From 4da9742f7f72b7b8ea82dc74787eb382ce0f81c3 Mon Sep 17 00:00:00 2001
From: "ext.jeremy.guillot@maxicoffee.domains" <j.guillot_ext@maxicoffee.com>
Date: Sun, 15 Mar 2026 18:44:51 +0100
Subject: [PATCH] perf(reader): virtual rendering avec IntersectionObserver en
 mode scroll
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Remplace le rendu de tous les composants ReaderPage par un système de
virtual rendering : seules les pages dans la zone ±1000px du viewport
sont montées, les autres sont remplacées par un placeholder dimensionné.

- InfiniteReader : ajout visibilityObserver + mountedPageIndices (Set
  réactif), helper getPlaceholderHeight(), suppression de 5 console.log
- ReaderPage : prop windowWidth injectable depuis le parent, listener
  resize conditionnel, suppression de 3 console.log de debug
---
 .../components/InfiniteReader.vue             | 91 +++++++++++++------
 .../presentation/components/ReaderPage.vue    | 38 ++++----
 2 files changed, 84 insertions(+), 45 deletions(-)

diff --git a/assets/vue/app/domain/reader/presentation/components/InfiniteReader.vue b/assets/vue/app/domain/reader/presentation/components/InfiniteReader.vue
index e6d4f0c..be5636e 100644
--- a/assets/vue/app/domain/reader/presentation/components/InfiniteReader.vue
+++ b/assets/vue/app/domain/reader/presentation/components/InfiniteReader.vue
@@ -1,10 +1,26 @@
 <template>
     <div class="infinite-reader" ref="containerRef">
-        <div v-for="(page, index) in pages" :key="index" class="page-wrapper">
+        <div v-for="(page, index) in pages" :key="index"
+             class="page-wrapper" :data-page-index="index">
+
+            <!-- Pas d'URL : spinner de chargement -->
             <div v-if="!page?.url" class="loading">
                 <div class="animate-spin rounded-full h-12 w-12 border-b-2 border-blue-600"></div>
             </div>
-            <ReaderPage v-else :page-data="page" :page-number="index + 1" :zoom="zoom" :double-page-mode="doublePageMode" loading="lazy" />
+
+            <!-- Hors de la zone de rendu : placeholder dimensionné -->
+            <div v-else-if="!mountedPageIndices.has(index)"
+                 class="page-placeholder"
+                 :style="{ height: getPlaceholderHeight(page) + 'px' }" />
+
+            <!-- Dans la zone : composant complet -->
+            <ReaderPage v-else
+                :page-data="page"
+                :page-number="index + 1"
+                :zoom="zoom"
+                :double-page-mode="doublePageMode"
+                :window-width="windowWidth"
+                loading="lazy" />
         </div>
 
         <!-- Bouton flottant pour revenir en haut -->
@@ -33,7 +49,7 @@
 </template>
 
 <script setup>
-    import { nextTick, onMounted, onUnmounted, ref, watch } from 'vue';
+    import { nextTick, onMounted, onUnmounted, reactive, ref, watch } from 'vue';
 import { useHeaderStore } from '../../../../shared/stores/headerStore';
 import ReaderPage from './ReaderPage.vue';
 
@@ -57,6 +73,8 @@ import ReaderPage from './ReaderPage.vue';
     const headerStore = useHeaderStore();
     const containerRef = ref(null);
     const observer = ref(null);
+    const visibilityObserver = ref(null);
+    const mountedPageIndices = reactive(new Set());
     const windowWidth = ref(window.innerWidth);
 
     // État unique pour tous les boutons flottants avec timer de 3 secondes
@@ -76,24 +94,46 @@ import ReaderPage from './ReaderPage.vue';
         });
     };
 
-    const setupIntersectionObserver = () => {
-        if (observer.value) {
-            observer.value.disconnect();
-        }
+    // Calcul de la hauteur du placeholder — miroir exact du maxWidth de ReaderPage
+    const getPlaceholderHeight = (page) => {
+        const dims = page?.dimensions;
+        if (!dims?.width || !dims?.height) return 800;
+        const displayWidth = windowWidth.value < 1200
+            ? Math.min(dims.width, windowWidth.value * 0.95)
+            : Math.min(dims.width, 1200);
+        return Math.round((dims.height / dims.width) * displayWidth);
+    };
+
+    const setupObservers = () => {
+        observer.value?.disconnect();
+        visibilityObserver.value?.disconnect();
 
         observer.value = new IntersectionObserver(observeIntersection, {
             root: null,
             threshold: 0.5
         });
 
-        nextTick(() => {
-            const pageElements = containerRef.value?.querySelectorAll('.page-wrapper');
-            if (pageElements) {
-                pageElements.forEach((element, index) => {
-                    element.setAttribute('data-page-index', index);
-                    observer.value.observe(element);
+        visibilityObserver.value = new IntersectionObserver(
+            (entries) => {
+                entries.forEach(entry => {
+                    const idx = parseInt(entry.target.getAttribute('data-page-index'));
+                    if (entry.isIntersecting) {
+                        mountedPageIndices.add(idx);
+                    } else {
+                        mountedPageIndices.delete(idx);
+                    }
                 });
-            }
+            },
+            { root: null, rootMargin: '1000px 0px', threshold: 0 }
+        );
+
+        nextTick(() => {
+            const els = containerRef.value?.querySelectorAll('.page-wrapper');
+            els?.forEach((el, i) => {
+                el.setAttribute('data-page-index', i);
+                observer.value.observe(el);
+                visibilityObserver.value.observe(el);
+            });
         });
     };
 
@@ -177,21 +217,16 @@ import ReaderPage from './ReaderPage.vue';
 
     // Fonction pour revenir en haut de la page
     const scrollToTop = () => {
-        console.log('scrollToTop appelée'); // Debug
-
         // Réinitialiser le timer lors du clic
         resetButtonsTimer();
 
         // Stratégie 1: Scroll sur le conteneur direct
         if (containerRef.value) {
-            console.log('containerRef trouvé, scrollTop actuel:', containerRef.value.scrollTop); // Debug
-
             if (containerRef.value.scrollTop > 0) {
                 containerRef.value.scrollTo({
                     top: 0,
                     behavior: 'smooth'
                 });
-                console.log('Scroll sur containerRef effectué'); // Debug
                 return;
             }
         }
@@ -201,7 +236,6 @@ import ReaderPage from './ReaderPage.vue';
         while (currentElement) {
             const styles = window.getComputedStyle(currentElement);
             if (styles.overflowY === 'auto' || styles.overflowY === 'scroll' || currentElement.scrollTop > 0) {
-                console.log('Conteneur avec scroll trouvé:', currentElement.className, 'scrollTop:', currentElement.scrollTop); // Debug
                 currentElement.scrollTo({
                     top: 0,
                     behavior: 'smooth'
@@ -212,7 +246,6 @@ import ReaderPage from './ReaderPage.vue';
         }
 
         // Stratégie 3: Scroll sur la fenêtre entière
-        console.log('Scroll sur window, scrollY actuel:', window.scrollY); // Debug
         window.scrollTo({
             top: 0,
             behavior: 'smooth'
@@ -228,7 +261,8 @@ import ReaderPage from './ReaderPage.vue';
     watch(
         () => props.pages,
         () => {
-            setupIntersectionObserver();
+            mountedPageIndices.clear();
+            setupObservers();
         },
         { immediate: true }
     );
@@ -247,7 +281,7 @@ import ReaderPage from './ReaderPage.vue';
     };
 
     onMounted(() => {
-        setupIntersectionObserver();
+        setupObservers();
 
         // Activer l'auto-hide du header si la largeur < 1200px
         if (windowWidth.value < 1200) {
@@ -267,9 +301,8 @@ import ReaderPage from './ReaderPage.vue';
     });
 
     onUnmounted(() => {
-        if (observer.value) {
-            observer.value.disconnect();
-        }
+        observer.value?.disconnect();
+        visibilityObserver.value?.disconnect();
 
         // Désactiver l'auto-hide du header en quittant
         headerStore.disableAutoHide();
@@ -303,6 +336,12 @@ import ReaderPage from './ReaderPage.vue';
         @apply mb-2 sm:mb-4 px-1 sm:px-4;
     }
 
+    .page-placeholder {
+        @apply w-full;
+        max-width: 1200px;
+        min-height: 400px;
+    }
+
     .loading,
     .error {
         @apply flex items-center justify-center min-h-[400px];
diff --git a/assets/vue/app/domain/reader/presentation/components/ReaderPage.vue b/assets/vue/app/domain/reader/presentation/components/ReaderPage.vue
index 733a2f5..36d88db 100644
--- a/assets/vue/app/domain/reader/presentation/components/ReaderPage.vue
+++ b/assets/vue/app/domain/reader/presentation/components/ReaderPage.vue
@@ -78,6 +78,10 @@ import { useReaderStore } from '../../application/store/readerStore';
             type: String,
             default: 'rotate', // 'rotate', 'scroll', 'normal'
             validator: (value) => ['rotate', 'scroll', 'normal'].includes(value)
+        },
+        windowWidth: {
+            type: Number,
+            default: null
         }
     });
 
@@ -96,8 +100,11 @@ import { useReaderStore } from '../../application/store/readerStore';
     const scrollContainerRef = ref(null);
     const naturalWidth = ref(0);
     const naturalHeight = ref(0);
-    const windowWidth = ref(window.innerWidth);
-    const isMobile = computed(() => windowWidth.value < 768);
+    const localWindowWidth = ref(window.innerWidth);
+    const effectiveWindowWidth = computed(() =>
+        props.windowWidth !== null ? props.windowWidth : localWindowWidth.value
+    );
+    const isMobile = computed(() => effectiveWindowWidth.value < 768);
     const imageLoaded = ref(false);
 
     const imageSource = computed(() => {
@@ -116,17 +123,13 @@ import { useReaderStore } from '../../application/store/readerStore';
         // Utiliser d'abord les dimensions de l'API si disponibles
         if (props.pageData?.dimensions?.width && props.pageData?.dimensions?.height) {
             const ratio = props.pageData.dimensions.width / props.pageData.dimensions.height;
-            const isDouble = ratio > threshold;
-            console.log(`API Dimensions - Page ${props.pageNumber}: ${props.pageData.dimensions.width}x${props.pageData.dimensions.height}, ratio: ${ratio.toFixed(2)}, isDouble: ${isDouble}`);
-            return isDouble;
+            return ratio > threshold;
         }
 
         // Fallback sur les dimensions naturelles de l'image (seulement si l'image est chargée)
         if (imageLoaded.value && naturalWidth.value && naturalHeight.value) {
             const ratio = naturalWidth.value / naturalHeight.value;
-            const isDouble = ratio > threshold;
-            console.log(`Natural Dimensions - Page ${props.pageNumber}: ${naturalWidth.value}x${naturalHeight.value}, ratio: ${ratio.toFixed(2)}, isDouble: ${isDouble}`);
-            return isDouble;
+            return ratio > threshold;
         }
 
         return false;
@@ -137,7 +140,6 @@ import { useReaderStore } from '../../application/store/readerStore';
             naturalWidth.value = imageRef.value.naturalWidth;
             naturalHeight.value = imageRef.value.naturalHeight;
             imageLoaded.value = true;
-            console.log(`Image loaded - Page ${props.pageNumber}: ${naturalWidth.value}x${naturalHeight.value}`);
 
             // Positionner le scroll à droite si c'est le mode scroll
             if (props.doublePageMode === 'scroll' && scrollContainerRef.value) {
@@ -188,7 +190,7 @@ import { useReaderStore } from '../../application/store/readerStore';
 
         if (!width || !height) return null;
 
-        const availableWidth = windowWidth.value;
+        const availableWidth = effectiveWindowWidth.value;
 
         // Si la largeur disponible est < 1200px : utiliser 95% de la largeur
         if (availableWidth < 1200) {
@@ -237,7 +239,7 @@ import { useReaderStore } from '../../application/store/readerStore';
         if (!width || !height) return {};
 
         // En mode rotation : maximiser l'utilisation de l'espace
-        const availableWidth = windowWidth.value;
+        const availableWidth = effectiveWindowWidth.value;
         const availableHeight = window.innerHeight - 100; // Laisser un peu d'espace pour les contrôles
 
         // Après rotation, la largeur originale devient la hauteur affichée
@@ -287,20 +289,18 @@ import { useReaderStore } from '../../application/store/readerStore';
         };
     });
 
-    // Gestion du redimensionnement de la fenêtre
-    const handleResize = () => {
-        windowWidth.value = window.innerWidth;
-    };
+    let ownResizeHandler = null;
 
     onMounted(() => {
-        if (imageRef.value && imageRef.value.complete) {
-            handleImageLoad();
+        if (props.windowWidth === null) {
+            ownResizeHandler = () => { localWindowWidth.value = window.innerWidth; };
+            window.addEventListener('resize', ownResizeHandler, { passive: true });
         }
-        window.addEventListener('resize', handleResize);
+        if (imageRef.value?.complete) handleImageLoad();
     });
 
     onUnmounted(() => {
-        window.removeEventListener('resize', handleResize);
+        if (ownResizeHandler) window.removeEventListener('resize', ownResizeHandler);
     });
 </script>