From d0e9cbcaa6a6f517a1e3995c2bb92af005da96d6 Mon Sep 17 00:00:00 2001
From: ztimson <zaktimson@gmail.com>
Date: Sun, 21 Apr 2024 21:33:38 -0400
Subject: [PATCH] Added download utilities

---
 package.json    |  2 +-
 src/download.ts | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 src/index.ts    |  1 +
 src/xhr.ts      | 18 +-----------------
 4 files changed, 49 insertions(+), 18 deletions(-)
 create mode 100644 src/download.ts

diff --git a/package.json b/package.json
index 207cf92..c995707 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "@ztimson/utils",
-	"version": "0.5.0",
+	"version": "0.6.0",
 	"description": "Utility library",
 	"author": "Zak Timson",
 	"license": "MIT",
diff --git a/src/download.ts b/src/download.ts
new file mode 100644
index 0000000..e1810bc
--- /dev/null
+++ b/src/download.ts
@@ -0,0 +1,46 @@
+import {TypedEmitter, TypedEvents} from './emitter.ts';
+
+export type downloadEvents = TypedEvents & {
+	complete: (blob: Blob) => any;
+	progress: (progress: number) => any;
+}
+
+export function download(href: any, name: string) {
+	const a = document.createElement('a');
+	a.href = href;
+	a.download = name;
+	document.body.appendChild(a);
+	a.click();
+	document.body.removeChild(a);
+}
+
+export function downloadStream(url: string, name?: string) {
+	const emitter = new TypedEmitter<downloadEvents>();
+	fetch(url).then(response => {
+		const contentLength = response.headers.get('Content-Length') || '0';
+		const total = parseInt(contentLength, 10);
+		let chunks: any[] = [], loaded = 0;
+		const reader = response.body?.getReader();
+		reader?.read().then(function processResult(result) {
+			if(result.done) {
+				const blob = new Blob(chunks);
+				emitter.emit('progress', 1);
+				if(name) {
+					const url = URL.createObjectURL(blob);
+					download(url, name);
+					URL.revokeObjectURL(url);
+				}
+				emitter.emit('complete', blob);
+				return;
+			} else {
+				const chunk = result.value;
+				chunks.push(chunk);
+				loaded += chunk.length;
+				const progress = Math.round((loaded / total) * 100);
+				emitter.emit('progress', progress);
+				reader.read().then(processResult);
+			}
+		});
+	});
+	return emitter;
+}
diff --git a/src/index.ts b/src/index.ts
index ba3acb0..bf9ae54 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,5 +1,6 @@
 export * from './array';
 export * from './aset';
+export * from './download.ts';
 export * from './emitter';
 export * from './errors';
 export * from './logger';
diff --git a/src/xhr.ts b/src/xhr.ts
index d70d83c..7fa4132 100644
--- a/src/xhr.ts
+++ b/src/xhr.ts
@@ -1,3 +1,4 @@
+import {TypedEmitter, TypedEvents} from './emitter.ts';
 import {clean} from './objects';
 
 export type Interceptor = (request: Response, next: () => void) => void;
@@ -45,14 +46,6 @@ export class XHR {
 		return () => { this.interceptors[key] = <any>null; }
 	}
 
-	download(opts: RequestOptions & {url: string}) {
-		this.request<Response>({...opts, skipConverting: true}).then(async resp => {
-			const blob = await resp.blob();
-			download(URL.createObjectURL(blob), <string>opts.url.split('/').pop());
-			URL.revokeObjectURL(opts.url);
-		});
-	}
-
 	async request<T>(opts: RequestOptions = {}): Promise<T>  {
 		if(!this.opts.url && !opts.url) throw new Error('URL needs to be set');
 		const url = (opts.url?.startsWith('http') ? opts.url : (this.opts.url || '') + (opts.url || '')).replace(/([^:]\/)\/+/g, '$1');
@@ -82,12 +75,3 @@ export class XHR {
 		});
 	}
 }
-
-export function download(href: any, name: string) {
-	const a = document.createElement('a');
-	a.href = href;
-	a.download = name;
-	document.body.appendChild(a);
-	a.click();
-	document.body.removeChild(a);
-}