Add files via upload

comic-book.js

@@ -0,0 +1,40 @@
+export const makeComicBook = ({ entries, loadBlob, getSize }, file) => {
+    const cache = new Map()
+    const urls = new Map()
+    const load = async name => {
+        if (cache.has(name)) return cache.get(name)
+        const src = URL.createObjectURL(await loadBlob(name))
+        const page = URL.createObjectURL(
+            new Blob([`<img src="${src}">`], { type: 'text/html' }))
+        urls.set(name, [src, page])
+        cache.set(name, page)
+        return page
+    }
+    const unload = name => {
+        urls.get(name)?.forEach?.(url => URL.revokeObjectURL(url))
+        urls.delete(name)
+        cache.delete(name)
+    }
+
+    const exts = ['.jpg', '.jpeg', '.png', '.gif', '.bmp', '.webp', '.svg']
+    const files = entries
+        .map(entry => entry.filename)
+        .filter(name => exts.some(ext => name.endsWith(ext)))
+        .sort()
+
+    const book = {}
+    book.getCover = () => loadBlob(files[0])
+    book.metadata = { title: file.name }
+    book.sections = files.map(name => ({
+        id: name,
+        load: () => load(name),
+        unload: () => unload(name),
+        size: getSize(name),
+    }))
+    book.toc = files.map(name => ({ label: name, href: name }))
+    book.rendition = { layout: 'pre-paginated' }
+    book.resolveHref = href => ({ index: book.sections.findIndex(s => s.id === href) })
+    book.splitTOCHref = href => [href, null]
+    book.getTOCFragment = doc => doc.documentElement
+    return book
+}