progress

tauri/src/commands/edit.rs

@@ -0,0 +1,246 @@
+//! Editing the metadata, the style, the structure and the waypoints of the files, and the tools:
+//! reversing, cropping, reducing, timestamps, merging, cleaning...
+
+use gpx_engine::{self as engine, Command, LngLat, LngLatBounds};
+use tauri::State;
+use uuid::Uuid;
+
+use crate::dto::*;
+use crate::state::{act, edit, AppState};
+
+#[tauri::command(async)]
+pub fn metadata(state: State<AppState>, name: String, desc: String) -> Outcome {
+    edit!(
+        state,
+        Command::Metadata(engine::Metadata {
+            name: &name,
+            desc: &desc,
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn style(
+    state: State<AppState>,
+    color: Option<String>,
+    opacity: Option<f64>,
+    width: Option<f64>,
+) -> Outcome {
+    edit!(
+        state,
+        Command::Style(engine::Style {
+            color: color.as_deref(),
+            opacity,
+            width,
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn new_track(state: State<AppState>) -> Outcome {
+    edit!(state, Command::NewTrack(engine::NewTrack))
+}
+
+#[tauri::command(async)]
+pub fn new_track_segment(state: State<AppState>) -> Outcome {
+    edit!(state, Command::NewTrackSegment(engine::NewTrackSegment))
+}
+
+// Waypoints
+
+#[tauri::command(async)]
+#[allow(clippy::too_many_arguments)]
+pub fn new_waypoint(
+    state: State<AppState>,
+    lng: f64,
+    lat: f64,
+    ele: f64,
+    name: String,
+    desc: String,
+    icon: String,
+    link: String,
+) -> Outcome {
+    edit!(
+        state,
+        Command::NewWaypoint(engine::NewWaypoint {
+            lng,
+            lat,
+            ele,
+            name: &name,
+            desc: &desc,
+            icon: &icon,
+            link: &link,
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn move_waypoint(
+    state: State<AppState>,
+    file_id: Uuid,
+    waypoint_id: Uuid,
+    lng: f64,
+    lat: f64,
+    ele: f64,
+) -> Outcome {
+    edit!(
+        state,
+        Command::MoveWaypoint(engine::MoveWaypoint {
+            file_id: engine::FileId(file_id),
+            waypoint_id: engine::WaypointId(waypoint_id),
+            lng,
+            lat,
+            ele,
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn delete_waypoint(state: State<AppState>, file_id: Uuid, waypoint_id: Uuid) -> Outcome {
+    edit!(
+        state,
+        Command::DeleteWaypoint(engine::DeleteWaypoint {
+            file_id: engine::FileId(file_id),
+            waypoint_id: engine::WaypointId(waypoint_id),
+        })
+    )
+}
+
+#[tauri::command(async)]
+#[allow(clippy::too_many_arguments)]
+pub fn update_waypoint(
+    state: State<AppState>,
+    file_id: Uuid,
+    waypoint_id: Uuid,
+    lng: f64,
+    lat: f64,
+    ele: f64,
+    name: String,
+    desc: String,
+    icon: String,
+    link: String,
+) -> Outcome {
+    edit!(
+        state,
+        Command::EditWaypoint(engine::EditWaypoint {
+            file_id: engine::FileId(file_id),
+            waypoint_id: engine::WaypointId(waypoint_id),
+            lng,
+            lat,
+            ele,
+            name: &name,
+            desc: &desc,
+            icon: &icon,
+            link: &link,
+        })
+    )
+}
+
+// Tools
+
+#[tauri::command(async)]
+pub fn reverse(state: State<AppState>) -> Outcome {
+    edit!(state, Command::Reverse(engine::Reverse))
+}
+
+#[tauri::command(async)]
+pub fn round_trip(state: State<AppState>) -> Outcome {
+    edit!(state, Command::RoundTrip(engine::RoundTrip))
+}
+
+#[tauri::command(async)]
+pub fn crop(state: State<AppState>, start: u32, end: u32) -> Outcome {
+    if start > end {
+        return Outcome::failed(format!("the range {start}..{end} is reversed"));
+    }
+    edit!(state, Command::Crop(engine::Crop { start, end }))
+}
+
+#[tauri::command(async)]
+pub fn reduce(state: State<AppState>, tolerance: f64) -> Outcome {
+    edit!(state, Command::Reduce(engine::Reduce { tolerance }))
+}
+
+#[tauri::command(async)]
+pub fn change_timestamps(
+    state: State<AppState>,
+    start_time: f64,
+    speed: f64,
+    ratio: f64,
+) -> Outcome {
+    edit!(
+        state,
+        Command::Time(engine::Time {
+            start_time: start_time as i64,
+            kind: engine::TimeKind::Change { speed, ratio },
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn create_artificial_timestamps(
+    state: State<AppState>,
+    start_time: f64,
+    total_time: f64,
+) -> Outcome {
+    edit!(
+        state,
+        Command::Time(engine::Time {
+            start_time: start_time as i64,
+            kind: engine::TimeKind::Artificial { total_time },
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn merge(state: State<AppState>, merge_type: MergeType, remove_gaps: bool) -> Outcome {
+    edit!(
+        state,
+        Command::Merge(engine::Merge {
+            type_: merge_type.into(),
+            remove_gaps,
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn extract(state: State<AppState>) -> Outcome {
+    edit!(state, Command::Extract(engine::Extract))
+}
+
+#[tauri::command(async)]
+pub fn elevation(state: State<AppState>, ele: Vec<f64>) -> Outcome {
+    edit!(state, Command::Elevation(engine::Elevation { ele: &ele }))
+}
+
+#[tauri::command(async)]
+#[allow(clippy::too_many_arguments)]
+pub fn clean(
+    state: State<AppState>,
+    west: f64,
+    south: f64,
+    east: f64,
+    north: f64,
+    clean_type: CleanType,
+    trkpt: bool,
+    wpt: bool,
+) -> Outcome {
+    edit!(
+        state,
+        Command::Clean(engine::Clean {
+            bounds: LngLatBounds {
+                sw: LngLat {
+                    lng: west,
+                    lat: south,
+                },
+                ne: LngLat {
+                    lng: east,
+                    lat: north,
+                },
+            },
+            type_: clean_type.into(),
+            trkpt,
+            wpt,
+        })
+    )
+}

tauri/src/commands/files.rs

@@ -0,0 +1,161 @@
+//! Creating, loading, deleting, moving, copying and pasting files and their elements, and undoing.
+
+use gpx_engine::{self as engine, Action, Command};
+use tauri::ipc::{InvokeBody, Request};
+use tauri::State;
+use uuid::Uuid;
+
+use crate::dto::*;
+use crate::state::{act, edit, AppState};
+
+#[tauri::command(async)]
+pub fn new_file(
+    state: State<AppState>,
+    name: String,
+    lng: Option<f64>,
+    lat: Option<f64>,
+    ele: Option<f64>,
+) -> Outcome {
+    let trackpoint = lng.zip(lat).map(|(lng, lat)| engine::NewTrackpoint {
+        lng,
+        lat,
+        ele: ele.unwrap_or_default(),
+    });
+    edit!(
+        state,
+        Command::New(engine::New {
+            name: &name,
+            trackpoint,
+        })
+    )
+}
+
+/// The files are in the body, one after the other, the headers `lengths` and `names` (JSON) telling
+/// the number of bytes and the name of each one.
+#[tauri::command(async)]
+pub fn load_files(state: State<AppState>, request: Request<'_>) -> Outcome {
+    let InvokeBody::Raw(data) = request.body() else {
+        return Outcome::failed("the files are missing");
+    };
+    let header = |key: &str| {
+        request
+            .headers()
+            .get(key)
+            .and_then(|value| value.to_str().ok())
+            .and_then(urlencoding_decode)
+    };
+    let (Some(lengths), Some(names)) = (
+        header("lengths").and_then(|json| serde_json::from_str::<Vec<usize>>(&json).ok()),
+        header("names").and_then(|json| serde_json::from_str::<Vec<String>>(&json).ok()),
+    ) else {
+        return Outcome::failed("the lengths or the names of the files are not valid");
+    };
+    if lengths.len() != names.len() {
+        return Outcome::failed(format!(
+            "{} lengths for {} names",
+            lengths.len(),
+            names.len()
+        ));
+    }
+    let (data, mut offset) = (data.clone(), 0);
+    let mut ranges = Vec::with_capacity(names.len());
+    for (length, name) in lengths.iter().zip(&names) {
+        let end = offset + length;
+        if end > data.len() {
+            return Outcome::failed(format!("the data of {name} is shorter than its length"));
+        }
+        ranges.push(offset..end);
+        offset = end;
+    }
+    edit!(state, {
+        let files = ranges
+            .into_iter()
+            .zip(&names)
+            .map(|(range, name)| engine::Load {
+                data: &data[range],
+                name,
+            })
+            .collect();
+        Command::LoadFiles(engine::LoadFiles { files })
+    })
+}
+
+/// Headers are ASCII: the frontend percent-encodes the JSON.
+fn urlencoding_decode(value: &str) -> Option<String> {
+    let bytes = value.as_bytes();
+    let mut decoded = Vec::with_capacity(bytes.len());
+    let mut i = 0;
+    while i < bytes.len() {
+        if bytes[i] == b'%' {
+            let hex = value.get(i + 1..i + 3)?;
+            decoded.push(u8::from_str_radix(hex, 16).ok()?);
+            i += 3;
+        } else {
+            decoded.push(bytes[i]);
+            i += 1;
+        }
+    }
+    String::from_utf8(decoded).ok()
+}
+
+#[tauri::command(async)]
+pub fn duplicate(state: State<AppState>) -> Outcome {
+    edit!(state, Command::Duplicate(engine::Duplicate))
+}
+
+#[tauri::command(async)]
+pub fn delete(state: State<AppState>, whole_files: bool) -> Outcome {
+    edit!(state, Command::Delete(engine::Delete { whole_files }))
+}
+
+#[tauri::command(async)]
+pub fn delete_all(state: State<AppState>) -> Outcome {
+    edit!(state, Command::DeleteAll(engine::DeleteAll))
+}
+
+#[tauri::command(async)]
+pub fn reorder(state: State<AppState>, file_ids: Vec<Uuid>, index: usize) -> Outcome {
+    act!(
+        state,
+        Action::Reorder {
+            file_ids: file_ids.into_iter().map(engine::FileId).collect(),
+            index,
+        }
+    )
+}
+
+#[tauri::command(async)]
+pub fn copy(state: State<AppState>) -> Outcome {
+    act!(state, Action::Copy)
+}
+
+#[tauri::command(async)]
+pub fn cut(state: State<AppState>) -> Outcome {
+    act!(state, Action::Cut)
+}
+
+#[tauri::command(async)]
+pub fn paste(state: State<AppState>) -> Outcome {
+    edit!(state, Command::Paste(engine::Paste))
+}
+
+#[tauri::command(async)]
+pub fn move_elements(state: State<AppState>, what: Selection, to: MoveTarget) -> Outcome {
+    edit!(
+        state,
+        Command::Move(engine::Move {
+            what: what.into(),
+            to: to.into(),
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn undo(state: State<AppState>) -> Outcome {
+    act!(state, Action::Undo)
+}
+
+#[tauri::command(async)]
+pub fn redo(state: State<AppState>) -> Outcome {
+    act!(state, Action::Redo)
+}

tauri/src/commands/mod.rs

@@ -0,0 +1,14 @@
+//! The functions of the frontend's interface to the engine, as Tauri commands. They are the
+//! counterparts of the functions that `gpx-rs/wasm` exports, and cross the same data: see
+//! `website/src/lib/engine/backend`.
+//!
+//! The commands that edit the files or change the selection return an `Outcome`.
+//! They are `async` (so they run off the main thread), the frontend sends them one after the other.
+
+pub mod edit;
+pub mod files;
+pub mod queries;
+pub mod routing;
+pub mod selection;
+pub mod statistics;
+pub mod storage;

tauri/src/commands/queries.rs

@@ -0,0 +1,136 @@
+//! The files, their structure and statistics, the selection, the clipboard, and the coordinates of
+//! the trackpoints and waypoints (flat `[lng, lat, ...]` little-endian `f64` arrays).
+
+use gpx_engine::{self as engine, FileId};
+use tauri::State;
+use uuid::Uuid;
+
+use crate::dto::*;
+use crate::state::AppState;
+
+#[tauri::command(async)]
+pub fn file_order(state: State<AppState>) -> Vec<String> {
+    state.read(|e| ids(e.order()))
+}
+
+#[tauri::command(async)]
+pub fn file_structure(state: State<AppState>, file_id: Uuid) -> Option<FileStructure> {
+    state.read(move |e| e.file_structure(&FileId(file_id)).map(FileStructure::new))
+}
+
+#[tauri::command(async)]
+pub fn file_statistics(state: State<AppState>, file_id: Uuid) -> Option<GlobalStatistics> {
+    state.read(move |e| {
+        e.file_statistics(&FileId(file_id))
+            .map(|s| GlobalStatistics::new(&s))
+    })
+}
+
+#[tauri::command(async)]
+pub fn selection(state: State<AppState>) -> Selection {
+    state.read(|e| e.selection().into())
+}
+
+#[tauri::command(async)]
+pub fn clipboard(state: State<AppState>) -> Option<Clipboard> {
+    state.read(|e| e.clipboard().map(Clipboard::new))
+}
+
+#[tauri::command(async)]
+pub fn can_undo(state: State<AppState>) -> bool {
+    state.read(|e| e.can_undo())
+}
+
+#[tauri::command(async)]
+pub fn can_redo(state: State<AppState>) -> bool {
+    state.read(|e| e.can_redo())
+}
+
+#[tauri::command(async)]
+pub fn can_paste(state: State<AppState>) -> bool {
+    state.read(|e| e.can_paste())
+}
+
+#[tauri::command(async)]
+pub fn waypoint(
+    state: State<AppState>,
+    file_id: Uuid,
+    waypoint_id: Uuid,
+) -> Option<WaypointDetails> {
+    state.read(move |e| {
+        e.waypoint(&FileId(file_id), &engine::WaypointId(waypoint_id))
+            .map(WaypointDetails::new)
+    })
+}
+
+#[tauri::command(async)]
+pub fn trackpoint(
+    state: State<AppState>,
+    file_id: Uuid,
+    segment_id: Uuid,
+    index: usize,
+) -> Option<TrackpointDetails> {
+    state.read(move |e| {
+        e.trackpoint(&FileId(file_id), &engine::TrackSegmentId(segment_id), index)
+            .map(TrackpointDetails::new)
+    })
+}
+
+/// A file as GPX (UTF-8 bytes), the first byte telling whether the file exists.
+#[tauri::command(async)]
+#[allow(clippy::too_many_arguments)]
+pub fn export_file(
+    state: State<AppState>,
+    file_id: Uuid,
+    time: bool,
+    hr: bool,
+    cad: bool,
+    atemp: bool,
+    power: bool,
+    osm: bool,
+    as_route: bool,
+) -> Bytes {
+    let options = engine::ExportOptions {
+        time,
+        hr,
+        cad,
+        atemp,
+        power,
+        osm,
+        as_route,
+    };
+    optional(state.read(move |e| e.export(&FileId(file_id), options)))
+}
+
+/// The data that some files have: a bit for the time (1), heart rate (2), cadence (4), temperature
+/// (8), power (16) and the OpenStreetMap data (32).
+#[tauri::command(async)]
+pub fn exportable_data(state: State<AppState>, file_ids: Vec<Uuid>) -> u8 {
+    state.read(move |e| {
+        let ids: Vec<FileId> = file_ids.into_iter().map(FileId).collect();
+        let data = e.exportable_data(&ids);
+        [
+            data.time, data.hr, data.cad, data.atemp, data.power, data.osm,
+        ]
+        .iter()
+        .enumerate()
+        .fold(0, |bits, (i, on)| bits | (u8::from(*on) << i))
+    })
+}
+
+#[tauri::command(async)]
+pub fn reduction_distances(state: State<AppState>) -> Bytes {
+    Bytes::new(state.read(|e| f64s(&e.reduction_distances())))
+}
+
+#[tauri::command(async)]
+pub fn segment_coordinates(state: State<AppState>, segment_id: Uuid) -> Bytes {
+    Bytes::new(
+        state.read(move |e| f64s(e.segment_coordinates(&engine::TrackSegmentId(segment_id)))),
+    )
+}
+
+#[tauri::command(async)]
+pub fn waypoint_coordinates(state: State<AppState>, file_id: Uuid) -> Bytes {
+    Bytes::new(state.read(move |e| f64s(e.waypoint_coordinates(&FileId(file_id)))))
+}

tauri/src/commands/routing.rs

@@ -0,0 +1,73 @@
+//! The commands that refer to trackpoints by their index in the routing buffers, which only mean
+//! something for the `revision` they were read with: the commands do nothing if the selection is
+//! not the one of that revision anymore.
+
+use gpx_engine::{self as engine, Command};
+use tauri::State;
+
+use crate::dto::*;
+use crate::state::{edit_at, AppState};
+
+#[tauri::command(async)]
+#[allow(clippy::too_many_arguments)]
+pub fn route(
+    state: State<AppState>,
+    revision: u32,
+    start: u32,
+    end: u32,
+    lng: Vec<f64>,
+    lat: Vec<f64>,
+    ele: Vec<f64>,
+    attributes: RouteAttributes,
+    anchors: Vec<u32>,
+) -> Outcome {
+    if lng.len() != lat.len() || lat.len() != ele.len() {
+        return Outcome::failed("lng, lat and ele differ in length");
+    }
+    edit_at!(
+        state,
+        revision,
+        Command::Route(engine::Route {
+            start,
+            end,
+            lng: &lng,
+            lat: &lat,
+            ele: &ele,
+            surface: attributes.surface.view(),
+            highway: attributes.highway.view(),
+            sac_scale: attributes.sac_scale.view(),
+            mtb_scale: attributes.mtb_scale.view(),
+            anchors: &anchors,
+        })
+    )
+}
+
+#[tauri::command(async)]
+pub fn insert_anchor(state: State<AppState>, revision: u32, lng: f64, lat: f64) -> Outcome {
+    edit_at!(
+        state,
+        revision,
+        Command::InsertAnchor(engine::InsertAnchor { lng, lat })
+    )
+}
+
+#[tauri::command(async)]
+pub fn change_loop_start(state: State<AppState>, revision: u32, index: u32) -> Outcome {
+    edit_at!(
+        state,
+        revision,
+        Command::ChangeLoopStart(engine::ChangeLoopStart { index })
+    )
+}
+
+#[tauri::command(async)]
+pub fn split(state: State<AppState>, revision: u32, at: u32, split_type: SplitType) -> Outcome {
+    edit_at!(
+        state,
+        revision,
+        Command::Split(engine::Split {
+            at,
+            split_type: split_type.into(),
+        })
+    )
+}

tauri/src/commands/selection.rs

@@ -0,0 +1,102 @@
+//! Changing what is selected.
+
+use gpx_engine::{self as engine, Action};
+use tauri::State;
+use uuid::Uuid;
+
+use crate::dto::*;
+use crate::state::{act, AppState};
+
+fn select_elements(
+    state: &AppState,
+    selection: Option<engine::Selection>,
+    mode: SelectMode,
+) -> Outcome {
+    match selection {
+        Some(selection) => act!(
+            state,
+            Action::Select {
+                selection,
+                mode: mode.into(),
+            }
+        ),
+        None => Outcome::failed("the ids are not UUIDs"),
+    }
+}
+
+fn to_file_ids(ids: Vec<Uuid>) -> Vec<engine::FileId> {
+    ids.into_iter().map(engine::FileId).collect()
+}
+
+#[tauri::command(async)]
+pub fn select(state: State<AppState>, file_ids: Vec<Uuid>, mode: SelectMode) -> Outcome {
+    let selection = engine::Selection::File {
+        file_ids: to_file_ids(file_ids).into_iter().collect(),
+    };
+    select_elements(&state, Some(selection), mode)
+}
+
+#[tauri::command(async)]
+pub fn select_all(state: State<AppState>) -> Outcome {
+    act!(state, Action::SelectAll)
+}
+
+#[tauri::command(async)]
+pub fn arrow_select(state: State<AppState>, down: bool, add: bool) -> Outcome {
+    act!(state, Action::ArrowSelect { down, add })
+}
+
+#[tauri::command(async)]
+pub fn select_tracks(
+    state: State<AppState>,
+    file_id: Uuid,
+    track_ids: Vec<Uuid>,
+    mode: SelectMode,
+) -> Outcome {
+    let selection = engine::Selection::Track {
+        file_id: engine::FileId(file_id),
+        trk_ids: track_ids.into_iter().map(engine::TrackId).collect(),
+    };
+    select_elements(&state, Some(selection), mode)
+}
+
+#[tauri::command(async)]
+pub fn select_segments(
+    state: State<AppState>,
+    file_id: Uuid,
+    track_id: Uuid,
+    segment_ids: Vec<Uuid>,
+    mode: SelectMode,
+) -> Outcome {
+    let selection = engine::Selection::TrackSegment {
+        file_id: engine::FileId(file_id),
+        trk_id: engine::TrackId(track_id),
+        trkseg_ids: segment_ids
+            .into_iter()
+            .map(engine::TrackSegmentId)
+            .collect(),
+    };
+    select_elements(&state, Some(selection), mode)
+}
+
+#[tauri::command(async)]
+pub fn select_waypoint_group(state: State<AppState>, file_id: Uuid, mode: SelectMode) -> Outcome {
+    let selection = engine::Selection::Waypoints {
+        file_id: engine::FileId(file_id),
+    };
+    select_elements(&state, Some(selection), mode)
+}
+
+#[tauri::command(async)]
+pub fn select_waypoints(
+    state: State<AppState>,
+    file_id: Uuid,
+    waypoint_ids: Vec<Uuid>,
+    mode: SelectMode,
+) -> Outcome {
+    let selection = engine::Selection::Waypoint {
+        file_id: engine::FileId(file_id),
+        wpt_ids: waypoint_ids.into_iter().map(engine::WaypointId).collect(),
+    };
+    select_elements(&state, Some(selection), mode)
+}

tauri/src/commands/statistics.rs

@@ -0,0 +1,135 @@
+//! The statistics of the selection and the anchors of the routing tool, as little-endian arrays
+//! (one per call, copies of the buffers of the engine). Optional ones start with a byte telling
+//! whether they are there.
+
+use tauri::State;
+
+use crate::dto::*;
+use crate::state::AppState;
+
+macro_rules! f64_getters {
+    ($($name:ident),*) => {$(
+        #[tauri::command(async)]
+        pub fn $name(state: State<AppState>) -> Bytes {
+            Bytes::new(state.read(|e| f64s(&e.statistics().$name)))
+        }
+    )*};
+}
+
+f64_getters!(
+    total_distance,
+    slope,
+    slope_segment_slope,
+    slope_segment_distance,
+    lng,
+    lat,
+    ele
+);
+
+macro_rules! optional_f64_getters {
+    ($($name:ident),*) => {$(
+        #[tauri::command(async)]
+        pub fn $name(state: State<AppState>) -> Bytes {
+            optional(state.read(|e| e.statistics().$name.as_deref().map(f64s)))
+        }
+    )*};
+}
+
+optional_f64_getters!(speed, hr, cad, atemp, power);
+
+/// Timestamps in milliseconds since the epoch (`NO_TIME` when missing), as `i64`.
+#[tauri::command(async)]
+pub fn timestamps(state: State<AppState>) -> Bytes {
+    optional(state.read(|e| e.statistics().time.as_deref().map(i64s)))
+}
+
+#[tauri::command(async)]
+pub fn selection_statistics(state: State<AppState>) -> GlobalStatistics {
+    state.read(|e| GlobalStatistics::new(&e.statistics().global))
+}
+
+#[tauri::command(async)]
+pub fn slice_statistics(
+    state: State<AppState>,
+    start: usize,
+    end: usize,
+) -> Option<GlobalStatistics> {
+    state.read(move |e| {
+        e.statistics()
+            .slice(start, end)
+            .map(|s| GlobalStatistics::new(&s))
+    })
+}
+
+macro_rules! intervals_getters {
+    ($starts:ident, $values:ident, $field:ident) => {
+        #[tauri::command(async)]
+        pub fn $starts(state: State<AppState>) -> Bytes {
+            Bytes::new(state.read(|e| u32s(&e.statistics().$field.starts)))
+        }
+
+        #[tauri::command(async)]
+        pub fn $values(state: State<AppState>) -> Bytes {
+            Bytes::new(state.read(|e| e.statistics().$field.values.clone()))
+        }
+    };
+}
+
+intervals_getters!(surface_starts, surface_values, surface);
+intervals_getters!(highway_starts, highway_values, highway);
+intervals_getters!(sac_scale_starts, sac_scale_values, sac_scale);
+intervals_getters!(mtb_scale_starts, mtb_scale_values, mtb_scale);
+
+/// The names of the categories, in the order of their codes. The lists only grow.
+#[tauri::command(async)]
+pub fn surfaces(state: State<AppState>) -> Vec<String> {
+    state.read(|e| e.categories().surface.names().to_vec())
+}
+
+#[tauri::command(async)]
+pub fn highways(state: State<AppState>) -> Vec<String> {
+    state.read(|e| e.categories().highway.names().to_vec())
+}
+
+#[tauri::command(async)]
+pub fn sac_scales(state: State<AppState>) -> Vec<String> {
+    state.read(|e| e.categories().sac_scale.names().to_vec())
+}
+
+#[tauri::command(async)]
+pub fn mtb_scales(state: State<AppState>) -> Vec<String> {
+    state.read(|e| e.categories().mtb_scale.names().to_vec())
+}
+
+// Routing buffers
+
+#[tauri::command(async)]
+pub fn anchor_indices(state: State<AppState>) -> Bytes {
+    Bytes::new(state.read(|e| u32s(&e.routing().anchor_indices)))
+}
+
+#[tauri::command(async)]
+pub fn anchor_zooms(state: State<AppState>) -> Bytes {
+    Bytes::new(state.read(|e| e.routing().anchor_zooms.clone()))
+}
+
+#[tauri::command(async)]
+pub fn segment_starts(state: State<AppState>) -> Bytes {
+    Bytes::new(state.read(|e| u32s(&e.routing().segment_starts)))
+}
+
+#[tauri::command(async)]
+pub fn segment_ids(state: State<AppState>) -> Vec<String> {
+    state.read(|e| {
+        e.routing()
+            .segment_ids
+            .iter()
+            .map(|id| id.0.to_string())
+            .collect()
+    })
+}
+
+#[tauri::command(async)]
+pub fn routing_revision(state: State<AppState>) -> u32 {
+    state.read(|e| e.routing().revision)
+}

tauri/src/commands/storage.rs

@@ -0,0 +1,46 @@
+//! Keeping the files and the settings.
+//!
+//! For now nothing is written: the files only live as long as the app, and so do the settings.
+//! The file system storage will go here.
+
+use serde::Serialize;
+use tauri::State;
+
+use crate::dto::Outcome;
+use crate::state::AppState;
+
+/// What opening the storage found.
+#[derive(Serialize)]
+pub struct StorageOpened {
+    settings: std::collections::BTreeMap<String, String>,
+    outcome: Outcome,
+}
+
+#[tauri::command(async)]
+pub fn open_storage(state: State<AppState>) -> StorageOpened {
+    StorageOpened {
+        settings: state.settings().clone(),
+        outcome: Outcome::failed_none(),
+    }
+}
+
+/// Resolves when what was changed has been written to the storage.
+#[tauri::command(async)]
+pub fn flush_storage() {}
+
+/// Reads the files again if they were written by someone else.
+#[tauri::command(async)]
+pub fn sync_storage() -> Outcome {
+    Outcome::failed_none()
+}
+
+/// Saves a setting, `value` being its JSON.
+#[tauri::command(async)]
+pub fn set_setting(state: State<AppState>, key: String, value: String) {
+    state.settings().insert(key, value);
+}
+
+#[tauri::command(async)]
+pub fn delete_setting(state: State<AppState>, key: String) {
+    state.settings().remove(&key);
+}

tauri/src/dto.rs

@@ -0,0 +1,578 @@
+//! What crosses to the frontend, as JSON: the same shapes as the objects of the WASM interface
+//! (`gpx-rs/wasm/src/ts.rs` holds their TypeScript types).
+
+use gpx_engine::{self as engine, FileId};
+use serde::{Deserialize, Serialize};
+use uuid::Uuid;
+
+/// Bytes that cross as they are: typed arrays (little-endian), GPX files.
+pub type Bytes = tauri::ipc::Response;
+
+pub fn f64s(values: &[f64]) -> Vec<u8> {
+    values.iter().flat_map(|v| v.to_le_bytes()).collect()
+}
+
+pub fn i64s(values: &[i64]) -> Vec<u8> {
+    values.iter().flat_map(|v| v.to_le_bytes()).collect()
+}
+
+pub fn u32s(values: &[u32]) -> Vec<u8> {
+    values.iter().flat_map(|v| v.to_le_bytes()).collect()
+}
+
+/// An array that can be absent: the first byte tells whether it is there, the array follows.
+pub fn optional(array: Option<Vec<u8>>) -> Bytes {
+    let mut bytes = vec![u8::from(array.is_some())];
+    bytes.extend(array.unwrap_or_default());
+    Bytes::new(bytes)
+}
+
+pub fn ids(items: &[FileId]) -> Vec<String> {
+    items.iter().map(|id| id.0.to_string()).collect()
+}
+
+// Outcome
+
+/// What a call that edits the files or changes the selection did.
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct Outcome {
+    changed: bool,
+    order_changed: bool,
+    selection_changed: bool,
+    clipboard_changed: bool,
+    added: Vec<String>,
+    modified: Vec<String>,
+    removed: Vec<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    error: Option<String>,
+}
+
+impl Outcome {
+    pub fn new(outcome: &engine::Outcome, error: Option<String>) -> Self {
+        let diff = outcome.diff.clone().unwrap_or_default();
+        Self {
+            changed: outcome.changed,
+            order_changed: outcome.order_changed,
+            selection_changed: outcome.selection_changed,
+            clipboard_changed: outcome.clipboard_changed,
+            added: ids(&diff.added),
+            modified: ids(&diff.modified),
+            removed: ids(&diff.removed),
+            error,
+        }
+    }
+
+    /// The outcome of a call that did nothing and has nothing to say.
+    pub fn failed_none() -> Self {
+        Self::new(&engine::Outcome::default(), None)
+    }
+
+    /// What a call that does nothing returns.
+    pub fn failed(message: impl Into<String>) -> Self {
+        Self::new(&engine::Outcome::default(), Some(message.into()))
+    }
+}
+
+// Selection and clipboard
+
+#[derive(Serialize, Deserialize)]
+#[serde(
+    tag = "type",
+    rename_all = "camelCase",
+    rename_all_fields = "camelCase"
+)]
+pub enum Selection {
+    Empty,
+    File {
+        file_ids: Vec<Uuid>,
+    },
+    Track {
+        file_id: Uuid,
+        track_ids: Vec<Uuid>,
+    },
+    Segment {
+        file_id: Uuid,
+        track_id: Uuid,
+        segment_ids: Vec<Uuid>,
+    },
+    Waypoints {
+        file_id: Uuid,
+    },
+    Waypoint {
+        file_id: Uuid,
+        waypoint_ids: Vec<Uuid>,
+    },
+}
+
+impl From<&engine::Selection> for Selection {
+    fn from(selection: &engine::Selection) -> Self {
+        use engine::Selection as S;
+        match selection {
+            S::Empty => Self::Empty,
+            S::File { file_ids } => Self::File {
+                file_ids: file_ids.iter().map(|id| id.0).collect(),
+            },
+            S::Track { file_id, trk_ids } => Self::Track {
+                file_id: file_id.0,
+                track_ids: trk_ids.iter().map(|id| id.0).collect(),
+            },
+            S::TrackSegment {
+                file_id,
+                trk_id,
+                trkseg_ids,
+            } => Self::Segment {
+                file_id: file_id.0,
+                track_id: trk_id.0,
+                segment_ids: trkseg_ids.iter().map(|id| id.0).collect(),
+            },
+            S::Waypoints { file_id } => Self::Waypoints { file_id: file_id.0 },
+            S::Waypoint { file_id, wpt_ids } => Self::Waypoint {
+                file_id: file_id.0,
+                waypoint_ids: wpt_ids.iter().map(|id| id.0).collect(),
+            },
+        }
+    }
+}
+
+impl From<Selection> for engine::Selection {
+    fn from(selection: Selection) -> Self {
+        use engine::Selection as S;
+        match selection {
+            Selection::Empty => S::Empty,
+            Selection::File { file_ids } => S::File {
+                file_ids: file_ids.into_iter().map(FileId).collect(),
+            },
+            Selection::Track { file_id, track_ids } => S::Track {
+                file_id: FileId(file_id),
+                trk_ids: track_ids.into_iter().map(engine::TrackId).collect(),
+            },
+            Selection::Segment {
+                file_id,
+                track_id,
+                segment_ids,
+            } => S::TrackSegment {
+                file_id: FileId(file_id),
+                trk_id: engine::TrackId(track_id),
+                trkseg_ids: segment_ids
+                    .into_iter()
+                    .map(engine::TrackSegmentId)
+                    .collect(),
+            },
+            Selection::Waypoints { file_id } => S::Waypoints {
+                file_id: FileId(file_id),
+            },
+            Selection::Waypoint {
+                file_id,
+                waypoint_ids,
+            } => S::Waypoint {
+                file_id: FileId(file_id),
+                wpt_ids: waypoint_ids.into_iter().map(engine::WaypointId).collect(),
+            },
+        }
+    }
+}
+
+/// Where moved elements go. A negative index is the start, an infinite one the end (which JSON
+/// writes as `null`, so the frontend sends a very large number instead).
+#[derive(Deserialize)]
+#[serde(
+    tag = "type",
+    rename_all = "camelCase",
+    rename_all_fields = "camelCase"
+)]
+pub enum MoveTarget {
+    Files {
+        index: f64,
+    },
+    Tracks {
+        file_id: Uuid,
+        index: f64,
+    },
+    Segments {
+        file_id: Uuid,
+        track_id: Uuid,
+        index: f64,
+    },
+    Waypoints {
+        file_id: Uuid,
+        index: f64,
+    },
+}
+
+impl From<MoveTarget> for engine::MoveTarget {
+    fn from(target: MoveTarget) -> Self {
+        use engine::MoveTarget as T;
+        let index = |index: f64| index.max(0.0) as usize;
+        match target {
+            MoveTarget::Files { index: i } => T::Files { index: index(i) },
+            MoveTarget::Tracks { file_id, index: i } => T::Tracks {
+                file_id: FileId(file_id),
+                index: index(i),
+            },
+            MoveTarget::Segments {
+                file_id,
+                track_id,
+                index: i,
+            } => T::Segments {
+                file_id: FileId(file_id),
+                trk_id: engine::TrackId(track_id),
+                index: index(i),
+            },
+            MoveTarget::Waypoints { file_id, index: i } => T::Waypoints {
+                file_id: FileId(file_id),
+                index: index(i),
+            },
+        }
+    }
+}
+
+#[derive(Serialize)]
+pub struct Clipboard {
+    #[serde(rename = "type")]
+    kind: &'static str,
+    ids: Vec<String>,
+    cut: bool,
+}
+
+impl Clipboard {
+    pub fn new(clipboard: &engine::Clipboard) -> Self {
+        let strings = |ids: Vec<Uuid>| ids.iter().map(Uuid::to_string).collect();
+        let (kind, ids) = match clipboard.content.ids() {
+            engine::ClipboardIds::Files(ids) => {
+                ("files", strings(ids.into_iter().map(|id| id.0).collect()))
+            }
+            engine::ClipboardIds::Tracks(ids) => {
+                ("tracks", strings(ids.into_iter().map(|id| id.0).collect()))
+            }
+            engine::ClipboardIds::Segments(ids) => (
+                "segments",
+                strings(ids.into_iter().map(|id| id.0).collect()),
+            ),
+            engine::ClipboardIds::Waypoints(ids) => (
+                "waypoints",
+                strings(ids.into_iter().map(|id| id.0).collect()),
+            ),
+        };
+        Self {
+            kind,
+            ids,
+            cut: clipboard.cut,
+        }
+    }
+}
+
+// Files
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct FileStructure {
+    id: String,
+    name: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    desc: Option<String>,
+    tracks: Vec<TrackNode>,
+    waypoints: Vec<WaypointNode>,
+    waypoints_rev: String,
+}
+
+#[derive(Serialize)]
+struct TrackNode {
+    id: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    name: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    desc: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    color: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    opacity: Option<f64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    width: Option<f64>,
+    segments: Vec<SegmentNode>,
+}
+
+#[derive(Serialize)]
+struct SegmentNode {
+    id: String,
+    rev: String,
+    length: f64,
+}
+
+#[derive(Serialize)]
+struct WaypointNode {
+    id: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    name: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    sym: Option<String>,
+}
+
+impl FileStructure {
+    pub fn new(file: &engine::FileStructure) -> Self {
+        Self {
+            id: file.id.0.to_string(),
+            name: file.name.clone(),
+            desc: file.desc.clone(),
+            tracks: file
+                .tracks
+                .iter()
+                .map(|trk| TrackNode {
+                    id: trk.id.0.to_string(),
+                    name: trk.name.clone(),
+                    desc: trk.desc.clone(),
+                    color: trk.color.clone(),
+                    opacity: trk.opacity,
+                    width: trk.width,
+                    segments: trk
+                        .segments
+                        .iter()
+                        .map(|seg| SegmentNode {
+                            id: seg.id.0.to_string(),
+                            rev: seg.rev_id.0.to_string(),
+                            length: seg.len as f64,
+                        })
+                        .collect(),
+                })
+                .collect(),
+            waypoints: file
+                .waypoints
+                .iter()
+                .map(|wpt| WaypointNode {
+                    id: wpt.id.0.to_string(),
+                    name: wpt.name.clone(),
+                    sym: wpt.sym.clone(),
+                })
+                .collect(),
+            waypoints_rev: file.wpt_rev_id.0.to_string(),
+        }
+    }
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct GlobalStatistics {
+    total_distance: f64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    moving_distance: Option<f64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    total_time: Option<f64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    moving_time: Option<f64>,
+    elevation_gain: f64,
+    elevation_loss: f64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    start_time: Option<f64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    end_time: Option<f64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    total_speed: Option<f64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    moving_speed: Option<f64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    bounds: Option<Bounds>,
+}
+
+#[derive(Serialize)]
+struct Bounds {
+    west: f64,
+    south: f64,
+    east: f64,
+    north: f64,
+}
+
+impl GlobalStatistics {
+    pub fn new(stats: &engine::GlobalStatistics) -> Self {
+        let seconds = |ms: Option<i64>| ms.map(|ms| ms as f64 / 1000.0);
+        let (sw, ne) = (&stats.bounds.sw, &stats.bounds.ne);
+        Self {
+            total_distance: stats.total_distance,
+            moving_distance: stats.moving_distance,
+            total_time: seconds(stats.total_time),
+            moving_time: seconds(stats.moving_time),
+            elevation_gain: stats.elevation_gain,
+            elevation_loss: stats.elevation_loss,
+            start_time: stats.start_time.map(|t| t as f64),
+            end_time: stats.end_time.map(|t| t as f64),
+            total_speed: stats.total_speed(),
+            moving_speed: stats.moving_speed(),
+            bounds: (sw.lng <= ne.lng && sw.lat <= ne.lat).then_some(Bounds {
+                west: sw.lng,
+                south: sw.lat,
+                east: ne.lng,
+                north: ne.lat,
+            }),
+        }
+    }
+}
+
+#[derive(Serialize)]
+pub struct WaypointDetails {
+    id: String,
+    lng: f64,
+    lat: f64,
+    ele: f64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    time: Option<f64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    name: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    desc: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    cmt: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    sym: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    links: Option<Vec<Link>>,
+}
+
+#[derive(Serialize)]
+struct Link {
+    href: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    text: Option<String>,
+}
+
+impl WaypointDetails {
+    pub fn new(wpt: &engine::Waypoint) -> Self {
+        Self {
+            id: wpt.id.0.to_string(),
+            lng: wpt.coordinates.lng,
+            lat: wpt.coordinates.lat,
+            ele: wpt.ele,
+            time: wpt.time.map(|t| t as f64),
+            name: wpt.name.clone(),
+            desc: wpt.desc.clone(),
+            cmt: wpt.cmt.clone(),
+            sym: wpt.sym.clone(),
+            links: (!wpt.links.is_empty()).then(|| {
+                wpt.links
+                    .iter()
+                    .map(|link| Link {
+                        href: link.href.clone(),
+                        text: link.text.clone(),
+                    })
+                    .collect()
+            }),
+        }
+    }
+}
+
+#[derive(Serialize)]
+pub struct TrackpointDetails {
+    lng: f64,
+    lat: f64,
+    ele: f64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    time: Option<f64>,
+}
+
+impl TrackpointDetails {
+    pub fn new(pt: &engine::Trackpoint) -> Self {
+        Self {
+            lng: pt.coordinates.lng,
+            lat: pt.coordinates.lat,
+            ele: pt.ele,
+            time: pt.time.map(|t| t as f64),
+        }
+    }
+}
+
+// Enumerations
+
+#[derive(Clone, Copy, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub enum SelectMode {
+    Replace,
+    Add,
+    Toggle,
+}
+
+impl From<SelectMode> for engine::SelectMode {
+    fn from(m: SelectMode) -> Self {
+        match m {
+            SelectMode::Replace => Self::Replace,
+            SelectMode::Add => Self::Add,
+            SelectMode::Toggle => Self::Toggle,
+        }
+    }
+}
+
+#[derive(Clone, Copy, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub enum MergeType {
+    Connect,
+    Group,
+}
+
+impl From<MergeType> for engine::MergeType {
+    fn from(t: MergeType) -> Self {
+        match t {
+            MergeType::Connect => Self::Connect,
+            MergeType::Group => Self::Group,
+        }
+    }
+}
+
+#[derive(Clone, Copy, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub enum SplitType {
+    Files,
+    Tracks,
+    Segments,
+}
+
+impl From<SplitType> for engine::SplitType {
+    fn from(t: SplitType) -> Self {
+        match t {
+            SplitType::Files => Self::Files,
+            SplitType::Tracks => Self::Tracks,
+            SplitType::Segments => Self::Segments,
+        }
+    }
+}
+
+#[derive(Clone, Copy, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub enum CleanType {
+    Inside,
+    Outside,
+}
+
+impl From<CleanType> for engine::CleanType {
+    fn from(t: CleanType) -> Self {
+        match t {
+            CleanType::Inside => Self::Inside,
+            CleanType::Outside => Self::Outside,
+        }
+    }
+}
+
+// Routing
+
+/// A category of the trackpoints of a route, as in `RouteCategory` of the engine.
+#[derive(Default, Deserialize)]
+pub struct RouteCategory {
+    pub starts: Vec<u32>,
+    pub values: Vec<u8>,
+    pub names: Vec<String>,
+}
+
+impl RouteCategory {
+    pub fn view(&self) -> engine::RouteCategory<'_> {
+        engine::RouteCategory {
+            starts: &self.starts,
+            values: &self.values,
+            names: &self.names,
+        }
+    }
+}
+
+#[derive(Default, Deserialize)]
+#[serde(rename_all = "camelCase", default)]
+pub struct RouteAttributes {
+    pub surface: RouteCategory,
+    pub highway: RouteCategory,
+    pub sac_scale: RouteCategory,
+    pub mtb_scale: RouteCategory,
+}

tauri/src/lib.rs

@@ -0,0 +1,125 @@
+//! The desktop shell of gpx.studio. The engine of the files (`gpx-rs/engine`) runs in this
+//! process, and the frontend talks to it through the commands of `commands`.
+
+mod commands;
+mod dto;
+mod state;
+
+use commands::*;
+
+#[cfg_attr(mobile, tauri::mobile_entry_point)]
+pub fn run() {
+    with_engine(tauri::Builder::default())
+        .run(tauri::generate_context!())
+        .expect("error while running gpx.studio");
+}
+
+/// Gives the builder the engine and the commands that reach it.
+fn with_engine<R: tauri::Runtime>(builder: tauri::Builder<R>) -> tauri::Builder<R> {
+    builder
+        .manage(state::AppState::default())
+        .invoke_handler(tauri::generate_handler![
+            // selection
+            selection::select,
+            selection::select_all,
+            selection::arrow_select,
+            selection::select_tracks,
+            selection::select_segments,
+            selection::select_waypoint_group,
+            selection::select_waypoints,
+            // files
+            files::new_file,
+            files::load_files,
+            files::duplicate,
+            files::delete,
+            files::delete_all,
+            files::reorder,
+            files::copy,
+            files::cut,
+            files::paste,
+            files::move_elements,
+            files::undo,
+            files::redo,
+            // edits and tools
+            edit::metadata,
+            edit::style,
+            edit::new_track,
+            edit::new_track_segment,
+            edit::new_waypoint,
+            edit::move_waypoint,
+            edit::delete_waypoint,
+            edit::update_waypoint,
+            edit::reverse,
+            edit::round_trip,
+            edit::crop,
+            edit::reduce,
+            edit::change_timestamps,
+            edit::create_artificial_timestamps,
+            edit::merge,
+            edit::extract,
+            edit::elevation,
+            edit::clean,
+            routing::route,
+            routing::insert_anchor,
+            routing::change_loop_start,
+            routing::split,
+            // queries
+            queries::file_order,
+            queries::file_structure,
+            queries::file_statistics,
+            queries::selection,
+            queries::clipboard,
+            queries::can_undo,
+            queries::can_redo,
+            queries::can_paste,
+            queries::waypoint,
+            queries::trackpoint,
+            queries::export_file,
+            queries::exportable_data,
+            queries::reduction_distances,
+            queries::segment_coordinates,
+            queries::waypoint_coordinates,
+            // statistics
+            statistics::total_distance,
+            statistics::slope,
+            statistics::slope_segment_slope,
+            statistics::slope_segment_distance,
+            statistics::lng,
+            statistics::lat,
+            statistics::ele,
+            statistics::speed,
+            statistics::hr,
+            statistics::cad,
+            statistics::atemp,
+            statistics::power,
+            statistics::timestamps,
+            statistics::selection_statistics,
+            statistics::slice_statistics,
+            statistics::surface_starts,
+            statistics::surface_values,
+            statistics::highway_starts,
+            statistics::highway_values,
+            statistics::sac_scale_starts,
+            statistics::sac_scale_values,
+            statistics::mtb_scale_starts,
+            statistics::mtb_scale_values,
+            statistics::surfaces,
+            statistics::highways,
+            statistics::sac_scales,
+            statistics::mtb_scales,
+            statistics::anchor_indices,
+            statistics::anchor_zooms,
+            statistics::segment_starts,
+            statistics::segment_ids,
+            statistics::routing_revision,
+            // storage
+            storage::open_storage,
+            storage::flush_storage,
+            storage::sync_storage,
+            storage::set_setting,
+            storage::delete_setting,
+        ])
+}
+
+#[cfg(test)]
+mod tests;

tauri/src/main.rs

@@ -0,0 +1,6 @@
+// Prevents an additional console window on Windows in release.
+#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
+
+fn main() {
+    gpx_studio_desktop_lib::run()
+}

tauri/src/state.rs

@@ -0,0 +1,107 @@
+//! The state the commands share: the engine, and the settings of the frontend.
+//!
+//! The engine is not `Send` (it shares its data with `Rc`), so it lives on a thread of its own and
+//! the commands send it jobs: they are done one after the other, in the order they were sent.
+
+use std::collections::BTreeMap;
+use std::sync::mpsc::{self, Sender};
+use std::sync::{Mutex, MutexGuard};
+use std::thread;
+
+use gpx_engine::{Action, Engine};
+
+use crate::dto::Outcome;
+
+type Job = Box<dyn FnOnce(&mut Engine) + Send>;
+
+/// What the commands talk to. The engine is the same as in the browser (`gpx-rs`); here it lives in
+/// the process of the app, and the frontend reaches it through the commands only.
+pub struct AppState {
+    jobs: Mutex<Sender<Job>>,
+    /// The settings of the frontend, as JSON strings by key.
+    settings: Mutex<BTreeMap<String, String>>,
+}
+
+impl Default for AppState {
+    fn default() -> Self {
+        let (jobs, receiver) = mpsc::channel::<Job>();
+        thread::Builder::new()
+            .name("engine".into())
+            .spawn(move || {
+                let mut engine = Engine::default();
+                while let Ok(job) = receiver.recv() {
+                    job(&mut engine);
+                }
+            })
+            .expect("the engine thread could not be started");
+        Self {
+            jobs: Mutex::new(jobs),
+            settings: Mutex::default(),
+        }
+    }
+}
+
+impl AppState {
+    /// Runs `f` on the engine and waits for its result.
+    pub fn run<T: Send + 'static>(&self, f: impl FnOnce(&mut Engine) -> T + Send + 'static) -> T {
+        let (reply, result) = mpsc::channel();
+        let job: Job = Box::new(move |engine| {
+            let _ = reply.send(f(engine));
+        });
+        self.jobs
+            .lock()
+            .unwrap()
+            .send(job)
+            .expect("the engine thread stopped");
+        result.recv().expect("the engine thread stopped")
+    }
+
+    /// Reads from the engine.
+    pub fn read<T: Send + 'static>(&self, f: impl FnOnce(&Engine) -> T + Send + 'static) -> T {
+        self.run(move |engine| f(engine))
+    }
+
+    pub fn settings(&self) -> MutexGuard<'_, BTreeMap<String, String>> {
+        self.settings.lock().unwrap()
+    }
+}
+
+/// Executes an action and tells what it did, see `Outcome`.
+pub fn execute(engine: &mut Engine, action: Action) -> Outcome {
+    match engine.execute(action) {
+        Ok(outcome) => Outcome::new(&outcome, None),
+        Err(error) => Outcome::failed(error.to_string()),
+    }
+}
+
+/// Executes an action on the engine. The values the action uses are moved to the engine thread.
+macro_rules! act {
+    ($state:expr, $action:expr) => {
+        $state.run(move |engine| $crate::state::execute(engine, $action))
+    };
+}
+
+/// Executes a command (the command can borrow what it uses).
+macro_rules! edit {
+    ($state:expr, $command:expr) => {
+        act!($state, ::gpx_engine::Action::Edit($command))
+    };
+}
+
+/// Like `edit!`, but does nothing if the selection is not the one of `revision` anymore (the
+/// indices of the routing buffers only mean something for their revision).
+macro_rules! edit_at {
+    ($state:expr, $revision:expr, $command:expr) => {{
+        let revision = $revision;
+        $state.run(move |engine| {
+            if engine.routing().revision != revision {
+                return $crate::dto::Outcome::failed(
+                    "the selection changed since the routing buffers were read",
+                );
+            }
+            $crate::state::execute(engine, ::gpx_engine::Action::Edit($command))
+        })
+    }};
+}
+
+pub(crate) use {act, edit, edit_at};

tauri/src/tests.rs

@@ -0,0 +1,274 @@
+//! The commands, called the way the frontend calls them (through the IPC of Tauri), on the sample
+//! files of the engine.
+
+use serde_json::{json, Value};
+use tauri::test::{get_ipc_response, mock_builder, mock_context, noop_assets, INVOKE_KEY};
+use tauri::webview::InvokeRequest;
+use tauri::{ipc::CallbackFn, ipc::InvokeBody, ipc::InvokeResponseBody, WebviewWindow};
+
+struct App(WebviewWindow<tauri::test::MockRuntime>);
+
+impl App {
+    fn new() -> Self {
+        let app = crate::with_engine(mock_builder())
+            .build(mock_context(noop_assets()))
+            .unwrap();
+        let window = tauri::WebviewWindowBuilder::new(&app, "main", Default::default())
+            .build()
+            .unwrap();
+        // the app has to outlive its window
+        std::mem::forget(app);
+        Self(window)
+    }
+
+    fn request(
+        &self,
+        cmd: &str,
+        body: InvokeBody,
+        headers: tauri::http::HeaderMap,
+    ) -> InvokeResponseBody {
+        get_ipc_response(
+            &self.0,
+            InvokeRequest {
+                cmd: cmd.into(),
+                callback: CallbackFn(0),
+                error: CallbackFn(1),
+                url: "tauri://localhost".parse().unwrap(),
+                body,
+                headers,
+                invoke_key: INVOKE_KEY.to_string(),
+            },
+        )
+        .unwrap_or_else(|error| panic!("{cmd} failed: {error}"))
+    }
+
+    fn call(&self, cmd: &str, args: Value) -> Value {
+        match self.request(cmd, InvokeBody::Json(args), Default::default()) {
+            InvokeResponseBody::Json(json) => serde_json::from_str(&json).unwrap(),
+            InvokeResponseBody::Raw(_) => panic!("{cmd} returned bytes"),
+        }
+    }
+
+    fn bytes(&self, cmd: &str, args: Value) -> Vec<u8> {
+        match self.request(cmd, InvokeBody::Json(args), Default::default()) {
+            InvokeResponseBody::Raw(bytes) => bytes,
+            InvokeResponseBody::Json(_) => panic!("{cmd} returned JSON"),
+        }
+    }
+
+    fn load(&self, names: &[&str]) -> Value {
+        let mut data = vec![];
+        let mut lengths = vec![];
+        for name in names {
+            let file = std::fs::read(format!("../gpx-rs/engine/data/{name}.gpx")).unwrap();
+            lengths.push(file.len());
+            data.extend(file);
+        }
+        let header = |value: Value| value.to_string().replace('"', "%22").parse().unwrap();
+        let mut headers = tauri::http::HeaderMap::new();
+        headers.insert("lengths", header(json!(lengths)));
+        headers.insert("names", header(json!(names)));
+        match self.request("load_files", InvokeBody::Raw(data), headers) {
+            InvokeResponseBody::Json(json) => serde_json::from_str(&json).unwrap(),
+            InvokeResponseBody::Raw(_) => panic!("load_files returned bytes"),
+        }
+    }
+}
+
+fn f64s(bytes: &[u8]) -> Vec<f64> {
+    bytes
+        .chunks_exact(8)
+        .map(|chunk| f64::from_le_bytes(chunk.try_into().unwrap()))
+        .collect()
+}
+
+#[test]
+fn loads_files_and_describes_them() {
+    let app = App::new();
+    let outcome = app.load(&["simple", "with_tracks"]);
+    assert_eq!(outcome["changed"], true);
+    assert_eq!(outcome["added"].as_array().unwrap().len(), 2);
+    assert!(outcome.get("error").is_none());
+
+    let order = app.call("file_order", json!({}));
+    let first = order[0].as_str().unwrap();
+    assert_eq!(
+        app.call("selection", json!({})),
+        json!({ "type": "file", "fileIds": [first] })
+    );
+
+    let structure = app.call("file_structure", json!({ "fileId": first }));
+    assert_eq!(structure["name"], "simple");
+    let segment = &structure["tracks"][0]["segments"][0];
+    let length = segment["length"].as_f64().unwrap() as usize;
+    assert!(length > 0);
+
+    // coordinates are little-endian doubles, lng and lat for each trackpoint
+    let coordinates =
+        f64s(&app.bytes("segment_coordinates", json!({ "segmentId": segment["id"] })));
+    assert_eq!(coordinates.len(), 2 * length);
+
+    let statistics = app.call("file_statistics", json!({ "fileId": first }));
+    assert!(statistics["totalDistance"].as_f64().unwrap() > 0.0);
+    assert!(
+        statistics["bounds"]["west"].as_f64().unwrap()
+            <= statistics["bounds"]["east"].as_f64().unwrap()
+    );
+    assert_eq!(
+        app.call(
+            "file_structure",
+            json!({ "fileId": "00000000-0000-0000-0000-000000000000" })
+        ),
+        Value::Null
+    );
+}
+
+#[test]
+fn reads_the_statistics_of_the_selection() {
+    let app = App::new();
+    app.load(&["simple"]);
+    let distance = f64s(&app.bytes("total_distance", json!({})));
+    assert!(distance.len() > 1);
+    assert_eq!(f64s(&app.bytes("lng", json!({}))).len(), distance.len());
+    assert!(
+        app.call("selection_statistics", json!({}))["totalDistance"]
+            .as_f64()
+            .unwrap()
+            > 0.0
+    );
+    // optional arrays start with a byte telling whether they are there
+    let hr = app.bytes("hr", json!({}));
+    assert_eq!(hr[0], 0);
+    assert!(
+        app.call("slice_statistics", json!({ "start": 1, "end": 3 }))["totalDistance"].is_number()
+    );
+    assert_eq!(
+        app.call("slice_statistics", json!({ "start": 0, "end": 100000 })),
+        Value::Null
+    );
+
+    app.load(&["with_hr"]);
+    app.call("select_all", json!({}));
+    let hr = app.bytes("hr", json!({}));
+    assert_eq!(hr[0], 1);
+    assert_eq!((hr.len() - 1) % 8, 0);
+}
+
+#[test]
+fn edits_undoes_and_selects() {
+    let app = App::new();
+    let outcome = app.call(
+        "new_file",
+        json!({ "name": "route", "lng": 4.4, "lat": 50.8 }),
+    );
+    assert_eq!(outcome["changed"], true);
+    assert_eq!(app.call("can_undo", json!({})), true);
+
+    let id = app.call("file_order", json!({}))[0].clone();
+    let outcome = app.call("metadata", json!({ "name": "renamed", "desc": "" }));
+    assert_eq!(outcome["modified"], json!([id]));
+    assert_eq!(
+        app.call("file_structure", json!({ "fileId": id }))["name"],
+        "renamed"
+    );
+
+    let outcome = app.call("select", json!({ "fileIds": [], "mode": "replace" }));
+    assert_eq!(outcome["selectionChanged"], true);
+    assert_eq!(app.call("selection", json!({})), json!({ "type": "empty" }));
+    app.call("select", json!({ "fileIds": [id], "mode": "toggle" }));
+
+    app.call("undo", json!({}));
+    assert_eq!(
+        app.call("file_structure", json!({ "fileId": id }))["name"],
+        "route"
+    );
+    assert_eq!(app.call("can_redo", json!({})), true);
+    app.call("undo", json!({}));
+    assert_eq!(app.call("file_order", json!({})), json!([]));
+
+    // what cannot be done says why
+    let outcome = app.call("reverse", json!({}));
+    assert_eq!(outcome["changed"], false);
+    assert!(outcome["error"].is_string());
+}
+
+#[test]
+fn moves_and_clipboard() {
+    let app = App::new();
+    app.load(&["simple", "with_tracks"]);
+    let ids = app.call("file_order", json!({}));
+    app.call("select", json!({ "fileIds": [ids[0]], "mode": "replace" }));
+    app.call("copy", json!({}));
+    assert_eq!(
+        app.call("clipboard", json!({})),
+        json!({ "type": "files", "ids": [ids[0]], "cut": false })
+    );
+
+    let outcome = app.call(
+        "move_elements",
+        json!({
+            "what": { "type": "file", "fileIds": [ids[0]] },
+            "to": { "type": "files", "index": 9007199254740991u64 },
+        }),
+    );
+    assert_eq!(outcome["orderChanged"], true);
+    assert_eq!(app.call("file_order", json!({})), json!([ids[1], ids[0]]));
+}
+
+#[test]
+fn waypoints_exports_and_routing_revisions() {
+    let app = App::new();
+    app.call("new_file", json!({ "name": "file" }));
+    let outcome = app.call(
+        "new_waypoint",
+        json!({ "lng": 4.4, "lat": 50.8, "ele": 100, "name": "summit", "desc": "", "icon": "Summit", "link": "https://example.com" }),
+    );
+    assert_eq!(outcome["changed"], true);
+    let file = app.call("file_order", json!({}))[0].clone();
+    let waypoint =
+        app.call("file_structure", json!({ "fileId": file }))["waypoints"][0]["id"].clone();
+    let details = app.call(
+        "waypoint",
+        json!({ "fileId": file, "waypointId": waypoint }),
+    );
+    assert_eq!(details["name"], "summit");
+    assert_eq!(details["sym"], "Summit");
+    assert_eq!(details["links"][0]["href"], "https://example.com");
+
+    let exported = app.bytes(
+        "export_file",
+        json!({ "fileId": file, "time": true, "hr": true, "cad": true, "atemp": true, "power": true, "osm": true, "asRoute": false }),
+    );
+    assert_eq!(exported[0], 1);
+    assert!(String::from_utf8(exported[1..].to_vec())
+        .unwrap()
+        .contains("<wpt"));
+    assert_eq!(app.call("exportable_data", json!({ "fileIds": [file] })), 0);
+
+    let stale = app.call(
+        "route",
+        json!({
+            "revision": 12345, "start": 0, "end": 0,
+            "lng": [4.4], "lat": [50.8], "ele": [0],
+            "attributes": { "surface": { "starts": [0], "values": [0], "names": [] } },
+            "anchors": [],
+        }),
+    );
+    assert_eq!(stale["changed"], false);
+    assert!(stale["error"].as_str().unwrap().contains("routing buffers"));
+}
+
+#[test]
+fn keeps_settings_for_the_session() {
+    let app = App::new();
+    app.call(
+        "set_setting",
+        json!({ "key": "units", "value": "\"metric\"" }),
+    );
+    assert_eq!(
+        app.call("open_storage", json!({}))["settings"]["units"],
+        "\"metric\""
+    );
+    app.call("delete_setting", json!({ "key": "units" }));
+    assert_eq!(app.call("open_storage", json!({}))["settings"], json!({}));
+}