From 3f9f6c1147fb976621c1a92063bda9646fd7da20 Mon Sep 17 00:00:00 2001
From: Vadim <korobeinikovv@mail.ru>
Date: Fri, 2 Jul 2021 17:20:33 +0300
Subject: [PATCH] #31 : Update progress manager

---
 src/components/Carousel/Carousel.svelte | 49 ++++++++++++-------------
 src/utils/ProgressManager.js            | 31 ++++++++++++----
 2 files changed, 48 insertions(+), 32 deletions(-)

diff --git a/src/components/Carousel/Carousel.svelte b/src/components/Carousel/Carousel.svelte
index aabbe25..5ee99ec 100644
--- a/src/components/Carousel/Carousel.svelte
+++ b/src/components/Carousel/Carousel.svelte
@@ -18,8 +18,16 @@
   const dispatch = createEventDispatcher()
 
   const directionFnDescription = {
-    [NEXT]: showNextPage,
-    [PREV]: showPrevPage
+    [NEXT]: () => {
+      progressManager.start(() => {
+        showNextPage()
+      })
+    },
+    [PREV]: () => {
+      progressManager.start(() => {
+        showPrevPage()
+      })
+    }
   }
 
   /**
@@ -67,7 +75,7 @@
   /**
    * Pause autoplay on focus
    */
-  export let pauseOnFocus = false
+  export let pauseOnFocus = true
 
   /**
    * Current page indicator dots
@@ -117,15 +125,12 @@
     }
   })
 
-  let autoplayInterval = null
   $: {
     if (pauseOnFocus) {
       if (focused) {
         progressManager.pause()
-        clearAutoplay()
       } else {
         progressManager.resume()
-        applyAutoplay()
       }
     }
   }
@@ -146,19 +151,6 @@
 
     offsetPage(false)
   }
-
-  function applyAutoplay() {
-    if (autoplay && !autoplayInterval) {
-      autoplayInterval = setInterval(() => {
-        directionFnDescription[autoplayDirection]()
-      }, autoplayDuration)
-    }
-  }
-
-  function clearAutoplay() {
-    clearInterval(autoplayInterval)
-    autoplayInterval = null
-  }
   
   function addClones() {
     const first = pagesElement.children[0]
@@ -167,6 +159,12 @@
     pagesElement.append(first.cloneNode(true))
   }
 
+  function applyAutoplay() {
+    if (autoplay) {
+      directionFnDescription[autoplayDirection]()
+    }
+  }
+
   let cleanupFns = []
 
   onMount(() => {
@@ -174,11 +172,7 @@
       await tick()
       cleanupFns.push(store.subscribe(value => {
         currentPageIndex = value.currentPageIndex
-        
-        progressManager.reset() // clear interval out of condition in case autoplay was changed reactively
-        if (autoplay) {
-          progressManager.start()
-        }
+        console.log('currentPageIndex', currentPageIndex)
       }))
       if (pagesElement && pageWindowElement) {
         // load first and last child to clone them 
@@ -189,13 +183,14 @@
         store.init(initialPageIndex + Number(infinite))
         applyPageSizes()
       }
+
       applyAutoplay()
+
       addResizeEventListener(applyPageSizes)
     })()
   })
 
   onDestroy(() => {
-    clearAutoplay()
     removeResizeEventListener(applyPageSizes)
     cleanupFns.filter(fn => fn && typeof fn === 'function').forEach(fn => fn())
   })
@@ -219,12 +214,14 @@
   // Disable page change while animation is in progress
   let disabled = false
   function safeChangePage(cb, options) {
+    applyAutoplay()
     const animated = get(options, 'animated', true)
     if (disabled) return
     cb()
     disabled = true
     setTimeout(() => {
       disabled = false
+      
     }, animated ? duration : 0)
   }
 
@@ -258,6 +255,7 @@
     _duration = 0
   }
   function handleThreshold(event) {
+    // TODO: is it correct?
     directionFnDescription[event.detail.direction]()
   }
   function handleSwipeMove(event) {
@@ -333,6 +331,7 @@
       ></Dots>
     </slot>
   {/if}
+  {progressValue}
   <Progress value={progressValue} />
 </div>
 
diff --git a/src/utils/ProgressManager.js b/src/utils/ProgressManager.js
index 260252d..6c1f0e5 100644
--- a/src/utils/ProgressManager.js
+++ b/src/utils/ProgressManager.js
@@ -1,9 +1,15 @@
-const PROGRESS_STEPS_COUNT = 100
+const PROGRESS_STEPS_COUNT = 10
+
+const setIntervalImmediately = (fn, ms) => {
+  fn();
+  return setInterval(fn, ms);
+}
 
 export class ProgressManager {
   #autoplayDuration
   #onValueChange
 
+
   #interval
   #paused = false
 
@@ -15,18 +21,26 @@ export class ProgressManager {
     this.#onValueChange = onValueChange
   }
 
-  start() {
-    let value = 0
-    let progress = 0
-    const stepMs = this.#autoplayDuration / PROGRESS_STEPS_COUNT
+  start(onFinish) {
+    this.reset()
 
-    this.#interval = setInterval(() => {
+    const stepMs = this.#autoplayDuration / PROGRESS_STEPS_COUNT
+    let progress = -stepMs
+
+    this.#interval = setIntervalImmediately(() => {
       if (this.#paused) {
         return 
       }
       progress += stepMs
-      value = progress / this.#autoplayDuration
+
+      const value = progress / this.#autoplayDuration
       this.#onValueChange(value)
+
+      if (value > 1) {
+        this.reset()
+        onFinish()
+        this.start(onFinish)
+      }
     }, stepMs)
   }
 
@@ -40,5 +54,8 @@ export class ProgressManager {
 
   reset() {
     clearInterval(this.#interval)
+    // this.#onValueChange(0)
   }
+
+  // TODO: add on destroy
 }