Refactor page switching into more django-like flexible architecture

diff --git a/www/index.html b/www/index.html
index 06be484..49a9be3 100644 (file)
--- a/www/index.html
+++ b/www/index.html
@@ -58,7 +58,7 @@
   <div id="items" style="display:none">
   </div>
 
-  <div id="welcome">
+  <div id="welcome" style="display:none">
 
   <div id="latest">
     <h2>Latest posts</h2>

diff --git a/www/js/blerg.js b/www/js/blerg.js
index b0bc38f..d0135b8 100644 (file)
--- a/www/js/blerg.js
+++ b/www/js/blerg.js
@@ -5,10 +5,10 @@
 // Config
 var baseURL = '';
 var recordTemplate = new Template(
-    '<div class="record">#{data}<div class="info">Posted #{date}. <a href="/\##{author}/#{record}">[permalink]</a> <a href="#" onclick="postPopup(\'@#{author}/#{record}: \'); return false">[reply]</a></div></div>'
+    '<div class="record">#{data}<div class="info">Posted #{date}. <a href="/\##{author}/#{record}" onclick="return qlink()">[permalink]</a> <a href="#" onclick="postPopup(\'@#{author}/#{record}: \'); return false">[reply]</a></div></div>'
 );
 var tagRecordTemplate = new Template(
-    '<div class="record">#{data}<div class="info">Posted by <a class="author ref" href="/\##{author}" onclick="return qlink()">@#{author}</a> on #{date}. <a href="/\##{author}/#{record}">[permalink]</a> <a href="#" onclick="postPopup(\'@#{author}/#{record}: \'); return false">[reply]</a></div></div>'
+    '<div class="record">#{data}<div class="info">Posted by <a class="author ref" href="/\##{author}" onclick="return qlink()">@#{author}</a> on #{date}. <a href="/\##{author}/#{record}" onclick="return qlink()">[permalink]</a> <a href="#" onclick="postPopup(\'@#{author}/#{record}: \'); return false">[reply]</a></div></div>'
 );
 var latestRecordsTemplate = new Template(
     '<div class="record"><a class="author ref" href="/\##{author}" onclick="return qlink()">@#{author}</a> #{data}</div>'
@@ -127,13 +127,25 @@ LoginStatus.prototype.post = function(msg) {
 // Base object for paged data
 function Pager() {
     this.itemsPerPage = 10;
-}
-
-Pager.prototype.initPager = function() {
     this.itemCache = new Hash();
     this.pageStart = null;
 }
 
+Pager.prototype.updateState = function(m) {
+    return false;
+}
+
+Pager.prototype.show = function() {
+    items.show();
+}
+
+Pager.prototype.hide = function() {
+    items.hide();
+    items.update();
+    $('newer_link').hide();
+    $('older_link').hide();
+}
+
 Pager.prototype.olderPage = function() {
     if (this.pageStart >= this.itemsPerPage) {
         qlink(this.baseFrag + '/p' + (this.pageStart - this.itemsPerPage));
@@ -213,24 +225,52 @@ Pager.prototype.loadItems = function(from, to, continuation) { }
 
 
 // Object to render user pages
-function User(username) {
-    this.initPager();
-    this.username = username;
-    this.baseFrag = username;
+function User(m) {
+    Pager.call(this);
+    this.username = m[1];
+    this.baseFrag = m[1];
+    this.permalink = (m[2] != 'p');
+    this.pageStart = parseInt(m[3]);
 }
 User.prototype = new Pager();
 User.prototype.constructor = User;
 
+User.prototype.updateState = function(m) {
+    if (m[1] != this.username)
+        return false;
+    
+    this.permalink = (m[2] != 'p');
+    this.pageStart = parseInt(m[3]);
+    this.show();
+
+    return true;
+}
+
 User.prototype.show = function() {
+    Pager.prototype.show.call(this);
+
     $$('[name=section]').each(function(v) { v.update(' @' + this.username) }.bind(this));
-    $('welcome').hide();
-    items.show();
     $('rss').show();
     $('rsslink').href = '/rss/' + this.username;
     $$('[name=user.reflink]').each(function(e) {
         e.href = '/#/ref/' + this.username;
     }.bind(this));
     $('usercontrols').show();
+
+    if (this.permalink && this.pageStart) {
+        this.showRecord(this.pageStart);
+    } else if (this.pageStart) {
+        this.showPageAt(this.pageStart);
+    } else {
+        this.reload();
+    }
+}
+
+User.prototype.hide = function() {
+    Pager.prototype.hide.call(this);
+    $('signup').hide();
+    $('rss').hide();
+    $('usercontrols').hide();
 }
 
 User.prototype.reload = function() {
@@ -261,11 +301,10 @@ User.prototype.reload = function() {
     new Ajax.Request(baseURL + '/info/' + this.username, {
         method: 'get',
         onSuccess: function(r) {
-            var j = r.responseText.evalJSON();
-            if (j) {
-                this.itemCount = parseInt(j.record_count);
-                if (!this.pageStart)
-                    this.showPageAt(this.itemCount - 1);
+            var response = r.responseText.evalJSON();
+            if (response) {
+                this.itemCount = parseInt(response.record_count);
+                this.showPageAt(this.itemCount - 1);
             }
         }.bind(this)
     });
@@ -404,27 +443,28 @@ function displayError(msg) {
 
 
 // Object for browsing tags
-function Tag(type, tag) {
-    this.initPager();
-    this.type = type;
-    this.tag = tag;
+function Tag(m) {
+    Pager.call(this);
+    this.type = m[1];
+    this.tag = m[2];
+    this.pageStart = parseInt(m[3]);
 
     var url = baseURL + "/tag/";
-    switch(type) {
+    switch(this.type) {
     case 'tag':
         //url += '%23';
         url += 'H';  // apache is eating the hash, even encoded.  Probably a security feature.
-        this.baseFrag = '/tag/' + tag;
+        this.baseFrag = '/tag/' + this.tag;
         break;
     case 'ref':
         url += '%40';
-        this.baseFrag = '/ref/' + tag;
+        this.baseFrag = '/ref/' + this.tag;
         break;
     default:
-        alert('Invalid tag type: ' + type);
+        alert('Invalid tag type: ' + this.type);
         return;
     }
-    url += tag;
+    url += this.tag;
 
     new Ajax.Request(url, {
         method: 'get',
@@ -437,7 +477,8 @@ function Tag(type, tag) {
                     mangleRecord(v, tagRecordTemplate)
                 });
                 this.addItems(j);
-                this.pageStart = j.length - 1;
+                if (!this.pageStart)
+                    this.pageStart = j.length - 1;
                 this.itemCount = j.length;
             }
             this.displayItems();
@@ -451,27 +492,33 @@ function Tag(type, tag) {
 Tag.prototype = new Pager();
 Tag.prototype.constructor = Tag;
 
+Tag.prototype.updateState = function(m) {
+    if (this.type != m[1] || this.tag != m[2])
+        return false;
+
+    this.pageStart = parseInt(m[3]) || this.itemCount - 1;
+    this.displayItems();
+
+    return true;
+}
+
 Tag.prototype.show = function() {
+    Pager.prototype.show.call(this);
+
     var ctype = {ref: '@', tag: '#'}[this.type];
 
     $$('[name=section]').each(function(v) {
         v.update(' about ' + ctype + this.tag);
     }.bind(this));
-    $('welcome').hide();
-    $('post').hide();
-    $('older_link').hide();
-    $('newer_link').hide();
-    $('rss').hide();
-    items.show();
-    $('usercontrols').hide();
 }
 
 
 // Pager for browsing subscription feeds
-function Feed() {
-    this.initPager();
+function Feed(m) {
+    Pager.call(this);
     this.username = loginStatus.username;
     this.baseFrag = '/feed';
+    this.pageStart = parseInt(m[1]);
 
     new Ajax.Request(baseURL + '/feed', {
         method: 'post',
@@ -487,7 +534,8 @@ function Feed() {
                     mangleRecord(v, tagRecordTemplate)
                 });
                 this.addItems(response);
-                this.pageStart = response.length - 1;
+                if (!this.pageStart)
+                    this.pageStart = response.length - 1;
                 this.itemCount = response.length;
             }
             this.displayItems();
@@ -500,17 +548,18 @@ function Feed() {
 Feed.prototype = new Pager();
 Feed.prototype.constructor = Feed;
 
+Feed.prototype.updateState = function(m) {
+    this.pageStart = parseInt(m[1]) || this.itemCount - 1;
+    this.displayItems();
+
+    return true;
+}
+
 Feed.prototype.show = function() {
+    Pager.prototype.show.call(this);
     $$('[name=section]').each(function(v) {
         v.update(' ' + loginStatus.username + "'s spycam");
     }.bind(this));
-    $('welcome').hide();
-    $('post').hide();
-    $('older_link').hide();
-    $('newer_link').hide();
-    $('rss').hide();
-    items.show();
-    $('usercontrols').hide();
 }
 
 
@@ -554,7 +603,7 @@ function signup() {
 
 function signup_cancel() {
     $('signup').hide();
-    hashSwitch();
+    urlSwitch();
 }
 
 function subscribe() {
@@ -704,76 +753,75 @@ function qlink(loc) {
         // Bogus qlink
         return;
     }
-    hashSwitch();
+    lastHash = location.hash;
+    urlSwitch();
     return false;
 }
 
-function hashSwitch() {
-    var m;
+function Welcome() {
+    loadLatest();
+}
+
+Welcome.prototype.show = function() {
+    $$('[name=section]').each(function(v) { v.update('Welcome') });
+    $('welcome').show();
+}
+
+Welcome.prototype.hide = function() {
     stopTicker();
-    if (m = location.search.match(/^\?post\/([^/]+)\/(.+)/)) {
-        $('post').show();
-        $('post.content').value = '[' + decodeURIComponent(m[1]).replace(']','').replace('[','') + '](' + decodeURIComponent(m[2]) + ')';
-    } else if (m = location.hash.match(/^#\/(ref|tag)\/([A-Za-z0-9_-]+)(?:\/p(\d+))?$/)) {
-        if (!currentPager || !(currentPager instanceof Tag) || currentPager.type != m[1] || currentPager.tag != m[2])
-            currentPager = new Tag(m[1], m[2]);
-        currentPager.show();
+    $('welcome').hide();
+}
 
-        if (m[3]) {
-            var r = parseInt(m[3]);
-            currentPager.showPageAt(r);
-        } else {
-            currentPager.showPageAt(currentPager.itemCount - 1);
-        }
-    } else if (m = location.hash.match(/^#\/feed(?:\/p(\d+))?$/)) {
-        if (loginStatus.loggedIn) {
-            if (!currentPager || !(currentPager instanceof Feed) || currentPager.username != loginStatus.username)
-                currentPager = new Feed();
-            currentPager.show();
-            if (m[3]) {
-                var r = parseInt(m[3]);
-                currentPager.showPageAt(r);
-            } else {
-                currentPager.showPageAt(currentPager.itemCount - 1);
-            }
-        } else {
-            location.href = baseURL;
-        }
-    } else if (m = location.hash.match(/^#([A-Za-z0-9_-]+)(?:\/(p)?(\d+))?$/)) {
-        if (!currentPager || !(currentPager instanceof User) || currentPager.username != m[1])
-            currentPager = new User(m[1]);
-        currentPager.show();
-        loginStatus.update();
+function ExternalURLPost(m) {
+    this.title = decodeURIComponent(m[1]).replace(']','').replace('[','');
+    this.url = decodeURIComponent(m[2]);
+}
 
-        if (m[3]) {
-            var r = parseInt(m[3]);
-            if (m[2] == 'p') {
-                currentPager.showPageAt(r);
-            } else {
-                currentPager.showRecord(r);
-            }
-        } else {
-            currentPager.reload();
+ExternalURLPost.prototype.show = function() {
+    $('post.content').value = '[' + this.title + '](' + this.url + ')';
+    $('post').show();
+}
+
+var urlmap = [
+    ['search', /^\?post\/([^/]+)\/(.+)/, ExternalURLPost],
+    ['hash',   /^#\/(ref|tag)\/([A-Za-z0-9_-]+)(?:\/p(\d+))?$/, Tag],
+    ['hash',   /^#\/feed(?:\/p(\d+))?$/, Feed],
+    ['hash',   /^#([A-Za-z0-9_-]+)(?:\/(p)?(\d+))?$/, User]
+];
+
+function urlSwitch() {
+    var m;
+    var pageconstructor;
+
+    for (var i = 0; i < urlmap.length; i++) {
+        if (m = location[urlmap[i][0]].match(urlmap[i][1])) {
+            pageconstructor = urlmap[i][2];
+            break;
         }
-    } else {
-        $$('[name=section]').each(function(v) { v.update('Welcome') });
-        $('signup').hide();
-        items.update();
-        items.hide();
-        $('newer_link').hide();
-        $('older_link').hide();
-        $('welcome').show();
-        $('rss').hide();
-        $('usercontrols').hide();
-        loadLatest();
     }
+    if (i == urlmap.length)
+        pageconstructor = Welcome;
+
+    if (currentPager && currentPager instanceof pageconstructor) {
+        // updateState returns true if the state has been successfully updated.
+        // Otherwise, we continue and create a new instance.
+        if (currentPager.updateState(m))
+            return;
+    }
+
+    if (currentPager && currentPager.hide)
+        currentPager.hide();
+
+    currentPager = new pageconstructor(m);
+    if (currentPager.show)
+        currentPager.show();
 }
 
 var lastHash;
 function hashCheck() {
     if (location.hash != lastHash) {
         lastHash = location.hash;
-        hashSwitch();
+        urlSwitch();
     }
 }
 
@@ -782,7 +830,7 @@ function init() {
     loginStatus = new LoginStatus();
 
     lastHash = location.hash;
-    hashSwitch();
+    urlSwitch();
 
     setInterval(hashCheck, 250);