From 2abf46c74761cbc77bbc4543df8465bd35add869 Mon Sep 17 00:00:00 2001
From: vcoppe <vianney.coppe@gmail.com>
Date: Sat, 3 Oct 2026 15:33:44 +0200
Subject: [PATCH] progress

---
 gpx-rs/engine/src/core/action/file.rs         |   1 +
 gpx-rs/engine/src/core/action/mod.rs          |   3 +
 gpx-rs/engine/src/core/gpx/common.rs          |   2 +-
 gpx-rs/engine/src/core/gpx/file.rs            |   6 +-
 gpx-rs/engine/src/core/gpx/segment.rs         |   4 +-
 gpx-rs/engine/src/core/gpx/track.rs           |   6 +-
 gpx-rs/engine/src/core/mod.rs                 |   2 +
 gpx-rs/engine/src/engine/command/applier.rs   |  26 ++++
 gpx-rs/engine/src/engine/command/mod.rs       |   4 +
 gpx-rs/engine/src/engine/command/pattern.rs   |  38 ++++++
 gpx-rs/engine/src/engine/engine.rs            | 123 ++++++++----------
 gpx-rs/engine/src/engine/mod.rs               |   2 -
 gpx-rs/engine/src/engine/state/mod.rs         |  10 ++
 gpx-rs/engine/src/engine/state/order.rs       |   4 +
 .../src/engine/{ => state}/selection.rs       |   8 --
 gpx-rs/engine/src/engine/state/stack.rs       |   6 +-
 16 files changed, 151 insertions(+), 94 deletions(-)
 create mode 100644 gpx-rs/engine/src/core/action/file.rs
 create mode 100644 gpx-rs/engine/src/core/action/mod.rs
 create mode 100644 gpx-rs/engine/src/engine/command/applier.rs
 create mode 100644 gpx-rs/engine/src/engine/command/pattern.rs
 create mode 100644 gpx-rs/engine/src/engine/state/order.rs
 rename gpx-rs/engine/src/engine/{ => state}/selection.rs (74%)

diff --git a/gpx-rs/engine/src/core/action/file.rs b/gpx-rs/engine/src/core/action/file.rs
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/gpx-rs/engine/src/core/action/file.rs
@@ -0,0 +1 @@
+
diff --git a/gpx-rs/engine/src/core/action/mod.rs b/gpx-rs/engine/src/core/action/mod.rs
new file mode 100644
index 000000000..529c201fa
--- /dev/null
+++ b/gpx-rs/engine/src/core/action/mod.rs
@@ -0,0 +1,3 @@
+mod file;
+
+pub use file::*;
diff --git a/gpx-rs/engine/src/core/gpx/common.rs b/gpx-rs/engine/src/core/gpx/common.rs
index 29897a73f..1fd1f3501 100644
--- a/gpx-rs/engine/src/core/gpx/common.rs
+++ b/gpx-rs/engine/src/core/gpx/common.rs
@@ -1,4 +1,4 @@
-#[derive(Debug, Default, PartialEq, Eq)]
+#[derive(Debug, Default, Clone, PartialEq, Eq)]
 pub struct Link {
     pub href: String,
     pub text: Option<String>,
diff --git a/gpx-rs/engine/src/core/gpx/file.rs b/gpx-rs/engine/src/core/gpx/file.rs
index 1a035bb06..0e7d8b0a0 100644
--- a/gpx-rs/engine/src/core/gpx/file.rs
+++ b/gpx-rs/engine/src/core/gpx/file.rs
@@ -13,7 +13,7 @@ impl Default for FileId {
     }
 }
 
-#[derive(Debug, Default, PartialEq)]
+#[derive(Debug, Default, Clone, PartialEq)]
 pub struct File {
     pub id: FileId,
     pub info: FileInfo,
@@ -22,7 +22,7 @@ pub struct File {
     // TODO routes
 }
 
-#[derive(Debug, Default, PartialEq)]
+#[derive(Debug, Default, Clone, PartialEq)]
 pub struct FileInfo {
     pub name: String,
     pub desc: Option<String>,
@@ -31,7 +31,7 @@ pub struct FileInfo {
     pub time: Option<i64>,
 }
 
-#[derive(Debug, Default, PartialEq)]
+#[derive(Debug, Default, Clone, PartialEq)]
 pub struct Author {
     pub name: Option<String>,
     pub email: Option<String>,
diff --git a/gpx-rs/engine/src/core/gpx/segment.rs b/gpx-rs/engine/src/core/gpx/segment.rs
index de5d68989..f32468a94 100644
--- a/gpx-rs/engine/src/core/gpx/segment.rs
+++ b/gpx-rs/engine/src/core/gpx/segment.rs
@@ -4,7 +4,7 @@ use uuid::Uuid;
 
 use crate::{Trackpoint, TrackpointChunk};
 
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct TrackSegmentId(Uuid);
 
 impl Default for TrackSegmentId {
@@ -22,7 +22,7 @@ impl Default for TrackSegmentRevisionId {
     }
 }
 
-#[derive(Debug, Default, PartialEq)]
+#[derive(Debug, Default, Clone, PartialEq)]
 pub struct TrackSegment {
     pub id: TrackSegmentId,
     pub rev_id: TrackSegmentRevisionId,
diff --git a/gpx-rs/engine/src/core/gpx/track.rs b/gpx-rs/engine/src/core/gpx/track.rs
index 2b015ce4d..41cd4c381 100644
--- a/gpx-rs/engine/src/core/gpx/track.rs
+++ b/gpx-rs/engine/src/core/gpx/track.rs
@@ -2,7 +2,7 @@ use uuid::Uuid;
 
 use crate::{Link, TrackSegment};
 
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct TrackId(Uuid);
 
 impl Default for TrackId {
@@ -11,14 +11,14 @@ impl Default for TrackId {
     }
 }
 
-#[derive(Debug, Default, PartialEq)]
+#[derive(Debug, Default, Clone, PartialEq)]
 pub struct Track {
     pub id: TrackId,
     pub info: TrackInfo,
     pub trkseg: Vec<TrackSegment>,
 }
 
-#[derive(Debug, Default, PartialEq)]
+#[derive(Debug, Default, Clone, PartialEq)]
 pub struct TrackInfo {
     pub name: Option<String>,
     pub cmt: Option<String>,
diff --git a/gpx-rs/engine/src/core/mod.rs b/gpx-rs/engine/src/core/mod.rs
index 1e058e91f..b03150b56 100644
--- a/gpx-rs/engine/src/core/mod.rs
+++ b/gpx-rs/engine/src/core/mod.rs
@@ -1,9 +1,11 @@
+mod action;
 mod algorithm;
 pub(crate) mod gpx;
 mod io;
 pub(crate) mod statistics;
 mod utils;
 
+pub use action::*;
 pub use algorithm::*;
 pub use gpx::*;
 pub use io::*;
diff --git a/gpx-rs/engine/src/engine/command/applier.rs b/gpx-rs/engine/src/engine/command/applier.rs
new file mode 100644
index 000000000..bf3c4c214
--- /dev/null
+++ b/gpx-rs/engine/src/engine/command/applier.rs
@@ -0,0 +1,26 @@
+use crate::{File, State, parse, produce, update_each_selected_file};
+
+pub fn create_file(state: &mut State, name: &str) -> Result<(), String> {
+    produce(state, |_| {
+        let mut file = File::default();
+        file.info.name = name.to_owned();
+        vec![file]
+    });
+    Ok(())
+}
+
+pub fn load_file(state: &mut State, data: &[u8]) -> Result<(), String> {
+    let file = parse(data).map_err(|err| err.to_string())?;
+    produce(state, |_| vec![file]);
+    Ok(())
+}
+
+pub fn update_metadata(state: &mut State, name: &str, desc: &str) -> Result<(), String> {
+    update_each_selected_file(state, &mut |file| {
+        let mut next = (*file).clone();
+        next.info.name = name.to_owned();
+        next.info.desc = Some(desc.to_owned());
+        next
+    });
+    Ok(())
+}
diff --git a/gpx-rs/engine/src/engine/command/mod.rs b/gpx-rs/engine/src/engine/command/mod.rs
index a30f72292..525bd6863 100644
--- a/gpx-rs/engine/src/engine/command/mod.rs
+++ b/gpx-rs/engine/src/engine/command/mod.rs
@@ -1,3 +1,7 @@
+mod applier;
 mod command;
+mod pattern;
 
+pub use applier::*;
 pub use command::*;
+pub use pattern::*;
diff --git a/gpx-rs/engine/src/engine/command/pattern.rs b/gpx-rs/engine/src/engine/command/pattern.rs
new file mode 100644
index 000000000..f01854fe9
--- /dev/null
+++ b/gpx-rs/engine/src/engine/command/pattern.rs
@@ -0,0 +1,38 @@
+use std::{
+    collections::{HashSet, hash_map::Entry},
+    rc::Rc,
+};
+
+use crate::{File, FileId, Selection, State};
+
+pub fn produce<F>(state: &mut State, f: F)
+where
+    F: FnOnce(&State) -> Vec<File>,
+{
+    *state.selection = Selection::Empty;
+    for file in f(state).drain(..) {
+        let file_id = file.id;
+        state.files.insert(file_id, Rc::new(file));
+        state.order.0.push(file_id);
+        if matches!(*state.selection, Selection::Empty) {
+            let mut file_ids: HashSet<FileId> = Default::default();
+            file_ids.insert(file_id);
+            *state.selection = Selection::File { file_ids };
+        }
+    }
+}
+
+pub fn update_each_selected_file<F>(state: &mut State, f: &mut F)
+where
+    F: FnMut(&File) -> File,
+{
+    if let Selection::File { file_ids } = state.selection {
+        for file_id in file_ids.iter() {
+            if let Entry::Occupied(mut e) = state.files.entry(*file_id) {
+                let file = e.get();
+                let updated = Rc::new(f(file.as_ref()));
+                e.insert(updated);
+            }
+        }
+    }
+}
diff --git a/gpx-rs/engine/src/engine/engine.rs b/gpx-rs/engine/src/engine/engine.rs
index 1faac4f65..bafe405fc 100644
--- a/gpx-rs/engine/src/engine/engine.rs
+++ b/gpx-rs/engine/src/engine/engine.rs
@@ -1,17 +1,15 @@
 // TODO license in every file
 
-use std::rc::Rc;
-
-use uuid::Uuid;
-
 use crate::{
-    Command, File, FileId, Selection, Stack, StackEntry, StatisticsBuffer, StatisticsCache, parse,
+    Command, FileOrder, Selection, Stack, State, StatisticsBuffer, StatisticsCache, create_file,
+    load_file, update_metadata,
 };
 
 #[derive(Debug, Default)]
 pub struct Engine {
     stack: Stack,
     selection: Selection,
+    order: FileOrder,
     statistics_cache: StatisticsCache,
     statistics_buffer: StatisticsBuffer,
 }
@@ -21,75 +19,54 @@ impl Engine {
         &self.statistics_buffer
     }
 
-    pub fn create_file(&mut self, name: &str) -> bool {
-        self.event_loop(|entry| {
-            let mut file = File::default();
-            file.info.name = name.to_string();
-            entry.insert(file.id, Rc::new(file));
-            true
-        })
-    }
-
-    pub fn load_file(&mut self, data: &[u8]) -> bool {
-        self.event_loop(|entry| {
-            if let Ok(file) = parse(data) {
-                entry.insert(file.id, Rc::new(file));
-                true
-            } else {
-                false
-            }
-        })
-    }
-
-    pub fn delete_file(&mut self, id: &[u8]) -> bool {
-        self.event_loop(|entry| {
-            if let Ok(id) = Uuid::from_slice(id) {
-                let id = FileId(id);
-                entry.remove(&id).is_some()
-            } else {
-                false
-            }
-        })
-    }
+    // pub fn delete_file(&mut self, id: &[u8]) -> bool {
+    //     self.event_loop(|entry| {
+    //         if let Ok(id) = Uuid::from_slice(id) {
+    //             let id = FileId(id);
+    //             entry.remove(&id).is_some()
+    //         } else {
+    //             false
+    //         }
+    //     })
+    // }
 
     /// Single entry point for every user action coming from the frontend.
     pub fn execute(&mut self, command: Command) -> bool {
-        match command {
-            Command::New { name } => self.create_file(name),
-            Command::Load { data } => self.load_file(data),
-            Command::Delete
-            | Command::DeleteAll
-            | Command::Duplicate
-            | Command::Metadata { .. }
-            | Command::Style { .. }
-            | Command::NewTrack
-            | Command::NewTrackSegment
-            | Command::Reverse
-            | Command::Append { .. }
-            | Command::Replace { .. }
-            | Command::NewWaypoint { .. }
-            | Command::MoveWaypoint { .. }
-            | Command::Crop { .. }
-            | Command::Split { .. }
-            | Command::Time
-            | Command::Merge { .. }
-            | Command::Extract
-            | Command::Elevation { .. }
-            | Command::Clean { .. }
-            | Command::Undo
-            | Command::Redo
-            | Command::Select { .. }
-            | Command::AddSelect { .. }
-            | Command::SelectAll => todo!("command not implemented yet"),
-        }
-    }
-
-    fn event_loop<F>(&mut self, f: F) -> bool
-    where
-        F: FnOnce(&mut StackEntry) -> bool,
-    {
-        if let Some(diff) = self.stack.create_and_push_next(f) {
-            self.selection.select(diff.added[0]);
+        if let Some(diff) = self.stack.create_and_push_next(|files| {
+            let mut state = State {
+                files,
+                selection: &mut self.selection,
+                order: &mut self.order,
+            };
+            match command {
+                Command::New { name } => create_file(&mut state, name),
+                Command::Load { data } => load_file(&mut state, data),
+                Command::Metadata { name, desc } => update_metadata(&mut state, name, desc),
+                Command::Delete
+                | Command::DeleteAll
+                | Command::Duplicate
+                | Command::Style { .. }
+                | Command::NewTrack
+                | Command::NewTrackSegment
+                | Command::Reverse
+                | Command::Append { .. }
+                | Command::Replace { .. }
+                | Command::NewWaypoint { .. }
+                | Command::MoveWaypoint { .. }
+                | Command::Crop { .. }
+                | Command::Split { .. }
+                | Command::Time
+                | Command::Merge { .. }
+                | Command::Extract
+                | Command::Elevation { .. }
+                | Command::Clean { .. }
+                | Command::Undo
+                | Command::Redo
+                | Command::Select { .. }
+                | Command::AddSelect { .. }
+                | Command::SelectAll => todo!("command not implemented yet"),
+            }
+        }) {
             self.statistics_cache.update(self.stack.current());
             self.statistics_buffer.update(
                 &self
@@ -117,7 +94,9 @@ mod tests {
         let mut data = String::new();
         let _ = f.read_to_string(&mut data);
 
-        engine.load_file(data.as_bytes());
+        engine.execute(Command::Load {
+            data: data.as_bytes(),
+        });
 
         assert_eq!(engine.statistics_buffer.total_distance.len(), 80);
     }
diff --git a/gpx-rs/engine/src/engine/mod.rs b/gpx-rs/engine/src/engine/mod.rs
index b58143013..9c5c7eedd 100644
--- a/gpx-rs/engine/src/engine/mod.rs
+++ b/gpx-rs/engine/src/engine/mod.rs
@@ -1,11 +1,9 @@
 mod command;
 mod derived;
 mod engine;
-mod selection;
 mod state;
 
 pub use command::*;
 pub use derived::*;
 pub use engine::*;
-pub use selection::*;
 pub use state::*;
diff --git a/gpx-rs/engine/src/engine/state/mod.rs b/gpx-rs/engine/src/engine/state/mod.rs
index b21354ddf..2b91600fb 100644
--- a/gpx-rs/engine/src/engine/state/mod.rs
+++ b/gpx-rs/engine/src/engine/state/mod.rs
@@ -1,3 +1,13 @@
+mod order;
+mod selection;
 mod stack;
 
+pub use order::*;
+pub use selection::*;
 pub use stack::*;
+
+pub struct State<'a> {
+    pub files: &'a mut StackEntry,
+    pub selection: &'a mut Selection,
+    pub order: &'a mut FileOrder,
+}
diff --git a/gpx-rs/engine/src/engine/state/order.rs b/gpx-rs/engine/src/engine/state/order.rs
new file mode 100644
index 000000000..5c63c027e
--- /dev/null
+++ b/gpx-rs/engine/src/engine/state/order.rs
@@ -0,0 +1,4 @@
+use crate::FileId;
+
+#[derive(Debug, Default)]
+pub struct FileOrder(pub Vec<FileId>);
diff --git a/gpx-rs/engine/src/engine/selection.rs b/gpx-rs/engine/src/engine/state/selection.rs
similarity index 74%
rename from gpx-rs/engine/src/engine/selection.rs
rename to gpx-rs/engine/src/engine/state/selection.rs
index 2f4d6a42e..3cf7dee79 100644
--- a/gpx-rs/engine/src/engine/selection.rs
+++ b/gpx-rs/engine/src/engine/state/selection.rs
@@ -26,11 +26,3 @@ pub enum Selection {
         wpt_ids: HashSet<WaypointId>,
     },
 }
-
-impl Selection {
-    pub fn select(&mut self, id: FileId) {
-        let mut file_ids = HashSet::default();
-        file_ids.insert(id);
-        *self = Selection::File { file_ids };
-    }
-}
diff --git a/gpx-rs/engine/src/engine/state/stack.rs b/gpx-rs/engine/src/engine/state/stack.rs
index b9db13534..0201d6443 100644
--- a/gpx-rs/engine/src/engine/state/stack.rs
+++ b/gpx-rs/engine/src/engine/state/stack.rs
@@ -18,11 +18,11 @@ impl Stack {
 
     pub fn create_and_push_next<F>(&mut self, f: F) -> Option<Diff>
     where
-        F: FnOnce(&mut StackEntry) -> bool,
+        F: FnOnce(&mut StackEntry) -> Result<(), String>,
     {
         self.record_diff(|stack| {
             let mut next = stack.current().map_or_default(|c| c.clone());
-            if f(&mut next) {
+            if f(&mut next).is_ok() {
                 stack.push(next);
             }
         })
@@ -139,7 +139,7 @@ mod tests {
         let diff = stack.create_and_push_next(|e| {
             let file = Rc::new(File::default());
             e.insert(file.id, file);
-            true
+            Ok(())
         });
 
         assert!(stack.can_undo());