Use a monotonic clock

[vopamoi] / vopamoi.ts

diff --git a/vopamoi.ts b/vopamoi.ts
index fe3d491630f9e5781bdc7ba62f2f6ee0ad731b7e..271354fc7aa3a52192f092a88a9df8de2f1fb341 100644 (file)
--- a/vopamoi.ts
+++ b/vopamoi.ts
@@ -13,22 +13,57 @@ function splitN(str: string, delimiter: string, limit: number = MAX_SAFE_INTEGER
   return at === -1 ? [str] : [str.substring(0, at)].concat(splitN(str.substring(at + delimiter.length), delimiter, limit - 1));
 }
 
   return at === -1 ? [str] : [str.substring(0, at)].concat(splitN(str.substring(at + delimiter.length), delimiter, limit - 1));
 }
 

+// A clock that never goes backwards; monotonic.
+function Clock() {
+  var previousNow = Date.now();
+  return {
+    now: function (): number {
+      const now = Date.now();
+      if (now > previousNow) {
+        previousNow = now;
+        return now;
+      }
+      return ++previousNow;
+    },
+  };
+}
+const clock = Clock();
+

 const Model = {
 const Model = {

-  addTask: function (timestamp: string, description: string) {
+  addTask: function (timestamp: string, description: string): Element {

     const task = document.createElement("div");
     task.appendChild(document.createTextNode(description));
     task.setAttribute("class", "task");
     task.setAttribute("tabindex", "0");
     task.setAttribute("data-created", timestamp);
     document.getElementById("tasks")!.appendChild(task);
     const task = document.createElement("div");
     task.appendChild(document.createTextNode(description));
     task.setAttribute("class", "task");
     task.setAttribute("tabindex", "0");
     task.setAttribute("data-created", timestamp);
     document.getElementById("tasks")!.appendChild(task);

-    task.focus();
+    return task;

   },
 
   },
 

-  destroyTask: function (createTimestamp: string) {
-    const task = this.getTask(createTimestamp);
-    if (task) {
-      task.parentElement!.removeChild(task);
+  edit: function (createTimestamp: string, newDescription: string): Element | null {
+    const target = this.getTask(createTimestamp);
+    if (!target) return null;
+    if (target.hasAttribute("data-description")) {
+      // Oh no: An edit has arrived from a replica while a local edit is in progress.
+      const input = target.children[0] as HTMLInputElement;
+      if (
+        input.value === target.getAttribute("data-description") &&
+        input.selectionStart === 0 &&
+        input.selectionEnd === input.value.length
+      ) {
+        // No local changes have actually been made yet.  Change the contents of the edit box!
+        input.value = newDescription;
+        input.select();
+      } else {
+        // No great options.
+        // Prefer not to interrupt the local user's edit.
+        // The remote edit is mostly lost; this mostly becomes last-write-wins.
+        target.setAttribute("data-description", newDescription);
+      }
+    } else {
+      target.textContent = newDescription;

     }
     }

+    return target;

   },
 
   getPriority: function (task: Element): number {
   },
 
   getPriority: function (task: Element): number {


@@ -38,6 +73,10 @@ const Model = {
     return parseFloat(task.getAttribute("data-created")!);
   },
 
     return parseFloat(task.getAttribute("data-created")!);
   },
 

+  getState: function (task: Element): string {
+    return task.getAttribute("data-state") ?? "todo";
+  },
+

   getTask: function (createTimestamp: string) {
     for (const task of document.getElementsByClassName("task")) {
       if (task.getAttribute("data-created") === createTimestamp) {
   getTask: function (createTimestamp: string) {
     for (const task of document.getElementsByClassName("task")) {
       if (task.getAttribute("data-created") === createTimestamp) {


@@ -46,27 +85,26 @@ const Model = {
     }
   },
 
     }
   },
 

-  setPriority: function (createTimestamp: string, priority: number) {
+  setPriority: function (createTimestamp: string, priority: number): Element | null {

     const target = this.getTask(createTimestamp);
     const target = this.getTask(createTimestamp);

-    if (!target) return;
+    if (!target) return null;

     target.setAttribute("data-priority", `${priority}`);
     for (const task of document.getElementsByClassName("task")) {
       if (task !== target && this.getPriority(task) > priority) {
         task.parentElement!.insertBefore(target, task);
     target.setAttribute("data-priority", `${priority}`);
     for (const task of document.getElementsByClassName("task")) {
       if (task !== target && this.getPriority(task) > priority) {
         task.parentElement!.insertBefore(target, task);

-        target instanceof HTMLElement && target.focus();
-        return;
+        return target;

       }
     }
     document.getElementById("tasks")!.appendChild(target);
       }
     }
     document.getElementById("tasks")!.appendChild(target);

-    target instanceof HTMLElement && target.focus();
+    return target;

   },
 
   setState: function (stateTimestamp: string, createTimestamp: string, state: string) {
     const task = this.getTask(createTimestamp);
     if (task) {
   },
 
   setState: function (stateTimestamp: string, createTimestamp: string, state: string) {
     const task = this.getTask(createTimestamp);
     if (task) {

-      task.setAttribute(`data-${state}`, stateTimestamp);
+      task.setAttribute("data-state", state);

       if (task instanceof HTMLElement) {
       if (task instanceof HTMLElement) {

-        task.style.display = "none"; // Until view filtering
+        task.style.display = state == "todo" ? "block" : "none"; // Until view filtering

       }
     }
   },
       }
     }
   },


@@ -78,18 +116,19 @@ function Log(prefix: string = "vp-") {
     apply: function (entry: string) {
       const [timestamp, command, data] = splitN(entry, " ", 2);
       if (command == "Create") {
     apply: function (entry: string) {
       const [timestamp, command, data] = splitN(entry, " ", 2);
       if (command == "Create") {

-        Model.addTask(timestamp, data);
+        return Model.addTask(timestamp, data);

       }
       }

-      if (command == "Destroy") {
-        Model.destroyTask(data.split(" ", 1)[0]);
+      if (command == "Edit") {
+        const [createTimestamp, description] = splitN(data, " ", 1);
+        return Model.edit(createTimestamp, description);

       }
       if (command == "State") {
         const [createTimestamp, state] = splitN(data, " ", 1);
       }
       if (command == "State") {
         const [createTimestamp, state] = splitN(data, " ", 1);

-        Model.setState(timestamp, createTimestamp, state);
+        return Model.setState(timestamp, createTimestamp, state);

       }
       if (command == "Priority") {
         const [createTimestamp, newPriority] = splitN(data, " ", 1);
       }
       if (command == "Priority") {
         const [createTimestamp, newPriority] = splitN(data, " ", 1);

-        Model.setPriority(createTimestamp, parseFloat(newPriority));
+        return Model.setPriority(createTimestamp, parseFloat(newPriority));

       }
     },
 
       }
     },
 


@@ -99,7 +138,7 @@ function Log(prefix: string = "vp-") {
 
     recordAndApply: function (entry: string) {
       this.record(entry);
 
     recordAndApply: function (entry: string) {
       this.record(entry);

-      this.apply(entry);
+      return this.apply(entry);

     },
 
     replay: function () {
     },
 
     replay: function () {


@@ -116,37 +155,86 @@ function Log(prefix: string = "vp-") {
 }
 const log = Log();
 
 }
 const log = Log();
 

+const undoLog: string[] = [];
+

 const UI = {
 const UI = {

-  addTask: function (description: string) {
-    log.recordAndApply(`${Date.now()} Create ${description}`);
+  addTask: function (description: string): Element {
+    const now = clock.now();
+    undoLog.push(`State ${now} deleted`);
+    return <Element>log.recordAndApply(`${now} Create ${description}`);
+  },
+  edit: function (createTimestamp: string, newDescription: string, oldDescription: string) {
+    undoLog.push(`Edit ${createTimestamp} ${oldDescription}`);
+    return log.recordAndApply(`${clock.now()} Edit ${createTimestamp} ${newDescription}`);

   },
   },

-  destroyTask: function (createTimestamp: string) {
-    log.recordAndApply(`${Date.now()} Destroy ${createTimestamp} ${Model.getTask(createTimestamp)?.textContent}`);
+  setPriority: function (createTimestamp: string, newPriority: number, oldPriority: number) {
+    undoLog.push(`Priority ${createTimestamp} ${oldPriority}`);
+    return log.recordAndApply(`${clock.now()} Priority ${createTimestamp} ${newPriority}`);

   },
   },

-  setPriority: function (createTimestamp: string, priority: number) {
-    log.recordAndApply(`${Date.now()} Priority ${createTimestamp} ${priority}`);
+  setState: function (createTimestamp: string, newState: string, oldState: string) {
+    undoLog.push(`State ${createTimestamp} ${oldState}`);
+    return log.recordAndApply(`${clock.now()} State ${createTimestamp} ${newState}`);

   },
   },

-  setState: function (createTimestamp: string, state: string) {
-    log.recordAndApply(`${Date.now()} State ${createTimestamp} ${state}`);
+  undo: function () {
+    if (undoLog.length > 0) {
+      return log.recordAndApply(`${clock.now()} ${undoLog.pop()}`);
+    }

   },
 };
 
 const BrowserUI = {
   },
 };
 
 const BrowserUI = {

-  addTask: function () {
+  addTask: function (event: KeyboardEvent) {

     const input = <HTMLInputElement>document.getElementById("taskName");
     if (input.value) {
     const input = <HTMLInputElement>document.getElementById("taskName");
     if (input.value) {

-      UI.addTask(input.value);
+      const task = UI.addTask(input.value);
+      if (task && task instanceof HTMLElement) task.focus();

       input.value = "";
       input.value = "";

+      if (event.getModifierState("Control")) {
+        this.setPriority(task, null, document.getElementsByClassName("task")[0]);
+      }

     }
   },
 
     }
   },
 

-  destroyTask: function () {
-    const createTimestamp = document.activeElement?.getAttribute("data-created");
-    this.moveCursor(1) || this.moveCursor(-1);
-    return UI.destroyTask(createTimestamp!);
+  beginEdit: function (event: Event) {
+    const task = document.activeElement;
+    if (!task) return;
+    const input = document.createElement("input");
+    const oldDescription = task.textContent!;
+    task.setAttribute("data-description", oldDescription);
+    input.value = oldDescription;
+    input.addEventListener("blur", BrowserUI.completeEdit, { once: true });
+    task.textContent = "";
+    task.appendChild(input);
+    input.focus();
+    input.select();
+    event.preventDefault();

   },
 
   },
 

-  focusTaskNameInput: function (event: any) {
+  completeEdit: function (event: Event) {
+    const input = event.target as HTMLInputElement;
+    const task = input.parentElement!;
+    const oldDescription = task.getAttribute("data-description")!;
+    const newDescription = input.value;
+    input.removeEventListener("blur", BrowserUI.completeEdit);
+    task.removeChild(task.children[0]);
+    task.removeAttribute("data-description");
+    task.focus();
+    if (newDescription === oldDescription) {
+      task.textContent = oldDescription;
+    } else {
+      UI.edit(task.getAttribute("data-created")!, newDescription, oldDescription);
+    }
+  },
+
+  firstVisibleTask: function () {
+    for (const task of document.getElementsByClassName("task")) {
+      if (task instanceof HTMLElement && task.style.display !== "none") {
+        return task;
+      }
+    }
+  },
+
+  focusTaskNameInput: function (event: Event) {

     document.getElementById("taskName")!.focus();
     event.preventDefault();
   },
     document.getElementById("taskName")!.focus();
     event.preventDefault();
   },


@@ -195,26 +283,40 @@ const BrowserUI = {
   // Change task's priority to be between other tasks a and b.
   setPriority: function (task: Element, a: Element | null, b: Element | null) {
     const aPriority = a === null ? 0 : Model.getPriority(a);
   // Change task's priority to be between other tasks a and b.
   setPriority: function (task: Element, a: Element | null, b: Element | null) {
     const aPriority = a === null ? 0 : Model.getPriority(a);

-    const bPriority = b === null ? Date.now() : Model.getPriority(b);
+    const bPriority = b === null ? clock.now() : Model.getPriority(b);

     console.assert(aPriority < bPriority, aPriority, "<", bPriority);
     const span = bPriority - aPriority;
     const newPriority = aPriority + 0.1 * span + 0.8 * span * Math.random();
     console.assert(aPriority < newPriority && newPriority < bPriority, aPriority, "<", newPriority, "<", bPriority);
     const newPriorityRounded = Math.round(newPriority);
     const okToRound = aPriority < newPriorityRounded && newPriorityRounded < bPriority;
     console.assert(aPriority < bPriority, aPriority, "<", bPriority);
     const span = bPriority - aPriority;
     const newPriority = aPriority + 0.1 * span + 0.8 * span * Math.random();
     console.assert(aPriority < newPriority && newPriority < bPriority, aPriority, "<", newPriority, "<", bPriority);
     const newPriorityRounded = Math.round(newPriority);
     const okToRound = aPriority < newPriorityRounded && newPriorityRounded < bPriority;

-    UI.setPriority(task.getAttribute("data-created")!, okToRound ? newPriorityRounded : newPriority);
+    UI.setPriority(task.getAttribute("data-created")!, okToRound ? newPriorityRounded : newPriority, Model.getPriority(task));
+    task instanceof HTMLElement && task.focus();

   },
 
   },
 

-  setState: function (state: string) {
-    const createTimestamp = document.activeElement?.getAttribute("data-created");
+  setState: function (newState: string) {
+    const task = document.activeElement;
+    if (!task) return;
+    const oldState = Model.getState(task);
+    if (newState === oldState) return;
+    const createTimestamp = task.getAttribute("data-created")!;

     this.moveCursor(1) || this.moveCursor(-1);
     this.moveCursor(1) || this.moveCursor(-1);

-    return UI.setState(createTimestamp!, state);
+    return UI.setState(createTimestamp, newState, oldState);
+  },
+
+  undo: function () {
+    const ret = UI.undo();
+    if (ret && ret instanceof HTMLElement) ret.focus();

   },
 };
 
 function handleKey(event: any) {
   if (event.target.tagName === "INPUT") {
   },
 };
 
 function handleKey(event: any) {
   if (event.target.tagName === "INPUT") {

-    if (event.key == "Enter") return BrowserUI.addTask();
+    if (event.target.id === "taskName") {
+      if (event.key == "Enter") return BrowserUI.addTask(event);
+    } else {
+      if (event.key == "Enter") return BrowserUI.completeEdit(event);
+    }

   } else {
     if (event.key == "j") return BrowserUI.moveCursor(1);
     if (event.key == "k") return BrowserUI.moveCursor(-1);
   } else {
     if (event.key == "j") return BrowserUI.moveCursor(1);
     if (event.key == "k") return BrowserUI.moveCursor(-1);


@@ -225,11 +327,15 @@ function handleKey(event: any) {
     if (event.key == "w") return BrowserUI.setState("waiting");
     if (event.key == "d") return BrowserUI.setState("done");
     if (event.key == "c") return BrowserUI.setState("cancelled");
     if (event.key == "w") return BrowserUI.setState("waiting");
     if (event.key == "d") return BrowserUI.setState("done");
     if (event.key == "c") return BrowserUI.setState("cancelled");

-    if (event.key == "X") return BrowserUI.destroyTask();
+    if (event.key == "t") return BrowserUI.setState("todo");
+    if (event.key == "X") return BrowserUI.setState("deleted");
+    if (event.key == "u") return BrowserUI.undo();
+    if (event.key == "e") return BrowserUI.beginEdit(event);

   }
 }
 
 function browserInit() {
   document.body.addEventListener("keydown", handleKey, { capture: false });
   log.replay();
   }
 }
 
 function browserInit() {
   document.body.addEventListener("keydown", handleKey, { capture: false });
   log.replay();

+  BrowserUI.firstVisibleTask()?.focus();

 }
 }