progress

gpx-rs/src/api/dto.rs

@@ -68,6 +68,11 @@ impl Outcome {
         Self::new(&engine::Outcome::default(), None)
     }
 
+    /// The ids of the files that the call added.
+    pub fn added(&self) -> &[String] {
+        &self.added
+    }
+
     /// Whether the call did nothing and says why.
     pub fn has_error(&self) -> bool {
         self.error.is_some()

tauri/src/commands/disk.rs

@@ -1,16 +1,21 @@
-//! The files of the engine and the file system: picking files and folders, saving, and what the
-//! frontend shows of it (see `workspace`).
+//! The files of the engine and the file system: picking files and folders, saving, closing, and
+//! what the frontend shows of it (see `workspace`).
+//!
+//! The commands that can lose the edits of a file (closing, opening another folder) take what to do
+//! with the files that have some: the frontend asks the user, and the files that have edits stay
+//! open if it does not say.
 
 use std::collections::BTreeMap;
 use std::path::PathBuf;
 
-use gpx_engine::api;
+use gpx_engine::{ExportOptions, api};
+use serde::Deserialize;
 use tauri::{AppHandle, Runtime, State};
 use tauri_plugin_dialog::{DialogExt, FilePath};
 use uuid::Uuid;
 
 use crate::state::AppState;
-use crate::workspace::{Unsaved, WorkspaceState};
+use crate::workspace::{Entry, Unsaved, WorkspaceState, free_path};
 
 fn paths(picked: Vec<FilePath>) -> Vec<PathBuf> {
     picked
@@ -35,17 +40,186 @@ pub fn open_files<R: Runtime>(app: AppHandle<R>, state: State<AppState>) -> api:
     let Some(picked) = picked else {
         return api::Outcome::failed_none();
     };
-    let files = paths(picked);
+    open_paths(state, paths(picked))
+}
+
+/// Opens files that are on the disk, like the ones of the tree of the open folder. They get selected.
+#[tauri::command(async)]
+pub fn open_paths(state: State<AppState>, paths: Vec<PathBuf>) -> api::Outcome {
     state.core(move |core| {
-        let outcome = core.workspace.open_files(&mut core.engine, &files, true);
+        let outcome = core.workspace.open_files(&mut core.engine, &paths, true);
         core.keep_workspace();
         core.persist();
         outcome
     })
 }
 
-/// Opens the folder that the user picks: its GPX files are opened and it is watched. The folder
-/// that was open is closed, `unsaved` says what to do with its files that have unsaved edits.
+/// Writes the files among `ids` that are not the ones on the disk, asking where to put the ones
+/// that have no place: the file dialog for a single one, a folder for several of them. Says whether
+/// they were written, which is not the case if the user cancelled.
+///
+/// The files whose file on the disk was replaced are overwritten: the frontend asks before.
+fn write_unsaved<R: Runtime>(
+    app: &AppHandle<R>,
+    state: &AppState,
+    ids: Vec<Uuid>,
+) -> Result<bool, String> {
+    let (unlinked, start) = {
+        let ids = ids.clone();
+        state.core(move |core| {
+            (
+                core.workspace.unlinked(&core.engine, &ids),
+                core.workspace.folder.clone(),
+            )
+        })
+    };
+    let mut chosen = BTreeMap::new();
+    let mut folder = None;
+    match unlinked.as_slice() {
+        [] => {}
+        [(id, name)] => {
+            let mut dialog = app
+                .dialog()
+                .file()
+                .add_filter("GPX", &["gpx"])
+                .set_file_name(format!("{name}.gpx"));
+            if let Some(start) = &start {
+                dialog = dialog.set_directory(start);
+            }
+            match dialog
+                .blocking_save_file()
+                .and_then(|path| path.into_path().ok())
+            {
+                Some(path) => {
+                    chosen.insert(*id, path);
+                }
+                None => return Ok(false),
+            }
+        }
+        _ => {
+            let mut dialog = app.dialog().file();
+            if let Some(start) = &start {
+                dialog = dialog.set_directory(start);
+            }
+            match dialog
+                .blocking_pick_folder()
+                .and_then(|path| path.into_path().ok())
+            {
+                Some(path) => folder = Some(path),
+                None => return Ok(false),
+            }
+        }
+    }
+    state.core(move |core| {
+        let result = core
+            .workspace
+            .save(&core.engine, &ids, &chosen, folder.as_deref());
+        core.keep_workspace();
+        core.announce(None);
+        result.map(|()| true)
+    })
+}
+
+/// Writes files to the disk, replacing what is there. The ones that are not on the disk yet go in
+/// their folder, or where the user says. Says whether they were written (`false` if the user
+/// cancelled).
+#[tauri::command(async)]
+pub fn save_files<R: Runtime>(
+    app: AppHandle<R>,
+    state: State<AppState>,
+    file_ids: Vec<Uuid>,
+) -> Result<bool, String> {
+    write_unsaved(&app, &state, file_ids)
+}
+
+/// Writes a file where the user says, which is where the file is from then on. Says whether it was
+/// written (`false` if the user cancelled).
+#[tauri::command(async)]
+pub fn save_file_as<R: Runtime>(
+    app: AppHandle<R>,
+    state: State<AppState>,
+    file_id: Uuid,
+) -> Result<bool, String> {
+    let (name, current, folder) = state.core(move |core| {
+        let name = core
+            .engine
+            .file_structure(&gpx_engine::FileId(file_id))
+            .map(|structure| structure.name.clone());
+        let status = core.workspace_state();
+        let file = status.files.get(&file_id.to_string());
+        let current = file.and_then(|file| file.path.clone().map(PathBuf::from));
+        let folder = file
+            .and_then(|file| file.folder.clone().map(PathBuf::from))
+            .or(status.folder.map(PathBuf::from));
+        (name, current, folder)
+    });
+    let Some(name) = name else {
+        return Ok(false);
+    };
+    let mut dialog = app.dialog().file().add_filter("GPX", &["gpx"]);
+    match &current {
+        Some(path) => {
+            if let Some(file_name) = path.file_name() {
+                dialog = dialog.set_file_name(file_name.to_string_lossy());
+            }
+            if let Some(parent) = path.parent() {
+                dialog = dialog.set_directory(parent);
+            }
+        }
+        None => {
+            dialog = dialog.set_file_name(format!("{name}.gpx"));
+            if let Some(folder) = &folder {
+                dialog = dialog.set_directory(folder);
+            }
+        }
+    }
+    let Some(path) = dialog
+        .blocking_save_file()
+        .and_then(|path| path.into_path().ok())
+    else {
+        return Ok(false);
+    };
+    state.core(move |core| {
+        let result = core.workspace.save_as(&core.engine, file_id, &path);
+        core.keep_workspace();
+        core.announce(None);
+        result.map(|()| true)
+    })
+}
+
+/// Reads files again from the disk: the edits they have are lost (they are one undo step).
+#[tauri::command(async)]
+pub fn reload_files(state: State<AppState>, file_ids: Vec<Uuid>) -> Result<api::Outcome, String> {
+    state.core(move |core| {
+        let outcome = core.workspace.reload(&mut core.engine, &file_ids);
+        core.keep_workspace();
+        core.persist();
+        core.announce(None);
+        outcome
+    })
+}
+
+/// The files among `ids` that are not the ones on the disk, saved first if `unsaved` says so.
+/// Says whether to go on, which is not the case if the user cancelled saving them.
+fn settle<R: Runtime>(
+    app: &AppHandle<R>,
+    state: &AppState,
+    ids: Vec<Uuid>,
+    unsaved: Option<Unsaved>,
+) -> Result<bool, String> {
+    if unsaved != Some(Unsaved::Save) {
+        return Ok(true);
+    }
+    let unsaved_ids = state.core(move |core| core.workspace.unsaved(&core.engine, &ids));
+    if unsaved_ids.is_empty() {
+        return Ok(true);
+    }
+    write_unsaved(app, state, unsaved_ids)
+}
+
+/// Opens the folder that the user picks, which is watched. Its files are not opened. The folder
+/// that was open is closed with its files: `unsaved` says what to do with the ones that have
+/// unsaved edits.
 #[tauri::command(async)]
 pub fn open_folder<R: Runtime>(
     app: AppHandle<R>,
@@ -60,80 +234,167 @@ pub fn open_folder<R: Runtime>(
     else {
         return Ok(api::Outcome::failed_none());
     };
+    let all = state.core(|core| core.workspace.all(&core.engine));
+    if !settle(&app, &state, all, unsaved)? {
+        return Ok(api::Outcome::failed_none());
+    }
     state.core(move |core| {
+        let discard = unsaved.is_some();
         let outcome = core
             .workspace
-            .open_folder(&mut core.engine, &folder, unsaved);
+            .open_folder(&mut core.engine, &folder, discard);
         core.keep_workspace();
         core.persist();
         core.watch();
         core.announce(None);
-        outcome
+        Ok(outcome)
     })
 }
 
-/// Closes the folder: it is not watched anymore, and its files are closed. `unsaved` says what to
-/// do with the ones that have unsaved edits (they stay without it).
+/// Closes the folder: it is not watched anymore, and the files are closed with it. `unsaved` says
+/// what to do with the ones that have unsaved edits (they stay open without it).
 #[tauri::command(async)]
-pub fn close_folder(
+pub fn close_folder<R: Runtime>(
+    app: AppHandle<R>,
     state: State<AppState>,
     unsaved: Option<Unsaved>,
 ) -> Result<api::Outcome, String> {
+    let all = state.core(|core| core.workspace.all(&core.engine));
+    if !settle(&app, &state, all, unsaved)? {
+        return Ok(api::Outcome::failed_none());
+    }
     state.core(move |core| {
-        let outcome = core.workspace.close_folder(&mut core.engine, unsaved);
+        let outcome = core
+            .workspace
+            .close_folder(&mut core.engine, unsaved.is_some());
         core.keep_workspace();
         core.persist();
         core.watch();
         core.announce(None);
-        outcome
+        Ok(outcome)
     })
 }
 
-/// Writes files to the disk, replacing what is there. The ones that are not on the disk yet go in
-/// the open folder, or where the user says if there is none.
+/// Closes files. `unsaved` says what to do with the ones that have unsaved edits: they are saved
+/// first, or the edits are lost (they stay open without it).
 #[tauri::command(async)]
-pub fn save_files<R: Runtime>(
+pub fn close_files<R: Runtime>(
     app: AppHandle<R>,
     state: State<AppState>,
     file_ids: Vec<Uuid>,
-) -> Result<(), String> {
-    let (ids, unlinked, folder) = {
-        let ids = file_ids.clone();
-        state.core(move |core| {
-            (
-                ids.clone(),
-                core.workspace.unlinked(&core.engine, &ids),
-                core.workspace.folder.clone(),
-            )
-        })
-    };
-    let mut chosen = BTreeMap::new();
-    // with a folder open, a new file goes in it: nobody is asked
-    let to_ask = if folder.is_some() { vec![] } else { unlinked };
-    for (id, name) in to_ask {
-        let mut dialog = app
-            .dialog()
-            .file()
-            .add_filter("GPX", &["gpx"])
-            .set_file_name(format!("{name}.gpx"));
-        if let Some(folder) = &folder {
-            dialog = dialog.set_directory(folder);
-        }
-        match dialog
-            .blocking_save_file()
-            .and_then(|path| path.into_path().ok())
-        {
-            Some(path) => {
-                chosen.insert(id, path);
-            }
-            // cancelled: the others are not saved either
-            None => return Ok(()),
-        }
+    unsaved: Option<Unsaved>,
+) -> Result<api::Outcome, String> {
+    if !settle(&app, &state, file_ids.clone(), unsaved)? {
+        return Ok(api::Outcome::failed_none());
     }
     state.core(move |core| {
-        let result = core.workspace.save(&core.engine, &ids, &chosen);
+        let outcome = core
+            .workspace
+            .close_files(&mut core.engine, &file_ids, unsaved.is_some());
         core.keep_workspace();
+        core.persist();
         core.announce(None);
-        result
+        Ok(outcome)
     })
 }
+
+/// The folders and GPX files that are in a folder of the open folder, or in it (the root of the
+/// tree when no path is given).
+#[tauri::command(async)]
+pub fn list_folder(state: State<AppState>, path: Option<PathBuf>) -> Result<Vec<Entry>, String> {
+    state.core(move |core| {
+        let Some(path) = path.or_else(|| core.workspace.folder.clone()) else {
+            return Ok(vec![]);
+        };
+        core.workspace.list_folder(&path)
+    })
+}
+
+/// What the files are exported with, see `ExportOptions`.
+#[derive(Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ExportArguments {
+    time: bool,
+    hr: bool,
+    cad: bool,
+    atemp: bool,
+    power: bool,
+    osm: bool,
+    as_route: bool,
+}
+
+impl From<ExportArguments> for ExportOptions {
+    fn from(arguments: ExportArguments) -> Self {
+        Self {
+            time: arguments.time,
+            hr: arguments.hr,
+            cad: arguments.cad,
+            atemp: arguments.atemp,
+            power: arguments.power,
+            osm: arguments.osm,
+            as_route: arguments.as_route,
+        }
+    }
+}
+
+/// Writes copies of files where the user says: a file dialog for a single one, a folder for
+/// several. The files stay as they are. Says whether they were written (`false` if the user
+/// cancelled).
+#[tauri::command(async)]
+pub fn export_files<R: Runtime>(
+    app: AppHandle<R>,
+    state: State<AppState>,
+    file_ids: Vec<Uuid>,
+    options: ExportArguments,
+) -> Result<bool, String> {
+    let options = ExportOptions::from(options);
+    let files: Vec<(String, Vec<u8>)> = state.read(move |engine| {
+        file_ids
+            .iter()
+            .filter_map(|id| {
+                let name = engine
+                    .file_structure(&gpx_engine::FileId(*id))?
+                    .name
+                    .clone();
+                Some((name, api::export_file(engine, *id, options)?))
+            })
+            .collect()
+    });
+    let write = |path: PathBuf, bytes: &[u8]| {
+        crate::store::write_atomically(&path, bytes)
+            .map_err(|error| format!("{}: {error}", path.display()))
+    };
+    match files.as_slice() {
+        [] => Ok(false),
+        [(name, bytes)] => {
+            let Some(path) = app
+                .dialog()
+                .file()
+                .add_filter("GPX", &["gpx"])
+                .set_file_name(format!("{name}.gpx"))
+                .blocking_save_file()
+                .and_then(|path| path.into_path().ok())
+            else {
+                return Ok(false);
+            };
+            write(path, bytes).map(|()| true)
+        }
+        _ => {
+            let Some(folder) = app
+                .dialog()
+                .file()
+                .blocking_pick_folder()
+                .and_then(|path| path.into_path().ok())
+            else {
+                return Ok(false);
+            };
+            let mut written: Vec<PathBuf> = vec![];
+            for (name, bytes) in &files {
+                let path = free_path(&folder, name, |path| written.iter().any(|w| w == path));
+                write(path.clone(), bytes)?;
+                written.push(path);
+            }
+            Ok(true)
+        }
+    }
+}

tauri/src/commands/edit.rs

@@ -139,12 +139,12 @@ pub fn create_artificial_timestamps(
 
 #[tauri::command(async)]
 pub fn merge(state: State<AppState>, merge_type: MergeType, remove_gaps: bool) -> api::Outcome {
-    state.run(move |e| api::merge(e, merge_type, remove_gaps))
+    state.core(move |core| core.creating(None, false, |e| api::merge(e, merge_type, remove_gaps)))
 }
 
 #[tauri::command(async)]
 pub fn extract(state: State<AppState>) -> api::Outcome {
-    state.run(api::extract)
+    state.core(|core| core.creating(None, false, api::extract))
 }
 
 #[tauri::command(async)]
@@ -214,5 +214,5 @@ pub fn split(
     at: u32,
     split_type: SplitType,
 ) -> api::Outcome {
-    state.run(move |e| api::split(e, revision, at, split_type))
+    state.core(move |core| core.creating(None, false, |e| api::split(e, revision, at, split_type)))
 }

tauri/src/commands/files.rs

@@ -1,5 +1,7 @@
 //! Creating, loading, deleting, moving, copying and pasting files and their elements, and undoing.
 
+use std::path::PathBuf;
+
 use gpx_engine::api;
 use tauri::State;
 use tauri::ipc::{InvokeBody, Request};
@@ -14,8 +16,10 @@ pub fn new_file(
     lng: Option<f64>,
     lat: Option<f64>,
     ele: Option<f64>,
+    folder: Option<PathBuf>,
 ) -> api::Outcome {
-    state.run(move |e| api::new_file(e, &name, lng, lat, ele))
+    // in `folder` if it is given, otherwise like the selected file, otherwise in the open folder
+    state.core(move |core| core.creating(folder, true, |e| api::new_file(e, &name, lng, lat, ele)))
 }
 
 /// The files are in the body, one after the other, the headers `lengths` and `names` (JSON,
@@ -61,7 +65,7 @@ fn percent_decode(value: &str) -> Option<String> {
 
 #[tauri::command(async)]
 pub fn duplicate(state: State<AppState>) -> api::Outcome {
-    state.run(api::duplicate)
+    state.core(|core| core.creating(None, false, api::duplicate))
 }
 
 #[tauri::command(async)]

tauri/src/lib.rs

@@ -184,9 +184,15 @@ fn register_commands<R: tauri::Runtime>(builder: tauri::Builder<R>) -> tauri::Bu
         // the file system
         disk::workspace_state,
         disk::open_files,
+        disk::open_paths,
         disk::open_folder,
         disk::close_folder,
+        disk::close_files,
         disk::save_files,
+        disk::save_file_as,
+        disk::reload_files,
+        disk::export_files,
+        disk::list_folder,
     ])
 }
 

tauri/src/state.rs

@@ -5,7 +5,7 @@
 //! watcher of the open folder), and the commands send that thread jobs: they are done one after the
 //! other, in the order they were sent.
 
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 use std::sync::mpsc::{self, Sender};
 use std::sync::{Arc, Mutex};
 use std::thread;
@@ -32,6 +32,8 @@ pub struct Core {
     storage: Arc<FileStorage>,
     persister: Persister,
     watcher: Option<Debouncer<notify::RecommendedWatcher>>,
+    /// What the watcher watches, see `Workspace::watched`.
+    watching: Vec<(PathBuf, bool)>,
     jobs: Sender<Job>,
     emit: Emit,
 }
@@ -50,6 +52,7 @@ impl Core {
             persister: Persister::default(),
             storage,
             watcher: None,
+            watching: vec![],
             jobs,
             emit,
         };
@@ -93,8 +96,10 @@ impl Core {
         self.announce(None);
     }
 
-    pub fn keep_workspace(&self) {
+    /// Writes the workspace, and watches what it holds (a file may have been opened or closed).
+    pub fn keep_workspace(&mut self) {
         self.workspace.write(self.storage.root());
+        self.watch();
     }
 
     pub fn workspace_state(&self) -> WorkspaceState {
@@ -109,13 +114,16 @@ impl Core {
         (self.emit)("workspace-changed", to_json(&self.workspace_state()));
     }
 
-    /// Watches the open folder (and only it).
+    /// Watches the open folder, and the folders of the files that are linked outside of it. Does
+    /// nothing if that is what is watched already.
     pub fn watch(&mut self) {
-        self.watcher = None;
-        let Some(folder) = self.workspace.folder.clone() else {
+        let wanted = self.workspace.watched();
+        if wanted == self.watching && (self.watcher.is_some() || wanted.is_empty()) {
             return;
-        };
-        if !Path::new(&folder).is_dir() {
+        }
+        self.watcher = None;
+        self.watching = wanted.clone();
+        if wanted.is_empty() {
             return;
         }
         let jobs = self.jobs.clone();
@@ -131,23 +139,76 @@ impl Core {
         );
         match debouncer {
             Ok(mut debouncer) => {
-                match debouncer.watcher().watch(&folder, RecursiveMode::Recursive) {
-                    Ok(()) => self.watcher = Some(debouncer),
-                    Err(error) => eprintln!("the folder cannot be watched: {error}"),
+                for (path, recursive) in &wanted {
+                    let mode = if *recursive {
+                        RecursiveMode::Recursive
+                    } else {
+                        RecursiveMode::NonRecursive
+                    };
+                    if let Err(error) = debouncer.watcher().watch(path, mode) {
+                        eprintln!("{} cannot be watched: {error}", path.display());
+                    }
                 }
+                self.watcher = Some(debouncer);
             }
-            Err(error) => eprintln!("the folder cannot be watched: {error}"),
+            Err(error) => eprintln!("the files cannot be watched: {error}"),
         }
     }
 
     fn on_disk_changed(&mut self, paths: &[PathBuf]) {
-        let outcome = self.workspace.reconcile(&mut self.engine, Some(paths));
-        if let Some(outcome) = outcome {
-            self.workspace.write(self.storage.root());
+        // the tree of the folder shows the disk
+        let in_folder: Vec<&PathBuf> = paths
+            .iter()
+            .filter(|path| {
+                self.workspace
+                    .folder
+                    .as_ref()
+                    .is_some_and(|f| path.starts_with(f))
+            })
+            .collect();
+        if !in_folder.is_empty() {
+            (self.emit)("folder-changed", to_json(&in_folder));
+        }
+        if let Some(outcome) = self.workspace.reconcile(&mut self.engine, Some(paths)) {
+            self.keep_workspace();
             self.persist();
             self.announce(Some(&outcome));
         }
     }
+
+    /// Runs `f`, which creates files (a new file, a copy, the result of a split...). Where they go
+    /// when they are saved is the folder of the files they come from (the selected ones, before
+    /// `f`), if it is in the open folder. `default_folder` says whether a file with nothing to
+    /// come from goes in the open folder: a new file does.
+    pub fn creating(
+        &mut self,
+        folder: Option<PathBuf>,
+        default_folder: bool,
+        f: impl FnOnce(&mut Engine) -> api::Outcome,
+    ) -> api::Outcome {
+        let selected: Vec<uuid::Uuid> = self
+            .engine
+            .selection()
+            .file_ids()
+            .into_iter()
+            .map(|gpx_engine::FileId(id)| id)
+            .collect();
+        let dir = folder
+            .map(|folder| crate::workspace::canonical(&folder))
+            .or_else(|| self.workspace.source_dir(&selected))
+            .or_else(|| {
+                default_folder
+                    .then(|| self.workspace.folder.clone())
+                    .flatten()
+            });
+        let outcome = f(&mut self.engine);
+        if let Some(dir) = dir {
+            self.workspace.inherit(outcome.added(), &dir);
+        }
+        self.keep_workspace();
+        self.persist();
+        outcome
+    }
 }
 
 fn to_json<T: Serialize>(value: &T) -> serde_json::Value {

tauri/src/tests.rs

@@ -363,3 +363,95 @@ fn a_file_opened_with_the_app_is_opened_selected_and_announced() {
     assert!(events.iter().any(|(name, _)| name == "workspace-changed"));
     std::fs::remove_dir_all(directory).unwrap();
 }
+
+#[test]
+fn files_are_opened_closed_and_made_in_a_folder() {
+    let app = App::new();
+    let folder = std::env::temp_dir().join(format!("gpx-tests-{}", uuid::Uuid::new_v4()));
+    std::fs::create_dir_all(&folder).unwrap();
+    let path = folder.join("track.gpx");
+    std::fs::copy("../gpx-rs/data/simple.gpx", &path).unwrap();
+
+    // opened from the disk, clean
+    let outcome = app.call("open_paths", json!({ "paths": [path] }));
+    assert_eq!(outcome["added"].as_array().unwrap().len(), 1);
+    let id = outcome["added"][0].as_str().unwrap().to_string();
+    let state = app.call("workspace_state", json!({}));
+    assert_eq!(state["files"][&id]["dirty"], false);
+    assert!(state["files"][&id]["path"].is_string());
+
+    // a new file made in a folder is written there, and is not linked to a place yet
+    let created = app.call(
+        "new_file",
+        json!({ "name": "route", "lng": 4.4, "lat": 50.8, "folder": folder }),
+    );
+    let new_id = created["added"][0].as_str().unwrap().to_string();
+    let state = app.call("workspace_state", json!({}));
+    assert_eq!(state["files"][&new_id]["dirty"], true);
+    assert!(state["files"][&new_id]["folder"].is_string());
+    assert!(state["files"][&new_id].get("path").is_none());
+
+    // the tree needs an open folder
+    assert_eq!(app.call("list_folder", json!({})), json!([]));
+
+    // closing: what is saved goes, what has edits stays unless it is discarded
+    app.call("close_files", json!({ "fileIds": [id, new_id] }));
+    assert_eq!(app.call("file_order", json!({})), json!([new_id]));
+    app.call(
+        "close_files",
+        json!({ "fileIds": [new_id], "unsaved": "discard" }),
+    );
+    assert_eq!(app.call("file_order", json!({})), json!([]));
+    std::fs::remove_dir_all(folder).unwrap();
+}
+
+/// A file that is open from outside of any folder follows the disk too.
+#[test]
+fn a_file_outside_the_open_folder_is_read_again_when_the_disk_changes() {
+    use std::sync::mpsc;
+    use std::time::Duration;
+
+    let (events, received) = mpsc::channel();
+    let directory = std::env::temp_dir().join(format!("gpx-store-{}", uuid::Uuid::new_v4()));
+    let state = crate::state::AppState::open(
+        directory.clone(),
+        std::sync::Arc::new(move |name, _| {
+            let _ = events.send(name.to_string());
+        }),
+    )
+    .unwrap();
+
+    let folder = std::env::temp_dir().join(format!("gpx-tests-{}", uuid::Uuid::new_v4()));
+    std::fs::create_dir_all(&folder).unwrap();
+    let path = folder.join("track.gpx");
+    std::fs::copy("../gpx-rs/data/simple.gpx", &path).unwrap();
+    let opened = path.clone();
+    let id = state.core(move |core| {
+        let outcome = core.workspace.open_files(&mut core.engine, &[opened], true);
+        core.keep_workspace();
+        outcome.added()[0].clone()
+    });
+    let id = uuid::Uuid::parse_str(&id).unwrap();
+    let name = |state: &crate::state::AppState| {
+        state.core(move |core| {
+            core.engine
+                .file_structure(&gpx_engine::FileId(id))
+                .map(|structure| structure.name.clone())
+        })
+    };
+    let before = name(&state);
+
+    std::fs::copy("../gpx-rs/data/with_time.gpx", &path).unwrap();
+    // the debounced watcher tells the frontend that the engine changed
+    let mut changed = false;
+    while let Ok(event) = received.recv_timeout(Duration::from_secs(10)) {
+        if event == "engine-changed" {
+            changed = true;
+            break;
+        }
+    }
+    assert!(changed, "the file was not read again");
+    assert_ne!(name(&state), before);
+    std::fs::remove_dir_all(folder).unwrap();
+    std::fs::remove_dir_all(directory).unwrap();
+}

website/src/lib/actions/file-actions.ts

@@ -4,8 +4,7 @@ import { get } from 'svelte/store';
 import { boundsManager } from '$lib/state/bounds';
 import { engine } from '$lib/engine';
 import { defaultFileName } from '$lib/actions/default-file-name';
-import { askUnsaved } from '$lib/components/file-list/unsaved-prompt.svelte';
-import { subfolder } from '$lib/engine/workspace';
+import { askOverwrite, askUnsaved } from '$lib/components/file-list/unsaved-prompt.svelte';
 import type { UnsavedChoice } from '$lib/engine';
 
 /** The name of a new file: the translated default name, numbered if other files have it. */
@@ -32,71 +31,119 @@ export async function openFiles() {
     }
 }
 
-/**
- * What to do with the files of the open folder that have unsaved changes, which the user is asked
- * when there are some: `undefined` when there are none, `'cancel'` when they do not want to go on.
- */
-async function askAboutUnsavedFiles(): Promise<UnsavedChoice | undefined | 'cancel'> {
-    const workspace = get(engine.workspace);
-    if (!workspace?.folder) {
-        return undefined;
-    }
+/** The names of files, to show them to the user. */
+function namesOf(ids: string[]): string[] {
     const files = get(engine.files);
-    const names = Object.entries(workspace.files)
-        // the files in the folder, and the new ones, which are saved in it
-        .filter(
-            ([, file]) =>
-                file.dirty &&
-                (file.path === undefined || subfolder(workspace.folder, file.path) !== undefined)
-        )
-        .map(([id]) => {
-            const file = files.get(id);
-            return file ? get(file).structure.name : id;
-        });
-    return names.length > 0 ? askUnsaved(names) : undefined;
+    return ids.map((id) => {
+        const file = files.get(id);
+        return file ? get(file).structure.name : id;
+    });
+}
+
+/** The ids among `ids` of the files that have changes that are not saved. */
+function unsavedAmong(ids: string[]): string[] {
+    const workspace = get(engine.workspace);
+    return ids.filter((id) => workspace?.files[id]?.dirty);
 }
 
 /**
- * Opens a folder, which is watched (the desktop app). The folder that was open is closed: the user
- * is asked what to do with its unsaved files.
+ * What to do with the files among `ids` that have unsaved changes, which the user is asked when
+ * there are some: `undefined` when there are none, `'cancel'` when they do not want to go on.
+ */
+async function askAboutUnsavedFiles(ids: string[]): Promise<UnsavedChoice | undefined | 'cancel'> {
+    const unsaved = unsavedAmong(ids);
+    return unsaved.length > 0 ? askUnsaved(namesOf(unsaved)) : undefined;
+}
+
+/** All the open files. */
+function allFileIds(): string[] {
+    return get(engine.order);
+}
+
+/**
+ * Opens a folder, which is watched (the desktop app). Its files are not opened, they are in its
+ * tree. The folder that was open is closed with its files: the user is asked what to do with the
+ * unsaved ones.
  */
 export async function openFolder() {
-    const unsaved = await askAboutUnsavedFiles();
-    if (unsaved === 'cancel') {
-        return;
-    }
-    const ids = await engine.openFolder(unsaved);
-    if (ids.length > 0) {
-        boundsManager.fitBoundsOnLoad(ids);
+    const unsaved = await askAboutUnsavedFiles(allFileIds());
+    if (unsaved !== 'cancel') {
+        await engine.openFolder(unsaved);
     }
 }
 
-/** Closes the open folder and its files: the user is asked what to do with the unsaved ones. */
+/** Closes the open folder and all the files: the user is asked what to do with the unsaved ones. */
 export async function closeFolder() {
-    const unsaved = await askAboutUnsavedFiles();
+    const unsaved = await askAboutUnsavedFiles(allFileIds());
     if (unsaved !== 'cancel') {
         await engine.closeFolder(unsaved);
     }
 }
 
+/** Closes files: the user is asked what to do with the ones that have unsaved changes. */
+export async function closeFiles(ids: string[]) {
+    if (ids.length === 0) {
+        return;
+    }
+    const unsaved = await askAboutUnsavedFiles(ids);
+    if (unsaved !== 'cancel') {
+        await engine.closeFiles(ids, unsaved);
+    }
+}
+
+/** Closes all the files. */
+export function closeAll() {
+    return closeFiles(allFileIds());
+}
+
+/**
+ * Writes files to the file system. The user is asked first about the ones whose file was also
+ * changed on the disk, which saving overwrites: they can take the disk instead of their changes.
+ */
+async function saveFiles(ids: string[]) {
+    if (ids.length === 0) {
+        return;
+    }
+    const workspace = get(engine.workspace);
+    const replaced = ids.filter((id) => workspace?.files[id]?.replaced);
+    if (replaced.length > 0) {
+        const choice = await askOverwrite(namesOf(replaced));
+        if (choice === 'cancel') {
+            return;
+        }
+        if (choice === 'reload') {
+            // they are the files on the disk now, there is nothing to save
+            await engine.reload(replaced);
+            ids = ids.filter((id) => !replaced.includes(id));
+        }
+    }
+    if (ids.length > 0) {
+        await engine.save(ids);
+    }
+}
+
 /** Saves the selected files to the file system, all the ones that have unsaved edits if none is. */
 export function saveSelected(selectedFileIds: string[]) {
-    const workspace = get(engine.workspace);
-    const ids =
-        selectedFileIds.length > 0
-            ? selectedFileIds
-            : Object.keys(workspace?.files ?? {}).filter((id) => workspace?.files[id].dirty);
-    if (ids.length > 0) {
-        engine.save(ids);
-    }
+    return saveFiles(selectedFileIds.length > 0 ? selectedFileIds : unsavedAmong(allFileIds()));
 }
 
 /** Saves all the files that have unsaved edits to the file system. */
 export function saveAll() {
-    const workspace = get(engine.workspace);
-    const ids = Object.keys(workspace?.files ?? {}).filter((id) => workspace?.files[id].dirty);
+    return saveFiles(unsavedAmong(allFileIds()));
+}
+
+/** Saves a file where the user says, which is where it is from then on (not for several files). */
+export async function saveAs(selectedFileIds: string[]) {
+    if (selectedFileIds.length === 1) {
+        await engine.saveAs(selectedFileIds[0]);
+    }
+}
+
+/** Opens a file of the tree of the open folder. */
+export async function openPath(path: string) {
+    const ids = await engine.openPaths([path]);
     if (ids.length > 0) {
-        engine.save(ids);
+        boundsManager.fitBoundsOnLoad(ids);
     }
 }
 

website/src/lib/components/Menu.svelte

@@ -40,6 +40,8 @@
         FolderOpen,
         FileStack,
         FileX,
+        Save,
+        SaveAll,
         BookOpenText,
         ChartArea,
         Maximize,
@@ -59,10 +61,22 @@
     import { languages } from '$lib/i18n/languages';
     import { getURLForLanguage } from '$lib/utils';
     import { settings } from '$lib/state/settings';
-    import { createFile, loadFiles, triggerFileInput } from '$lib/actions/file-actions';
+    import {
+        closeAll,
+        closeFiles,
+        closeFolder,
+        createFile,
+        loadFiles,
+        openFiles,
+        openFolder,
+        saveAll,
+        saveAs,
+        saveSelected,
+    } from '$lib/actions/file-actions';
+    import UnsavedDialog from '$lib/components/file-list/UnsavedDialog.svelte';
     import { engine } from '$lib/engine';
     import { allHidden } from '$lib/engine/all-hidden';
-    import { selectionSize } from '$lib/engine/selection-helpers';
+    import { selectedFileIds, selectionSize } from '$lib/engine/selection-helpers';
     import { boundsManager } from '$lib/state/bounds';
     import { onMount } from 'svelte';
 
@@ -82,10 +96,14 @@
         routing,
     } = settings;
 
-    const { files, selection, canUndo, canRedo, canPaste } = engine;
+    const { files, selection, canUndo, canRedo, canPaste, workspace } = engine;
 
     let selectionCount = $derived(selectionSize($selection));
     let noFiles = $derived($files.size === 0);
+    // the desktop app: the files are linked to the file system
+    let desktop = $derived($workspace !== undefined);
+    let selectedIds = $derived(selectedFileIds($selection));
+    let anyUnsaved = $derived(Object.values($workspace?.files ?? {}).some((file) => file.dirty));
     // metadata and style can be edited for files and tracks only
     let filesOrTracksSelected = $derived($selection.type === 'file' || $selection.type === 'track');
 
@@ -142,11 +160,18 @@
                         <Shortcut key="+" ctrl={true} />
                     </Menubar.Item>
                     <Menubar.Separator />
-                    <Menubar.Item onclick={triggerFileInput}>
+                    <Menubar.Item onclick={openFiles}>
                         <FolderOpen size="16" />
                         {i18n._('menu.open')}
                         <Shortcut key="O" ctrl={true} />
                     </Menubar.Item>
+                    {#if desktop}
+                        <Menubar.Item onclick={openFolder}>
+                            <FolderOpen size="16" />
+                            {i18n._('menu.open_folder')}
+                            <Shortcut key="O" ctrl={true} shift={true} />
+                        </Menubar.Item>
+                    {/if}
                     <Menubar.Separator />
                     <Menubar.Item onclick={() => engine.duplicate()} disabled={selectionCount == 0}>
                         <Copy size="16" />
@@ -154,19 +179,60 @@
                         <Shortcut key="D" ctrl={true} />
                     </Menubar.Item>
                     <Menubar.Separator />
-                    <Menubar.Item
-                        onclick={() => engine.delete(true)}
-                        disabled={selectionCount == 0}
-                    >
-                        <FileX size="16" />
-                        {i18n._('menu.delete')}
-                        <Shortcut key="⌫" ctrl={true} />
-                    </Menubar.Item>
-                    <Menubar.Item onclick={() => engine.deleteAll()} disabled={noFiles}>
-                        <FileX size="16" />
-                        {i18n._('menu.delete_all')}
-                        <Shortcut key="⌫" ctrl={true} shift={true} />
-                    </Menubar.Item>
+                    {#if desktop}
+                        <Menubar.Item
+                            onclick={() => saveSelected(selectedIds)}
+                            disabled={selectionCount == 0 && !anyUnsaved}
+                        >
+                            <Save size="16" />
+                            {i18n._('menu.save')}
+                            <Shortcut key="S" ctrl={true} />
+                        </Menubar.Item>
+                        <Menubar.Item onclick={saveAll} disabled={!anyUnsaved}>
+                            <Save size="16" />
+                            {i18n._('menu.save_all')}
+                            <Shortcut key="S" ctrl={true} shift={true} />
+                        </Menubar.Item>
+                        <Menubar.Item
+                            onclick={() => saveAs(selectedIds)}
+                            disabled={selectedIds.length !== 1}
+                        >
+                            <SaveAll size="16" />
+                            {i18n._('menu.save_as')}
+                        </Menubar.Item>
+                        <Menubar.Separator />
+                        <Menubar.Item
+                            onclick={() => closeFiles(selectedIds)}
+                            disabled={selectedIds.length === 0}
+                        >
+                            <FileX size="16" />
+                            {i18n._('menu.close')}
+                            <Shortcut key="W" ctrl={true} />
+                        </Menubar.Item>
+                        <Menubar.Item onclick={closeAll} disabled={noFiles}>
+                            <FileX size="16" />
+                            {i18n._('menu.close_all')}
+                            <Shortcut key="W" ctrl={true} shift={true} />
+                        </Menubar.Item>
+                        <Menubar.Item onclick={closeFolder} disabled={!$workspace?.folder}>
+                            <FileX size="16" />
+                            {i18n._('menu.close_folder')}
+                        </Menubar.Item>
+                    {:else}
+                        <Menubar.Item
+                            onclick={() => engine.delete(true)}
+                            disabled={selectionCount == 0}
+                        >
+                            <FileX size="16" />
+                            {i18n._('menu.delete')}
+                            <Shortcut key="⌫" ctrl={true} />
+                        </Menubar.Item>
+                        <Menubar.Item onclick={() => engine.deleteAll()} disabled={noFiles}>
+                            <FileX size="16" />
+                            {i18n._('menu.delete_all')}
+                            <Shortcut key="⌫" ctrl={true} shift={true} />
+                        </Menubar.Item>
+                    {/if}
                     <Menubar.Separator />
                     <Menubar.Item
                         onclick={() => (exportState.current = ExportState.SELECTION)}
@@ -174,7 +240,7 @@
                     >
                         <Download size="16" />
                         {i18n._('menu.export')}
-                        <Shortcut key="S" ctrl={true} />
+                        {#if !desktop}<Shortcut key="S" ctrl={true} />{/if}
                     </Menubar.Item>
                     <Menubar.Item
                         onclick={() => (exportState.current = ExportState.ALL)}
@@ -182,7 +248,7 @@
                     >
                         <Download size="16" />
                         {i18n._('menu.export_all')}
-                        <Shortcut key="S" ctrl={true} shift={true} />
+                        {#if !desktop}<Shortcut key="S" ctrl={true} shift={true} />{/if}
                     </Menubar.Item>
                 </Menubar.Content>
             </Menubar.Menu>
@@ -498,6 +564,7 @@
 </div>
 
 <Export />
+<UnsavedDialog />
 <LayerControlSettings bind:open={layerSettingsOpen} />
 
 <svelte:window
@@ -519,8 +586,26 @@
         if (e.key === '+' && (e.metaKey || e.ctrlKey)) {
             createFile();
             e.preventDefault();
-        } else if (e.key === 'o' && (e.metaKey || e.ctrlKey)) {
-            triggerFileInput();
+        } else if ((e.key === 'o' || e.key === 'O') && (e.metaKey || e.ctrlKey)) {
+            if (desktop && e.shiftKey) {
+                openFolder();
+            } else {
+                openFiles();
+            }
+            e.preventDefault();
+        } else if (desktop && (e.key === 'w' || e.key === 'W') && (e.metaKey || e.ctrlKey)) {
+            if (e.shiftKey) {
+                closeAll();
+            } else {
+                closeFiles(selectedIds);
+            }
+            e.preventDefault();
+        } else if (desktop && (e.key === 's' || e.key === 'S') && (e.metaKey || e.ctrlKey)) {
+            if (e.shiftKey) {
+                saveAll();
+            } else {
+                saveSelected(selectedIds);
+            }
             e.preventDefault();
         } else if (e.key === 'd' && (e.metaKey || e.ctrlKey)) {
             engine.duplicate();
@@ -557,7 +642,8 @@
             }
             e.preventDefault();
         } else if ((e.key === 'Backspace' || e.key === 'Delete') && (e.metaKey || e.ctrlKey)) {
-            if (!targetInput) {
+            // the desktop app closes files instead
+            if (!targetInput && !desktop) {
                 if (e.shiftKey) {
                     engine.deleteAll();
                 } else {

website/src/lib/components/export/utils.svelte.ts

@@ -31,6 +31,11 @@ export function allFileIds(): string[] {
 }
 
 async function exportFiles(fileIds: string[], options: ExportOptions) {
+    if (get(engine.workspace)) {
+        // the desktop app: the user chooses where the files go
+        await engine.exportFiles(fileIds, options);
+        return;
+    }
     const files = (
         await Promise.all(
             fileIds.map(async (fileId) => {

website/src/lib/components/file-list/UnsavedDialog.svelte

@@ -0,0 +1,69 @@
+<script lang="ts">
+    import * as AlertDialog from '$lib/components/ui/alert-dialog';
+    import { Button } from '$lib/components/ui/button';
+    import { i18n } from '$lib/i18n/i18n.svelte';
+    import { unsavedPrompt } from './unsaved-prompt.svelte';
+
+    let prompt = $derived(unsavedPrompt.current);
+
+    /** Closes the dialog, and gives the answer to whoever asked. */
+    function answer(choice: 'save' | 'discard' | 'reload' | 'cancel') {
+        const current = unsavedPrompt.current;
+        unsavedPrompt.current = undefined;
+        if (current?.kind === 'unsaved' && choice !== 'reload') {
+            current.resolve(choice);
+        } else if (current?.kind === 'overwrite') {
+            current.resolve(
+                choice === 'save' ? 'overwrite' : choice === 'reload' ? 'reload' : 'cancel'
+            );
+        }
+    }
+</script>
+
+<AlertDialog.Root
+    open={prompt !== undefined}
+    onOpenChange={(open) => {
+        if (!open) {
+            answer('cancel');
+        }
+    }}
+>
+    <AlertDialog.Content>
+        {#if prompt}
+            <AlertDialog.Header>
+                <AlertDialog.Title>
+                    {prompt.kind === 'unsaved'
+                        ? i18n._('menu.unsaved_title')
+                        : i18n._('menu.overwrite_title')}
+                </AlertDialog.Title>
+                <AlertDialog.Description>
+                    {prompt.kind === 'unsaved'
+                        ? i18n._('menu.unsaved_description')
+                        : i18n._('menu.overwrite_description')}
+                </AlertDialog.Description>
+            </AlertDialog.Header>
+            <ul class="list-disc pl-6 text-sm max-h-40 overflow-y-auto">
+                {#each prompt.names as name}
+                    <li>{name}</li>
+                {/each}
+            </ul>
+            <AlertDialog.Footer>
+                <Button variant="outline" onclick={() => answer('cancel')}>
+                    {i18n._('menu.cancel')}
+                </Button>
+                {#if prompt.kind === 'unsaved'}
+                    <Button variant="destructive" onclick={() => answer('discard')}>
+                        {i18n._('menu.discard')}
+                    </Button>
+                {:else}
+                    <Button variant="destructive" onclick={() => answer('reload')}>
+                        {i18n._('menu.reload')}
+                    </Button>
+                {/if}
+                <Button onclick={() => answer('save')}>
+                    {prompt.kind === 'unsaved' ? i18n._('menu.save') : i18n._('menu.overwrite')}
+                </Button>
+            </AlertDialog.Footer>
+        {/if}
+    </AlertDialog.Content>
+</AlertDialog.Root>

website/src/lib/components/file-list/unsaved-prompt.svelte.ts

@@ -0,0 +1,32 @@
+import type { UnsavedChoice } from '$lib/engine';
+
+type Prompt =
+    | { kind: 'unsaved'; names: string[]; resolve: (choice: UnsavedChoice | 'cancel') => void }
+    | {
+          kind: 'overwrite';
+          names: string[];
+          resolve: (choice: 'overwrite' | 'reload' | 'cancel') => void;
+      };
+
+/** The question that the user is asked, shown by `UnsavedDialog`. */
+export const unsavedPrompt: { current: Prompt | undefined } = $state({ current: undefined });
+
+/**
+ * Asks what to do with files that have unsaved changes when they are closed: save them, discard
+ * the changes, or `'cancel'` to keep going as before.
+ */
+export function askUnsaved(names: string[]): Promise<UnsavedChoice | 'cancel'> {
+    return new Promise((resolve) => {
+        unsavedPrompt.current = { kind: 'unsaved', names, resolve };
+    });
+}
+
+/**
+ * Asks what to do with files that have changes and were also changed on the disk: `'overwrite'` the
+ * disk, `'reload'` the disk (the changes are lost), or `'cancel'`.
+ */
+export function askOverwrite(names: string[]): Promise<'overwrite' | 'reload' | 'cancel'> {
+    return new Promise((resolve) => {
+        unsavedPrompt.current = { kind: 'overwrite', names, resolve };
+    });
+}

website/src/lib/engine/backend/tauri.ts

@@ -1,7 +1,7 @@
 import { invoke } from '@tauri-apps/api/core';
 import { listen } from '@tauri-apps/api/event';
 import type { Outcome, RouteAttributes, StorageOpened } from 'gpx-wasm';
-import type { Backend, WorkspaceState } from './types';
+import type { Backend, FolderEntry, WorkspaceState } from './types';
 
 /** An array that a command returns as its bytes. */
 const array = async <T>(
@@ -211,9 +211,16 @@ export async function createTauriBackend(): Promise<Backend> {
         desktop: {
             workspace: () => invoke<WorkspaceState>('workspace_state'),
             openFiles: () => invoke<Outcome>('open_files'),
+            openPaths: (paths) => invoke<Outcome>('open_paths', { paths }),
             openFolder: (unsaved) => invoke<Outcome>('open_folder', { unsaved }),
             closeFolder: (unsaved) => invoke<Outcome>('close_folder', { unsaved }),
-            saveFiles: (fileIds) => invoke('save_files', { fileIds }),
+            closeFiles: (fileIds, unsaved) => invoke<Outcome>('close_files', { fileIds, unsaved }),
+            saveFiles: (fileIds) => invoke<boolean>('save_files', { fileIds }),
+            saveFileAs: (fileId) => invoke<boolean>('save_file_as', { fileId }),
+            reloadFiles: (fileIds) => invoke<Outcome>('reload_files', { fileIds }),
+            exportFiles: (fileIds, options) =>
+                invoke<boolean>('export_files', { fileIds, options }),
+            listFolder: (path) => invoke<FolderEntry[]>('list_folder', { path }),
             listen: async (onEngineChanged, onWorkspaceChanged, onFilesOpened) => {
                 await listen<Outcome>('files-opened', (event) => onFilesOpened(event.payload));
                 await listen<Outcome>('engine-changed', (event) => onEngineChanged(event.payload));

website/src/lib/engine/backend/types.ts

@@ -10,16 +10,33 @@ import type {
     TrackpointDetails,
     WaypointDetails,
 } from 'gpx-wasm';
-import type { MergeType, SelectMode, SplitType } from '../types';
+import type { ExportOptions, MergeType, SelectMode, SplitType } from '../types';
 
 /** What the desktop app knows of a file of the engine and the file system. */
 export type FileStatus = {
     /** Where the file is on the disk, absent for a file that only is in the engine. */
     path?: string;
-    /** The file has edits that the file on the disk does not have (or is not on the disk). */
+    /**
+     * The folder where the file is written the first time it is saved, for a file that is not on
+     * the disk and comes from (or was made in) the open folder.
+     */
+    folder?: string;
+    /**
+     * The file is not the one on the disk: it has edits, is not on the disk, or the file on the
+     * disk is not the one that was read (it was replaced, or is gone).
+     */
     dirty: boolean;
-    /** The file on the disk was changed by something else while this one had edits. */
-    conflict: boolean;
+    /** The file on the disk was replaced by something else: saving overwrites it. */
+    replaced: boolean;
+    /** The file on the disk is gone. */
+    missing: boolean;
+};
+
+/** An entry of the tree of the open folder: a folder, or a GPX file. */
+export type FolderEntry = {
+    name: string;
+    path: string;
+    isDir: boolean;
 };
 
 /** What to do with the files of a folder that have unsaved edits when it is closed. */
@@ -39,22 +56,39 @@ export interface DesktopFiles {
     workspace(): Promise<WorkspaceState>;
     /** Opens the files that the user picks, which get selected. */
     openFiles(): Promise<Outcome>;
+    /** Opens files of the file system by their path, like the ones of the tree of the folder. */
+    openPaths(paths: string[]): Promise<Outcome>;
     /**
-     * Opens the folder that the user picks: its files are opened, and it is watched. The folder
-     * that was open is closed (see `closeFolder` for `unsaved`).
+     * Opens the folder that the user picks, which is watched. Its files are not opened: they are
+     * in its tree (`listFolder`). The folder that was open is closed with its files (see
+     * `closeFiles` for `unsaved`).
      */
     openFolder(unsaved?: UnsavedChoice): Promise<Outcome>;
-    /**
-     * Closes the open folder: it is not watched anymore, and its files are closed. What to do with
-     * the ones that have unsaved edits: `save` them first, `discard` the edits, or keep them open
-     * when it is not said. Rejects, and closes nothing, if they could not be saved.
-     */
+    /** Closes the open folder: it is not watched anymore, and its files are closed. */
     closeFolder(unsaved?: UnsavedChoice): Promise<Outcome>;
     /**
-     * Writes files to the disk, replacing what is there (the user is asked where to put the ones
-     * that are not on the disk yet).
+     * Closes files. What to do with the ones that have unsaved edits: `save` them first (the user
+     * is asked where to put the ones that have no place), `discard` the edits, or keep them open
+     * when it is not said.
      */
-    saveFiles(fileIds: string[]): Promise<void>;
+    closeFiles(fileIds: string[], unsaved?: UnsavedChoice): Promise<Outcome>;
+    /**
+     * Writes files to the disk, replacing what is there (the user is asked where to put the ones
+     * that have no place: a file, or a folder for several of them). Resolves to false if the user
+     * cancelled.
+     */
+    saveFiles(fileIds: string[]): Promise<boolean>;
+    /** Writes a file where the user says, which is where it is from then on. False if cancelled. */
+    saveFileAs(fileId: string): Promise<boolean>;
+    /** Reads files again from the disk: their edits are lost (one undo step). */
+    reloadFiles(fileIds: string[]): Promise<Outcome>;
+    /**
+     * Writes copies of files where the user says (a file, or a folder for several). The files stay
+     * as they are. False if the user cancelled.
+     */
+    exportFiles(fileIds: string[], options: ExportOptions): Promise<boolean>;
+    /** The folders and GPX files in a folder of the open folder (the open folder by default). */
+    listFolder(path?: string): Promise<FolderEntry[]>;
     /**
      * Tells when the engine changed without being asked, because the files on the disk did (the
      * outcome to apply), when the status of the files changed, and when files were opened with the

website/src/lib/engine/engine.ts

@@ -11,6 +11,7 @@ import { categoryIntervals } from '$lib/engine/trackpoint-categories';
 import { selectedElementIds, type FileTreeNode } from '$lib/engine/selection-helpers';
 import type { RouteAttributes } from 'gpx-wasm';
 import { loadBackend, type Backend } from './backend';
+import type { DesktopFiles } from './backend/types';
 import { readFileState } from './file-state';
 import { StatisticsReader } from './statistics';
 import { openStoredFiles } from './storage';
@@ -29,6 +30,7 @@ import {
     type SelectMode,
     type SplitType,
     type StatisticsRequest,
+    type FolderEntry,
     type UnsavedChoice,
     type WorkspaceState,
     type TrackpointDetails,
@@ -554,41 +556,88 @@ class Engine {
         return this.addedBy((b) => b.desktop!.openFiles());
     }
 
-    /**
-     * Opens the folder that the user picks (instead of the one that was open, which is closed like
-     * `closeFolder` does, `unsaved` being what to do with its unsaved files): its files are opened,
-     * and it is watched: the files that appear, change or disappear in it are brought in the engine.
-     * New files are saved in it. Resolves to the ids of the files that were added.
-     */
-    async openFolder(unsaved?: UnsavedChoice): Promise<string[]> {
-        return this.addedBy((b) => b.desktop!.openFolder(unsaved));
+    /** Opens files of the file system by their path, which get selected. Resolves to the new ids. */
+    async openPaths(paths: string[]): Promise<string[]> {
+        return this.addedBy((b) => b.desktop!.openPaths(paths));
     }
 
     /**
-     * Closes the open folder: it is not watched anymore, and its files are closed. `unsaved` says
-     * what to do with the ones that have unsaved edits: they are saved first, or their edits are
-     * discarded (they stay open when it is not said).
+     * Opens the folder that the user picks (instead of the one that was open, which is closed with
+     * its files like `closeFiles` does, `unsaved` being what to do with the unsaved ones). The
+     * folder is watched, and its tree is read with `listFolder`: its files are not opened.
      */
+    async openFolder(unsaved?: UnsavedChoice) {
+        await this.run((b) => b.desktop!.openFolder(unsaved));
+        await this.enqueue(async () => this.refreshWorkspace(this.backend!));
+    }
+
+    /** Closes the open folder and all the files: see `closeFiles` for `unsaved`. */
     async closeFolder(unsaved?: UnsavedChoice) {
         await this.run((b) => b.desktop!.closeFolder(unsaved));
         await this.enqueue(async () => this.refreshWorkspace(this.backend!));
     }
 
     /**
-     * Writes files to the file system, replacing what is there; they are not edited anymore from
-     * then on. The user is asked where to put the ones that are not on the file system yet.
+     * Closes files. `unsaved` says what to do with the ones that have unsaved edits: they are saved
+     * first, or their edits are lost (they stay open when it is not said).
      */
-    async save(fileIds: string[]) {
+    async closeFiles(fileIds: string[], unsaved?: UnsavedChoice) {
+        await this.run((b) => b.desktop!.closeFiles(fileIds, unsaved));
+        await this.enqueue(async () => this.refreshWorkspace(this.backend!));
+    }
+
+    /**
+     * Writes files to the file system, replacing what is there; they are not edited anymore from
+     * then on. The user is asked where to put the ones that have no place yet. Resolves to false
+     * when the user cancelled or the files could not be saved.
+     */
+    async save(fileIds: string[]): Promise<boolean> {
+        return this.desktopCall((desktop) => desktop.saveFiles(fileIds));
+    }
+
+    /** Writes a file where the user says, which is where it is from then on. */
+    async saveAs(fileId: string): Promise<boolean> {
+        return this.desktopCall((desktop) => desktop.saveFileAs(fileId));
+    }
+
+    /** Writes copies of files where the user says. The files stay as they are. */
+    async exportFiles(fileIds: string[], options: ExportOptions): Promise<boolean> {
+        return this.desktopCall((desktop) => desktop.exportFiles(fileIds, options));
+    }
+
+    /** Reads files again from the file system: their edits are lost (one undo step). */
+    async reload(fileIds: string[]) {
+        await this.run((b) => b.desktop!.reloadFiles(fileIds));
+        await this.enqueue(async () => this.refreshWorkspace(this.backend!));
+    }
+
+    /** The folders and GPX files in a folder of the open folder (the open folder by default). */
+    async listFolder(path?: string): Promise<FolderEntry[]> {
         await this.ready;
-        await this.enqueue(async () => {
-            const backend = this.backend!;
+        return this.enqueue(async () => {
             try {
-                await backend.desktop!.saveFiles(fileIds);
+                return await this.backend!.desktop!.listFolder(path);
             } catch (error) {
-                console.error('The files could not be saved', error);
+                console.error('The folder could not be read', error);
+                return [];
+            }
+        });
+    }
+
+    /** Calls the file system of the desktop app, and keeps the status of the files up to date. */
+    private async desktopCall(call: (desktop: DesktopFiles) => Promise<boolean>): Promise<boolean> {
+        await this.ready;
+        return this.enqueue(async () => {
+            const backend = this.backend!;
+            let done = false;
+            try {
+                done = await call(backend.desktop!);
+            } catch (error) {
+                console.error('The files could not be written', error);
                 this._lastError.set(String(error));
             }
             await this.refreshWorkspace(backend);
+            return done;
         });
     }
 

website/src/lib/engine/types.ts

@@ -4,7 +4,7 @@ import type { Visibility } from '$lib/engine/file-visibility';
 import type { CategoryIntervals } from '$lib/engine/trackpoint-categories';
 import type { FileStructure, GlobalStatistics } from 'gpx-wasm';
 
-export type { FileStatus, UnsavedChoice, WorkspaceState } from './backend/types';
+export type { FileStatus, FolderEntry, UnsavedChoice, WorkspaceState } from './backend/types';
 
 export type {
     Clipboard,

website/src/locales/en.json

@@ -13,6 +13,21 @@
         "new_track": "New track",
         "new_segment": "New segment",
         "open": "Open...",
+        "open_folder": "Open folder...",
+        "save": "Save",
+        "save_all": "Save all",
+        "save_as": "Save as...",
+        "close": "Close",
+        "close_all": "Close all",
+        "close_folder": "Close folder",
+        "reload": "Reload from disk",
+        "discard": "Discard",
+        "cancel": "Cancel",
+        "overwrite": "Overwrite",
+        "unsaved_title": "Unsaved changes",
+        "unsaved_description": "These files have changes that are not saved:",
+        "overwrite_title": "Overwrite changes made elsewhere?",
+        "overwrite_description": "These files have changes, and were also changed on the disk. Overwrite what is on the disk, or reload it and lose your changes?",
         "duplicate": "Duplicate",
         "copy": "Copy",
         "paste": "Paste",