1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
use futures::StreamExt;
use serde::{Deserialize, Serialize};
use sha1::Digest as Sha1Digest;
use std::path::PathBuf;
use std::sync::Arc;
use tauri::{Emitter, Window};
use tokio::io::AsyncWriteExt;
use tokio::sync::Semaphore;
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DownloadTask {
pub url: String,
pub path: PathBuf,
#[serde(default)]
pub sha1: Option<String>,
#[serde(default)]
pub sha256: Option<String>,
}
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ProgressEvent {
pub file: String,
pub downloaded: u64,
pub total: u64,
pub status: String, // "Downloading", "Verifying", "Finished", "Error"
}
/// calculate SHA256 hash of data
pub fn compute_sha256(data: &[u8]) -> String {
let mut hasher = sha2::Sha256::new();
hasher.update(data);
hex::encode(hasher.finalize())
}
/// calculate SHA1 hash of data
pub fn compute_sha1(data: &[u8]) -> String {
let mut hasher = sha1::Sha1::new();
hasher.update(data);
hex::encode(hasher.finalize())
}
/// verify file checksum, prefer SHA256, fallback to SHA1
pub fn verify_checksum(data: &[u8], sha256: Option<&str>, sha1: Option<&str>) -> bool {
if let Some(expected) = sha256 {
return compute_sha256(data) == expected;
}
if let Some(expected) = sha1 {
return compute_sha1(data) == expected;
}
// No checksum provided, default to true
true
}
pub async fn download_files(window: Window, tasks: Vec<DownloadTask>) -> Result<(), String> {
let client = reqwest::Client::new();
let semaphore = Arc::new(Semaphore::new(10)); // Max 10 concurrent downloads
// Notify start (total files)
let _ = window.emit("download-start", tasks.len());
let tasks_stream = futures::stream::iter(tasks).map(|task| {
let client = client.clone();
let window = window.clone();
let semaphore = semaphore.clone();
async move {
let _permit = semaphore.acquire().await.unwrap();
let file_name = task.path.file_name().unwrap().to_string_lossy().to_string();
// 1. Check if file exists and verify checksum
if task.path.exists() {
let _ = window.emit(
"download-progress",
ProgressEvent {
file: file_name.clone(),
downloaded: 0,
total: 0,
status: "Verifying".into(),
},
);
if task.sha256.is_some() || task.sha1.is_some() {
if let Ok(data) = tokio::fs::read(&task.path).await {
if verify_checksum(
&data,
task.sha256.as_deref(),
task.sha1.as_deref(),
) {
// Already valid
let _ = window.emit(
"download-progress",
ProgressEvent {
file: file_name.clone(),
downloaded: 0,
total: 0,
status: "Skipped".into(),
},
);
return Ok(());
}
}
}
}
// 2. Download
if let Some(parent) = task.path.parent() {
let _ = tokio::fs::create_dir_all(parent).await;
}
match client.get(&task.url).send().await {
Ok(mut resp) => {
let total_size = resp.content_length().unwrap_or(0);
let mut file = match tokio::fs::File::create(&task.path).await {
Ok(f) => f,
Err(e) => return Err(format!("Create file error: {}", e)),
};
let mut downloaded: u64 = 0;
loop {
match resp.chunk().await {
Ok(Some(chunk)) => {
if let Err(e) = file.write_all(&chunk).await {
return Err(format!("Write error: {}", e));
}
downloaded += chunk.len() as u64;
let _ = window.emit(
"download-progress",
ProgressEvent {
file: file_name.clone(),
downloaded,
total: total_size,
status: "Downloading".into(),
},
);
}
Ok(None) => break,
Err(e) => return Err(format!("Download error: {}", e)),
}
}
}
Err(e) => return Err(format!("Request error: {}", e)),
}
let _ = window.emit(
"download-progress",
ProgressEvent {
file: file_name.clone(),
downloaded: 0,
total: 0,
status: "Finished".into(),
},
);
Ok(())
}
});
// Buffer unordered to run concurrently
tasks_stream
.buffer_unordered(10)
.collect::<Vec<Result<(), String>>>()
.await;
let _ = window.emit("download-complete", ());
Ok(())
}
|