widgets: Add todo widget.

static/js/todo_widget.js

@@ -0,0 +1,192 @@
+var todo_widget = (function () {
+
+var exports = {};
+
+exports.task_data_holder = function (is_my_task_list) {
+    var self = {};
+
+    var all_tasks = [];
+    var pending_tasks = [];
+    var completed_tasks = [];
+    var my_idx = 0;
+
+    self.get_widget_data = function () {
+
+        var widget_data = {
+            pending_tasks: pending_tasks,
+            completed_tasks: completed_tasks,
+        };
+
+        return widget_data;
+    };
+
+    self.check_task = {
+        task_exists: function (task) {
+            var task_exists = _.any(all_tasks, function (item) {
+                return item.task === task;
+            });
+            return task_exists;
+        },
+    };
+
+    self.handle = {
+        new_task: {
+            outbound: function (task) {
+                var event = {
+                    type: 'new_task',
+                    key: my_idx,
+                    task: task,
+                    completed: false,
+                };
+                my_idx += 1;
+
+                if (is_my_task_list && !self.check_task.task_exists(task)) {
+                    return event;
+                }
+                return;
+            },
+
+            inbound: function (sender_id, data) {
+                var idx = data.key;
+                var task = data.task;
+                var completed = data.completed;
+
+                var task_data = {
+                    task: task,
+                    user_id: sender_id,
+                    key: idx,
+                    completed: completed,
+                };
+
+                if (!self.check_task.task_exists(task)) {
+                    pending_tasks.push(task_data);
+                    all_tasks.push(task_data);
+
+                    if (my_idx <= idx) {
+                        my_idx = idx + 1;
+                    }
+                }
+            },
+        },
+
+        strike: {
+            outbound: function (key) {
+                var event = {
+                    type: 'strike',
+                    key: key,
+                };
+
+                if (is_my_task_list) {
+                    return event;
+                }
+                return;
+            },
+
+            inbound: function (sender_id, data) {
+                var key = data.key;
+                var task = all_tasks[key];
+                var index;
+
+                if (task === undefined) {
+                    blueslip.error('unknown key for tasks: ' + key);
+                    return;
+                }
+
+                all_tasks[key].completed = !all_tasks[key].completed;
+
+                // toggle
+                if (task.completed) {
+                    index = pending_tasks.indexOf(task);
+                    pending_tasks.splice(index, 1);
+                    completed_tasks.unshift(task);
+                } else {
+                    index = completed_tasks.indexOf(task);
+                    completed_tasks.splice(index, 1);
+                    pending_tasks.push(task);
+                }
+            },
+        },
+    };
+
+    self.handle_event = function (sender_id, data) {
+        var type = data.type;
+        if (self.handle[type]) {
+            self.handle[type].inbound(sender_id, data);
+        }
+    };
+
+    return self;
+};
+
+exports.activate = function (opts) {
+    var elem = opts.elem;
+    var callback = opts.callback;
+
+    var is_my_task_list = people.is_my_user_id(opts.message.sender_id);
+    var task_data = exports.task_data_holder(is_my_task_list);
+
+    function render() {
+        var html = templates.render('todo-widget');
+        elem.html(html);
+
+        elem.find("button.add-task").on('click', function (e) {
+            e.stopPropagation();
+            elem.find(".widget-error").text('');
+            var task = elem.find("input.add-task").val().trim();
+
+            if (task === '') {
+                return;
+            }
+
+            elem.find(".add-task").val('').focus();
+
+            var task_exists = task_data.check_task.task_exists(task);
+            if (task_exists) {
+                elem.find(".widget-error").text(i18n.t('Task already exists'));
+                return;
+            }
+
+            var data = task_data.handle.new_task.outbound(task);
+            callback(data);
+        });
+    }
+
+    function render_results() {
+        var widget_data = task_data.get_widget_data();
+        var html = templates.render('todo-widget-tasks', widget_data);
+        elem.find('ul.todo-widget').html(html);
+        elem.find(".widget-error").text('');
+
+        if (!is_my_task_list) {
+            elem.find(".add-task-bar").hide();
+            elem.find("button.task").attr('disabled', true);
+        }
+
+        elem.find("button.task").on('click', function (e) {
+            e.stopPropagation();
+            var key = $(e.target).attr('data-key');
+
+            var data = task_data.handle.strike.outbound(key);
+            callback(data);
+        });
+    }
+
+    elem.handle_events = function (events) {
+        _.each(events, function (event) {
+            task_data.handle_event(event.sender_id, event.data);
+        });
+        render_results();
+    };
+
+    render();
+    render_results();
+};
+
+return exports;
+
+}());
+if (typeof module !== 'undefined') {
+    module.exports = todo_widget;
+}
+
+window.todo_widget = todo_widget;