allow downloading individual files from bundle

Cargo.lock

@@ -309,12 +309,54 @@ dependencies = [
  "alloc-no-stdlib",
 ]
 
+[[package]]
+name = "askama"
+version = "0.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fb98f10f371286b177db5eeb9a6e5396609555686a35e1d4f7b9a9c6d8af0139"
+dependencies = [
+ "askama_derive",
+ "askama_escape",
+ "askama_shared",
+]
+
+[[package]]
+name = "askama_derive"
+version = "0.11.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87bf87e6e8b47264efa9bde63d6225c6276a52e05e91bf37eaa8afd0032d6b71"
+dependencies = [
+ "askama_shared",
+ "proc-macro2",
+ "syn",
+]
+
 [[package]]
 name = "askama_escape"
 version = "0.10.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "619743e34b5ba4e9703bba34deac3427c72507c7159f5fd030aea8cac0cfe341"
 
+[[package]]
+name = "askama_shared"
+version = "0.12.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf722b94118a07fcbc6640190f247334027685d4e218b794dbfe17c32bf38ed0"
+dependencies = [
+ "askama_escape",
+ "humansize",
+ "mime",
+ "mime_guess",
+ "nom",
+ "num-traits",
+ "percent-encoding",
+ "proc-macro2",
+ "quote",
+ "serde",
+ "syn",
+ "toml",
+]
+
 [[package]]
 name = "atty"
 version = "0.2.14"
@@ -523,6 +565,41 @@ dependencies = [
  "typenum",
 ]
 
+[[package]]
+name = "darling"
+version = "0.13.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a01d95850c592940db9b8194bc39f4bc0e89dee5c4265e4b1807c34a9aba453c"
+dependencies = [
+ "darling_core",
+ "darling_macro",
+]
+
+[[package]]
+name = "darling_core"
+version = "0.13.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "859d65a907b6852c9361e3185c862aae7fafd2887876799fa55f5f99dc40d610"
+dependencies = [
+ "fnv",
+ "ident_case",
+ "proc-macro2",
+ "quote",
+ "strsim",
+ "syn",
+]
+
+[[package]]
+name = "darling_macro"
+version = "0.13.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c972679f83bdf9c42bd905396b6c3588a843a17f0f16dfcfa3e2c5d57441835"
+dependencies = [
+ "darling_core",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "derive_more"
 version = "0.99.17"
@@ -732,12 +809,24 @@ version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c4a1e36c821dbe04574f602848a19f742f4fb3c98d40449f11bcad18d6b17421"
 
+[[package]]
+name = "humansize"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "02296996cb8796d7c6e3bc2d9211b7802812d36999a51bb754123ead7d37d026"
+
 [[package]]
 name = "humantime"
 version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
 
+[[package]]
+name = "ident_case"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
+
 [[package]]
 name = "idna"
 version = "0.2.3"
@@ -879,6 +968,12 @@ dependencies = [
  "unicase",
 ]
 
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
 [[package]]
 name = "miniz_oxide"
 version = "0.5.1"
@@ -921,6 +1016,16 @@ dependencies = [
  "lazy_static",
 ]
 
+[[package]]
+name = "nom"
+version = "7.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8903e5a29a317527874d0402f867152a3d21c908bb0b933e416c65e301d4c36"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
 [[package]]
 name = "ntapi"
 version = "0.3.7"
@@ -930,6 +1035,15 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "num-traits"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "578ede34cf02f8924ab9447f50c28075b4d3e5b269972345e7e0372b38c6cdcd"
+dependencies = [
+ "autocfg",
+]
+
 [[package]]
 name = "num_cpus"
 version = "1.13.1"
@@ -1126,6 +1240,12 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "rustversion"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2cc38e8fa666e2de3c4aba7edeb5ffc5246c1c2ed0e3d17e560aeeba736b23f"
+
 [[package]]
 name = "ryu"
 version = "1.0.9"
@@ -1193,6 +1313,29 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "serde_with"
+version = "1.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b827f2113224f3f19a665136f006709194bdfdcb1fdc1e4b2b5cbac8e0cced54"
+dependencies = [
+ "rustversion",
+ "serde",
+ "serde_with_macros",
+]
+
+[[package]]
+name = "serde_with_macros"
+version = "1.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e182d6ec6f05393cc0e5ed1bf81ad6db3a8feedf8ee515ecdd369809bcce8082"
+dependencies = [
+ "darling",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "sha-1"
 version = "0.10.0"
@@ -1257,6 +1400,12 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "strsim"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "73473c0e59e6d5812c5dfe2a064a6444949f089e20eec9a2e5506596494e4623"
+
 [[package]]
 name = "subtle"
 version = "2.4.1"
@@ -1381,6 +1530,15 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "toml"
+version = "0.5.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8d82e1a7758622a465f8cee077614c73484dac5b836c02ff6a40d5d1010324d7"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "tracing"
 version = "0.1.34"
@@ -1423,6 +1581,7 @@ dependencies = [
  "actix-http",
  "actix-web",
  "actix-web-actors",
+ "askama",
  "bytes",
  "bytesize",
  "crc32fast",
@@ -1438,6 +1597,7 @@ dependencies = [
  "sanitise-file-name",
  "serde",
  "serde_json",
+ "serde_with",
  "thiserror",
  "time",
  "tokio",

Cargo.toml

@@ -13,6 +13,7 @@ actix-files = "0.6.0"
 actix-http = "3.0.4"
 actix-web = "4.0.1"
 actix-web-actors = "4.1.0"
+askama = "0.11.1"
 bytes = "1.1.0"
 bytesize = "1.1.0"
 crc32fast = "1.3.2"
@@ -28,6 +29,7 @@ rand = "0.8.5"
 sanitise-file-name = "1.0.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
+serde_with = "1.13.0"
 thiserror = "1"
 time = "0.3.9"
 tokio = { version = "1.17.0", features = ["full"] }

README.md

@@ -15,6 +15,7 @@
   sender has gone offline
 - Easy to send multiple files at once - they're bundled into a zip
   file for receivers, with zero compression so extraction is quick
+- Can also download individual files out of an uploaded collection
 - Sanitises filenames, using sensible non-obnoxious defaults that
   should be safe across platforms
 - Rudimentary password authentication for uploading files

src/download.rs

@@ -1,3 +1,4 @@
+use core::fmt;
 use std::{
     cmp,
     fs::File,
@@ -14,6 +15,8 @@ use futures_core::{ready, Stream};
 use inotify::{Inotify, WatchMask};
 use log::trace;
 use pin_project_lite::pin_project;
+use serde::{de, Deserialize, Deserializer};
+use time::OffsetDateTime;
 use std::{os::unix::fs::MetadataExt, time::SystemTime};
 
 use actix_web::{
@@ -30,7 +33,55 @@ use actix_web::{
 
 use actix_files::HttpRange;
 
-use crate::store::StoredFile;
+use crate::{store::StoredFile, upload::UploadedFile};
+
+#[derive(Clone, Copy)]
+pub enum DownloadSelection {
+    One(usize),
+    All,
+}
+
+impl fmt::Display for DownloadSelection {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            DownloadSelection::All => write!(f, "all"),
+            DownloadSelection::One(n) => n.fmt(f),
+        }
+    }
+}
+
+struct SelectionVisitor;
+
+impl<'de> de::Visitor<'de> for SelectionVisitor {
+    type Value = DownloadSelection;
+
+    fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(formatter, r#"a nonnegative integer or the string "all""#)
+    }
+
+    fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E> {
+        Ok(DownloadSelection::One(v as usize))
+    }
+
+    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+    where E: de::Error {
+        if v == "all" {
+            Ok(DownloadSelection::All)
+        } else if let Ok(n) = v.parse::<usize>() {
+            Ok(DownloadSelection::One(n))
+        } else {
+            Err(de::Error::invalid_value(de::Unexpected::Str(v), &self))
+        }
+    }
+}
+
+impl<'de> Deserialize<'de> for DownloadSelection {
+    fn deserialize<D: Deserializer<'de>>(
+        de: D
+    ) -> Result<DownloadSelection, D::Error> {
+        de.deserialize_any(SelectionVisitor)
+    }
+}
 
 // This is copied substantially from actix-files, with some tweaks
 
@@ -38,24 +89,64 @@ pub(crate) struct DownloadingFile {
     pub(crate) file: File,
     pub(crate) storage_path: PathBuf,
     pub(crate) info: StoredFile,
+    pub(crate) selection: DownloadSelection,
 }
 
 impl DownloadingFile {
+    fn selected(&self) -> Option<&UploadedFile> {
+        match self.selection {
+            DownloadSelection::All => None,
+            DownloadSelection::One(n) => Some(self.info.contents.as_ref()?.get(n)?),
+        }
+    }
+
+    fn name(&self) -> &str {
+        match self.selected() {
+            None => &self.info.name,
+            Some(f) => &f.name,
+        }
+    }
+
+    fn size(&self) -> u64 {
+        match self.selected() {
+            None => self.info.size,
+            Some(f) => f.size,
+        }
+    }
+
+    fn modtime(&self) -> OffsetDateTime {
+        match self.selected() {
+            None => self.info.modtime,
+            Some(f) => f.modtime,
+        }
+    }
+
+    fn baseline_offset(&self) -> u64 {
+        if let (DownloadSelection::One(n), Some(files)) = (self.selection, self.info.contents.as_ref()) {
+            crate::zip::file_data_offset(&files, n)
+        } else {
+            0
+        }
+    }
+
     fn etag(&self) -> EntityTag {
         let ino = self.file.metadata().map(|md| md.ino()).unwrap_or_default();
+        let modtime = self.modtime();
         EntityTag::new_strong(format!(
-            "{:x}:{:x}:{:x}:{:x}",
+            "{:x}:{}:{:x}:{:x}:{:x}",
             ino,
-            self.info.size,
+            self.selection,
-            self.info.modtime.unix_timestamp() as u64,
+            self.size(),
-            self.info.modtime.nanosecond(),
+            modtime.unix_timestamp() as u64,
+            modtime.nanosecond(),
         ))
     }
 
     /// Creates an `HttpResponse` with file as a streaming body.
     pub fn into_response(self, req: &HttpRequest) -> HttpResponse<BoxBody> {
+        let total_size = self.size();
         let etag = self.etag();
-        let last_modified = HttpDate::from(SystemTime::from(self.info.modtime));
+        let last_modified = HttpDate::from(SystemTime::from(self.modtime()));
 
         let precondition_failed = precondition_failed(req, &etag, &last_modified);
         let not_modified = not_modified(req, &etag, &last_modified);
@@ -68,14 +159,14 @@ impl DownloadingFile {
             header::CONTENT_DISPOSITION,
             ContentDisposition {
                 disposition: DispositionType::Attachment,
-                parameters: vec![DispositionParam::Filename(self.info.name)],
+                parameters: vec![DispositionParam::Filename(self.name().to_string())],
             },
         ));
         res.insert_header((header::LAST_MODIFIED, last_modified));
         res.insert_header((header::ETAG, etag));
         res.insert_header((header::ACCEPT_RANGES, "bytes"));
 
-        let mut length = self.info.size;
+        let mut length = total_size;
         let mut offset = 0;
 
         // check for range header
@@ -97,7 +188,7 @@ impl DownloadingFile {
                             "bytes {}-{}/{}",
                             offset,
                             offset + length - 1,
-                            self.info.size
+                            total_size,
                         ),
                     ));
                 } else {
@@ -118,9 +209,9 @@ impl DownloadingFile {
                 .map_into_boxed_body();
         }
 
-        let reader = new_live_reader(length, offset, self.file, self.storage_path);
+        let reader = new_live_reader(length, self.baseline_offset() + offset, self.file, self.storage_path);
 
-        if offset != 0 || length != self.info.size {
+        if offset != 0 || length != total_size {
             res.status(StatusCode::PARTIAL_CONTENT);
         }
 

src/main.rs

@@ -1,9 +1,10 @@
 mod download;
 mod store;
+mod timestamp;
 mod upload;
 mod zip;
 
-use std::{fmt::Debug, fs::File, path::PathBuf, str::FromStr};
+use std::{fmt::Debug, path::PathBuf, str::FromStr};
 
 use actix_files::NamedFile;
 use actix_web::{
@@ -11,11 +12,12 @@ use actix_web::{
     HttpServer, Responder,
 };
 use actix_web_actors::ws;
+use askama::Template;
 use bytesize::ByteSize;
 use log::{error, warn};
 use serde::{Deserialize, Serialize};
-use store::FileStore;
+use store::{FileStore, StoredFile};
-use tokio::sync::RwLock;
+use tokio::{fs::File, sync::RwLock};
 
 const APP_NAME: &str = "transbeam";
 
@@ -49,9 +51,19 @@ pub fn log_auth_failure(ip_addr: &str) {
     warn!("Incorrect authentication attempt from {}", ip_addr);
 }
 
+
 #[derive(Deserialize)]
 struct DownloadRequest {
     code: String,
+    download: Option<download::DownloadSelection>,
+}
+
+#[derive(Template)]
+#[template(path = "download.html")]
+struct DownloadInfo<'a> {
+    file: StoredFile,
+    code: &'a str,
+    available: u64,
 }
 
 #[get("/download")]
@@ -62,29 +74,52 @@ async fn handle_download(
 ) -> actix_web::Result<HttpResponse> {
     let code = &download.code;
     if !store::is_valid_storage_code(code) {
-        return download_not_found(req, data);
+        return not_found(req, data, true);
     }
     let info = data.file_store.read().await.lookup_file(code);
-    if let Some(info) = info {
+    let info = if let Some(i) = info {
-        let storage_path = data.config.storage_dir.join(code);
+        i
-        let file = File::open(&storage_path)?;
+    } else {
+        return not_found(req, data, true)
+    };
+
+    let storage_path = data.config.storage_dir.join(code);
+    let file = File::open(&storage_path).await?;
+    if let Some(selection) = download.download {
+        if let download::DownloadSelection::One(n) = selection {
+            if let Some(ref files) = info.contents {
+                if n >= files.len() {
+                    return not_found(req, data, false);
+                }
+            } else {
+                return not_found(req, data, false);
+            }
+        }
         Ok(download::DownloadingFile {
-            file,
+            file: file.into_std().await,
             storage_path,
             info,
+            selection,
         }
-        .into_response(&req))
+           .into_response(&req))
     } else {
-        download_not_found(req, data)
+        Ok(HttpResponse::Ok().body(DownloadInfo {
+            file: info,
+            code,
+            available: file.metadata().await?.len(),
+        }.render().unwrap()))
     }
 }
 
-fn download_not_found(
+fn not_found(
     req: HttpRequest,
     data: web::Data<AppState>,
+    report: bool,
 ) -> actix_web::Result<HttpResponse> {
-    let ip_addr = get_ip_addr(&req, data.config.reverse_proxy);
+    if report {
-    log_auth_failure(&ip_addr);
+        let ip_addr = get_ip_addr(&req, data.config.reverse_proxy);
+        log_auth_failure(&ip_addr);
+    }
     Ok(NamedFile::open(data.config.static_dir.join("404.html"))?
         .set_status_code(StatusCode::NOT_FOUND)
         .into_response(&req))

src/store.rs

@@ -10,12 +10,15 @@ use rand::{
     thread_rng, Rng,
 };
 use serde::{Deserialize, Serialize};
+use serde_with::skip_serializing_none;
 use time::OffsetDateTime;
 use tokio::{
     fs::File,
     io::{AsyncReadExt, AsyncWriteExt},
 };
 
+use crate::upload::UploadedFile;
+
 const STATE_FILE_NAME: &str = "files.json";
 const MAX_STORAGE_FILES: usize = 1024;
 
@@ -33,55 +36,16 @@ pub fn is_valid_storage_code(s: &str) -> bool {
         .all(|c| c.is_ascii_alphanumeric() || c == &b'-')
 }
 
+#[skip_serializing_none]
 #[derive(Clone, Deserialize, Serialize)]
 pub struct StoredFile {
     pub name: String,
     pub size: u64,
-    #[serde(with = "timestamp")]
+    #[serde(with = "crate::timestamp")]
     pub modtime: OffsetDateTime,
-    #[serde(with = "timestamp")]
+    #[serde(with = "crate::timestamp")]
     pub expiry: OffsetDateTime,
-}
+    pub contents: Option<Vec<UploadedFile>>,
-
-pub(crate) mod timestamp {
-    use core::fmt;
-
-    use serde::{de::Visitor, Deserializer, Serializer};
-    use time::OffsetDateTime;
-
-    pub(crate) fn serialize<S: Serializer>(
-        time: &OffsetDateTime,
-        ser: S,
-    ) -> Result<S::Ok, S::Error> {
-        ser.serialize_i64(time.unix_timestamp())
-    }
-
-    struct I64Visitor;
-
-    impl<'de> Visitor<'de> for I64Visitor {
-        type Value = i64;
-
-        fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
-            write!(formatter, "an integer")
-        }
-
-        fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E> {
-            Ok(v)
-        }
-
-        fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E> {
-            Ok(v as i64)
-        }
-    }
-
-    pub(crate) fn deserialize<'de, D: Deserializer<'de>>(
-        de: D,
-    ) -> Result<OffsetDateTime, D::Error> {
-        Ok(
-            OffsetDateTime::from_unix_timestamp(de.deserialize_i64(I64Visitor)?)
-                .unwrap_or_else(|_| OffsetDateTime::now_utc()),
-        )
-    }
 }
 
 async fn is_valid_entry(key: &str, info: &StoredFile, storage_dir: &Path) -> bool {

src/timestamp.rs

@@ -0,0 +1,38 @@
+use core::fmt;
+
+use serde::{de::Visitor, Deserializer, Serializer};
+use time::OffsetDateTime;
+
+pub(crate) fn serialize<S: Serializer>(
+    time: &OffsetDateTime,
+    ser: S,
+) -> Result<S::Ok, S::Error> {
+    ser.serialize_i64(time.unix_timestamp())
+}
+
+struct I64Visitor;
+
+impl<'de> Visitor<'de> for I64Visitor {
+    type Value = i64;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        write!(formatter, "an integer")
+    }
+
+    fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E> {
+        Ok(v)
+    }
+
+    fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E> {
+        Ok(v as i64)
+    }
+}
+
+pub(crate) fn deserialize<'de, D: Deserializer<'de>>(
+    de: D,
+) -> Result<OffsetDateTime, D::Error> {
+    Ok(
+        OffsetDateTime::from_unix_timestamp(de.deserialize_i64(I64Visitor)?)
+            .unwrap_or_else(|_| OffsetDateTime::now_utc()),
+    )
+}

src/upload.rs

@@ -93,9 +93,11 @@ impl Actor for Uploader {
 
 type Context = <Uploader as Actor>::Context;
 
+#[derive(Clone, Deserialize, Serialize)]
 pub struct UploadedFile {
     pub name: String,
     pub size: u64,
+    #[serde(with = "crate::timestamp")]
     pub modtime: OffsetDateTime,
 }
 
@@ -273,7 +275,7 @@ impl Uploader {
                 let (writer, name, size, modtime): (Box<dyn Write>, _, _, _) = if files.len() > 1 {
                     info!("Wrapping in zipfile generator");
                     let now = OffsetDateTime::now_utc();
-                    let zip_writer = super::zip::ZipGenerator::new(files, writer);
+                    let zip_writer = super::zip::ZipGenerator::new(files.clone(), writer);
                     let size = zip_writer.total_size();
                     let download_filename = super::APP_NAME.to_owned()
                         + &now.format(FILENAME_DATE_FORMAT).unwrap()
@@ -293,6 +295,7 @@ impl Uploader {
                     size,
                     modtime,
                     expiry: OffsetDateTime::now_utc() + lifetime * time::Duration::DAY,
+                    contents: if files.len() > 1 { Some(files) } else { None },
                 };
                 let state = self.app_state.clone();
                 let storage_filename = self.storage_filename.clone();

src/zip.rs

@@ -37,6 +37,12 @@ fn file_entries_size(files: &[UploadedFile]) -> u64 {
     total
 }
 
+pub fn file_data_offset(files: &[UploadedFile], idx: usize) -> u64 {
+    file_entries_size(&files[..idx])
+        + LOCAL_HEADER_SIZE_MINUS_FILENAME
+        + files[idx].name.len() as u64
+}
+
 fn central_directory_size(files: &[UploadedFile]) -> u64 {
     let mut total = 0;
     for file in files.iter() {

static/css/transbeam.css

@@ -127,6 +127,18 @@ td {
     padding: 10px;
 }
 
+td.file_unavailable {
+    display: none;
+}
+
+tr.unavailable td.file_unavailable {
+    display: revert;
+}
+
+tr.unavailable td.file_download {
+    display: none;
+}
+
 .delete_button {
     background-color: #888;
     mask-image: url("../images/feather-icons/x.svg");
@@ -142,6 +154,75 @@ td {
     background-color: #f00;
 }
 
+#download_toplevel {
+    font-size: 24px;
+}
+
+#download_toplevel div {
+    margin-top: 5px;
+    margin-bottom: 5px;
+}
+
+#download_toplevel .file_name {
+    font-weight: 500;
+}
+
+#download_toplevel .file_download {
+    width: 75px;
+    height: 75px;
+    margin-left: auto;
+    margin-right: auto;
+}
+
+#download_contents h3 {
+    margin-bottom: 0;
+}
+
+#download_contents table {
+    margin-top: 0;
+}
+
+.file_download {
+    position: relative;
+}
+
+.file_download .download_button {
+    position: absolute;
+    top: 0;
+    bottom: 0;
+    left: 0;
+    right: 0;
+}
+
+td.file_download {
+    padding: 15px;
+}
+
+.download_button {
+    background-color: #33f;
+    mask-image: url("../images/feather-icons/download.svg");
+    mask-size: contain;
+    mask-repeat: no-repeat;
+    mask-position: center;
+    padding-left: 15px;
+    padding-right: 15px;
+    cursor: pointer;
+}
+
+.download_button:hover {
+    background-color: #00b;
+}
+
+.file_unavailable {
+    background-color: #999;
+    mask-image: url("../images/feather-icons/clock.svg");
+    mask-size: contain;
+    mask-repeat: no-repeat;
+    mask-position: center;
+    padding-left: 15px;
+    padding-right: 15px;
+}
+
 td.file_size {
     text-align: right;
 }
@@ -162,6 +243,7 @@ button, .fake_button, input[type="submit"] {
     border-radius: 4px;
     padding: 6px 12px;
     cursor: pointer;
+    text-decoration: none;
 }
 
 button:hover, .fake_button:hover, input[type="submit"]:hover {

static/images/feather-icons/clock.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-clock"><circle cx="12" cy="12" r="10"></circle><polyline points="12 6 12 12 16 14"></polyline></svg>

static/images/feather-icons/download.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-download"><path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"></path><polyline points="7 10 12 15 17 10"></polyline><line x1="12" y1="15" x2="12" y2="3"></line></svg>

static/index.html

@@ -8,7 +8,7 @@
     <link rel="apple-touch-icon" href="images/site-icons/transbeam-apple.png"/>
     <link rel="manifest" href="manifest.json"/>
     <script src="js/util.js"></script>
-    <script src="js/download.js"></script>
+    <script src="js/download-landing.js"></script>
     <script src="js/upload.js"></script>
     <title>transbeam</title>
   </head>

templates/download.html

@@ -0,0 +1,46 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8"/>
+    <meta name="viewport" content="width=device-width, initial-scale=1"/>
+    <link rel="stylesheet" type="text/css" href="css/transbeam.css"/>
+    <link rel="stylesheet" type="text/css" href="css/download.css"/>
+    <link rel="apple-touch-icon" href="images/site-icons/transbeam-apple.png"/>
+    <link rel="manifest" href="manifest.json"/>
+    <script src="js/util.js"></script>
+    <script src="js/download.js"></script>
+    <title>{{ file.name }} - transbeam</title>
+  </head>
+  <body>
+    <div id="header">
+      <img src="images/site-icons/transbeam.svg" height="128">
+      <h1>transbeam</h1>
+    </div>
+    <div id="download_toplevel" class="section">
+      <div class="file_name">{{ file.name }}</div>
+      <div class="file_size">{{ bytesize::to_string(file.size.clone(), false).replace(" ", "") }}</div>
+      <div class="file_download"><a class="download_button" href="download?code={{ code }}&download=all"></a></div>
+    </div>
+    {% match file.contents %}
+      {% when Some with (files) %}
+        <div id="download_contents" class="section">
+          <h3>Contents</h3>
+          <table>
+            {% for f in files %}
+              <tr class="{% if zip::file_data_offset(files.as_ref(), loop.index0.clone()) > available %}unavailable{% endif %}">
+                <td class="file_size">{{ bytesize::to_string(f.size.clone(), false).replace(" ", "") }}</td>
+                <td class="file_name">{{ f.name }}</td>
+                <td class="file_download"><a class="download_button" href="download?code={{ code }}&download={{ loop.index0 }}"></a></td>
+                <td class="file_unavailable"></td>
+              </tr>
+            {% endfor %}
+          </table>
+        </div>
+      {% else %}
+    {% endmatch %}
+    <div id="footer">
+      <h5>(c) 2022 xenofem, MIT licensed</h5>
+      <h5><a target="_blank" href="https://git.xeno.science/xenofem/transbeam">source</a></h5>
+    </div>
+  </body>
+</html>