldPreload()) {
    this.queuePreload();
  }
}

/**
 * Check if content should be ajax preloaded
 * @return {boolean} shoud preload
 */
Content.prototype.shouldPreload = function() {
  return this.canPreload() && !this.isPreloadingOrQueued() && !this.isPreloaded();
}

/**
 * Check if content has pre-loadable material
 * @return {boolean} can preload
 */
Content.prototype.canPreload = function() {
  return this.getResource() && this.type.search(/Video|Image/) != -1;
}

/**
 * Check if content is displayable (preloaded and not too long)
 * @return {boolean} can display
 */
Content.prototype.canDisplay = function() {
  return (screen.endAt == null || Date.now() + this.duration < screen.endAt) && this.isPreloaded() && this.data;
}

/**
 * Extract url from contant data
 * @return {string} resource url
 */
Content.prototype.getResource = function() {
  if (this.src) {
    return this.src;
  }
  var srcMatch = this.data.match(/src="([^"]+)"/);
  if (!srcMatch) {
    // All preloadable content comes with a src attribute
    return false;
  }
  var src = srcMatch[1];
  if (src.indexOf('/') === 0) {
    src = window.location.origin + src;
  }
  if (src.indexOf('http') !== 0) {
    return false;
  }
  // Get rid of fragment
  src = src.replace(/#.*/g, '');

  this.src = src;
  return src;
}

/**
 * Set content cache status
 * @param {string} state preload state
 */
Content.prototype.setPreloadState = function(state) {
  screen.cache.setState(this.getResource(), state);
}

/**
 * Check cache for preload status of content
 * @return {boolean} is preloaded
 */
Content.prototype.isPreloaded = function() {
  if (!this.canPreload()) {
    return true;
  }

  return screen.cache.isPreloaded(this.getResource());
}

/**
 * Check cache for in progress or future preloading
 * @return {boolean} is preloading
 */
Content.prototype.isPreloadingOrQueued = function() {
  return this.isPreloading() || this.isInPreloadQueue();
}

/**
 * Check cache for in progress preloading
 * @return {boolean} is preloading
 */
Content.prototype.isPreloading = function() {
  return screen.cache.isPreloading(this.getResource());
}

/**
 * Check cache for queued preloading
 * @return {boolean} is in preload queue
 */
Content.prototype.isInPreloadQueue = function() {
  return screen.cache.isInPreloadQueue(this.getResource());
}

/**
 * Call to preload content
 */
Content.prototype.preload = function() {
  var src = this.getResource();
  if (!src) {
    return;
  }

  screen.cache.preload(src);
}

/**
 * Preload content or add to preload queue
 */
Content.prototype.queuePreload = function() {
  var src = this.getResource();
  if (!src) {
    return;
  }

  if (screen.cache.hasPreloadingContent(false)) {
    this.setPreloadState(Preload.state.PRELOADING_QUEUE);
  } else {
    this.preload();
  }
}


/**
 * Preload class constructor
 * Build cache map
 * @param {boolean} isModernBrowser does browser support modern tags
 */
function Preload(isModernBrowser) {
  this.cache = {};
  if (isModernBrowser) {
    this.preload = this.preloadPrefetch;
  } else {
    this.preload = this.preloadExternal;
  }
}

/**
 * Preload states
 */
Preload.state = {
  ERR: -1,
  WAIT_PRELOADER: 1,
  PRELOADING: 2,
  PRELOADING_QUEUE: 3,
  OK: 4,
  NO_CONTENT: 5,
  HTTP_FAIL: 6,
}

/**
 * Set resource cache state
 * @param {string} res   resource url
 * @param {int}    state preload state
 */
Preload.prototype.setState = function(res, state) {
  this.cache[res] = state;
}

/**
 * Check resource cache for readyness state
 * @param  {string}  res resource url
 * @return {boolean}     is preloaded
 */
Preload.prototype.isPreloaded = function(res) {
  return this.cache[res] === Preload.state.OK;
}

/**
 * Check resource cache for preloading state
 * @param  {string}  res resource url
 * @return {boolean}     is currently preloading
 */
Preload.prototype.isPreloading = function(res) {
  return this.cache[res] === Preload.state.PRELOADING;
}

/**
 * Check resource cache for queued preloading state
 * @param  {string}  res resource url
 * @return {boolean}     is in preload queue
 */
Preload.prototype.isInPreloadQueue = function(res) {
  return this.cache[res] === Preload.state.PRELOADING_QUEUE;
}

/**
 * Check resource cache for queued preloading state during preloader pick phase
 * @param  {string}  res resource url
 * @return {boolean}     is in preload queue
 */
Preload.prototype.isWaiting = function(res) {
  return this.cache[res] === Preload.state.WAIT_PRELOADER;
}

/**
 * Scan resource cache for preloading resources
 * @param  {boolean} withQueue also check preload queue
 * @return {boolean}           has any resource preloading/in preload queue
 */
Preload.prototype.hasPreloadingContent = function(withQueue) {
  for (var res in this.cache) {
    if (!this.cache.hasOwnProperty(res)) {
      continue;
    }

    if (this.isPreloading(res) || this.isWaiting(res) || (withQueue && this.isInPreloadQueue(res))) {
      return true;
    }
  }

  return false;
}

/**
 * Preload a resource
 * Default implementation waits for preloader pick
 * @param {string} res resource url
 */
Preload.prototype.preload = function(res) {
  this.setState(res, Preload.state.WAIT_PRELOADER);
}

/**
 * Triggered on preloader picked
 * Restarts preload queue processing
 */
Preload.prototype.preloaderReady = function() {
  for (var res in this.cache) {
    if (!this.cache.hasOwnProperty(res)) {
      continue;
    }

    if (this.isWaiting(res)) {
      this.preload(res);
    }
  }
}

/**
 * Preload a resource by calling external preloader
 * @param {string} res resource url
 */
Preload.prototype.preloadExternal = function(res) {
  this.setState(res, Preload.state.PRELOADING);
  $.ajax("http://127.0.0.1:8089/pf?res=" + res).done(function(j) {
    switch (j.state) {
      case Preload.state.OK:

      case Preload.state.NO_CONTENT:
        screen.cache.setState(res, j.state);
        screen.newContentTrigger();
        break;
      case Preload.state.HTTP_FAIL:
        screen.cache.setState(res, j.state);
        break;
      case Preload.state.ERR:
        screen.cache.setState(res, Preload.state.HTTP_FAIL);
        break;
      default:
        return;
    }
    screen.cache.preloadNext();
  }).fail(function() {
    screen.cache.preload = screen.cache.preloadAjax;
    screen.cache.preload(res);
  });
}

/**
 * Preload a resource by addinh a <link rel="prefetch"> tag
 * @param {string} res resource url
 */
Preload.prototype.preloadPrefetch = function(res) {
  this.setState(res, Preload.state.PRELOADING);
  $('body').append(
    $('<link>', {
      rel: 'prefetch',
      href: res
    }).load(function() {
      screen.cache.setState(res, Preload.state.OK);
      screen.newContentTrigger();
      screen.cache.preloadNext();
    }).error(function() {
      screen.cache.setState(res, Preload.state.HTTP_FAIL);
      screen.cache.preloadNext();
    })
  );
}

/**
 * Preload a resource by ajax get on the url
 * Check HTTP return state to validate proper cache
 * @param {string} res resource url
 */
Preload.prototype.preloadAjax = function(res) {
  this.setState(res, Preload.state.PRELOADING);
  $.ajax(res).done(function(data) {
    // Preload success
    if (data === '') {
      screen.cache.setState(res, Preload.state.NO_CONTENT);
    } else {
      screen.cache.setState(res, Preload.state.OK);
    }
    screen.newContentTrigger();
  }).fail(function() {
    // Preload failure
    screen.cache.setState(res, Preload.state.HTTP_FAIL);
  }).always(function() {
    screen.cache.preloadNext();
  });
}

/**
 * Try to preload next resource or trigger preload end event
 */
Preload.prototype.preloadNext = function() {
  var res = screen.cache.next();
  if (res) {
    // Preload ended, next resource
    screen.cache.preload(res);
    return;
  }
  // We've gone through all queued resources
  // Check if we should reload early
  if (screen.reloadOnTimeout()) {
    return;
  }
  // Trigger another update to calculate a proper screen.endAt value
  screen.checkUpdates();
}

/**
 * Get next resource to preload from queue
 * @return {string|null} next resource url
 */
Preload.prototype.next = function() {
  for (var res in this.cache) {
    if (!this.cache.hasOwnProperty(res)) {
      continue;
    }

    if (this.isInPreloadQueue(res)) {
      return res;
    }
  }
  return null;
}


/**
 * Field class constructor
 * @param {jQuery.Object} $f field object
 */
function Field($f) {
  this.$field = $f;
  this.id = $f.attr('data-id');
  this.url = $f.attr('data-url');
  this.types = $f.attr('data-types').split(' ');
  this.randomOrder = $f.attr('data-random') == '1';
  this.canUpdate = this.url != null;
  this.contents = [];
  this.playCount = {};
  this.previous = null;
  this.current = null;
  this.next = null;
  this.timeout = null;
  this.endAt = null;
  this.stuck = false;
}

/**
 * Retrieves contents from backend for this field
 */
Field.prototype.fetchContents = function() {
  if (!this.canUpdate) {
    return;
  }

  var f = this;
  $.get(this.url, function(j) {
    if (j.success) {
      f.contents = j.next.map(function(c) {
        if (!f.playCount[c.id]) {
          f.playCount[c.id] = 0;
        }
        return new Content(c);
      });
      f.pickNextIfNecessary();
    } else {
      f.setError(j.message || 'Error');
    }
  });
}

/**
 * Display error in field text
 */
Field.prototype.setError = function(err) {
  this.display(err);
}

/**
 * Sort contents
 */
Field.prototype.sortContents = function() {
  this.contents = this.randomOrder ? this.sortContentsByPlayCountRandom() : this.sortContentsByPlayCountOrdered();
}

/**
 * Sort by play count this by random
 * @return {[]Content} sorted contents
 */
Field.prototype.sortContentsByPlayCountRandom = function() {
  var f = this;
  return this.contents.sort(function(a, b) {
    var pC = f.playCount[a.id] - f.playCount[b.id];
    return pC != 0 ? pC : Math.random() - 0.5;
  });
}

/**
 * Sort by play count this by content id
 * @return {[]Content} sorted contents
 */
Field.prototype.sortContentsByPlayCountOrdered = function() {
  var f = this;
  return this.contents.sort(function(a, b) {
    var pC = f.playCount[a.id] - f.playCount[b.id];
    return pC != 0 ? pC : a.id - b.id;
  });
}

/**
 * PickNext if no content currently displayed and content is available
 */
Field.prototype.pickNextIfNecessary = function() {
  if (!this.timeout) {
    this.pickNext();
  }
}

/**
 * Loop through field contents to pick next displayable content
 */
Field.prototype.pickNext = function() {
  // Keep track of true previous content
  if (this.current != null) {
    this.previous = this.current;
    this.playCount[this.current.id]++;
  }

  if (screen.reloadOnTimeout()) {
    // Currently trying to reload, we're past threshold: reload now
    return;
  }

  this.current = null;
  var previousData = this.previous && this.previous.data;

  this.next = this.pickContent(previousData) || this.pickContent(previousData, true);

  if (this.next) {
    // Overwrite field with newly picked content
    this.displayNext();
    this.stuck = false;
  } else {
    // I am stuck, don't know what to display
    this.stuck = true;
    // Check other fields for stuckiness state
    if (screen.isAllFieldsStuck() && !screen.cache.hasPreloadingContent(true)) {
      // Nothing to do. Give up, reload now
      screen.reloadNow();
    }
  }
}

/**
 * Loop through field contents for any displayable content
 * @param  {string}  previousData previous content data
 * @param  {boolean} anyUsable    ignore constraints
 * @return {Content}              random usable content
 */
Field.prototype.pickContent = function(previousData, anyUsable) {
  this.sortContents();

  for (var i = 0; i < this.contents.length; i++) {
    var c = this.contents[i];
    // Skip too long, not preloaded or empty content
    if (!c.canDisplay()) {
      continue;
    }

    if (anyUsable) {
      // Ignore repeat & same content constraints if necessary
      return c;
    }

    // Avoid repeat same content
    if (c.data == previousData) {
      // Not enough content, display anyway
      if (this.contents.length < 2) {
        return c;
      }
      continue;
    }

    // Avoid same content than already displayed on other fields
    if (screen.displaysData(c.data)) {
      // Not enough content, display anyway
      if (this.contents.length < 3) {
        return c;
      }
      continue;
    }

    // Nice content. Display it.
    return c;
  }
  return null;
}

/**
 * Setup next content for field and display it
 */
Field.prototype.displayNext = function() {
  var f = this;
  if (this.next && this.next.duration > 0) {
    this.current = this.next
    this.next = null;
    this.display(this.current.data);
    if (this.timeout) {
      clearTimeout(this.timeout);
    }
    this.endAt = Date.now() + this.current.duration;
    this.timeout = setTimeout(function() {
      f.pickNext();
    }, this.current.duration);
  }
}

/**
 * Display data in field HTML
 * @param {string} data
 */
Field.prototype.display = function(data) {
  this.$field.html(data);
  this.$field.show();
  var $bt = this.$field.find('.bigtext');
  // Only first data-min/max per field is respected
  var minPx = $bt.attr('data-min-px') || 4;
  var maxPx = $bt.attr('data-max-px') || 0;
  $bt.parent().textfill({
    minFontPixels: minPx,
    maxFontPixels: maxPx,
  });
}

// Global screen instance
var screen = null;

/**
 * jQuery.load event
 * Initialize Screen and Fields
 * Setup updates interval timeouts
 */
function onLoad() {
  screen = new Screen(updateScreenUrl);
  // Init
  $('.field').each(function() {
    var f = new Field($(this));
    screen.fields.push(f);
    f.fetchContents();
  });

  if (screen.url) {
    // Setup content updates loop
    setInterval(function() {
      for (var f in screen.fields) {
        if (screen.fields.hasOwnProperty(f)) {
          screen.fields[f].fetchContents();
        }
      }
      screen.checkUpdates();
    }, 60000); // 1 minute is enough alongside preload queue end trigger
    screen.checkUpdates();
  }
}

// Run
$(onLoad);


1			/** global: updateScreenUrl, navigator */
2
3			/**
4			* Screen class constructor
5			* @param {string} updateScreenUrl global screen update checks url
6			*/
7			function Screen(updateScreenUrl) {
8			this.fields = [];
9			this.url = updateScreenUrl;
10			this.lastChanges = null;
11			this.endAt = null;
12			this.nextUrl = null;
13			this.cache = new Preload(navigator.userAgent.toLowerCase().indexOf('kweb') == -1);
14			this.runOnce = false;
15			}
16
17			/**
18			* Ajax GET on updateScreenUrl to check lastChanges timestamp and reload if necessary
19			*/
20			Screen.prototype.checkUpdates = function() {
21			var s = this;
22			$.get(this.url, function(j) {
23			if (j.success) {
24			if (s.lastChanges == null) {
25			s.lastChanges = j.data.lastChanges;
26			} else if (s.lastChanges != j.data.lastChanges) {
27			// Remote screen updated, we should reload as soon as possible
28			s.nextUrl = null;
29			s.reloadIn(0);
30			return;
31			}
32
33			if (j.data.nextScreenUrl != null) {
34			// Setup next screen
35			s.nextUrl = j.data.nextScreenUrl;
36			if (j.data.duration > 0) {
37			s.reloadIn(j.data.duration * 1000);
38			} else {
39			s.runOnce = true;
40			}
41			}
42			} else if (j.message == 'Unauthorized') {
43			// Cookie/session gone bad, try to refresh with full screen reload
44			screen.reloadIn(0);
45			}
46			});
47			}
48
49			/**
50			* Start Screen reload procedure, checking for every field timeout
51			*/
52			Screen.prototype.reloadIn = function(minDuration) {
53			var endAt = Date.now() + minDuration;
54			if (this.endAt != null && this.endAt < endAt) {
55			// Already going to reload sooner than asked
56			return;
57			}
58
59			if (this.cache.hasPreloadingContent(true)) {
60			// Do not break preloading
61			return;
62			}
63
64			this.endAt = Date.now() + minDuration;
65			for (var i in this.fields) {
66			if (!this.fields.hasOwnProperty(i)) {
67			continue;
68			}
69			var f = this.fields[i];
70			if (f.timeout && f.endAt > this.endAt) {
71			// Always wait for content display end
72			this.endAt = f.endAt;
73			}
74			}
75
76			this.reloadOnTimeout();
77			}
78
79			/**
80			* Check if we're past the screen.endAt timeout and reload if necessary
81			* @return {boolean} going to reload
82			*/
83			Screen.prototype.reloadOnTimeout = function() {
84			if (screen.runOnce && screen.hasRanOnce() && !this.cache.hasPreloadingContent(true)) {
85			// Every content has been shown, reload
86			this.reloadNow();
87			return true;
88			}
89
90			if (this.endAt != null && Date.now() >= this.endAt) {
91			// No content to delay reload, do it now
92			this.reloadNow();
93			return true;
94			}
95
96			return false;
97			}
98
99			/**
100			* Actual Screen reload/change screen action
101			*/
102			Screen.prototype.reloadNow = function() {
103			if (this.nextUrl) {
104			window.location = this.nextUrl;
105			} else {
106			window.location.reload();
107			}
108			}
109
110			/**
111			* Check every field if contents have been all played at least once
112			* @return {Boolean} has every content been played
113			*/
114			Screen.prototype.hasRanOnce = function() {
115			for (var f in this.fields) {
116			if (!this.fields.hasOwnProperty(f)) {
117			continue;
118			}
119			f = this.fields[f];
120
121			for (var c in f.contents) {
122			if (!f.contents.hasOwnProperty(c)) {
123			continue;
124			}
125			c = f.contents[c];
126
127			if (f.playCount[c.id] < 1 && c.isPreloaded()) {
128			return false;
129			}
130			}
131			}
132
133			return true;
134			}
135
136			/**
137			* Check every field for content
138			* @param {Content} data
139			* @return {boolean} content is displayed
140			*/
141			Screen.prototype.displaysData = function(data) {
142			return this.fields.filter(function(field) {
143			return field.current && field.current.data == data;
144			}).length > 0;
145			}
146
147			/**
148			* Trigger pickNext on all fields
149			*/
150			Screen.prototype.newContentTrigger = function() {
151			for (var f in this.fields) {
152			if (!this.fields.hasOwnProperty(f)) {
153			continue;
154			}
155
156			this.fields[f].pickNextIfNecessary();
157			}
158			}
159
160			/**
161			* Loop through all fields for stuckiness state
162			* @return {boolean} are all fields stuck
163			*/
164			Screen.prototype.isAllFieldsStuck = function() {
165			for (var f in this.fields) {
166			if (!this.fields.hasOwnProperty(f)) {
167			continue;
168			}
169
170			if (!this.fields[f].stuck && this.fields[f].canUpdate) {
171			return false;
172			}
173			}
174
175			return true;
176			}
177
178
179			/**
180			* Content class constructor
181			* @param {array} c content attributes
182			*/
183			function Content(c) {
184			this.id = c.id;
185			this.data = c.data;
186			this.duration = c.duration * 1000;
187			this.type = c.type;
188			this.src = null;
189
190			if (this.shouldPreload()) {
191			this.queuePreload();
192			}
193			}
194
195			/**
196			* Check if content should be ajax preloaded
197			* @return {boolean} shoud preload
198			*/
199			Content.prototype.shouldPreload = function() {
200			return this.canPreload() && !this.isPreloadingOrQueued() && !this.isPreloaded();
201			}
202
203			/**
204			* Check if content has pre-loadable material
205			* @return {boolean} can preload
206			*/
207			Content.prototype.canPreload = function() {
208			return this.getResource() && this.type.search(/Video\|Image/) != -1;
209			}
210
211			/**
212			* Check if content is displayable (preloaded and not too long)
213			* @return {boolean} can display
214			*/
215			Content.prototype.canDisplay = function() {
216			return (screen.endAt == null \|\| Date.now() + this.duration < screen.endAt) && this.isPreloaded() && this.data;
217			}
218
219			/**
220			* Extract url from contant data
221			* @return {string} resource url
222			*/
223			Content.prototype.getResource = function() {
224			if (this.src) {
225			return this.src;
226			}
227			var srcMatch = this.data.match(/src="([^"]+)"/);
228			if (!srcMatch) {
229			// All preloadable content comes with a src attribute
230			return false;
231			}
232			var src = srcMatch[1];
233			if (src.indexOf('/') === 0) {
234			src = window.location.origin + src;
235			}
236			if (src.indexOf('http') !== 0) {
237			return false;
238			}
239			// Get rid of fragment
240			src = src.replace(/#.*/g, '');
241
242			this.src = src;
243			return src;
244			}
245
246			/**
247			* Set content cache status
248			* @param {string} state preload state
249			*/
250			Content.prototype.setPreloadState = function(state) {
251			screen.cache.setState(this.getResource(), state);
252			}
253
254			/**
255			* Check cache for preload status of content
256			* @return {boolean} is preloaded
257			*/
258			Content.prototype.isPreloaded = function() {
259			if (!this.canPreload()) {
260			return true;
261			}
262
263			return screen.cache.isPreloaded(this.getResource());
264			}
265
266			/**
267			* Check cache for in progress or future preloading
268			* @return {boolean} is preloading
269			*/
270			Content.prototype.isPreloadingOrQueued = function() {
271			return this.isPreloading() \|\| this.isInPreloadQueue();
272			}
273
274			/**
275			* Check cache for in progress preloading
276			* @return {boolean} is preloading
277			*/
278			Content.prototype.isPreloading = function() {
279			return screen.cache.isPreloading(this.getResource());
280			}
281
282			/**
283			* Check cache for queued preloading
284			* @return {boolean} is in preload queue
285			*/
286			Content.prototype.isInPreloadQueue = function() {
287			return screen.cache.isInPreloadQueue(this.getResource());
288			}
289
290			/**
291			* Call to preload content
292			*/
293			Content.prototype.preload = function() {
294			var src = this.getResource();
295			if (!src) {
296			return;
297			}
298
299			screen.cache.preload(src);
300			}
301
302			/**
303			* Preload content or add to preload queue
304			*/
305			Content.prototype.queuePreload = function() {
306			var src = this.getResource();
307			if (!src) {
308			return;
309			}
310
311			if (screen.cache.hasPreloadingContent(false)) {
312			this.setPreloadState(Preload.state.PRELOADING_QUEUE);
313			} else {
314			this.preload();
315			}
316			}
317
318
319			/**
320			* Preload class constructor
321			* Build cache map
322			* @param {boolean} isModernBrowser does browser support modern tags
323			*/
324			function Preload(isModernBrowser) {
325			this.cache = {};
326			if (isModernBrowser) {
327			this.preload = this.preloadPrefetch;
328			} else {
329			this.preload = this.preloadExternal;
330			}
331			}
332
333			/**
334			* Preload states
335			*/
336			Preload.state = {
337			ERR: -1,
338			WAIT_PRELOADER: 1,
339			PRELOADING: 2,
340			PRELOADING_QUEUE: 3,
341			OK: 4,
342			NO_CONTENT: 5,
343			HTTP_FAIL: 6,
344			}
345
346			/**
347			* Set resource cache state
348			* @param {string} res resource url
349			* @param {int} state preload state
350			*/
351			Preload.prototype.setState = function(res, state) {
352			this.cache[res] = state;
353			}
354
355			/**
356			* Check resource cache for readyness state
357			* @param {string} res resource url
358			* @return {boolean} is preloaded
359			*/
360			Preload.prototype.isPreloaded = function(res) {
361			return this.cache[res] === Preload.state.OK;
362			}
363
364			/**
365			* Check resource cache for preloading state
366			* @param {string} res resource url
367			* @return {boolean} is currently preloading
368			*/
369			Preload.prototype.isPreloading = function(res) {
370			return this.cache[res] === Preload.state.PRELOADING;
371			}
372
373			/**
374			* Check resource cache for queued preloading state
375			* @param {string} res resource url
376			* @return {boolean} is in preload queue
377			*/
378			Preload.prototype.isInPreloadQueue = function(res) {
379			return this.cache[res] === Preload.state.PRELOADING_QUEUE;
380			}
381
382			/**
383			* Check resource cache for queued preloading state during preloader pick phase
384			* @param {string} res resource url
385			* @return {boolean} is in preload queue
386			*/
387			Preload.prototype.isWaiting = function(res) {
388			return this.cache[res] === Preload.state.WAIT_PRELOADER;
389			}
390
391			/**
392			* Scan resource cache for preloading resources
393			* @param {boolean} withQueue also check preload queue
394			* @return {boolean} has any resource preloading/in preload queue
395			*/
396			Preload.prototype.hasPreloadingContent = function(withQueue) {
397			for (var res in this.cache) {
398			if (!this.cache.hasOwnProperty(res)) {
399			continue;
400			}
401
402			if (this.isPreloading(res) \|\| this.isWaiting(res) \|\| (withQueue && this.isInPreloadQueue(res))) {
403			return true;
404			}
405			}
406
407			return false;
408			}
409
410			/**
411			* Preload a resource
412			* Default implementation waits for preloader pick
413			* @param {string} res resource url
414			*/
415			Preload.prototype.preload = function(res) {
416			this.setState(res, Preload.state.WAIT_PRELOADER);
417			}
418
419			/**
420			* Triggered on preloader picked
421			* Restarts preload queue processing
422			*/
423			Preload.prototype.preloaderReady = function() {
424			for (var res in this.cache) {
425			if (!this.cache.hasOwnProperty(res)) {
426			continue;
427			}
428
429			if (this.isWaiting(res)) {
430			this.preload(res);
431			}
432			}
433			}
434
435			/**
436			* Preload a resource by calling external preloader
437			* @param {string} res resource url
438			*/
439			Preload.prototype.preloadExternal = function(res) {
440			this.setState(res, Preload.state.PRELOADING);
441			$.ajax("http://127.0.0.1:8089/pf?res=" + res).done(function(j) {
442			switch (j.state) {
443			case Preload.state.OK:
			0 ignored issues – show Bug introduced 2017-02-03 10:56 UTC by Report Bug Copy Issue Report The variable `Preload` seems to be never declared. If this is a global, consider adding a `/** global: Preload */` comment. This checks looks for references to variables that have not been declared. This is most likey a typographical error or a variable has been renamed. To learn more about declaring variables in Javascript, see the MDN. Loading history...
444			case Preload.state.NO_CONTENT:
445			screen.cache.setState(res, j.state);
446			screen.newContentTrigger();
447			break;
448			case Preload.state.HTTP_FAIL:
449			screen.cache.setState(res, j.state);
450			break;
451			case Preload.state.ERR:
452			screen.cache.setState(res, Preload.state.HTTP_FAIL);
453			break;
454			default:
455			return;
456			}
457			screen.cache.preloadNext();
458			}).fail(function() {
459			screen.cache.preload = screen.cache.preloadAjax;
460			screen.cache.preload(res);
461			});
462			}
463
464			/**
465			* Preload a resource by addinh a <link rel="prefetch"> tag
466			* @param {string} res resource url
467			*/
468			Preload.prototype.preloadPrefetch = function(res) {
469			this.setState(res, Preload.state.PRELOADING);
470			$('body').append(
471			$('<link>', {
472			rel: 'prefetch',
473			href: res
474			}).load(function() {
475			screen.cache.setState(res, Preload.state.OK);
476			screen.newContentTrigger();
477			screen.cache.preloadNext();
478			}).error(function() {
479			screen.cache.setState(res, Preload.state.HTTP_FAIL);
480			screen.cache.preloadNext();
481			})
482			);
483			}
484
485			/**
486			* Preload a resource by ajax get on the url
487			* Check HTTP return state to validate proper cache
488			* @param {string} res resource url
489			*/
490			Preload.prototype.preloadAjax = function(res) {
491			this.setState(res, Preload.state.PRELOADING);
492			$.ajax(res).done(function(data) {
493			// Preload success
494			if (data === '') {
495			screen.cache.setState(res, Preload.state.NO_CONTENT);
496			} else {
497			screen.cache.setState(res, Preload.state.OK);
498			}
499			screen.newContentTrigger();
500			}).fail(function() {
501			// Preload failure
502			screen.cache.setState(res, Preload.state.HTTP_FAIL);
503			}).always(function() {
504			screen.cache.preloadNext();
505			});
506			}
507
508			/**
509			* Try to preload next resource or trigger preload end event
510			*/
511			Preload.prototype.preloadNext = function() {
512			var res = screen.cache.next();
513			if (res) {
514			// Preload ended, next resource
515			screen.cache.preload(res);
516			return;
517			}
518			// We've gone through all queued resources
519			// Check if we should reload early
520			if (screen.reloadOnTimeout()) {
521			return;
522			}
523			// Trigger another update to calculate a proper screen.endAt value
524			screen.checkUpdates();
525			}
526
527			/**
528			* Get next resource to preload from queue
529			* @return {string\|null} next resource url
530			*/
531			Preload.prototype.next = function() {
532			for (var res in this.cache) {
533			if (!this.cache.hasOwnProperty(res)) {
534			continue;
535			}
536
537			if (this.isInPreloadQueue(res)) {
538			return res;
539			}
540			}
541			return null;
542			}
543
544
545			/**
546			* Field class constructor
547			* @param {jQuery.Object} $f field object
548			*/
549			function Field($f) {
550			this.$field = $f;
551			this.id = $f.attr('data-id');
552			this.url = $f.attr('data-url');
553			this.types = $f.attr('data-types').split(' ');
554			this.randomOrder = $f.attr('data-random') == '1';
555			this.canUpdate = this.url != null;
556			this.contents = [];
557			this.playCount = {};
558			this.previous = null;
559			this.current = null;
560			this.next = null;
561			this.timeout = null;
562			this.endAt = null;
563			this.stuck = false;
564			}
565
566			/**
567			* Retrieves contents from backend for this field
568			*/
569			Field.prototype.fetchContents = function() {
570			if (!this.canUpdate) {
571			return;
572			}
573
574			var f = this;
575			$.get(this.url, function(j) {
576			if (j.success) {
577			f.contents = j.next.map(function(c) {
578			if (!f.playCount[c.id]) {
579			f.playCount[c.id] = 0;
580			}
581			return new Content(c);
582			});
583			f.pickNextIfNecessary();
584			} else {
585			f.setError(j.message \|\| 'Error');
586			}
587			});
588			}
589
590			/**
591			* Display error in field text
592			*/
593			Field.prototype.setError = function(err) {
594			this.display(err);
595			}
596
597			/**
598			* Sort contents
599			*/
600			Field.prototype.sortContents = function() {
601			this.contents = this.randomOrder ? this.sortContentsByPlayCountRandom() : this.sortContentsByPlayCountOrdered();
602			}
603
604			/**
605			* Sort by play count this by random
606			* @return {[]Content} sorted contents
607			*/
608			Field.prototype.sortContentsByPlayCountRandom = function() {
609			var f = this;
610			return this.contents.sort(function(a, b) {
611			var pC = f.playCount[a.id] - f.playCount[b.id];
612			return pC != 0 ? pC : Math.random() - 0.5;
613			});
614			}
615
616			/**
617			* Sort by play count this by content id
618			* @return {[]Content} sorted contents
619			*/
620			Field.prototype.sortContentsByPlayCountOrdered = function() {
621			var f = this;
622			return this.contents.sort(function(a, b) {
623			var pC = f.playCount[a.id] - f.playCount[b.id];
624			return pC != 0 ? pC : a.id - b.id;
625			});
626			}
627
628			/**
629			* PickNext if no content currently displayed and content is available
630			*/
631			Field.prototype.pickNextIfNecessary = function() {
632			if (!this.timeout) {
633			this.pickNext();
634			}
635			}
636
637			/**
638			* Loop through field contents to pick next displayable content
639			*/
640			Field.prototype.pickNext = function() {
641			// Keep track of true previous content
642			if (this.current != null) {
643			this.previous = this.current;
644			this.playCount[this.current.id]++;
645			}
646
647			if (screen.reloadOnTimeout()) {
648			// Currently trying to reload, we're past threshold: reload now
649			return;
650			}
651
652			this.current = null;
653			var previousData = this.previous && this.previous.data;
654
655			this.next = this.pickContent(previousData) \|\| this.pickContent(previousData, true);
656
657			if (this.next) {
658			// Overwrite field with newly picked content
659			this.displayNext();
660			this.stuck = false;
661			} else {
662			// I am stuck, don't know what to display
663			this.stuck = true;
664			// Check other fields for stuckiness state
665			if (screen.isAllFieldsStuck() && !screen.cache.hasPreloadingContent(true)) {
666			// Nothing to do. Give up, reload now
667			screen.reloadNow();
668			}
669			}
670			}
671
672			/**
673			* Loop through field contents for any displayable content
674			* @param {string} previousData previous content data
675			* @param {boolean} anyUsable ignore constraints
676			* @return {Content} random usable content
677			*/
678			Field.prototype.pickContent = function(previousData, anyUsable) {
679			this.sortContents();
680
681			for (var i = 0; i < this.contents.length; i++) {
682			var c = this.contents[i];
683			// Skip too long, not preloaded or empty content
684			if (!c.canDisplay()) {
685			continue;
686			}
687
688			if (anyUsable) {
689			// Ignore repeat & same content constraints if necessary
690			return c;
691			}
692
693			// Avoid repeat same content
694			if (c.data == previousData) {
695			// Not enough content, display anyway
696			if (this.contents.length < 2) {
697			return c;
698			}
699			continue;
700			}
701
702			// Avoid same content than already displayed on other fields
703			if (screen.displaysData(c.data)) {
704			// Not enough content, display anyway
705			if (this.contents.length < 3) {
706			return c;
707			}
708			continue;
709			}
710
711			// Nice content. Display it.
712			return c;
713			}
714			return null;
715			}
716
717			/**
718			* Setup next content for field and display it
719			*/
720			Field.prototype.displayNext = function() {
721			var f = this;
722			if (this.next && this.next.duration > 0) {
723			this.current = this.next
724			this.next = null;
725			this.display(this.current.data);
726			if (this.timeout) {
727			clearTimeout(this.timeout);
728			}
729			this.endAt = Date.now() + this.current.duration;
730			this.timeout = setTimeout(function() {
731			f.pickNext();
732			}, this.current.duration);
733			}
734			}
735
736			/**
737			* Display data in field HTML
738			* @param {string} data
739			*/
740			Field.prototype.display = function(data) {
741			this.$field.html(data);
742			this.$field.show();
743			var $bt = this.$field.find('.bigtext');
744			// Only first data-min/max per field is respected
745			var minPx = $bt.attr('data-min-px') \|\| 4;
746			var maxPx = $bt.attr('data-max-px') \|\| 0;
747			$bt.parent().textfill({
748			minFontPixels: minPx,
749			maxFontPixels: maxPx,
750			});
751			}
752
753			// Global screen instance
754			var screen = null;
755
756			/**
757			* jQuery.load event
758			* Initialize Screen and Fields
759			* Setup updates interval timeouts
760			*/
761			function onLoad() {
762			screen = new Screen(updateScreenUrl);
763			// Init
764			$('.field').each(function() {
765			var f = new Field($(this));
766			screen.fields.push(f);
767			f.fetchContents();
768			});
769
770			if (screen.url) {
771			// Setup content updates loop
772			setInterval(function() {
773			for (var f in screen.fields) {
774			if (screen.fields.hasOwnProperty(f)) {
775			screen.fields[f].fetchContents();
776			}
777			}
778			screen.checkUpdates();
779			}, 60000); // 1 minute is enough alongside preload queue end trigger
780			screen.checkUpdates();
781			}
782			}
783
784			// Run
785			$(onLoad);
786

jf-guillou / lcds

Push — master ( 9a2843...3c69ee )

Field.pickContent C

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