BREP_app 0.1.0

//! Info windows — MULTIPLE **pinned per-entity** inspector windows (the engine-
//! native successor to the single Properties window). Each is a floating (movable
//! + resizable [`egui::Window`], drawn at ctx level like the file dialog) window
//! that inspects ONE fixed object — a solid / face / edge name — split across the
//! same two tabs the old Properties window used:
//!
//! * **Tab 1 — Metadata (editable):** the name-keyed attribute editor. Each row
//!   is `key + editable value + ×`, plus an "add attribute" row. Edits go straight
//!   to the engine store via [`EngineState::set_metadata_attribute`] /
//!   [`EngineState::remove_metadata_attribute`]; they persist WITH the model. The
//!   well-known `density` attribute drives a solid's weight.
//! * **Tab 2 — Info (READ-ONLY):** the resolved measurements + provenance from
//!   [`EngineState::object_info_json`] — never editable.
//!
//! **Pinning.** The KEY difference from the old Properties window: a window's
//! `target` name is FIXED when it is opened (from the [`crate::panels::context_bar`]
//! Info action) and is NEVER reassigned from the live selection. All engine data is
//! fetched BY THAT NAME (`object_info_json(target)` / `object_metadata_json(target)`),
//! so a window keeps showing its entity's data forever, regardless of what the user
//! selects afterwards. Selecting another object opens a NEW window (or focuses an
//! existing one) — it never re-targets an open one.
//!
//! [`InfoWindows`] is the manager the shell owns: a `Vec` of pinned windows, drawn
//! every frame and pruned when the user closes one (its `×`). `open_for` opens one
//! window per selected name with a DEDUP rule (already-open name → keep it, don't
//! duplicate). Each window owns its OWN edit buffers so multiple windows never
//! share state. `EngineState` (brep-render) stays the single brain, borrowed in.
//! All lengths are millimetres (the kernel convention).

use brep_render::engine_state::EngineState;
use eframe::egui;
use serde_json::Value;
use std::collections::{BTreeMap, HashMap};

/// The two tabs of an Info window.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
enum Tab {
    /// The editable name-keyed attribute editor.
    Metadata,
    /// The read-only measurements + provenance.
    Info,
}

/// ONE pinned per-entity inspector window. Its `target` is fixed at open time and
/// drives every engine query — later selection changes CANNOT retarget it (that is
/// the whole point). Owns its own tab + edit buffers so windows never share state.
struct PinnedInfoWindow {
    /// The object name this window is PINNED to (a solid / face / edge). Fixed at
    /// construction; never reassigned. Also the window title.
    target: String,
    /// Whether the window is still shown. Its own `×` clears this; the manager then
    /// prunes it. Never re-opened — a closed window is dropped, a re-request makes a
    /// fresh one.
    open: bool,
    /// The active tab.
    tab: Tab,
    /// Whether the metadata edit buffers have been seeded from the store yet. Seeded
    /// LAZILY on the first `show` (not at construction) so `open_for` stays engine-
    /// free and the manager is unit-testable without an `EngineState`.
    seeded: bool,
    /// Live edit buffers for the target's existing attributes (`key → value`),
    /// seeded from the engine store once, then kept in lock-step as the user types.
    values: BTreeMap<String, String>,
    /// The "add attribute" row buffers (attribute name + value).
    new_key: String,
    new_value: String,
    /// The window's default open position (cascaded per open-order so a multi-select
    /// open doesn't stack every window on the exact same spot).
    default_pos: [f32; 2],
    /// Per-frame interactive-widget screen rects (egui points), keyed with this
    /// window's target so the manager can publish them un-ambiguously for the headed
    /// verifier.
    hits: HashMap<String, egui::Rect>,
}

impl PinnedInfoWindow {
    fn new(target: impl Into<String>, default_pos: [f32; 2]) -> Self {
        Self {
            target: target.into(),
            open: true,
            tab: Tab::Info,
            seeded: false,
            values: BTreeMap::new(),
            new_key: String::new(),
            new_value: String::new(),
            default_pos,
            hits: HashMap::new(),
        }
    }

    /// Seed the metadata edit buffers from the store the first time we draw. Keeping
    /// this out of the constructor is what lets `open_for` run without an engine.
    fn ensure_seeded(&mut self, state: &EngineState) {
        if self.seeded {
            return;
        }
        self.seeded = true;
        if let Some(record) = parse(&state.object_metadata_json(&self.target)).as_object() {
            for (key, value) in record {
                self.values
                    .insert(key.clone(), value.as_str().unwrap_or("").to_string());
            }
        }
    }

    /// Draw the window (if open) at ctx level. Folds the window's own close (`×`)
    /// back into `self.open` so the manager can prune it.
    fn show(&mut self, ctx: &egui::Context, state: &mut EngineState) {
        self.hits.clear();
        if !self.open {
            return;
        }
        self.ensure_seeded(state);
        // `egui::Window::open` needs its own `&mut bool`; borrow a copy so the draw
        // closure can still take `&mut self`, then fold the close back in. The title
        // is the entity name; the manager's dedup guarantees it is unique, so the
        // derived egui window id never collides.
        let mut open = true;
        egui::Window::new(&self.target)
            .id(egui::Id::new(("brep-info-window", self.target.as_str())))
            .open(&mut open)
            .movable(true)
            .resizable(true)
            // Bounded default size + a fill ScrollArea (below) so the window is
            // FREELY resizable LARGER than its content (egui otherwise hugs the
            // window to content and refuses to grow).
            .default_size([300.0, 360.0])
            .default_pos(self.default_pos)
            .show(ctx, |ui| {
                egui::ScrollArea::vertical()
                    .auto_shrink([false, false])
                    .show(ui, |ui| self.body(ui, state));
            });
        self.open = open;
    }

    /// The window body: the tab strip, then the active tab. There is always a
    /// target (the window is opened FOR one), so no "select an object" hint.
    fn body(&mut self, ui: &mut egui::Ui, state: &mut EngineState) {
        ui.horizontal(|ui| {
            let meta = ui.selectable_value(&mut self.tab, Tab::Metadata, "Metadata");
            let info = ui.selectable_value(&mut self.tab, Tab::Info, "Info");
            self.hits
                .insert(format!("{}:tab:metadata", self.target), meta.rect);
            self.hits.insert(format!("{}:tab:info", self.target), info.rect);
        });
        ui.separator();

        let name = self.target.clone();
        match self.tab {
            Tab::Metadata => self.metadata_tab(ui, state, &name),
            Tab::Info => info_tab(ui, state, &name),
        }
    }

    /// Tab 1 — the editable, name-keyed attribute editor. Each existing attribute is
    /// `key + editable value + ×`; the add row appends a new attribute. Every
    /// mutation writes straight through to the engine store (which persists with the
    /// model), keeping the local buffers in lock-step.
    fn metadata_tab(&mut self, ui: &mut egui::Ui, state: &mut EngineState, name: &str) {
        ui.label("Attributes (name-keyed; survive edits, rollback and re-tessellation):");
        ui.add_space(2.0);

        let keys: Vec<String> = self.values.keys().cloned().collect();
        let mut remove: Option<String> = None;
        egui::Grid::new(("info-metadata-grid", name))
            .num_columns(3)
            .striped(true)
            .show(ui, |ui| {
                for key in &keys {
                    ui.label(key);
                    if let Some(value) = self.values.get_mut(key) {
                        let edit =
                            ui.add(egui::TextEdit::singleline(value).desired_width(140.0));
                        if edit.changed() {
                            state.set_metadata_attribute(name, key, value);
                        }
                        self.hits.insert(format!("{name}:value:{key}"), edit.rect);
                    }
                    let del = ui.button("\u{00d7}").on_hover_text("Remove attribute");
                    self.hits.insert(format!("{name}:remove:{key}"), del.rect);
                    if del.clicked() {
                        remove = Some(key.clone());
                    }
                    ui.end_row();
                }
            });
        if let Some(key) = remove {
            state.remove_metadata_attribute(name, &key);
            self.values.remove(&key);
        }

        if keys.is_empty() {
            ui.weak("(no attributes yet)");
        }

        ui.add_space(6.0);
        ui.separator();
        ui.label("Add attribute:");
        ui.horizontal(|ui| {
            let key = ui.add(
                egui::TextEdit::singleline(&mut self.new_key)
                    .hint_text("name")
                    .desired_width(110.0),
            );
            let val = ui.add(
                egui::TextEdit::singleline(&mut self.new_value)
                    .hint_text("value")
                    .desired_width(140.0),
            );
            let add = ui.button("Add");
            self.hits.insert(format!("{name}:new:key"), key.rect);
            self.hits.insert(format!("{name}:new:value"), val.rect);
            self.hits.insert(format!("{name}:new:add"), add.rect);
            let commit = add.clicked()
                || (val.lost_focus() && ui.input(|i| i.key_pressed(egui::Key::Enter)));
            let trimmed = self.new_key.trim().to_string();
            if commit && !trimmed.is_empty() {
                state.set_metadata_attribute(name, &trimmed, &self.new_value);
                self.values.insert(trimmed, self.new_value.clone());
                self.new_key.clear();
                self.new_value.clear();
            }
        });

        ui.add_space(6.0);
        ui.weak("Hint: the well-known `density` attribute (mass per mm\u{00b3}) drives a solid's weight.");
    }
}

/// The shell-owned manager of the pinned Info windows: opens them (from the context
/// bar's Info action), draws them each frame, and prunes the ones the user closes.
#[derive(Default)]
pub struct InfoWindows {
    /// The open windows, in open order. Independent state per window.
    windows: Vec<PinnedInfoWindow>,
    /// Monotonic count of windows ever opened this session — used only to cascade
    /// each new window's default position so multi-select opens don't stack exactly.
    opened_count: usize,
}

impl InfoWindows {
    pub fn new() -> Self {
        Self::default()
    }

    /// Open one pinned window per name (a viewport multi-select yields N names → N
    /// windows). DEDUP: if a window is already open for a name, keep it — don't
    /// duplicate. Empty names are skipped. Engine-free (buffers seed lazily on the
    /// first draw) so it needs no `EngineState`.
    pub fn open_for(&mut self, names: &[String]) {
        for name in names {
            if name.is_empty() {
                continue;
            }
            // Already showing this exact entity → keep the existing window.
            if self.windows.iter().any(|w| w.open && w.target == *name) {
                continue;
            }
            // Cascade the default position off the open-order so a multi-select open
            // fans the windows out instead of stacking them on one spot.
            let k = (self.opened_count % 8) as f32;
            self.opened_count += 1;
            let pos = [1040.0 - 24.0 * k, 56.0 + 24.0 * k];
            self.windows.push(PinnedInfoWindow::new(name.clone(), pos));
        }
    }

    /// Draw every open window at ctx level (like the file dialog / settings window),
    /// then drop the ones the user closed. Independent windows → independent state.
    pub fn show(&mut self, ctx: &egui::Context, state: &mut EngineState) {
        for w in &mut self.windows {
            w.show(ctx, state);
        }
        self.prune();
    }

    /// Drop windows the user closed via their `×`. Called by `show` after drawing;
    /// exposed for the manager unit tests.
    fn prune(&mut self) {
        self.windows.retain(|w| w.open);
    }

    /// The FIXED target names of the currently-open windows, in open order — the
    /// unit-test seam proving pin-independence, dedup and prune with NO engine.
    #[cfg_attr(target_arch = "wasm32", allow(dead_code))]
    pub fn targets(&self) -> Vec<String> {
        self.windows
            .iter()
            .filter(|w| w.open)
            .map(|w| w.target.clone())
            .collect()
    }

    /// Composite state of every open window for the headed verifier — each record is
    /// `{ target, tab, metadata{…}, info{…} }`, all keyed by the window's FIXED
    /// target so the verifier can assert a window keeps its entity across selection
    /// changes. (wasm only; present-but-dead on native so `tab`/`target` count as
    /// read there too.)
    #[cfg_attr(not(target_arch = "wasm32"), allow(dead_code))]
    pub fn published_json(&self, state: &mut EngineState) -> String {
        let windows: Vec<Value> = self
            .windows
            .iter()
            .filter(|w| w.open)
            .map(|w| {
                serde_json::json!({
                    "target": w.target,
                    "tab": match w.tab { Tab::Metadata => "metadata", Tab::Info => "info" },
                    "metadata": parse(&state.object_metadata_json(&w.target)),
                    "info": parse(&state.object_info_json(&w.target)),
                })
            })
            .collect();
        serde_json::json!({ "count": windows.len(), "windows": windows }).to_string()
    }

    /// The union of every open window's per-frame interactive-widget screen rects
    /// (egui points) as `{ key: [x, y, w, h] }`, each key prefixed with the window's
    /// target (`<name>:tab:info`, `<name>:value:<k>`, `<name>:new:add`, …).
    #[cfg_attr(not(target_arch = "wasm32"), allow(dead_code))]
    pub fn hits_json(&self) -> String {
        let mut map = serde_json::Map::new();
        for w in &self.windows {
            for (key, rect) in &w.hits {
                map.insert(
                    key.clone(),
                    serde_json::json!([rect.min.x, rect.min.y, rect.width(), rect.height()]),
                );
            }
        }
        Value::Object(map).to_string()
    }
}

/// Tab 2 — the READ-ONLY info: name / creating feature, then the kind-specific
/// measurements. NOTHING here is editable.
fn info_tab(ui: &mut egui::Ui, state: &mut EngineState, name: &str) {
    let info = parse(&state.object_info_json(name));
    if info.get("ok").and_then(Value::as_bool) != Some(true) {
        ui.label(
            info.get("message")
                .and_then(Value::as_str)
                .unwrap_or("no info for this object"),
        );
        return;
    }
    let kind = info.get("kind").and_then(Value::as_str).unwrap_or("");

    egui::Grid::new(("info-info-grid", name))
        .num_columns(2)
        .striped(true)
        .show(ui, |ui| {
            grid_row(ui, "Name / ID", name.to_string());
            grid_row(ui, "Kind", kind.to_string());
            grid_row(ui, "Creating feature", creating_feature_str(&info));
            match kind {
                "solid" => {
                    grid_row(ui, "Volume (mm\u{00b3})", num(getf(&info, "volume")));
                    grid_row(ui, "Surface area (mm\u{00b2})", num(getf(&info, "surfaceArea")));
                    grid_row(ui, "Edge length total (mm)", num(getf(&info, "edgeLengthTotal")));
                    grid_row(ui, "Density (mass/mm\u{00b3})", num(getf(&info, "density")));
                    grid_row(ui, "Weight (mass)", num(getf(&info, "weight")));
                }
                "face" => {
                    grid_row(ui, "Solid", getstr(&info, "solid"));
                    grid_row(ui, "Area (mm\u{00b2})", num(getf(&info, "area")));
                    grid_row(ui, "Edge length total (mm)", num(getf(&info, "edgeLengthTotal")));
                }
                "edge" => {
                    grid_row(ui, "Solid", getstr(&info, "solid"));
                    grid_row(ui, "Length (mm)", num(getf(&info, "length")));
                }
                _ => {}
            }
        });

    ui.add_space(6.0);
    ui.weak("Read-only. Set `density` on the Metadata tab to drive a solid's weight.");
}

/// The `creatingFeature` provenance as `id (type)`, or `—` when the object has no
/// known producer (a `null` provenance).
fn creating_feature_str(info: &Value) -> String {
    match info.get("creatingFeature") {
        Some(Value::Object(feature)) => {
            let id = feature.get("id").and_then(Value::as_str).unwrap_or("");
            let kind = feature.get("type").and_then(Value::as_str).unwrap_or("");
            if kind.is_empty() {
                id.to_string()
            } else {
                format!("{id} ({kind})")
            }
        }
        _ => "\u{2014}".to_string(),
    }
}

/// Parse an engine JSON string, defaulting to `null` on any error.
fn parse(json: &str) -> Value {
    serde_json::from_str(json).unwrap_or(Value::Null)
}

/// `label: value` row inside an `egui::Grid`.
fn grid_row(ui: &mut egui::Ui, label: &str, value: String) {
    ui.label(label);
    ui.label(value);
    ui.end_row();
}

/// A JSON number field (`0` for a missing / null field).
fn getf(value: &Value, key: &str) -> f64 {
    value.get(key).and_then(Value::as_f64).unwrap_or(0.0)
}

/// A JSON string field (empty for a missing / null field).
fn getstr(value: &Value, key: &str) -> String {
    value.get(key).and_then(Value::as_str).unwrap_or("").to_string()
}

/// Format a number readably (fixed 3 decimals, trailing-zero trimmed); `0` stays
/// `0`.
fn num(x: f64) -> String {
    if x == 0.0 {
        return "0".to_string();
    }
    let mut s = format!("{x:.3}");
    if s.contains('.') {
        while s.ends_with('0') {
            s.pop();
        }
        if s.ends_with('.') {
            s.pop();
        }
    }
    s
}

#[cfg(test)]
mod tests {
    use super::*;

    fn names(list: &[&str]) -> Vec<String> {
        list.iter().map(|s| s.to_string()).collect()
    }

    #[test]
    fn open_for_creates_one_window_per_name() {
        // A multi-select viewport pick (3 names) → 3 independent windows.
        let mut m = InfoWindows::new();
        m.open_for(&names(&["A", "B", "C"]));
        assert_eq!(m.targets(), names(&["A", "B", "C"]));
    }

    #[test]
    fn dedup_keeps_existing_window_for_same_name() {
        // Clicking Info again while the SAME entity is selected must not duplicate.
        let mut m = InfoWindows::new();
        m.open_for(&names(&["A"]));
        m.open_for(&names(&["A"]));
        assert_eq!(m.targets(), names(&["A"]));
    }

    #[test]
    fn later_open_does_not_retarget_earlier_window() {
        // PIN-INDEPENDENCE: opening a window for B (i.e. the user selected B and hit
        // Info) leaves A's window untouched — a window is pinned to its open-time
        // name and no later action retargets it.
        let mut m = InfoWindows::new();
        m.open_for(&names(&["A"]));
        m.open_for(&names(&["B"]));
        assert_eq!(m.targets(), names(&["A", "B"]));
        assert_eq!(m.windows[0].target, "A");
        assert_eq!(m.windows[1].target, "B");
    }

    #[test]
    fn empty_names_are_ignored() {
        let mut m = InfoWindows::new();
        m.open_for(&names(&["", "A", ""]));
        assert_eq!(m.targets(), names(&["A"]));
    }

    #[test]
    fn prune_drops_closed_windows() {
        // The window's `×` clears its `open`; the manager then drops it.
        let mut m = InfoWindows::new();
        m.open_for(&names(&["A", "B"]));
        m.windows[0].open = false;
        m.prune();
        assert_eq!(m.targets(), names(&["B"]));
        assert_eq!(m.windows.len(), 1);
    }

    #[test]
    fn reopen_after_close_creates_a_fresh_window() {
        // Once closed + pruned, re-requesting the same name makes a NEW window.
        let mut m = InfoWindows::new();
        m.open_for(&names(&["A"]));
        m.windows[0].open = false;
        m.prune();
        m.open_for(&names(&["A"]));
        assert_eq!(m.targets(), names(&["A"]));
    }
}