From a51382c52578cf9cb0fd2febc6f83b778efdd9e8 Mon Sep 17 00:00:00 2001
From: Jamie Wong <jamie.lf.wong@gmail.com>
Date: Sat, 23 Dec 2017 13:37:56 -0500
Subject: [PATCH] Hot reloading WIP

---
 application.tsx | 101 ++++++++++++++++++++++++++++++++++++++++++++++
 flamechart.tsx  |   3 +-
 package.json    |   2 +-
 reloadable.tsx  |  51 +++++++++++++++++++++++
 speedscope.tsx  | 105 +++++++++---------------------------------------
 5 files changed, 173 insertions(+), 89 deletions(-)
 create mode 100644 application.tsx
 create mode 100644 reloadable.tsx

diff --git a/application.tsx b/application.tsx
new file mode 100644
index 0000000..d4e9db0
--- /dev/null
+++ b/application.tsx
@@ -0,0 +1,101 @@
+import {h, Component} from 'preact'
+import {StyleSheet, css} from 'aphrodite'
+import {ReloadableComponent} from './reloadable'
+
+import {importFromBGFlameGraph} from './import/bg-flamegraph'
+import {importFromStackprof} from './import/stackprof'
+
+import {Profile} from './profile'
+import {Flamechart, FlamechartView} from './flamechart'
+
+const enum SortOrder {
+  CHRONO,
+  ALPHA
+}
+
+interface ApplicationState {
+  profile: Profile | null
+  flamechart: Flamechart | null
+  sortedFlamechart: Flamechart | null
+  sortOrder: SortOrder
+}
+
+export class Application extends ReloadableComponent<{}, ApplicationState, {}> {
+  constructor() {
+    super()
+    this.state = {
+      profile: null,
+      flamechart: null,
+      sortedFlamechart: null,
+      sortOrder: SortOrder.CHRONO
+    }
+  }
+
+  onDrop = (ev: DragEvent) => {
+    const file = ev.dataTransfer.files.item(0)
+    const reader = new FileReader
+    reader.addEventListener('loadend', () => {
+      const profile = file.name.endsWith('json') ? importFromStackprof(reader.result) : importFromBGFlameGraph(reader.result)
+      const flamechart = new Flamechart(profile)
+      const sortedFlamechart = new Flamechart(profile.sortedAlphabetically())
+      this.setState({profile, flamechart, sortedFlamechart})
+    })
+    reader.readAsText(file)
+    ev.preventDefault()
+  }
+
+  onDragOver = (ev: DragEvent) => {
+    ev.preventDefault()
+  }
+
+  onWindowKeyPress = (ev: KeyboardEvent) => {
+    if (ev.key == 'a') {
+      this.setState({
+        sortOrder: this.state.sortOrder === SortOrder.CHRONO ? SortOrder.ALPHA : SortOrder.CHRONO
+      })
+    }
+  }
+
+  onWindowResize = () => {
+    this.forceUpdate()
+  }
+
+  componentDidMount() {
+    window.addEventListener('resize', this.onWindowResize)
+    // TODO(jlfwong): for this to be safely embeddable, there'll need to be some
+    // way of specify event focus.
+    window.addEventListener('keypress', this.onWindowKeyPress)
+  }
+
+  componentWillUnmount() {
+    window.removeEventListener('resize', this.onWindowResize)
+    window.removeEventListener('keypress', this.onWindowKeyPress)
+  }
+
+  flamechartView: FlamechartView | null
+  flamechartRef = (view: FlamechartView | null) => this.flamechartView = view
+  subcomponents() {
+    return {
+      flamechart: this.flamechartView
+    }
+  }
+
+  render() {
+    const {flamechart, sortedFlamechart, sortOrder} = this.state
+    const flamechartToView = sortOrder == SortOrder.CHRONO ? flamechart : sortedFlamechart
+
+    return <div onDrop={this.onDrop} onDragOver={this.onDragOver} className={css(style.root)}>
+      {flamechartToView &&
+        <FlamechartView ref={this.flamechartRef} flamechart={flamechartToView} />}
+    </div>
+  }
+}
+
+const style = StyleSheet.create({
+  root: {
+    width: '100vw',
+    height: '100vh',
+    overflow: 'hidden'
+  }
+})
+
diff --git a/flamechart.tsx b/flamechart.tsx
index f51c8d6..a28ab15 100644
--- a/flamechart.tsx
+++ b/flamechart.tsx
@@ -1,5 +1,6 @@
 import {h, Component} from 'preact'
 import {StyleSheet, css} from 'aphrodite'
+import {ReloadableComponent} from './reloadable'
 
 import {Profile, Frame, CallTreeNode} from './profile'
 import * as regl from 'regl'
@@ -647,7 +648,7 @@ interface FlamechartViewState {
   logicalSpaceMouse: Vec2
 }
 
-export class FlamechartView extends Component<FlamechartViewProps, FlamechartViewState> {
+export class FlamechartView extends ReloadableComponent<FlamechartViewProps, FlamechartViewState> {
   container: HTMLDivElement | null = null
 
   constructor() {
diff --git a/package.json b/package.json
index b21ae54..efa2092 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,7 @@
   "main": "index.js",
   "scripts": {
     "serve": "parcel -o dev.html -d dist/dev",
-    "release": "parcel build speedscope.tsx"
+    "release": "tsc --noEmit && parcel build speedscope.tsx"
   },
   "author": "",
   "license": "MIT",
diff --git a/reloadable.tsx b/reloadable.tsx
new file mode 100644
index 0000000..aea9e7f
--- /dev/null
+++ b/reloadable.tsx
@@ -0,0 +1,51 @@
+import {Component} from 'preact'
+
+interface SerializedComponent<S, I> {
+  state: S
+  internal: I | null
+  serializedSubcomponents: {[key: string]: any}
+}
+
+export abstract class ReloadableComponent<P, S, I> extends Component<P, S> {
+  serialize(): SerializedComponent<S, I> {
+    const serializedSubcomponents: {[key: string]: any} = Object.create(null)
+
+    const subcomponents = this.subcomponents()
+    for (const key in subcomponents) {
+      const val = subcomponents[key]
+      if (val && val instanceof ReloadableComponent) {
+        serializedSubcomponents[key] = val.serialize()
+      }
+    }
+
+    return {
+      state: this.state,
+      internal: this.serializeInternal(),
+      serializedSubcomponents,
+    }
+  }
+  rehydrate(serialized: SerializedComponent<S, I>) {
+    this.setState(serialized.state)
+    if (serialized.internal) {
+      this.rehydrateInternal(serialized.internal)
+    }
+
+    const subcomponents = this.subcomponents()
+    for (const key in subcomponents) {
+      const val = subcomponents[key]
+      const data = serialized.serializedSubcomponents[key]
+      if (data && val && val instanceof ReloadableComponent) {
+        subcomponents.serialize(data)
+      }
+    }
+  }
+  serializeInternal(): I | null {
+    return null
+  }
+  rehydrateInternal(internal: I) {}
+  subcomponents(): {[key: string]: any} {
+    return Object.create(null)
+  }
+}
+
+
diff --git a/speedscope.tsx b/speedscope.tsx
index ccb4f28..986375b 100644
--- a/speedscope.tsx
+++ b/speedscope.tsx
@@ -1,93 +1,24 @@
-import {h, render, Component} from 'preact'
-import {StyleSheet, css} from 'aphrodite'
+import {h, render} from 'preact'
+import {Application} from'./application'
 
-import {importFromBGFlameGraph} from './import/bg-flamegraph'
-import {importFromStackprof} from './import/stackprof'
-
-import {Profile} from './profile'
-import {Flamechart, FlamechartView} from './flamechart'
-
-const enum SortOrder {
-  CHRONO,
-  ALPHA
-}
-
-interface ApplicationState {
-  profile: Profile | null
-  flamechart: Flamechart | null
-  sortedFlamechart: Flamechart | null
-  sortOrder: SortOrder
-}
-
-class Application extends Component<{}, ApplicationState> {
-  constructor() {
-    super()
-    this.state = {
-      profile: null,
-      flamechart: null,
-      sortedFlamechart: null,
-      sortOrder: SortOrder.CHRONO
+let app: Application | null = null
+const retained = (window as any)['__retained__'] as any
+declare const module: any
+if (module.hot) {
+  module.hot.dispose(() => {
+    if (app) {
+      (window as any)['__retained__'] = app.serialize()
     }
-  }
+  })
+  module.hot.accept()
+}
 
-  onDrop = (ev: DragEvent) => {
-    const file = ev.dataTransfer.files.item(0)
-    const reader = new FileReader
-    reader.addEventListener('loadend', () => {
-      const profile = file.name.endsWith('json') ? importFromStackprof(reader.result) : importFromBGFlameGraph(reader.result)
-      const flamechart = new Flamechart(profile)
-      const sortedFlamechart = new Flamechart(profile.sortedAlphabetically())
-      this.setState({profile, flamechart, sortedFlamechart})
-    })
-    reader.readAsText(file)
-    ev.preventDefault()
-  }
-
-  onDragOver = (ev: DragEvent) => {
-    ev.preventDefault()
-  }
-
-  onWindowKeyPress = (ev: KeyboardEvent) => {
-    if (ev.key == 'a') {
-      this.setState({
-        sortOrder: this.state.sortOrder === SortOrder.CHRONO ? SortOrder.ALPHA : SortOrder.CHRONO
-      })
-    }
-  }
-
-  onWindowResize = () => {
-    this.forceUpdate()
-  }
-
-  componentDidMount() {
-    window.addEventListener('resize', this.onWindowResize)
-    // TODO(jlfwong): for this to be safely embeddable, there'll need to be some
-    // way of specify event focus.
-    window.addEventListener('keypress', this.onWindowKeyPress)
-  }
-
-  componentWillUnmount() {
-    window.removeEventListener('resize', this.onWindowResize)
-    window.removeEventListener('keypress', this.onWindowKeyPress)
-  }
-
-  render() {
-    const {flamechart, sortedFlamechart, sortOrder} = this.state
-    const flamechartToView = sortOrder == SortOrder.CHRONO ? flamechart : sortedFlamechart
-
-    return <div onDrop={this.onDrop} onDragOver={this.onDragOver} className={css(style.root)}>
-      {flamechartToView &&
-        <FlamechartView flamechart={flamechartToView} />}
-    </div>
+function ref(instance: Application | null) {
+  app = instance
+  if (instance && retained) {
+    console.log('rehydrating: ', retained)
+    instance.rehydrate(retained)
   }
 }
 
-const style = StyleSheet.create({
-  root: {
-    width: '100vw',
-    height: '100vh',
-    overflow: 'hidden'
-  }
-})
-
-render(<Application />, document.body)
\ No newline at end of file
+render(<Application ref={ref}/>, document.body, document.body.lastElementChild || undefined)
\ No newline at end of file