Fix parsing of argument --positions-restore

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "audioserve"
-version = "0.28.12"
+version = "0.28.13"
 authors = ["Ivan <[email protected]>"]
 edition = "2021"
 rust-version = "1.72"

README.md

@@ -160,6 +160,8 @@ Proper functioning is (indeed) dependent on good connectivity - as position is s
 
 Position tracking is tightly connected with collection cache, so it'll not work for collection, which do not use caching (specified with `:no-cache` option). You can also backup positions to JSON file (highly recommended) for restoration in case of disk problems or for migration of audioserve - check `--positions-backup-file` and `--positions-backup-schedule` arguments of the program. Also if former argument is present you can force immediate backup by sending signal `sigusr2` to the program.
 
+To restore from positions backup run audioserve once with `--positions-restore=v1` and `--positions-backup-file` arguments and collections paths (ensure before that collections are scanned fully), it will finish immediately after restoring positions, then run it again with your usual arguments.
+
 Shared playback positions are behind default program feature `shared-positions`, so you can compile program without it.
 
 Shared positions also serve for marking finished / listened folders - if last file in the folder is listened till some offset from it's end (configurable via option `time-to-folder-end`, defaults to 10 seconds), folder if then marked as finished.  If you start listening the folder again it is unmarked - folder finished flag is derived directly of last listening position in this folder.

src/config/cli.rs

@@ -379,7 +379,7 @@ fn create_parser() -> Command {
         .arg(
             long_arg!(AUDIOSERVE_POSITIONS_RESTORE)
             .num_args(1)
-            .value_parser(["legacy", "v1"])
+            .value_parser(positions_restore_format)
             .requires(AUDIOSERVE_POSITIONS_BACKUP_FILE)
             .help("Restores positions from backup JSON file, value is version of file legacy is before audioserve v0.16,  v1 is current")
         )

src/config/validators.rs

@@ -6,6 +6,8 @@ use std::{
     time::Duration,
 };
 
+use super::PositionsBackupFormat;
+
 pub fn is_existing_dir(p: &str) -> Result<PathBuf, anyhow::Error> {
     let p = Path::new(p);
     if !p.is_dir() {
@@ -44,3 +46,9 @@ pub fn duration_secs(s: &str) -> Result<Duration, anyhow::Error> {
     let secs: u64 = s.parse().context("Invalid Duration")?;
     Ok(Duration::from_secs(secs))
 }
+
+pub fn positions_restore_format(s: &str) -> Result<PositionsBackupFormat, anyhow::Error> {
+    let format: PositionsBackupFormat =
+        s.parse().context(format!("Invalid format string {}", s))?;
+    Ok(format)
+}