feat: index command defaults to ALL drives

Changed behavior:
- No --drive/--drives: indexes ALL available NTFS drives
- --drive C: indexes only C:
- --drives C,D,E: indexes C:, D:, E:

The output path now only determines WHERE to save the index,
not WHICH drives to index. This matches the search command
behavior which also defaults to all drives.

Author: githubrobbi

Cargo.lock

@@ -652,19 +652,29 @@ pub async fn index(
         (Some(drv), None) => vec![drv],
         (None, Some(drvs)) => drvs,
         (None, None) => {
-            // Infer drive from output path
+            // No drives specified - index ALL available NTFS drives
             #[cfg(windows)]
-            let inferred = uffs_mft::infer_drive_from_path(&output);
+            {
+                if !uffs_mft::is_elevated() {
+                    anyhow::bail!(
+                        "Administrator privileges required.\n\n\
+                         UFFS reads the NTFS Master File Table directly, which requires elevated access.\n\n\
+                         Solutions:\n\
+                         1. Run PowerShell/Terminal as Administrator\n\
+                         2. Specify a drive explicitly: uffs index --drive C output.parquet"
+                    );
+                }
+                let all_drives = uffs_mft::detect_ntfs_drives();
+                if all_drives.is_empty() {
+                    anyhow::bail!("No NTFS drives found on this system");
+                }
+                info!(drives = ?all_drives, count = all_drives.len(), "No drive specified - indexing all NTFS drives");
+                all_drives
+            }
             #[cfg(not(windows))]
-            let inferred: Option<char> = None;
-
-            if let Some(drive) = inferred {
-                info!(drive = %drive, "Inferred drive from output path");
-                vec![drive]
-            } else {
+            {
                 anyhow::bail!(
-                    "Could not infer drive from path '{}'. Use --drive or --drives to specify.",
-                    output.display()
+                    "No drive specified. Use --drive or --drives to specify which drive(s) to index."
                 );
             }
         }

crates/uffs-cli/src/commands.rs

@@ -283,30 +283,27 @@ enum Commands {
         neg: String,
     },
 
-    /// Build an index from a drive's MFT
+    /// Build an index from drive MFT(s)
     ///
-    /// The drive to index is inferred from the output path:
-    ///   - `c:\tmp\index.parquet` → indexes drive C:
-    ///   - `index.parquet` → indexes the drive of the current directory
-    ///
-    /// Use --drive or --drives to override the inferred drive.
+    /// By default, indexes ALL available NTFS drives. Use --drive or --drives
+    /// to limit to specific drives.
     ///
     /// If no extension is provided, defaults to `.parquet`.
     ///
     /// Examples:
-    ///   uffs index index.parquet        # Index current drive
-    ///   uffs index c:\data\files.parquet # Index C: drive
-    ///   uffs index myindex              # Creates myindex.parquet
-    ///   uffs index -d D index.parquet   # Override: index D: drive
+    ///   uffs index index.parquet           # Index ALL drives
+    ///   uffs index -d C index.parquet      # Index only C: drive
+    ///   uffs index --drives C,D,E out.parquet  # Index C:, D:, E:
+    ///   uffs index myindex                 # Creates myindex.parquet
     Index {
         /// Output file path (extension defaults to .parquet)
         output: PathBuf,
 
-        /// Drive letter to index (overrides path inference)
+        /// Drive letter to index (limits to single drive)
         #[arg(short, long, conflicts_with = "drives", value_parser = parse_drive_letter)]
         drive: Option<char>,
 
-        /// Multiple drive letters to index concurrently (e.g., C,D,E)
+        /// Multiple drive letters to index (e.g., C,D,E)
         #[arg(long, value_delimiter = ',', conflicts_with = "drive", value_parser = parse_drive_letter)]
         drives: Option<Vec<char>>,
     },