Discover frames on search by count of connections

When a tab switches pages quickly, a disconnect event on top frame is
sometime delivered after second connect event. In addition,
`tabs.onUpdated()` event is independent on port connection event.

Now the background script finds alive frames by only port connection.

3 files changed, 21 insertions, 35 deletions

diff --git a/src/background/Application.ts b/src/background/Application.ts
index c7bcc42..b439d19 100644
--- a/src/background/Application.ts
+++ b/src/background/Application.ts
@@ -31,7 +31,6 @@ export default class Application {
 
     browser.tabs.onUpdated.addListener((tabId: number, info) => {
       if (info.status == "loading") {
-        this.frameRepository.clearFrameIds(tabId);
         this.findRepository.deleteLocalState(tabId);
       }
     });
diff --git a/src/background/repositories/ReadyFrameRepository.ts b/src/background/repositories/ReadyFrameRepository.ts
index aa5d986..c993858 100644
--- a/src/background/repositories/ReadyFrameRepository.ts
+++ b/src/background/repositories/ReadyFrameRepository.ts
@@ -2,11 +2,9 @@ import MemoryStorage from "../infrastructures/MemoryStorage";
 
 const REPOSITORY_KEY = "readyFrameRepository";
 
-type State = { [tabId: number]: number[] };
+type State = { [tabId: number]: { [frameId: number]: number } };
 
 export default interface ReadyFrameRepository {
-  clearFrameIds(tabId: number): Promise<void>;
-
   addFrameId(tabId: number, frameId: number): Promise<void>;
 
   removeFrameId(tabId: number, frameId: number): Promise<void>;
@@ -21,22 +19,14 @@ export class ReadyFrameRepositoryImpl implements ReadyFrameRepository {
     this.cache = new MemoryStorage();
   }
 
-  clearFrameIds(tabId: number): Promise<void> {
-    let state: State | undefined = this.cache.get(REPOSITORY_KEY);
-    if (typeof state === "undefined") {
-      state = {};
-    }
-    delete state[tabId];
-    this.cache.set(REPOSITORY_KEY, state);
-    return Promise.resolve();
-  }
-
   addFrameId(tabId: number, frameId: number): Promise<void> {
     let state: State | undefined = this.cache.get(REPOSITORY_KEY);
     if (typeof state === "undefined") {
       state = {};
     }
-    state[tabId] = (state[tabId] || []).concat(frameId).sort();
+    const tab = state[tabId] || {};
+    tab[frameId] = (tab[frameId] || 0) + 1;
+    state[tabId] = tab;
     this.cache.set(REPOSITORY_KEY, state);
     return Promise.resolve();
   }
@@ -50,7 +40,15 @@ export class ReadyFrameRepositoryImpl implements ReadyFrameRepository {
     if (typeof ids === "undefined") {
       return Promise.resolve();
     }
-    state[tabId] = ids.filter((id) => id != frameId);
+    const tab = state[tabId] || {};
+    tab[frameId] = (tab[frameId] || 0) - 1;
+    if (tab[frameId] == 0) {
+      delete tab[frameId];
+    }
+    if (Object.keys(tab).length === 0) {
+      delete state[tabId];
+    }
+
     this.cache.set(REPOSITORY_KEY, state);
     return Promise.resolve();
   }
@@ -60,6 +58,13 @@ export class ReadyFrameRepositoryImpl implements ReadyFrameRepository {
     if (typeof state === "undefined") {
       return Promise.resolve(undefined);
     }
-    return Promise.resolve(state[tabId]);
+    const tab = state[tabId];
+    if (typeof tab === "undefined") {
+      return Promise.resolve(undefined);
+    }
+    const frameIds = Object.keys(tab)
+      .map((v) => Number(v))
+      .sort();
+    return Promise.resolve(frameIds);
   }
 }
diff --git a/src/background/usecases/ReadyFrameUseCase.ts b/src/background/usecases/ReadyFrameUseCase.ts
deleted file mode 100644
index 81bee0c..0000000
--- a/src/background/usecases/ReadyFrameUseCase.ts
+++ /dev/null
@@ -1,18 +0,0 @@
-import { inject, injectable } from "tsyringe";
-import ReadyFrameRepository from "../repositories/ReadyFrameRepository";
-
-@injectable()
-export default class ReadyFrameUseCase {
-  constructor(
-    @inject("ReadyFrameRepository")
-    private readonly frameRepository: ReadyFrameRepository
-  ) {}
-
-  async addReadyFrame(tabId: number, frameId: number): Promise<void> {
-    return this.frameRepository.addFrameId(tabId, frameId);
-  }
-
-  async clearReadyFrame(tabId: number): Promise<void> {
-    return this.frameRepository.clearFrameIds(tabId);
-  }
-}