1 files changed, 127 insertions, 0 deletions
diff --git a/src/content/presenters/Hint.ts b/src/content/presenters/Hint.ts
new file mode 100644
index 0000000..60c0f4c
--- /dev/null
+++ b/src/content/presenters/Hint.ts
@@ -0,0 +1,127 @@
+import * as doms from '../../shared/utils/dom';
+
+interface Point {
+  x: number;
+  y: number;
+}
+
+const hintPosition = (element: Element): Point => {
+  let { left, top, right, bottom } = doms.viewportRect(element);
+
+  if (element.tagName !== 'AREA') {
+    return { x: left, y: top };
+  }
+
+  return {
+    x: (left + right) / 2,
+    y: (top + bottom) / 2,
+  };
+};
+
+export default abstract class Hint {
+  private hint: HTMLElement;
+
+  private tag: string;
+
+  constructor(target: HTMLElement, tag: string) {
+    this.tag = tag;
+
+    let doc = target.ownerDocument;
+    if (doc === null) {
+      throw new TypeError('ownerDocument is null');
+    }
+
+    let { x, y } = hintPosition(target);
+    let { scrollX, scrollY } = window;
+
+    let hint = doc.createElement('span');
+    hint.className = 'vimvixen-hint';
+    hint.textContent = tag;
+    hint.style.left = x + scrollX + 'px';
+    hint.style.top = y + scrollY + 'px';
+
+    doc.body.append(hint);
+
+    this.hint = hint;
+    this.show();
+  }
+
+  show(): void {
+    this.hint.style.display = 'inline';
+  }
+
+  hide(): void {
+    this.hint.style.display = 'none';
+  }
+
+  remove(): void {
+    this.hint.remove();
+  }
+
+  getTag(): string {
+    return this.tag;
+  }
+}
+
+export class LinkHint extends Hint {
+  private target: HTMLAnchorElement | HTMLAreaElement;
+
+  constructor(target: HTMLAnchorElement | HTMLAreaElement, tag: string) {
+    super(target, tag);
+
+    this.target = target;
+  }
+
+  getLink(): string {
+    return this.target.href;
+  }
+
+  getLinkTarget(): string | null {
+    return this.target.getAttribute('target');
+  }
+
+  click(): void {
+    this.target.click();
+  }
+}
+
+export class InputHint extends Hint {
+  private target: HTMLElement;
+
+  constructor(target: HTMLElement, tag: string) {
+    super(target, tag);
+
+    this.target = target;
+  }
+
+  activate(): void {
+    let target = this.target;
+    switch (target.tagName.toLowerCase()) {
+    case 'input':
+      switch ((target as HTMLInputElement).type) {
+      case 'file':
+      case 'checkbox':
+      case 'radio':
+      case 'submit':
+      case 'reset':
+      case 'button':
+      case 'image':
+      case 'color':
+        return target.click();
+      default:
+        return target.focus();
+      }
+    case 'textarea':
+      return target.focus();
+    case 'button':
+    case 'summary':
+      return target.click();
+    default:
+      if (doms.isContentEditable(target)) {
+        return target.focus();
+      } else if (target.hasAttribute('tabindex')) {
+        return target.click();
+      }
+    }
+  }
+}