From 0f3f8eb016b2dbd94ef609cdc09eaf2e22132e75 Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@gmail.com>
Date: Mon, 13 Oct 2025 19:35:30 +0100
Subject: [PATCH] add tid

---
 src/fs.rs | 35 ++++++++++++++++++++++++++++++-----
 1 file changed, 30 insertions(+), 5 deletions(-)

diff --git a/src/fs.rs b/src/fs.rs
index 351db72..a9a1524 100644
--- a/src/fs.rs
+++ b/src/fs.rs
@@ -1,4 +1,4 @@
-use std::time;
+use std::time::{self, SystemTime, UNIX_EPOCH, Duration};
 
 use atrium_repo::{Repository, blockstore::AsyncBlockStoreRead};
 use futures::StreamExt;
@@ -6,6 +6,27 @@ use indexmap::{IndexMap, IndexSet};
 
 type Inode = usize;
 
+/// Decode a TID (timestamp identifier) to get the timestamp in microseconds since Unix epoch
+fn tid_to_timestamp(tid: &str) -> Option<SystemTime> {
+    const S32_CHAR: &[u8] = b"234567abcdefghijklmnopqrstuvwxyz";
+
+    if tid.len() != 13 {
+        return None;
+    }
+
+    let mut value: u64 = 0;
+    for ch in tid.chars() {
+        let pos = S32_CHAR.iter().position(|&c| c as char == ch)?;
+        // Big-endian: first character is most significant
+        value = (value << 5) | (pos as u64);
+    }
+
+    // Extract timestamp from upper bits (shifted by 10)
+    let micros = value >> 10;
+
+    UNIX_EPOCH.checked_add(Duration::from_micros(micros))
+}
+
 pub struct PdsFs<R> {
     repos: IndexMap<String, Repository<R>>,
     inodes: IndexSet<PdsFsEntry>,
@@ -172,14 +193,18 @@ where
                     .map_or(0, |v| serde_json::to_string(&v).unwrap().len())
                     as u64;
                 let blocks = ((size as u32 + BLKSIZE - 1) / BLKSIZE) as u64;
+
+                // Decode TID to get creation timestamp
+                let timestamp = tid_to_timestamp(&r.rkey).unwrap_or(time::UNIX_EPOCH);
+
                 fuser::FileAttr {
                     ino,
                     size,
                     blocks,
-                    atime: time::UNIX_EPOCH,
-                    mtime: time::UNIX_EPOCH,
-                    ctime: time::UNIX_EPOCH,
-                    crtime: time::UNIX_EPOCH,
+                    atime: timestamp,
+                    mtime: timestamp,
+                    ctime: timestamp,
+                    crtime: timestamp,
                     kind: fuser::FileType::RegularFile,
                     perm: 0o644,
                     nlink: 1,
-- 
2.43.0