From ef1159c1398dacd025259511ed55402764511281 Mon Sep 17 00:00:00 2001
From: Rob Watson <rob@netflux.io>
Date: Fri, 4 Sep 2020 13:42:16 +0200
Subject: [PATCH] Add basic file reading functionality

---
 Cargo.toml      | 12 +++++++++
 src/app.rs      |  1 -
 src/canvas.rs   |  8 ++++--
 src/controls.rs | 68 ++++++++++++++++++++++++++++++++++++++++++++-----
 src/home.rs     |  1 -
 src/lib.rs      |  5 ++++
 6 files changed, 85 insertions(+), 10 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index c8ae0b0..041d6d4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,3 +10,15 @@ crate-type = ["cdylib", "rlib"]
 [dependencies]
 yew = "0.17"
 wasm-bindgen = "0.2"
+gloo-events = "0.1.0"
+js-sys = "0.3.44"
+futures = "0.3.5"
+wasm-bindgen-futures = "0.4"
+console_error_panic_hook = "0.1.6"
+
+[dependencies.web-sys]
+version = "0.3.44"
+features = [
+  "console",
+  "AudioContext",
+]
diff --git a/src/app.rs b/src/app.rs
index 601f121..5da0a50 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -1,4 +1,3 @@
-use wasm_bindgen::prelude::*;
 use yew::prelude::*;
 
 use crate::home::Home;
diff --git a/src/canvas.rs b/src/canvas.rs
index 4ccd317..a0ad994 100644
--- a/src/canvas.rs
+++ b/src/canvas.rs
@@ -1,10 +1,14 @@
-use wasm_bindgen::prelude::*;
 use yew::prelude::*;
 
 pub struct Canvas {}
 
+pub enum Msg {
+    Reset,
+    SamplesLoaded,
+}
+
 impl Component for Canvas {
-    type Message = ();
+    type Message = Msg;
     type Properties = ();
 
     fn create(_: Self::Properties, _: ComponentLink<Self>) -> Self {
diff --git a/src/controls.rs b/src/controls.rs
index 9135c92..4107f06 100644
--- a/src/controls.rs
+++ b/src/controls.rs
@@ -1,13 +1,18 @@
-use wasm_bindgen::prelude::*;
+use web_sys::HtmlInputElement;
 use yew::prelude::*;
-use yew::web_sys::console;
+use yew::services::reader::{FileChunk, ReaderTask};
+use yew::services::{ConsoleService, ReaderService};
 
 pub struct Controls {
     link: ComponentLink<Self>,
+    file_input: NodeRef,
+    reader_service: ReaderService,
+    reader_task: Option<ReaderTask>,
 }
 
 pub enum Msg {
     SubmitForm,
+    FileProgress(Option<FileChunk>),
 }
 
 impl Component for Controls {
@@ -15,13 +20,27 @@ impl Component for Controls {
     type Properties = ();
 
     fn create(_: Self::Properties, link: ComponentLink<Self>) -> Self {
-        Self { link }
+        Self {
+            link,
+            file_input: NodeRef::default(),
+            reader_service: ReaderService::new(),
+            reader_task: None,
+        }
     }
 
     fn update(&mut self, msg: Self::Message) -> ShouldRender {
         match msg {
-            Msg::SubmitForm => console::log_1(&"Handle submit form".into()),
-        }
+            Msg::SubmitForm => {
+                if let Err(e) = self.handle_submit_form() {
+                    ConsoleService::error(&e);
+                };
+            }
+            Msg::FileProgress(c) => {
+                if let Err(e) = self.handle_file_progress(c) {
+                    ConsoleService::error(&e);
+                };
+            }
+        };
         true
     }
 
@@ -29,15 +48,52 @@ impl Component for Controls {
         false
     }
 
+    fn rendered(&mut self, _: bool) {}
+
     fn view(&self) -> Html {
         html! {
             <section id="controls" style="width: 800px; height: 100px; border: 1px solid grey">
                 <label>
                     {"Select an audio file"}
-                    <input type="file"/>
+                    <input ref=self.file_input.clone() type="file"/>
                 </label>
                 <button onclick=self.link.callback(move |_| Msg::SubmitForm)>{"Open file"}</button>
             </section>
         }
     }
 }
+
+impl Controls {
+    fn handle_submit_form(&mut self) -> Result<(), String> {
+        let file_input = self
+            .file_input
+            .cast::<HtmlInputElement>()
+            .ok_or("could not cast file_input")?;
+
+        let file_list = file_input.files().ok_or("could not get file list")?;
+        let file = file_list.get(0).ok_or("could not get file")?;
+        let cb = self.link.callback(Msg::FileProgress);
+
+        let task = self
+            .reader_service
+            .read_file_by_chunks(file, cb, 256)
+            .map_err(|e| e.to_string())?;
+
+        self.reader_task = Some(task);
+        Ok(())
+    }
+
+    fn handle_file_progress(&self, chunk: Option<FileChunk>) -> Result<(), String> {
+        match chunk {
+            Some(FileChunk::Started { name, .. }) => {
+                ConsoleService::log(&format!("Started: {}", name))
+            }
+            Some(FileChunk::DataChunk { progress, .. }) => {
+                ConsoleService::log(&format!("Got chunk, progress: {}", progress))
+            }
+            Some(FileChunk::Finished) => ConsoleService::log("Finished"),
+            _ => (),
+        }
+        Ok(())
+    }
+}
diff --git a/src/home.rs b/src/home.rs
index 0b3763f..a2a1088 100644
--- a/src/home.rs
+++ b/src/home.rs
@@ -1,6 +1,5 @@
 use crate::canvas::Canvas;
 use crate::controls::Controls;
-use wasm_bindgen::prelude::*;
 use yew::prelude::*;
 
 pub struct Home {}
diff --git a/src/lib.rs b/src/lib.rs
index ac2c30c..5ee3cf5 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,3 +1,7 @@
+extern crate console_error_panic_hook;
+extern crate js_sys;
+
+use std::panic;
 use wasm_bindgen::prelude::*;
 use yew::prelude::*;
 
@@ -8,5 +12,6 @@ mod home;
 
 #[wasm_bindgen(start)]
 pub fn run_app() {
+    panic::set_hook(Box::new(console_error_panic_hook::hook));
     App::<app::App>::new().mount_to_body();
 }