1 files changed, 46 insertions, 0 deletions

diff --git a/pointless/viewer/presentation.js b/pointless/viewer/presentation.js
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+++ b/pointless/viewer/presentation.js
@@ -0,0 +1,46 @@
+/*
+ * presentation.js
+ * Part of Pointless Viewer, a Beamer presentation viewer
+ * Copyright 2018 Pacien TRAN-GIRARD
+ * License: GNU GPL v3
+ */
+
+"use strict";
+
+class Presentation {
+  constructor(pdf) {
+    this.pdf = pdf;
+    this.currentPageIndex = 1;
+    this.stage = this._setupStage();
+  }
+
+  _setupStage() {
+    var self = this;
+    var onStageReadyCallback = function() { self._onStageReady(); };
+    var onNextCallback = function() { self._onNext(); };
+    var onPreviousCallback = function() { self._onPrevious(); };
+    return new Stage(onStageReadyCallback, onNextCallback, onPreviousCallback);
+  }
+
+  _onStageReady() {
+    this._setPage(this.currentPageIndex);
+  }
+
+  _onNext() {
+    if (this.currentPageIndex === this.pdf.numPages) return;
+    this._setPage(this.currentPageIndex + 1);
+  }
+
+  _onPrevious() {
+    if (this.currentPageIndex === 1) return;
+    this._setPage(this.currentPageIndex - 1);
+  }
+
+  _setPage(pageIndex) {
+    var self = this;
+    this.currentPageIndex = pageIndex;
+    this.pdf.getPage(this.currentPageIndex).then(function(page) {
+      self.stage.setPage(page);
+    })
+  }
+}