Show warning in editor when local draft is out of date

Fixes #41

less/pad.less

@@ -361,6 +361,24 @@ body#pad {
     z-index: 10;
 }
 
+body#pad .alert {
+	position: fixed;
+	bottom: 0.25em;
+	left: 2em;
+	right: 2em;
+	font-size: 1.1em;
+
+	&#edited-elsewhere {
+		&.hidden {
+			display: none;
+		}
+
+		a {
+			font-weight: bold;
+		}
+	}
+}
+
 @media all and (max-height: 500px) {
 	body#pad {
 		textarea {
@@ -425,6 +443,10 @@ body#pad {
 			padding-left: 10%;
 			padding-right: 10%;
 		}
+		.alert {
+			left: 10%;
+			right: 10%;
+		}
 	}
 }
 @media all and (min-width: 60em) {
@@ -433,6 +455,10 @@ body#pad {
 			padding-left: 15%;
 			padding-right: 15%;
 		}
+		.alert {
+			left: 15%;
+			right: 15%;
+		}
 	}
 }
 @media all and (min-width: 70em) {
@@ -441,6 +467,10 @@ body#pad {
 			padding-left: 20%;
 			padding-right: 20%;
 		}
+		.alert {
+			left: 20%;
+			right: 20%;
+		}
 	}
 }
 @media all and (min-width: 85em) {
@@ -449,6 +479,10 @@ body#pad {
 			padding-left: 25%;
 			padding-right: 25%;
 		}
+		.alert {
+			left: 25%;
+			right: 25%;
+		}
 	}
 }
 @media all and (min-width: 105em) {
@@ -457,6 +491,10 @@ body#pad {
 			padding-left: 30%;
 			padding-right: 30%;
 		}
+		.alert {
+			left: 30%;
+			right: 30%;
+		}
 	}
 }
 @media (pointer: coarse) {

posts.go

@@ -135,6 +135,7 @@ type (
 		Views        int64
 		Font         string
 		Created      time.Time
+		Updated      time.Time
 		IsRTL        sql.NullBool
 		Language     sql.NullString
 		OwnerID      int64
@@ -1240,9 +1241,9 @@ func getRawPost(app *App, friendlyID string) *RawPost {
 	var isRTL sql.NullBool
 	var lang sql.NullString
 	var ownerID sql.NullInt64
-	var created time.Time
+	var created, updated time.Time
 
-	err := app.db.QueryRow("SELECT title, content, text_appearance, language, rtl, created, owner_id FROM posts WHERE id = ?", friendlyID).Scan(&title, &content, &font, &lang, &isRTL, &created, &ownerID)
+	err := app.db.QueryRow("SELECT title, content, text_appearance, language, rtl, created, updated, owner_id FROM posts WHERE id = ?", friendlyID).Scan(&title, &content, &font, &lang, &isRTL, &created, &updated, &ownerID)
 	switch {
 	case err == sql.ErrNoRows:
 		return &RawPost{Content: "", Found: false, Gone: false}
@@ -1250,7 +1251,7 @@ func getRawPost(app *App, friendlyID string) *RawPost {
 		return &RawPost{Content: "", Found: true, Gone: false}
 	}
 
-	return &RawPost{Title: title, Content: content, Font: font, Created: created, IsRTL: isRTL, Language: lang, OwnerID: ownerID.Int64, Found: true, Gone: content == ""}
+	return &RawPost{Title: title, Content: content, Font: font, Created: created, Updated: updated, IsRTL: isRTL, Language: lang, OwnerID: ownerID.Int64, Found: true, Gone: content == ""}
 
 }
 
@@ -1259,15 +1260,15 @@ func getRawCollectionPost(app *App, slug, collAlias string) *RawPost {
 	var id, title, content, font string
 	var isRTL sql.NullBool
 	var lang sql.NullString
-	var created time.Time
+	var created, updated time.Time
 	var ownerID null.Int
 	var views int64
 	var err error
 
 	if app.cfg.App.SingleUser {
-		err = app.db.QueryRow("SELECT id, title, content, text_appearance, language, rtl, view_count, created, owner_id FROM posts WHERE slug = ? AND collection_id = 1", slug).Scan(&id, &title, &content, &font, &lang, &isRTL, &views, &created, &ownerID)
+		err = app.db.QueryRow("SELECT id, title, content, text_appearance, language, rtl, view_count, created, updated, owner_id FROM posts WHERE slug = ? AND collection_id = 1", slug).Scan(&id, &title, &content, &font, &lang, &isRTL, &views, &created, &updated, &ownerID)
 	} else {
-		err = app.db.QueryRow("SELECT id, title, content, text_appearance, language, rtl, view_count, created, owner_id FROM posts WHERE slug = ? AND collection_id = (SELECT id FROM collections WHERE alias = ?)", slug, collAlias).Scan(&id, &title, &content, &font, &lang, &isRTL, &views, &created, &ownerID)
+		err = app.db.QueryRow("SELECT id, title, content, text_appearance, language, rtl, view_count, created, updated, owner_id FROM posts WHERE slug = ? AND collection_id = (SELECT id FROM collections WHERE alias = ?)", slug, collAlias).Scan(&id, &title, &content, &font, &lang, &isRTL, &views, &created, &updated, &ownerID)
 	}
 	switch {
 	case err == sql.ErrNoRows:
@@ -1283,6 +1284,7 @@ func getRawCollectionPost(app *App, slug, collAlias string) *RawPost {
 		Content:  content,
 		Font:     font,
 		Created:  created,
+		Updated:  updated,
 		IsRTL:    isRTL,
 		Language: lang,
 		OwnerID:  ownerID.Int64,
@@ -1543,6 +1545,13 @@ func (rp *RawPost) Created8601() string {
 	return rp.Created.Format("2006-01-02T15:04:05Z")
 }
 
+func (rp *RawPost) Updated8601() string {
+	if rp.Updated.IsZero() {
+		return ""
+	}
+	return rp.Updated.Format("2006-01-02T15:04:05Z")
+}
+
 var imageURLRegex = regexp.MustCompile(`(?i)[^ ]+\.(gif|png|jpg|jpeg|image)$`)
 
 func (p *Post) extractImages() {

static/js/h.js

@@ -116,13 +116,27 @@ var H = {
 	save: function($el, key) {
 		localStorage.setItem(key, $el.el.value);
 	},
-	load: function($el, key, onlyLoadPopulated) {
+	load: function($el, key, onlyLoadPopulated, postUpdated) {
 		var val = localStorage.getItem(key);
 		if (onlyLoadPopulated && val == null) {
 			// Do nothing
-			return;
+			return true;
 		}
 		$el.el.value = val;
+		if (postUpdated != null) {
+			var lastLocalPublishStr = localStorage.getItem(key+'-published');
+			if (lastLocalPublishStr != null && lastLocalPublishStr != '') {
+				try {
+					var lastLocalPublish = new Date(lastLocalPublishStr);
+					if (postUpdated > lastLocalPublish) {
+						return false;
+					}
+				} catch (e) {
+					console.error("unable to parse draft updated time");
+				}
+			}
+		}
+		return true;
 	},
 	set: function(key, value) {
 		localStorage.setItem(key, value);

templates/bare.tmpl

@@ -17,6 +17,8 @@
 
 {{end}}{{.Post.Content}}</textarea>
 
+		<div class="alert success hidden" id="edited-elsewhere">This post has been updated elsewhere since you last published! <a href="#" id="erase-edit">Delete draft and reload</a>.</div>
+		
 		<header id="tools">
 			<div id="clip">
 				{{if not .SingleUser}}<h1>{{if .Chorus}}<a href="/" title="Home">{{else}}<a href="/me/c/" title="View blogs">{{end}}{{.SiteName}}</a></h1>{{end}}
@@ -36,6 +38,7 @@
 		<script>
 		var $writer = H.getEl('writer');
 		var $btnPublish = H.getEl('publish');
+		var $btnEraseEdit = H.getEl('edited-elsewhere');
 		var $wc = H.getEl("wc");
 		var updateWordCount = function() {
 			var words = 0;
@@ -58,7 +61,17 @@
 		};
 		{{if .Post.Id}}var draftDoc = 'draft{{.Post.Id}}';
 		var origDoc = '{{.Post.Content}}';{{else}}var draftDoc = 'lastDoc';{{end}}
-		H.load($writer, draftDoc, true);
+		var updatedStr = '{{.Post.Updated8601}}';
+		var updated = null;
+		if (updatedStr != '') {
+			updated = new Date(updatedStr);
+		}
+		var ok = H.load($writer, draftDoc, true, updated);
+		if (!ok) {
+			// Show "edited elsewhere" warning
+			$btnEraseEdit.el.classList.remove('hidden');
+		}
+		var defaultTimeSet = false;
 		updateWordCount();
 		
 		var typingTimer;
@@ -130,6 +143,7 @@
 						data = JSON.parse(http.responseText);
 						id = data.data.id;
 						nextURL = '{{if .SingleUser}}/d{{end}}/'+id;
+						localStorage.setItem('draft'+id+'-published', new Date().toISOString());
 
 						{{ if not .Post.Id }}
 							// Post created
@@ -198,6 +212,13 @@
 				publish(content, selectedFont);
 			}
 		});
+		H.getEl('erase-edit').on('click', function(e) {
+			e.preventDefault();
+			H.remove(draftDoc);
+			H.remove(draftDoc+'-published');
+			justPublished = true; // Block auto-save
+			location.reload();
+		});
 
 		WebFontConfig = {
 			custom: { families: [ 'Lora:400,700:latin' ], urls: [ '/css/fonts.css' ] }
@@ -207,12 +228,20 @@
 		var doneTyping = function() {
 			if (draftDoc == 'lastDoc' || $writer.el.value != origDoc) {
 				H.save($writer, draftDoc);
+				if (!defaultTimeSet) {
+					var lastLocalPublishStr = localStorage.getItem(draftDoc+'-published');
+					if (lastLocalPublishStr == null || lastLocalPublishStr == '') {
+						localStorage.setItem(draftDoc+'-published', updatedStr);
+					}
+					defaultTimeSet = true;
+				}
 				updateWordCount();
 			}
 		};
 		window.addEventListener('beforeunload', function(e) {
 			if (draftDoc != 'lastDoc' && $writer.el.value == origDoc) {
 				H.remove(draftDoc);
+				H.remove(draftDoc+'-published');
 			} else if (!justPublished) {
 				doneTyping();
 			}

templates/pad.tmpl

@@ -17,6 +17,8 @@
 
 {{end}}{{.Post.Content}}</textarea>
 
+		<div class="alert success hidden" id="edited-elsewhere">This post has been updated elsewhere since you last published! <a href="#" id="erase-edit">Delete draft and reload</a>.</div>
+		
 		<header id="tools">
 			<div id="clip">
 				{{if not .SingleUser}}<h1><a href="/me/c/" title="View blogs"><img class="ic-24dp" src="/img/ic_blogs_dark@2x.png" /></a></h1>{{end}}
@@ -88,6 +90,7 @@
 		}
 		var $writer = H.getEl('writer');
 		var $btnPublish = H.getEl('publish');
+		var $btnEraseEdit = H.getEl('edited-elsewhere');
 		var $wc = H.getEl("wc");
 		var updateWordCount = function() {
 			var words = 0;
@@ -110,7 +113,17 @@
 		};
 		{{if .Post.Id}}var draftDoc = 'draft{{.Post.Id}}';
 		var origDoc = '{{.Post.Content}}';{{else}}var draftDoc = 'lastDoc';{{end}}
-		H.load($writer, draftDoc, true);
+		var updatedStr = '{{.Post.Updated8601}}';
+		var updated = null;
+		if (updatedStr != '') {
+			updated = new Date(updatedStr);
+		}
+		var ok = H.load($writer, draftDoc, true, updated);
+		if (!ok) {
+			// Show "edited elsewhere" warning
+			$btnEraseEdit.el.classList.remove('hidden');
+		}
+		var defaultTimeSet = false;
 		updateWordCount();
 		
 		var typingTimer;
@@ -190,6 +203,7 @@
 						data = JSON.parse(http.responseText);
 						id = data.data.id;
 						nextURL = '{{if .SingleUser}}/d{{end}}/'+id;
+						localStorage.setItem('draft'+id+'-published', new Date().toISOString());
 
 						{{ if not .Post.Id }}
 							// Post created
@@ -258,6 +272,13 @@
 				publish(content, selectedFont);
 			}
 		});
+		H.getEl('erase-edit').on('click', function(e) {
+			e.preventDefault();
+			H.remove(draftDoc);
+			H.remove(draftDoc+'-published');
+			justPublished = true; // Block auto-save
+			location.reload();
+		});
 
 		H.getEl('toggle-theme').on('click', function(e) {
 			e.preventDefault();
@@ -338,12 +359,20 @@
 		var doneTyping = function() {
 			if (draftDoc == 'lastDoc' || $writer.el.value != origDoc) {
 				H.save($writer, draftDoc);
+				if (!defaultTimeSet) {
+					var lastLocalPublishStr = localStorage.getItem(draftDoc+'-published');
+					if (lastLocalPublishStr == null || lastLocalPublishStr == '') {
+						localStorage.setItem(draftDoc+'-published', updatedStr);
+					}
+					defaultTimeSet = true;
+				}
 				updateWordCount();
 			}
 		};
 		window.addEventListener('beforeunload', function(e) {
 			if (draftDoc != 'lastDoc' && $writer.el.value == origDoc) {
 				H.remove(draftDoc);
+				H.remove(draftDoc+'-published');
 			} else if (!justPublished) {
 				doneTyping();
 			}