refactor: Move everything into src-tauri

Signed-off-by: quexeky <git@quexeky.dev>

src-tauri/games/src/downloads/download_logic.rs

@@ -0,0 +1,295 @@
+use std::fs::{Permissions, set_permissions};
+use std::io::Read;
+#[cfg(unix)]
+use std::os::unix::fs::PermissionsExt;
+use std::sync::Arc;
+use std::time::Instant;
+use std::{
+    fs::{File, OpenOptions},
+    io::{self, BufWriter, Seek, SeekFrom, Write},
+    path::PathBuf,
+};
+
+use download_manager::error::ApplicationDownloadError;
+use download_manager::util::download_thread_control_flag::{
+    DownloadThreadControl, DownloadThreadControlFlag,
+};
+use download_manager::util::progress_object::ProgressHandle;
+use log::{debug, info, warn};
+use md5::{Context, Digest};
+use remote::auth::generate_authorization_header;
+use remote::error::{DropServerError, RemoteAccessError};
+use remote::requests::generate_url;
+use remote::utils::DROP_CLIENT_SYNC;
+use reqwest::blocking::Response;
+
+use crate::downloads::manifest::{ChunkBody, DownloadBucket, DownloadContext, DownloadDrop};
+
+static MAX_PACKET_LENGTH: usize = 4096 * 4;
+static BUMP_SIZE: usize = 4096 * 16;
+
+pub struct DropWriter<W: Write> {
+    hasher: Context,
+    destination: BufWriter<W>,
+    progress: ProgressHandle,
+}
+impl DropWriter<File> {
+    fn new(path: PathBuf, progress: ProgressHandle) -> Result<Self, io::Error> {
+        let destination = OpenOptions::new()
+            .write(true)
+            .create(true)
+            .truncate(false)
+            .open(&path)?;
+        Ok(Self {
+            destination: BufWriter::with_capacity(1024 * 1024, destination),
+            hasher: Context::new(),
+            progress,
+        })
+    }
+
+    fn finish(mut self) -> io::Result<Digest> {
+        self.flush()?;
+        Ok(self.hasher.finalize())
+    }
+}
+// Write automatically pushes to file and hasher
+impl Write for DropWriter<File> {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        self.hasher
+            .write_all(buf)
+            .map_err(|e| io::Error::other(format!("Unable to write to hasher: {e}")))?;
+        let bytes_written = self.destination.write(buf)?;
+        self.progress.add(bytes_written);
+
+        Ok(bytes_written)
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        self.hasher.flush()?;
+        self.destination.flush()
+    }
+}
+// Seek moves around destination output
+impl Seek for DropWriter<File> {
+    fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
+        self.destination.seek(pos)
+    }
+}
+
+pub struct DropDownloadPipeline<'a, R: Read, W: Write> {
+    pub source: R,
+    pub drops: Vec<DownloadDrop>,
+    pub destination: Vec<DropWriter<W>>,
+    pub control_flag: &'a DownloadThreadControl,
+    #[allow(dead_code)]
+    progress: ProgressHandle,
+}
+
+impl<'a> DropDownloadPipeline<'a, Response, File> {
+    fn new(
+        source: Response,
+        drops: Vec<DownloadDrop>,
+        control_flag: &'a DownloadThreadControl,
+        progress: ProgressHandle,
+    ) -> Result<Self, io::Error> {
+        Ok(Self {
+            source,
+            destination: drops
+                .iter()
+                .map(|drop| DropWriter::new(drop.path.clone(), progress.clone()))
+                .try_collect()?,
+            drops,
+            control_flag,
+            progress,
+        })
+    }
+
+    fn copy(&mut self) -> Result<bool, io::Error> {
+        let mut copy_buffer = [0u8; MAX_PACKET_LENGTH];
+        for (index, drop) in self.drops.iter().enumerate() {
+            let destination = self
+                .destination
+                .get_mut(index)
+                .ok_or(io::Error::other("no destination"))?;
+            let mut remaining = drop.length;
+            if drop.start != 0 {
+                destination.seek(SeekFrom::Start(drop.start as u64))?;
+            }
+            let mut last_bump = 0;
+            loop {
+                let size = MAX_PACKET_LENGTH.min(remaining);
+                let size = self
+                    .source
+                    .read(&mut copy_buffer[0..size])
+                    .inspect_err(|_| {
+                        info!("got error from {}", drop.filename);
+                    })?;
+                remaining -= size;
+                last_bump += size;
+
+                destination.write_all(&copy_buffer[0..size])?;
+
+                if last_bump > BUMP_SIZE {
+                    last_bump -= BUMP_SIZE;
+                    if self.control_flag.get() == DownloadThreadControlFlag::Stop {
+                        return Ok(false);
+                    }
+                }
+
+                if remaining == 0 {
+                    break;
+                };
+            }
+
+            if self.control_flag.get() == DownloadThreadControlFlag::Stop {
+                return Ok(false);
+            }
+        }
+
+        Ok(true)
+    }
+
+    #[allow(dead_code)]
+    fn debug_skip_checksum(self) {
+        self.destination
+            .into_iter()
+            .for_each(|mut e| e.flush().unwrap());
+    }
+
+    fn finish(self) -> Result<Vec<Digest>, io::Error> {
+        let checksums = self
+            .destination
+            .into_iter()
+            .map(|e| e.finish())
+            .try_collect()?;
+        Ok(checksums)
+    }
+}
+
+pub fn download_game_bucket(
+    bucket: &DownloadBucket,
+    ctx: &DownloadContext,
+    control_flag: &DownloadThreadControl,
+    progress: ProgressHandle,
+) -> Result<bool, ApplicationDownloadError> {
+    // If we're paused
+    if control_flag.get() == DownloadThreadControlFlag::Stop {
+        progress.set(0);
+        return Ok(false);
+    }
+
+    let start = Instant::now();
+
+    let header = generate_authorization_header();
+
+    let url = generate_url(&["/api/v2/client/chunk"], &[])
+        .map_err(ApplicationDownloadError::Communication)?;
+
+    let body = ChunkBody::create(ctx, &bucket.drops);
+
+    let response = DROP_CLIENT_SYNC
+        .post(url)
+        .json(&body)
+        .header("Authorization", header)
+        .send()
+        .map_err(|e| ApplicationDownloadError::Communication(e.into()))?;
+
+    if response.status() != 200 {
+        info!("chunk request got status code: {}", response.status());
+        let raw_res = response.text().map_err(|e| {
+            ApplicationDownloadError::Communication(RemoteAccessError::FetchError(e.into()))
+        })?;
+        info!("{raw_res}");
+        if let Ok(err) = serde_json::from_str::<DropServerError>(&raw_res) {
+            return Err(ApplicationDownloadError::Communication(
+                RemoteAccessError::InvalidResponse(err),
+            ));
+        }
+        return Err(ApplicationDownloadError::Communication(
+            RemoteAccessError::UnparseableResponse(raw_res),
+        ));
+    }
+
+    let lengths = response
+        .headers()
+        .get("Content-Lengths")
+        .ok_or(ApplicationDownloadError::Communication(
+            RemoteAccessError::UnparseableResponse("missing Content-Lengths header".to_owned()),
+        ))?
+        .to_str()
+        .map_err(|e| {
+            ApplicationDownloadError::Communication(RemoteAccessError::UnparseableResponse(
+                e.to_string(),
+            ))
+        })?;
+
+    for (i, raw_length) in lengths.split(",").enumerate() {
+        let length = raw_length.parse::<usize>().unwrap_or(0);
+        let Some(drop) = bucket.drops.get(i) else {
+            warn!("invalid number of Content-Lengths recieved: {i}, {lengths}");
+            return Err(ApplicationDownloadError::DownloadError(
+                RemoteAccessError::InvalidResponse(DropServerError {
+                    status_code: 400,
+                    status_message: format!(
+                        "invalid number of Content-Lengths recieved: {i}, {lengths}"
+                    ),
+                }),
+            ));
+        };
+        if drop.length != length {
+            warn!(
+                "for {}, expected {}, got {} ({})",
+                drop.filename, drop.length, raw_length, length
+            );
+            return Err(ApplicationDownloadError::DownloadError(
+                RemoteAccessError::InvalidResponse(DropServerError {
+                    status_code: 400,
+                    status_message: format!(
+                        "for {}, expected {}, got {} ({})",
+                        drop.filename, drop.length, raw_length, length
+                    ),
+                }),
+            ));
+        }
+    }
+
+    let timestep = start.elapsed().as_millis();
+
+    debug!("took {}ms to start downloading", timestep);
+
+    let mut pipeline =
+        DropDownloadPipeline::new(response, bucket.drops.clone(), control_flag, progress)
+            .map_err(|e| ApplicationDownloadError::IoError(Arc::new(e)))?;
+
+    let completed = pipeline
+        .copy()
+        .map_err(|e| ApplicationDownloadError::IoError(Arc::new(e)))?;
+    if !completed {
+        return Ok(false);
+    }
+
+    // If we complete the file, set the permissions (if on Linux)
+    #[cfg(unix)]
+    {
+        for drop in bucket.drops.iter() {
+            let permissions = Permissions::from_mode(drop.permissions);
+            set_permissions(drop.path.clone(), permissions)
+                .map_err(|e| ApplicationDownloadError::IoError(Arc::new(e)))?;
+        }
+    }
+
+    let checksums = pipeline
+        .finish()
+        .map_err(|e| ApplicationDownloadError::IoError(Arc::new(e)))?;
+
+    for (index, drop) in bucket.drops.iter().enumerate() {
+        let res = hex::encode(**checksums.get(index).unwrap());
+        if res != drop.checksum {
+            warn!("context didn't match... doing nothing because we will validate later.");
+            // return Ok(false);
+            // return Err(ApplicationDownloadError::Checksum);
+        }
+    }
+
+    Ok(true)
+}