feat: show download speed and pause button

core/src/errors.rs

@@ -9,12 +9,14 @@ use crate::deeplink_bridge::PlaceDeeplinkError;
 use super::types::Status;
 
 pub struct FlowError {
+    pub user_title: String,
     pub user_message: String,
 }
 
 impl From<&FlowError> for Status {
     fn from(err: &FlowError) -> Self {
         Self::Error {
+            title: err.user_title.clone(),
             message: err.user_message.clone(),
         }
     }
@@ -132,73 +134,73 @@ impl StepError {
     }
 
     // migrate to json config for i18n later
-    pub fn user_message(&self) -> &str {
+    pub fn user_message(&self) -> (&str, &str) {
         #[allow(clippy::match_same_arms)]
         match self {
             Self::E0000_GENERIC_ERROR {
                 error: _,
                 user_message,
             } => match &user_message {
-                Some(m) => m,
+                Some(m) => ("Generic Error", m),
                 None => {
-                    "Internal communication error during download. Please restart the launcher and try again."
+                    ("Generic Error", "Internal communication error during download. Please restart the launcher and try again.")
                 }
             },
             Self::E1001_FILE_NOT_FOUND { .. } => {
-                "The downloaded file could not be found. Please try downloading again or check your antivirus and disk permissions."
+                ("File Not Found", "The downloaded file could not be found. Please try downloading again or check your antivirus and disk permissions.")
             }
             Self::E1002_CORRUPTED_ARCHIVE { .. } => {
-                "The downloaded file appears to be corrupted. Please try downloading it again."
+                ("Corrupted Archive", "The downloaded file appears to be corrupted. Please try downloading it again.")
             }
             Self::E1003_DECOMPRESS_ACCESS_DENIED { .. } => {
-                "We couldn’t extract the files. Please run the launcher as administrator or check your folder permissions."
+                ("Access Denied", "We couldn’t extract the files. Please run the launcher as administrator or check your folder permissions.")
             }
             Self::E1004_DISK_FULL { .. } => {
-                "There isn’t enough space on your disk to install Decentraland. Please free up some space and try again."
+                ("Disk Full", "There isn’t enough space on your disk to install Decentraland. Please free up some space and try again.")
             }
             Self::E1005_DECOMPRESS_OUT_OF_MEMORY { .. } => {
-                "Your system ran out of memory while installing the game. Try closing other programs or restarting your computer."
+                ("Out of Memory", "Your system ran out of memory while installing the game. Try closing other programs or restarting your computer.")
             }
             Self::E1006_FILE_DELETE_FAILED { .. } => {
-                "We couldn’t remove a previous download. Please check your permissions or try restarting the launcher."
+                ("Delete Failed", "We couldn’t remove a previous download. Please check your permissions or try restarting the launcher.")
             }
             Self::E1007_FILE_CREATE_FAILED { .. } => {
-                "We couldn’t create a file to download. Please check your permissions or try restarting the launcher."
+                ("Create Failed", "We couldn’t create a file to download. Please check your permissions or try restarting the launcher.")
             }
             Self::E2001_DOWNLOAD_FAILED { .. } => {
-                "There was an error while downloading Decentraland. Please check your internet connection and try again."
+                ("Download Failed", "There was an error while downloading Decentraland. Please check your internet connection and try again.")
             }
             Self::E2002_MISSING_CONTENT_LENGTH { .. } => {
-                "Failed to get the file size from the server. Please try again later or verify the download URL is reachable."
+                ("Missing Content-Length", "Failed to get the file size from the server. Please try again later or verify the download URL is reachable.")
             }
             Self::E2003_NETWORK_WRITE_ERROR { .. } => {
-                "There was an error while saving the downloaded file. Please make sure you have enough disk space and permission to write to the folder."
+                ("Network Write Error", "There was an error while saving the downloaded file. Please make sure you have enough disk space and permission to write to the folder.")
             }
             Self::E2004_DOWNLOAD_FAILED_HTTP_CODE { .. } => {
-                "There was an error while downloading Decentraland. Please check your internet connection and try again."
+                ("Download Failed", "There was an error while downloading Decentraland. Please check your internet connection and try again.")
             }
             Self::E2005_DOWNLOAD_FAILED_FILE_INCOMPLETE { .. } => {
-                "Downloading file is incomplete due an error. Please check your internet connection and try again."
+                ("File Incomplete", "Downloading file is incomplete due an error. Please check your internet connection and try again.")
             }
             Self::E2006_DOWNLOAD_FAILED_NETWORK_TIMEOUT => {
-                "Timeout while downloading Decentraland. Please check your internet connection and try again."
+                ("Network Timeout", "Timeout while downloading Decentraland. Please check your internet connection and try again.")
             }
             Self::E3001_OPEN_DEEPLINK_TIMEOUT => {
-                "There was an error while opening the deeplink. Please restart client and try again."
+                ("Deeplink Timeout", "There was an error while opening the deeplink. Please restart client and try again.")
             }
             Self::E3002_PLACE_DEEPLINK_ERROR { .. } => {
-                "There was an error while passing the deeplink. Please restart client and try again."
+                ("Deeplink Error", "There was an error while passing the deeplink. Please restart client and try again.")
             }
             Self::E3003_CANT_GET_VERSION => {
-                "Version data could not be read. Please delete launcher's data folder."
+                ("Can't Get Version", "Version data could not be read. Please delete launcher's data folder.")
             }
         }
     }
 }
 
 impl Display for StepError {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{}", self.user_message())
+        write!(f, "{}", self.user_message().1)
     }
 }
 

core/src/flow.rs

@@ -136,8 +136,10 @@ impl LaunchFlow {
         }
 
         if let Some(e) = last_error {
+            let user_message = e.error.user_message();
             let error = FlowError {
-                user_message: e.error.user_message().to_owned(),
+                user_title: user_message.0.to_owned(),
+                user_message: user_message.1.to_owned(),
             };
             std::result::Result::Err(error)
         } else {
@@ -255,7 +257,9 @@ impl WorkflowStep<LaunchFlowState, ()> for DownloadStep {
         let status = Status::State {
             step: Step::Downloading {
                 progress: 0,
-                build_type: mode,
+                bytes_per_second: 0.0,
+                time_remaining: 0.0,
+                build_type: mode
             },
         };
         Ok(status)

core/src/installs.rs

@@ -33,6 +33,7 @@ use std::time::Duration;
 
 pub mod compression;
 pub mod downloads;
+pub mod download_speed_estimator;
 
 const APP_NAME: &str = "DecentralandLauncherLight";
 const EXPLORER_DOWNLOADED_FILENAME: &str = "decentraland.zip";
@@ -155,7 +156,7 @@ fn get_latest_version(version_data: &Map<String, Value>) -> Result<&str> {
     version_data
         .get("version")
         .and_then(|v| v.as_str())
-        .ok_or_else(|| anyhow!(StepError::E3003_CANT_GET_VERSION.user_message()))
+        .ok_or_else(|| anyhow!(StepError::E3003_CANT_GET_VERSION.user_message().1))
 }
 
 fn get_explorer_launch_path(version: Option<&str>) -> Result<PathBuf> {

core/src/installs/download_speed_estimator.rs

@@ -0,0 +1,60 @@
+// Generated by Claude.
+
+use core::f64;
+use std::time::Duration;
+
+pub struct DownloadSpeedEstimator {
+    /// Smoothed bytes per second (exponential moving average).
+    bytes_per_second: f64,
+    /// EMA smoothing factor in 0..=1. Lower values = smoother.
+    alpha: f64,
+}
+
+impl DownloadSpeedEstimator {
+    /// Create a new estimator.
+    /// `alpha` controls how quickly the estimate reacts to new samples.
+    /// A value around 0.2–0.3 works well for download progress bars.
+    pub const fn new(alpha: f64) -> Self {
+        Self {
+            bytes_per_second: 0.0,
+            alpha: alpha.clamp(0.0, 1.0),
+        }
+    }
+
+    /// Feed a sample of (`bytes_downloaded`, `time_passed`) for the most recent interval.
+    /// `time_passed` is in seconds.
+    pub fn update(&mut self, bytes_downloaded: usize, time_passed: Duration) {
+        if time_passed <= Duration::ZERO {
+            return;
+        }
+
+        #[allow(clippy::cast_precision_loss)]
+        let bytes_downloaded = bytes_downloaded as f64;
+
+        let sample_bps = bytes_downloaded / time_passed.as_secs_f64();
+        if self.bytes_per_second == 0.0 {
+            // First sample — seed the estimate directly.
+            self.bytes_per_second = sample_bps;
+        } else {
+            self.bytes_per_second =
+                sample_bps.mul_add(self.alpha, self.bytes_per_second * (1.0 - self.alpha));
+        }
+    }
+
+    /// Current smoothed bytes-per-second estimate.
+    pub const fn bytes_per_second(&self) -> f64 {
+        self.bytes_per_second
+    }
+
+    /// Estimated milliseconds remaining to download `bytes_remaining`.ß
+    /// Returns `f64::INFINITY` if no speed data is available yet.
+    pub fn time_remaining(&self, bytes_remaining: u64) -> f64 {
+        if self.bytes_per_second <= 0.0 {
+            return f64::INFINITY;
+        }
+
+        #[allow(clippy::cast_precision_loss)]
+        let seconds_remaining = bytes_remaining as f64 / self.bytes_per_second;
+        seconds_remaining * 1000.0
+    }
+}

core/src/installs/downloads.rs

@@ -9,6 +9,7 @@ use std::time::Duration;
 use crate::analytics::Analytics;
 use crate::analytics::event::Event;
 use crate::channel::EventChannel;
+use crate::installs::download_speed_estimator::DownloadSpeedEstimator;
 use crate::types::{BuildType, Status, Step};
 use anyhow::Context;
 use std::sync::Arc;
@@ -113,6 +114,7 @@ pub async fn download_file<T: EventChannel>(
     let duration = std::time::Duration::from_millis(500);
     let mut tasks = Vec::new();
 
+    let mut bytes_per_interval: usize = 0;
     let mut downloaded: u64 = 0;
     {
         let mut file =
@@ -122,12 +124,15 @@ pub async fn download_file<T: EventChannel>(
             })?;
         let mut stream = res.bytes_stream();
 
+        let mut estimator = DownloadSpeedEstimator::new(0.1);
+
         loop {
             match timeout(Duration::from_secs(15), stream.next()).await {
                 Ok(Some(item)) => {
                     let chunk = item?;
                     file.write_all(&chunk)?;
 
+                    bytes_per_interval = bytes_per_interval.saturating_add(chunk.len());
                     let new = min(downloaded.saturating_add(chunk.len() as u64), total_size);
                     downloaded = new;
 
@@ -145,6 +150,8 @@ pub async fn download_file<T: EventChannel>(
                             total_size,
                         ));
                         tasks.push(task);
+                        estimator.update(bytes_per_interval, duration);
+                        bytes_per_interval = 0;
                     }
 
                     #[allow(
@@ -158,6 +165,9 @@ pub async fn download_file<T: EventChannel>(
                     let event: Status = Status::State {
                         step: Step::Downloading {
                             progress,
+                            bytes_per_second: estimator.bytes_per_second(),
+                            time_remaining: estimator
+                                .time_remaining(total_size.saturating_sub(downloaded)),
                             build_type: build_type.clone(),
                         },
                     };

core/src/types.rs

@@ -6,7 +6,7 @@ pub enum Status {
     #[serde(rename_all = "camelCase")]
     State { step: Step },
     #[serde(rename_all = "camelCase")]
-    Error { message: String },
+    Error { title: String, message: String },
 }
 
 #[derive(Clone, Serialize)]
@@ -19,7 +19,13 @@ pub enum Step {
     #[serde(rename_all = "camelCase")]
     Fetching,
     #[serde(rename_all = "camelCase")]
-    Downloading { progress: u8, build_type: BuildType },
+    Downloading {
+        progress: u8,
+        bytes_per_second: f64,
+        /// In milliseconds because that's what JavaScript's `Date` uses.
+        time_remaining: f64,
+        build_type: BuildType
+    },
     #[serde(rename_all = "camelCase")]
     Installing { build_type: BuildType },
     #[serde(rename_all = "camelCase")]
@@ -30,7 +36,12 @@ pub enum Step {
 #[serde(rename_all = "camelCase", tag = "event", content = "data")]
 pub enum LauncherUpdate {
     CheckingForUpdate,
-    Downloading { progress: Option<u8> },
+    Downloading {
+        progress: Option<u8>,
+        bytes_per_second: f64,
+        /// In milliseconds because that's what JavaScript's `Date` uses.
+        time_remaining: Option<f64>
+    },
     DownloadFinished,
     InstallingUpdate,
     RestartingApp,