Use IndexedDB to store downloaded files

We probably should delete them at some point 0_0

2 files changed, 112 insertions, 25 deletions

diff --git a/src/cljs/amatus/filestorage.cljs b/src/cljs/amatus/filestorage.cljs
new file mode 100644
index 0000000..7a1d2e4
--- /dev/null
+++ b/src/cljs/amatus/filestorage.cljs
@@ -0,0 +1,92 @@
+;; filestorage.cljs - functions for organizing data
+;; Copyright (C) 2015  David Barksdale <amatus@amatus.name>
+;;
+;; This program is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+;;
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+(ns amatus.filestorage
+  (:require [cljs.core.async :refer [chan close!]])
+  (:require-macros [cljs.core.async.macros :refer [go]]))
+
+(def db (atom nil))
+(let [request (js/indexedDB.open "filestorage" 1)]
+  (set! (.-onupgradeneeded request)
+        (fn [e]
+            (.createObjectStore (.-result (.-target e)) "files"
+                                (js-obj "autoIncrement" true))))
+  (set! (.-onerror request)
+        (fn [e] (js/console.error "Error creating downloads database" e)))
+  (set! (.-onsuccess request)
+        (fn [e] (reset! db (.-result (.-target e))))))
+
+(defn create
+  [type]
+  (let [transaction (.transaction @db (array "files") "readwrite")
+        store (.objectStore transaction "files")
+        blob (js/Blob. (array) (js-obj "type" type))
+        request (.add store blob)
+        ch (chan 1)]
+    (set! (.-onerror request)
+          (fn [e]
+            (js/console.error "add request failed" e)
+            (close! ch)))
+    (set! (.-onsuccess request)
+          (fn [e]
+            (go (>! ch (.-result (.-target e)))
+                (close! ch))))
+    ch))
+
+(defn delete
+  [handle]
+  (let [transaction (.transaction @db (array "files") "readwrite")
+        store (.objectStore transaction "files")
+        request (.delete store handle)]
+    (set! (.-onerror request)
+          (fn [e] (js/console.error "delete request failed" e)))))
+
+(defn write
+  [handle offset data]
+  (let [transaction (.transaction @db (array "files") "readwrite")
+        store (.objectStore transaction "files")
+        request (.get store handle)]
+    (set! (.-onerror request)
+          (fn [e] (js/console.error "get request failed" e)))
+    (set! (.-onsuccess request)
+          (fn [e]
+            (let [blob (.-result (.-target e))
+                  type (.-type blob)
+                  header (.slice blob 0 offset)
+                  trailer (.slice blob (+ offset (.-length data)))
+                  fill (max 0 (- offset (.-size header)))
+                  new-blob (js/Blob. (array header
+                                            (js/Uint8Array. fill)
+                                            data
+                                            trailer)
+                                     (js-obj "type" type))
+                  request (.put store new-blob handle)]
+              (set! (.-onerror request)
+                    (fn [e] (js/console.error "put request failed" e))))))))
+
+(defn create-object-url
+  [handle]
+  (let [transaction (.transaction @db (array "files") "readwrite")
+        store (.objectStore transaction "files")
+        request (.get store handle)
+        ch (chan 1)]
+    (set! (.-onerror request)
+          (fn [e] (js/console.error "get request failed" e)))
+    (set! (.-onsuccess request)
+          (fn [e]
+            (go (>! ch (js/URL.createObjectURL (.-result (.-target e))))
+                (close! ch))))
+    ch))
diff --git a/src/hl/index.cljs.hl b/src/hl/index.cljs.hl
index ad7bda6..a315c12 100644
--- a/src/hl/index.cljs.hl
+++ b/src/hl/index.cljs.hl
@@ -15,7 +15,8 @@
 ;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 (page "index.html"
-      (:require [gnunet-web.core :as core]
+      (:require [amatus.filestorage :as file]
+                [gnunet-web.core :as core]
                 [gnunet-web.extractor :as extractor]
                 [gnunet-web.filesharing :as filesharing]
                 [gnunet-web.hostlist :as hostlist]
@@ -92,30 +93,24 @@
 (defn start-download
   [uri anonymity state-cell progress-cell object-cell]
   (let [download (filesharing/start-download uri anonymity)
-        buffer (js/Uint8Array. (:size download))]
-    (go-loop
-      []
-      (when-let [info (<! (:ch download))]
-        (when (= :download-start (:status info))
-          (reset! state-cell :downloading))
-        (when (= :download-completed (:status info))
-          (reset! object-cell
-                  ;; XXX this needs to be revoked when we're finished
-                  (.createObjectURL
-                    js/URL
-                    (js/Blob. (array buffer)
-                              (js-obj "type" "application/octet-stream"))))
-          (reset! state-cell :complete))
-        (when (zero? (:depth info))
-          (let [offset (:offset info)
-                dst (.subarray buffer
-                               offset
-                               (+ offset (.-length (:data info))))]
-            (.set dst (:data info))))
-        (reset! progress-cell (if (zero? (:size info))
-                                0
-                                (/ (:completed info) (:size info))))
-        (recur)))))
+        file-ch (file/create "application/octet-stream")]
+    (go
+      (let [file-handle (<! file-ch)]
+        (loop []
+          (when-let [info (<! (:ch download))]
+            (when (= :download-start (:status info))
+              (reset! state-cell :downloading))
+            (when (= :download-completed (:status info))
+              (let [object (<! (file/create-object-url file-handle))]
+                ;; XXX this needs to be revoked when we're finished
+                (reset! object-cell object)
+                (reset! state-cell :complete)))
+            (when (zero? (:depth info))
+              (file/write file-handle (:offset info) (:data info)))
+            (reset! progress-cell (if (zero? (:size info))
+                                    0
+                                    (/ (:completed info) (:size info))))
+            (recur)))))))
 
 (defn start-publish
   [keywords metadata file anonymity state-cell progress-cell uri-cell]