vectorcraft/crates/engine/src/cmd/views.rs

//! View → New View… / Edit Views…: saved views stored in the document; per-document view
//! toggles (Show Transparency Grid); the Character panel's Snap to Glyph options.

use serde_json::{Value, json};
use vectorcraft_doc::SavedView;
use vectorcraft_geom::Point;

use super::{CommandSpec, Result, Session, always, bad, bool_or, cmd, f64_req, finite_numbers, has_doc, str_param};

pub fn specs() -> Vec<CommandSpec> {
    vec![
        cmd!(
            "view.saved.new",
            "New View…",
            ["View"],
            None,
            "{name?, center: [x, y], zoom: (1 = 100%), rotation?: deg} save a view in the document (the app fills in the current one; default \"View N\"; at most 25, names up to 255 characters, each name once) → {name, index}",
            has_doc,
            new_view
        ),
        cmd!(
            "view.saved.edit",
            "Edit Views…",
            ["View"],
            None,
            "{name, newName?: rename, delete?: bool} | {edits: [{name, newName?, delete?}…]} rename or delete saved views, all in one undo step; names are those before the edit and must stay unique; no params → {views}",
            has_views,
            edit_views
        ),
        cmd!(query "view.saved.list", "Saved Views", [], None, "{} → {views: [{name, center, zoom, rotation}]}", has_doc, list_views),
        cmd!(
            query "view.transparencyGrid",
            "Show Transparency Grid",
            ["View"],
            Some("Cmd+Shift+D"),
            "{on?: bool (default: toggle)} show the transparency grid behind the active document's artboards (each document has its own setting) → {on}",
            has_doc,
            transparency_grid
        ),
        cmd!(
            query "view.snapToGlyph.options",
            "Snap to Glyph Options",
            [],
            None,
            "{baseline?: bool, xHeight?: bool, bounds?: bool, proximity?: bool, angular?: bool, anchors?: bool} the Character panel's Snap to Glyph options, kept in the preferences (the glyphSnap group, all on by default): which guides View › Snap to Glyph gives — the baseline and x-height of a single line of type, Glyph Bounds (each glyph's edges), Proximity Guides (both edges of each character's width), Angular Guides (a glyph's slanted strokes, and every guide of rotated type) and the glyphs' anchor points; {} reads them → the options",
            always,
            glyph_snap_options
        ),
    ]
}

fn glyph_snap_options(s: &mut Session, p: &Value) -> Result<Value> {
    s.prefs.glyph_snap = s.prefs.glyph_snap.merged(p).map_err(|e| bad("view.snapToGlyph.options", e))?;
    Ok(json!(s.prefs.glyph_snap))
}

fn transparency_grid(s: &mut Session, p: &Value) -> Result<Value> {
    let st = s.doc_mut()?;
    st.transparency_grid = p.get("on").and_then(Value::as_bool).unwrap_or(!st.transparency_grid);
    Ok(json!({ "on": st.transparency_grid }))
}

fn list_views(s: &mut Session, _: &Value) -> Result<Value> {
    Ok(json!({ "views": s.doc()?.doc.views }))
}

fn new_view(s: &mut Session, p: &Value) -> Result<Value> {
    const C: &str = "view.saved.new";
    let [x, y] = p.get("center").and_then(finite_numbers::<2>).ok_or_else(|| bad(C, "center must be [x, y]"))?;
    let zoom = f64_req(p, "zoom", C)?;
    if !(zoom.is_finite() && zoom > 0.0) {
        return Err(bad(C, "zoom must be positive"));
    }
    // Given, the rotation is a number: nothing malformed falls back to 0°.
    let rotation = match p.get("rotation") {
        Some(r) => r.as_f64().filter(|r| r.is_finite()).ok_or_else(|| bad(C, "rotation must be a number of degrees"))?,
        None => 0.0,
    };
    let st = s.doc()?;
    if st.doc.views.len() >= SavedView::MAX {
        return Err(bad(C, format!("a document keeps at most {} views", SavedView::MAX)));
    }
    let name = match str_param(p, "name").and_then(SavedView::clean_name) {
        Some(n) => n,
        None => SavedView::default_name(&st.doc.views),
    };
    if st.doc.views.iter().any(|v| v.name == name) {
        return Err(bad(C, format!("a view named `{name}` exists")));
    }
    let view = SavedView { name: name.clone(), center: Point::new(x, y), zoom, rotation };
    let index = s.edit("New View", |d, _| {
        d.views.push(view);
        Ok(d.views.len() - 1)
    })?;
    Ok(json!({ "name": name, "index": index }))
}

/// Edit Views… needs a document with at least one saved view.
fn has_views(s: &Session) -> std::result::Result<(), String> {
    let st = s.active().ok_or("no document open")?;
    if st.doc.views.is_empty() { Err("no saved views".into()) } else { Ok(()) }
}

fn edit_views(s: &mut Session, p: &Value) -> Result<Value> {
    const C: &str = "view.saved.edit";
    let (edits, one) = match p.get("edits").and_then(Value::as_array) {
        Some(list) => (list.as_slice(), false),
        None if str_param(p, "name").is_some() => (std::slice::from_ref(p), true),
        None => return list_views(s, p),
    };
    let before = s.doc()?.doc.views.clone();
    // Edits name the views as they are now, so they don't depend on each other's order.
    let mut after: Vec<Option<SavedView>> = before.iter().cloned().map(Some).collect();
    for e in edits {
        let name = str_param(e, "name").ok_or_else(|| bad(C, "missing name"))?;
        let i = before.iter().position(|v| v.name == name).ok_or_else(|| bad(C, format!("no view named `{name}`")))?;
        let Some(slot) = after.get_mut(i) else { continue };
        if bool_or(e, "delete", false) {
            *slot = None;
        } else if let Some(v) = slot {
            v.name = str_param(e, "newName").and_then(SavedView::clean_name).ok_or_else(|| bad(C, "give newName or delete"))?;
        }
    }
    let after: Vec<SavedView> = after.into_iter().flatten().collect();
    let mut names = std::collections::HashSet::with_capacity(after.len());
    for v in &after {
        if !names.insert(v.name.as_str()) {
            return Err(bad(C, format!("a view named `{}` exists", v.name)));
        }
    }
    // One rename or delete keeps the name of its step; several are one Edit Views step.
    let deleted = after.len() < before.len();
    let label = if !one {
        "Edit Views"
    } else if deleted {
        "Delete View"
    } else {
        "Rename View"
    };
    let result = match (one, deleted) {
        (true, true) => json!({ "deleted": str_param(p, "name") }),
        (true, false) => json!({ "name": str_param(p, "newName").and_then(SavedView::clean_name) }),
        (false, _) => json!({ "views": after }),
    };
    if before != after {
        s.edit(label, |d, _| {
            d.views = after;
            Ok(())
        })?;
    }
    Ok(result)
}

#[cfg(test)]
mod tests {
    use serde_json::json;

    use crate::Session;

    /// Malformed dimensions are rejected rather than saving an arbitrary or partial viewport.
    #[test]
    fn saved_views_require_exact_finite_coordinates_and_rotation() {
        let mut s = Session::new();
        s.execute("file.new", &json!({})).unwrap();
        let before = s.doc().unwrap().history.undo.len();
        for params in [
            json!({"center": [10], "zoom": 2}),
            json!({"center": [10, 20, 30], "zoom": 2}),
            json!({"center": [10, "bad"], "zoom": 2}),
            json!({"center": [10, 20], "zoom": 2, "rotation": "bad"}),
            json!({"center": [10, 20], "zoom": 2, "rotation": null}),
        ] {
            assert!(s.execute("view.saved.new", &params).is_err(), "accepted {params}");
            assert!(s.doc().unwrap().doc.views.is_empty());
            assert_eq!(s.doc().unwrap().history.undo.len(), before);
        }
        s.execute("view.saved.new", &json!({"center": [10, 20], "zoom": 2, "rotation": -15})).unwrap();
        let views = &s.doc().unwrap().doc.views;
        assert_eq!(views.len(), 1);
        assert_eq!(views[0].rotation, -15.0);
    }

    #[test]
    fn save_rename_delete_views() {
        let mut s = Session::new();
        s.execute("file.new", &json!({})).unwrap();
        let v = s.execute("view.saved.new", &json!({"center": [100, 200], "zoom": 2.0})).unwrap();
        assert_eq!(v["name"], json!("View 1"));
        s.execute("view.saved.new", &json!({"name": "Logo", "center": [10, 20], "zoom": 4.0, "rotation": 15})).unwrap();
        assert!(s.execute("view.saved.new", &json!({"name": "Logo", "center": [0, 0], "zoom": 1.0})).is_err());
        assert!(s.execute("view.saved.new", &json!({"center": [0, 0], "zoom": 0})).is_err());
        s.execute("view.saved.edit", &json!({"name": "View 1", "newName": "Overview"})).unwrap();
        let l = s.execute("view.saved.list", &json!({})).unwrap();
        assert_eq!(l["views"][0]["name"], json!("Overview"));
        assert_eq!(l["views"][1]["rotation"], json!(15.0));
        s.execute("view.saved.edit", &json!({"name": "Logo", "delete": true})).unwrap();
        assert_eq!(s.doc().unwrap().doc.views.len(), 1);
        // Views travel with the file.
        let bytes = vectorcraft_format::save_file(&s.doc().unwrap().doc);
        assert_eq!(vectorcraft_format::load(&bytes).unwrap().views[0].name, "Overview");
    }

    fn names(s: &mut Session) -> Vec<String> {
        s.doc().unwrap().doc.views.iter().map(|v| v.name.clone()).collect()
    }

    fn session_with_views(names: &[&str]) -> Session {
        let mut s = Session::new();
        s.execute("file.new", &json!({})).unwrap();
        for (i, n) in names.iter().enumerate() {
            s.execute("view.saved.new", &json!({"name": n, "center": [i, i], "zoom": 1 + i})).unwrap();
        }
        s
    }

    /// Two named views go out with the file and come back with their names, centres, zooms and
    /// rotations, in order.
    #[test]
    fn saved_views_reopen_with_their_names_and_viewports() {
        let mut s = Session::new();
        s.execute("file.new", &json!({})).unwrap();
        s.execute("view.saved.new", &json!({"name": "Overview", "center": [306, 396], "zoom": 0.5})).unwrap();
        s.execute("view.saved.new", &json!({"name": "Logo detail", "center": [40.25, -12.5], "zoom": 8, "rotation": -30})).unwrap();
        let saved = s.doc().unwrap().doc.views.clone();
        let back = vectorcraft_format::load(&vectorcraft_format::save_file(&s.doc().unwrap().doc)).unwrap();
        assert_eq!(back.views, saved);
        assert_eq!((back.views[1].center.x, back.views[1].center.y, back.views[1].zoom, back.views[1].rotation), (40.25, -12.5, 8.0, -30.0));
    }

    /// Edit Views… applies its renames and deletes together, as one undo step, by the names the
    /// views had before (so two can swap names); a shared or unknown name changes nothing.
    #[test]
    fn edit_views_applies_several_edits_as_one_step() {
        let mut s = session_with_views(&["A", "B", "C"]);
        let steps = s.doc().unwrap().history.undo.len();
        let edits = json!({"edits": [
            {"name": "A", "newName": "B"},
            {"name": "B", "newName": " A "},
            {"name": "C", "delete": true},
        ]});
        let r = s.execute("view.saved.edit", &edits).unwrap();
        assert_eq!(r["views"].as_array().map(Vec::len), Some(2));
        assert_eq!(names(&mut s), ["B", "A"]);
        // The views keep their viewports under their new names.
        assert_eq!(s.doc().unwrap().doc.views[0].zoom, 1.0);
        assert_eq!(s.doc().unwrap().history.undo.len(), steps + 1);
        s.execute("edit.undo", &json!({})).unwrap();
        assert_eq!(names(&mut s), ["A", "B", "C"]);
        for bad in [
            json!({"edits": [{"name": "A", "newName": "C"}]}),
            json!({"edits": [{"name": "A", "newName": "X"}, {"name": "B", "newName": "X"}]}),
            json!({"edits": [{"name": "A", "delete": true}, {"name": "Nope", "delete": true}]}),
            json!({"edits": [{"name": "A", "newName": "  "}]}),
        ] {
            assert!(s.execute("view.saved.edit", &bad).is_err(), "accepted {bad}");
            assert_eq!(names(&mut s), ["A", "B", "C"]);
        }
    }

    /// A document keeps at most 25 views; unnamed ones take the first free "View N", and names are
    /// capped like other names the user gives.
    #[test]
    fn a_document_keeps_at_most_25_views() {
        let all: Vec<String> = (0..25).map(|i| format!("V{i}")).collect();
        let mut s = session_with_views(&all.iter().map(String::as_str).collect::<Vec<_>>());
        assert!(s.execute("view.saved.new", &json!({"name": "One too many", "center": [0, 0], "zoom": 1})).is_err());
        assert_eq!(s.doc().unwrap().doc.views.len(), 25);
        s.execute("view.saved.edit", &json!({"name": "V0", "delete": true})).unwrap();
        assert_eq!(s.execute("view.saved.new", &json!({"center": [0, 0], "zoom": 1})).unwrap()["name"], "View 1");
        s.execute("view.saved.edit", &json!({"name": "V1", "delete": true})).unwrap();
        let long = "x".repeat(1000);
        assert_eq!(s.execute("view.saved.new", &json!({"name": long, "center": [0, 0], "zoom": 1})).unwrap()["name"], "x".repeat(255));
    }

    /// Edit Views… is off until the document has a view.
    #[test]
    fn edit_views_needs_a_saved_view() {
        let mut s = session_with_views(&[]);
        assert!(s.execute("view.saved.edit", &json!({})).is_err());
        s.execute("view.saved.new", &json!({"name": "Only", "center": [0, 0], "zoom": 1})).unwrap();
        assert_eq!(s.execute("view.saved.edit", &json!({})).unwrap()["views"][0]["name"], "Only");
    }
}