#748 - Implement methods for processing various media types and prepa… (#772)

* #748 - Implement methods for processing various media types and preparing them for upload

* Various tweaks following code review:
- added blurhash generation
- changed thumbnails to jpeg
- throwing if file size cannot be retrieved
- move MediaProvider files to separate folder so they can cleanly be imported in the NSE
- added audio file processing
- switched all image resizing methods to ImageIO
- various renames

* Fix blurhash formatting issues, `swift-format-ignore-file` doesn't work

* Processing all media within unique folders to avoid conflicts

* Fix various warnings

* Rename `sizeForItemAt(_ url: URL)` to `sizeForItem(at url: URL)`

* Remove unnecessary resizeImage(UIImage) method, start by copying not moving the file to the unique location

* Add back warning for roomDetails.avatarURL

ElementX/Sources/Services/Media/Provider/MediaSourceProxy.swift

@@ -0,0 +1,53 @@
+//
+// Copyright 2022 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Foundation
+import MatrixRustSDK
+
+struct MediaSourceProxy: Hashable {
+    /// The media source provided by Rust.
+    let underlyingSource: MediaSource
+    /// The media's mime type, used when loading the media's file.
+    /// This is optional when loading images and thumbnails in memory.
+    let mimeType: String?
+    
+    init(source: MediaSource, mimeType: String?) {
+        underlyingSource = source
+        self.mimeType = mimeType
+    }
+    
+    init(url: URL, mimeType: String?) {
+        underlyingSource = mediaSourceFromUrl(url: url.absoluteString)
+        self.mimeType = mimeType
+    }
+
+    var url: URL! {
+        // Expecting these to always be valid URLs
+        URL(string: underlyingSource.url())
+    }
+}
+
+// MARK: - Hashable
+
+extension MediaSource: Hashable {
+    public static func == (lhs: MediaSource, rhs: MediaSource) -> Bool {
+        lhs.url() == rhs.url()
+    }
+    
+    public func hash(into hasher: inout Hasher) {
+        hasher.combine(url())
+    }
+}