open-gpui-canvas 0.2.0

use super::model::{
    CanvasPaintInteractionState, CanvasPaintModel, CanvasPaintOptions, CanvasPaintTheme,
};
use super::style::{parse_color, positive_pixels};
use crate::tool::RECONNECT_HANDLE_VIEW_SIZE;
use crate::{
    CanvasConnectionEndpointRole, CanvasDefaultEdgeRouter, CanvasEdge, CanvasEdgeRoute,
    CanvasEdgeRouteKind, CanvasEdgeRouter, CanvasEndpoint, CanvasGeometryFacts, CanvasKindLabel,
    CanvasRecordId, CanvasRecordScopeOptions, CanvasResolvedSelectionScope, CanvasRoutePath,
    CanvasRouteRequest, CanvasRouteSegment, CanvasSelection, CanvasSnapAxis, CanvasSnapGuide,
    CanvasTransformHandle, CanvasTransformTarget, CanvasViewport, EdgeId, HitOptions, HitTarget,
    canvas_transform_handles, connection_hit_options, resolve_selection_scope,
};
use open_gpui::{
    Bounds, Hsla, Pixels, Point, SharedString, TextRun, Window, WrappedLine, px, size,
};

const CONNECTION_TARGET_FEEDBACK_VIEW_SIZE: Pixels = px(18.0);
const RECONNECT_HANDLE_VISUAL_SIZE: Pixels = px(11.0);

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintFrame {
    pub visible_document_bounds: Bounds<Pixels>,
    pub records: Vec<CanvasPaintRecord>,
    pub interaction: CanvasPaintInteractionFrame,
}

impl CanvasPaintFrame {
    pub fn widget_overlay_frame(
        &self,
        options: CanvasWidgetOverlayOptions,
    ) -> CanvasWidgetOverlayFrame {
        collect_widget_overlay_frame(self, options)
    }

    pub fn scene_frame(&self) -> CanvasSceneFrame {
        CanvasSceneFrame::from_paint_frame(self)
    }
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasSceneFrame {
    pub visible_document_bounds: Bounds<Pixels>,
    record_groups: Vec<CanvasSceneRecordGroup>,
    edge_items: Vec<CanvasSceneLayerItem>,
    tool_chrome: CanvasPaintInteractionFrame,
}

impl CanvasSceneFrame {
    pub fn from_paint_frame(frame: &CanvasPaintFrame) -> Self {
        let mut record_groups = Vec::new();
        let mut edge_items = Vec::new();

        for (ordinal, record) in frame.records.iter().enumerate() {
            match record.target {
                HitTarget::Edge(_) => edge_items.push(CanvasSceneLayerItem::from_record(
                    record,
                    ordinal,
                    CanvasSceneLayerPhase::EdgeBehindNodes,
                )),
                _ => record_groups.push(CanvasSceneRecordGroup::from_record(record, ordinal)),
            }
        }

        record_groups.sort_by_key(scene_record_group_sort_key);
        edge_items.sort_by(|left, right| {
            left.z_index
                .cmp(&right.z_index)
                .then_with(|| left.ordinal.cmp(&right.ordinal))
        });

        Self {
            visible_document_bounds: frame.visible_document_bounds,
            record_groups,
            edge_items,
            tool_chrome: frame.interaction.clone(),
        }
    }

    pub fn record_groups(&self) -> &[CanvasSceneRecordGroup] {
        &self.record_groups
    }

    pub fn edge_items(&self) -> &[CanvasSceneLayerItem] {
        &self.edge_items
    }

    pub fn tool_chrome(&self) -> &CanvasPaintInteractionFrame {
        &self.tool_chrome
    }

    pub fn ordered_layer_items(&self) -> Vec<CanvasSceneLayerItem> {
        let mut items = Vec::with_capacity(
            self.edge_items.len()
                + self
                    .record_groups
                    .iter()
                    .map(|group| group.phases.len())
                    .sum::<usize>(),
        );
        items.extend(self.edge_items.iter().cloned());
        for group in &self.record_groups {
            items.extend(group.layer_items());
        }
        items
    }
}

fn scene_record_group_sort_key(group: &CanvasSceneRecordGroup) -> (u8, i32, usize) {
    (
        u8::from(group.selected || group.structurally_selected),
        group.z_index,
        group.ordinal,
    )
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasSceneRecordGroup {
    pub target: HitTarget,
    pub document_bounds: Bounds<Pixels>,
    pub view_bounds: Bounds<Pixels>,
    pub z_index: i32,
    pub ordinal: usize,
    pub record_index: usize,
    pub hidden: bool,
    pub locked: bool,
    pub hovered: bool,
    pub selected: bool,
    pub structurally_selected: bool,
    phases: Vec<CanvasSceneLayerPhase>,
}

impl CanvasSceneRecordGroup {
    fn from_record(record: &CanvasPaintRecord, ordinal: usize) -> Self {
        Self {
            target: record.target.clone(),
            document_bounds: record.document_bounds,
            view_bounds: record.view_bounds,
            z_index: record.z_index,
            ordinal,
            record_index: ordinal,
            hidden: record.hidden,
            locked: record.locked,
            hovered: record.hovered,
            selected: record.selected,
            structurally_selected: record.structurally_selected,
            phases: scene_record_phases(&record.target).to_vec(),
        }
    }

    pub fn phases(&self) -> &[CanvasSceneLayerPhase] {
        &self.phases
    }

    pub fn has_phase(&self, phase: CanvasSceneLayerPhase) -> bool {
        self.phases.contains(&phase)
    }

    pub fn layer_items(&self) -> impl Iterator<Item = CanvasSceneLayerItem> + '_ {
        self.phases
            .iter()
            .copied()
            .map(|phase| CanvasSceneLayerItem {
                phase,
                target: self.target.clone(),
                document_bounds: self.document_bounds,
                view_bounds: self.view_bounds,
                z_index: self.z_index,
                ordinal: self.ordinal,
                record_index: self.record_index,
            })
    }
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasSceneLayerItem {
    pub phase: CanvasSceneLayerPhase,
    pub target: HitTarget,
    pub document_bounds: Bounds<Pixels>,
    pub view_bounds: Bounds<Pixels>,
    pub z_index: i32,
    pub ordinal: usize,
    pub record_index: usize,
}

impl CanvasSceneLayerItem {
    fn from_record(
        record: &CanvasPaintRecord,
        ordinal: usize,
        phase: CanvasSceneLayerPhase,
    ) -> Self {
        Self {
            phase,
            target: record.target.clone(),
            document_bounds: record.document_bounds,
            view_bounds: record.view_bounds,
            z_index: record.z_index,
            ordinal,
            record_index: ordinal,
        }
    }
}

#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum CanvasSceneLayerPhase {
    DocumentUnderlay,
    EdgeBehindNodes,
    RecordBody,
    RecordWidget,
    RecordChrome,
    EdgeAboveNodes,
    ToolChrome,
    HostPortal,
}

fn scene_record_phases(target: &HitTarget) -> &'static [CanvasSceneLayerPhase] {
    match target {
        HitTarget::Node(_) => &[
            CanvasSceneLayerPhase::RecordBody,
            CanvasSceneLayerPhase::RecordWidget,
            CanvasSceneLayerPhase::RecordChrome,
        ],
        HitTarget::Shape(_) => &[
            CanvasSceneLayerPhase::RecordBody,
            CanvasSceneLayerPhase::RecordChrome,
        ],
        HitTarget::Handle { .. } => &[CanvasSceneLayerPhase::RecordChrome],
        HitTarget::Edge(_) => &[CanvasSceneLayerPhase::EdgeBehindNodes],
    }
}

#[derive(Debug)]
pub struct CanvasPreparedPaintFrame {
    pub(super) frame: CanvasPaintFrame,
    pub(super) labels: Vec<CanvasPreparedPaintLabel>,
    pub(super) label_indices: Vec<Option<usize>>,
}

impl CanvasPreparedPaintFrame {
    pub fn frame(&self) -> &CanvasPaintFrame {
        &self.frame
    }

    pub fn into_frame(self) -> CanvasPaintFrame {
        self.frame
    }

    pub fn prepared_label_count(&self) -> usize {
        self.labels.len()
    }

    pub fn record_count(&self) -> usize {
        self.frame.records.len()
    }

    pub fn has_prepared_label(&self, record_index: usize) -> bool {
        self.label_indices
            .get(record_index)
            .is_some_and(Option::is_some)
    }

    pub fn widget_overlay_frame(
        &self,
        options: CanvasWidgetOverlayOptions,
    ) -> CanvasWidgetOverlayFrame {
        self.frame.widget_overlay_frame(options)
    }
}

#[derive(Debug)]
pub(super) struct CanvasPreparedPaintLabel {
    pub(super) view_bounds: Bounds<Pixels>,
    pub(super) lines: Vec<WrappedLine>,
    pub(super) text_height: Pixels,
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintRecord {
    pub target: HitTarget,
    pub document_bounds: Bounds<Pixels>,
    pub view_bounds: Bounds<Pixels>,
    pub label: Option<CanvasPaintLabel>,
    pub edge_geometry: Option<CanvasPaintEdgeGeometry>,
    pub z_index: i32,
    pub hidden: bool,
    pub locked: bool,
    pub hovered: bool,
    pub selected: bool,
    pub structurally_selected: bool,
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintEdgeGeometry {
    pub view_path: CanvasRoutePath,
    pub visual_state: CanvasPaintWireVisualState,
}

#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum CanvasPaintWireVisualState {
    Committed,
    Hovered,
    Selected,
    SelectedHovered,
    PreviewFree,
    PreviewValidTarget,
    PreviewInvalidTarget,
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintLabel {
    pub text: String,
    pub document_bounds: Bounds<Pixels>,
    pub view_bounds: Bounds<Pixels>,
    pub color: Option<Hsla>,
}

#[derive(Clone, Debug, Default, PartialEq)]
pub struct CanvasPaintInteractionFrame {
    pub selection_bounds: Option<Bounds<Pixels>>,
    pub structural_selection_bounds: Option<Bounds<Pixels>>,
    pub connection_preview: Option<CanvasPaintConnectionPreview>,
    pub reconnect_handles: Vec<CanvasPaintReconnectHandle>,
    pub transform_handles: Vec<CanvasPaintTransformHandle>,
    pub snap_guides: Vec<CanvasPaintSnapGuide>,
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintConnectionPreview {
    pub source_view_position: Point<Pixels>,
    pub target_view_position: Point<Pixels>,
    pub edge_geometry: CanvasPaintEdgeGeometry,
    pub route_kind: CanvasEdgeRouteKind,
    pub visual_state: CanvasPaintWireVisualState,
    pub target_feedback: CanvasPaintConnectionTargetFeedback,
}

#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum CanvasPaintConnectionTargetState {
    Free,
    Valid,
    Invalid,
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintConnectionTargetFeedback {
    pub role: CanvasConnectionEndpointRole,
    pub state: CanvasPaintConnectionTargetState,
    pub view_bounds: Bounds<Pixels>,
}

#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum CanvasPaintReconnectEndpoint {
    Source,
    Target,
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintReconnectHandle {
    pub edge_id: EdgeId,
    pub endpoint: CanvasPaintReconnectEndpoint,
    pub shape: CanvasPaintReconnectHandleShape,
    pub view_bounds: Bounds<Pixels>,
    pub hit_bounds: Bounds<Pixels>,
    pub visual_bounds: Bounds<Pixels>,
}

#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum CanvasPaintReconnectHandleShape {
    SourcePlug,
    TargetSocket,
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintTransformHandle {
    pub target: CanvasTransformTarget,
    pub handle: crate::CanvasResizeHandle,
    pub view_bounds: Bounds<Pixels>,
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasPaintSnapGuide {
    pub axis: CanvasSnapAxis,
    pub view_start: Point<Pixels>,
    pub view_end: Point<Pixels>,
}

#[derive(Clone, Debug, Default, PartialEq)]
pub struct CanvasWidgetOverlayFrame {
    pub placements: Vec<CanvasWidgetOverlayPlacement>,
}

impl CanvasWidgetOverlayFrame {
    pub fn is_empty(&self) -> bool {
        self.placements.is_empty()
    }

    pub fn len(&self) -> usize {
        self.placements.len()
    }
}

#[derive(Clone, Debug, PartialEq)]
pub struct CanvasWidgetOverlayPlacement {
    pub target: HitTarget,
    pub document_bounds: Bounds<Pixels>,
    pub view_bounds: Bounds<Pixels>,
    pub z_index: i32,
    pub hit_priority: CanvasWidgetOverlayHitPriority,
}

#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
pub struct CanvasWidgetOverlayOptions {
    pub include_selected_nodes: bool,
    pub include_selected_shapes: bool,
    pub include_hidden: bool,
    pub include_locked: bool,
    pub hit_priority: CanvasWidgetOverlayHitPriority,
}

impl CanvasWidgetOverlayOptions {
    pub fn selected_nodes() -> Self {
        Self {
            include_selected_nodes: true,
            ..Self::default()
        }
    }

    pub fn selected_records() -> Self {
        Self {
            include_selected_nodes: true,
            include_selected_shapes: true,
            ..Self::default()
        }
    }

    pub fn with_locked(mut self, include_locked: bool) -> Self {
        self.include_locked = include_locked;
        self
    }

    pub fn with_hidden(mut self, include_hidden: bool) -> Self {
        self.include_hidden = include_hidden;
        self
    }

    pub fn with_hit_priority(mut self, hit_priority: CanvasWidgetOverlayHitPriority) -> Self {
        self.hit_priority = hit_priority;
        self
    }
}

#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
pub enum CanvasWidgetOverlayHitPriority {
    CanvasFirst,
    #[default]
    WidgetFirst,
}

pub fn collect_visible_records(
    model: &CanvasPaintModel,
    canvas_bounds: Bounds<Pixels>,
    options: CanvasPaintOptions,
) -> CanvasPaintFrame {
    let mut visible_document_bounds = model
        .viewport
        .view_bounds_to_document(Bounds::new(Point::default(), canvas_bounds.size));
    if options.cull_margin > Pixels::ZERO {
        visible_document_bounds = visible_document_bounds.dilate(options.cull_margin);
    }

    let hit_options = HitOptions {
        include_hidden: options.include_hidden,
        include_locked: true,
        include_handles: options.include_handles,
        margin: Pixels::ZERO,
    };
    let selection_scope = options.include_interaction_feedback.then(|| {
        resolve_selection_scope(
            model.document.as_ref(),
            model.interaction.selection(),
            CanvasRecordScopeOptions::structural_with_internal_edges(),
        )
    });
    let records = model
        .runtime
        .query_with_options(visible_document_bounds, hit_options)
        .map(|record| {
            let target = record.target.clone();
            let selected = options.include_interaction_feedback
                && selection_scope.as_ref().is_some_and(|scope| {
                    target_is_selected(&record.target, scope.normalized_selection())
                });
            let structurally_selected =
                target_is_structurally_selected(&record.target, selection_scope.as_ref());
            let hovered = options.include_interaction_feedback
                && model
                    .interaction
                    .hovered_target()
                    .is_some_and(|hovered| hovered == &target);
            let edge_geometry = paint_edge_geometry(
                model,
                &target,
                committed_wire_visual_state(selected || structurally_selected, hovered),
            );
            CanvasPaintRecord {
                label: paint_record_label(model, &target, record.bounds),
                target,
                document_bounds: record.bounds,
                view_bounds: model.viewport.document_bounds_to_view(record.bounds),
                edge_geometry,
                z_index: record.z_index,
                hidden: record.hidden,
                locked: record.locked,
                hovered,
                selected,
                structurally_selected,
            }
        })
        .collect();

    CanvasPaintFrame {
        visible_document_bounds,
        records,
        interaction: if options.include_interaction_feedback {
            interaction_frame(model, options, selection_scope.as_ref())
        } else {
            CanvasPaintInteractionFrame::default()
        },
    }
}

pub fn collect_widget_overlay_frame(
    frame: &CanvasPaintFrame,
    options: CanvasWidgetOverlayOptions,
) -> CanvasWidgetOverlayFrame {
    let placements = frame
        .records
        .iter()
        .filter(|record| record_requests_widget_overlay(record, options))
        .map(|record| CanvasWidgetOverlayPlacement {
            target: record.target.clone(),
            document_bounds: record.document_bounds,
            view_bounds: record.view_bounds,
            z_index: record.z_index,
            hit_priority: options.hit_priority,
        })
        .collect();

    CanvasWidgetOverlayFrame { placements }
}

pub fn prepaint_canvas_frame(
    model: &CanvasPaintModel,
    canvas_bounds: Bounds<Pixels>,
    options: CanvasPaintOptions,
    theme: CanvasPaintTheme,
    window: &mut Window,
) -> CanvasPreparedPaintFrame {
    let frame = collect_visible_records(model, canvas_bounds, options);
    prepare_canvas_frame(frame, theme, window)
}

pub fn prepare_canvas_frame(
    frame: CanvasPaintFrame,
    theme: CanvasPaintTheme,
    window: &mut Window,
) -> CanvasPreparedPaintFrame {
    let mut labels = Vec::new();
    let label_indices = frame
        .records
        .iter()
        .map(|record| {
            record.label.as_ref().and_then(|label| {
                let prepared = prepare_label(label, theme, window)?;
                let index = labels.len();
                labels.push(prepared);
                Some(index)
            })
        })
        .collect();

    CanvasPreparedPaintFrame {
        frame,
        labels,
        label_indices,
    }
}

fn interaction_frame(
    model: &CanvasPaintModel,
    options: CanvasPaintOptions,
    selection_scope: Option<&crate::CanvasResolvedSelectionScope>,
) -> CanvasPaintInteractionFrame {
    match model.interaction.state() {
        CanvasPaintInteractionState::Selecting { origin, current } => CanvasPaintInteractionFrame {
            selection_bounds: Some(
                model
                    .viewport
                    .document_bounds_to_view(bounds_from_points(*origin, *current)),
            ),
            structural_selection_bounds: None,
            connection_preview: None,
            reconnect_handles: Vec::new(),
            transform_handles: Vec::new(),
            snap_guides: Vec::new(),
        },
        CanvasPaintInteractionState::Connecting { source, current } => {
            CanvasPaintInteractionFrame {
                selection_bounds: None,
                structural_selection_bounds: structural_selection_bounds(model, selection_scope),
                connection_preview: connection_preview(
                    model,
                    source,
                    *current,
                    options.connection_preview_route.edge_route(),
                ),
                reconnect_handles: Vec::new(),
                transform_handles: Vec::new(),
                snap_guides: Vec::new(),
            }
        }
        CanvasPaintInteractionState::Reconnecting {
            edge_id,
            endpoint,
            fixed,
            current,
        } => CanvasPaintInteractionFrame {
            selection_bounds: None,
            structural_selection_bounds: structural_selection_bounds(model, selection_scope),
            connection_preview: reconnect_preview(
                model,
                edge_id,
                *endpoint,
                fixed,
                *current,
                options.connection_preview_route.edge_route(),
            ),
            reconnect_handles: Vec::new(),
            transform_handles: Vec::new(),
            snap_guides: Vec::new(),
        },
        CanvasPaintInteractionState::Transforming { snap_guides } => CanvasPaintInteractionFrame {
            selection_bounds: None,
            structural_selection_bounds: structural_selection_bounds(model, selection_scope),
            connection_preview: None,
            reconnect_handles: reconnect_handles_for_model(model),
            transform_handles: transform_handles_for_model(model),
            snap_guides: paint_snap_guides(model, snap_guides),
        },
        CanvasPaintInteractionState::Idle => CanvasPaintInteractionFrame {
            selection_bounds: None,
            structural_selection_bounds: structural_selection_bounds(model, selection_scope),
            connection_preview: None,
            reconnect_handles: reconnect_handles_for_model(model),
            transform_handles: transform_handles_for_model(model),
            snap_guides: Vec::new(),
        },
    }
}

fn structural_selection_bounds(
    model: &CanvasPaintModel,
    selection_scope: Option<&crate::CanvasResolvedSelectionScope>,
) -> Option<Bounds<Pixels>> {
    let selection_scope = selection_scope?;
    let facts = CanvasGeometryFacts::with_kind_registry(
        model.document.as_ref(),
        model.kind_registry.as_ref(),
    );
    let structural_bounds =
        facts.node_shape_bounds_for_records(selection_scope.paint_structural_records())?;
    if Some(structural_bounds) == facts.selected_bounds(model.interaction.selection()) {
        return None;
    }

    Some(model.viewport.document_bounds_to_view(structural_bounds))
}

fn paint_snap_guides(
    model: &CanvasPaintModel,
    guides: &[CanvasSnapGuide],
) -> Vec<CanvasPaintSnapGuide> {
    guides
        .iter()
        .map(|guide| CanvasPaintSnapGuide {
            axis: guide.axis,
            view_start: model.viewport.document_to_view(guide.document_start),
            view_end: model.viewport.document_to_view(guide.document_end),
        })
        .collect()
}

fn transform_handles_for_model(model: &CanvasPaintModel) -> Vec<CanvasPaintTransformHandle> {
    canvas_transform_handles(
        model.document.as_ref(),
        model.interaction.selection(),
        model.viewport,
        Some(model.kind_registry.as_ref()),
    )
    .into_iter()
    .map(|handle: CanvasTransformHandle| CanvasPaintTransformHandle {
        target: handle.target,
        handle: handle.handle,
        view_bounds: model
            .viewport
            .document_bounds_to_view(handle.document_bounds),
    })
    .collect()
}

fn reconnect_handles_for_model(model: &CanvasPaintModel) -> Vec<CanvasPaintReconnectHandle> {
    let facts = CanvasGeometryFacts::with_kind_registry(
        model.document.as_ref(),
        model.kind_registry.as_ref(),
    );
    model
        .interaction
        .selection()
        .selected_edges()
        .filter_map(|edge_id| {
            let edge = model.document.edge(edge_id)?;
            let source = facts.endpoint_position(&edge.source).ok()?;
            let target = facts.endpoint_position(&edge.target).ok()?;
            Some([
                reconnect_handle(
                    edge_id.clone(),
                    CanvasPaintReconnectEndpoint::Source,
                    model.viewport.document_to_view(source),
                ),
                reconnect_handle(
                    edge_id.clone(),
                    CanvasPaintReconnectEndpoint::Target,
                    model.viewport.document_to_view(target),
                ),
            ])
        })
        .flatten()
        .collect()
}

fn reconnect_handle(
    edge_id: EdgeId,
    endpoint: CanvasPaintReconnectEndpoint,
    center: Point<Pixels>,
) -> CanvasPaintReconnectHandle {
    let hit_bounds = Bounds::centered_at(
        center,
        size(RECONNECT_HANDLE_VIEW_SIZE, RECONNECT_HANDLE_VIEW_SIZE),
    );
    let visual_size = RECONNECT_HANDLE_VISUAL_SIZE
        .min(hit_bounds.size.width)
        .min(hit_bounds.size.height);
    CanvasPaintReconnectHandle {
        edge_id,
        endpoint,
        shape: reconnect_handle_shape(endpoint),
        view_bounds: hit_bounds,
        hit_bounds,
        visual_bounds: Bounds::centered_at(center, size(visual_size, visual_size)),
    }
}

fn reconnect_handle_shape(
    endpoint: CanvasPaintReconnectEndpoint,
) -> CanvasPaintReconnectHandleShape {
    match endpoint {
        CanvasPaintReconnectEndpoint::Source => CanvasPaintReconnectHandleShape::SourcePlug,
        CanvasPaintReconnectEndpoint::Target => CanvasPaintReconnectHandleShape::TargetSocket,
    }
}

fn connection_preview(
    model: &CanvasPaintModel,
    source: &CanvasEndpoint,
    current: Point<Pixels>,
    route: CanvasEdgeRoute,
) -> Option<CanvasPaintConnectionPreview> {
    let facts = CanvasGeometryFacts::with_kind_registry(
        model.document.as_ref(),
        model.kind_registry.as_ref(),
    );
    let source = facts.endpoint_position(source).ok()?;
    let target = connection_preview_endpoint_target(
        model,
        CanvasConnectionEndpointRole::Target,
        source,
        current,
    );
    Some(connection_preview_frame(
        model,
        source,
        target.document_position,
        route,
        target.feedback,
    ))
}

fn reconnect_preview(
    model: &CanvasPaintModel,
    edge_id: &EdgeId,
    endpoint: CanvasConnectionEndpointRole,
    fixed: &CanvasEndpoint,
    current: Point<Pixels>,
    fallback_route: CanvasEdgeRoute,
) -> Option<CanvasPaintConnectionPreview> {
    let facts = CanvasGeometryFacts::with_kind_registry(
        model.document.as_ref(),
        model.kind_registry.as_ref(),
    );
    let fixed = facts.endpoint_position(fixed).ok()?;
    let moving = connection_preview_endpoint_target(model, endpoint, fixed, current);
    let route = model
        .document
        .edge(edge_id)
        .map(|edge| edge.route.clone())
        .unwrap_or(fallback_route);
    Some(match endpoint {
        CanvasConnectionEndpointRole::Source => connection_preview_frame(
            model,
            moving.document_position,
            fixed,
            route,
            moving.feedback,
        ),
        CanvasConnectionEndpointRole::Target => connection_preview_frame(
            model,
            fixed,
            moving.document_position,
            route,
            moving.feedback,
        ),
    })
}

fn connection_preview_frame(
    model: &CanvasPaintModel,
    source: Point<Pixels>,
    target: Point<Pixels>,
    route: CanvasEdgeRoute,
    target_feedback: CanvasPaintConnectionTargetFeedback,
) -> CanvasPaintConnectionPreview {
    let route_kind = route.kind.clone();
    let visual_state = preview_wire_visual_state(target_feedback.state);
    let mut edge = CanvasEdge::new(
        "__connection_preview",
        CanvasEndpoint::new("__connection_preview_source", None::<&str>),
        CanvasEndpoint::new("__connection_preview_target", None::<&str>),
    );
    edge.route = route;
    let path = CanvasDefaultEdgeRouter.route_edge(CanvasRouteRequest {
        edge: &edge,
        source,
        target,
    });
    CanvasPaintConnectionPreview {
        source_view_position: model.viewport.document_to_view(source),
        target_view_position: model.viewport.document_to_view(target),
        edge_geometry: CanvasPaintEdgeGeometry {
            view_path: route_path_to_view(&path, model.viewport),
            visual_state,
        },
        route_kind,
        visual_state,
        target_feedback,
    }
}

fn preview_wire_visual_state(
    state: CanvasPaintConnectionTargetState,
) -> CanvasPaintWireVisualState {
    match state {
        CanvasPaintConnectionTargetState::Free => CanvasPaintWireVisualState::PreviewFree,
        CanvasPaintConnectionTargetState::Valid => CanvasPaintWireVisualState::PreviewValidTarget,
        CanvasPaintConnectionTargetState::Invalid => {
            CanvasPaintWireVisualState::PreviewInvalidTarget
        }
    }
}

#[derive(Clone, Debug, PartialEq)]
struct CanvasConnectionPreviewEndpointTarget {
    document_position: Point<Pixels>,
    feedback: CanvasPaintConnectionTargetFeedback,
}

fn connection_preview_endpoint_target(
    model: &CanvasPaintModel,
    role: CanvasConnectionEndpointRole,
    fixed: Point<Pixels>,
    current: Point<Pixels>,
) -> CanvasConnectionPreviewEndpointTarget {
    let facts = CanvasGeometryFacts::with_kind_registry(
        model.document.as_ref(),
        model.kind_registry.as_ref(),
    );
    let records = model
        .runtime
        .precise_hit_test_with_facts(facts, current, connection_hit_options())
        .collect::<Vec<_>>();

    for record in records {
        match &record.target {
            HitTarget::Handle { node_id, handle_id } => {
                let Some(node) = model.document.node(node_id) else {
                    continue;
                };
                let Some(handle) = node.handle(Some(handle_id)) else {
                    continue;
                };
                let endpoint = CanvasEndpoint {
                    node_id: node_id.clone(),
                    handle_id: Some(handle_id.clone()),
                };
                let position = facts.endpoint_position(&endpoint).unwrap_or(current);
                let state = if handle.is_pickable_connection_endpoint(role) && position != fixed {
                    CanvasPaintConnectionTargetState::Valid
                } else {
                    CanvasPaintConnectionTargetState::Invalid
                };
                return CanvasConnectionPreviewEndpointTarget {
                    document_position: if state == CanvasPaintConnectionTargetState::Valid {
                        position
                    } else {
                        current
                    },
                    feedback: connection_target_feedback(model, role, state, position),
                };
            }
            HitTarget::Node(node_id) => {
                let endpoint = CanvasEndpoint {
                    node_id: node_id.clone(),
                    handle_id: None,
                };
                let position = facts.endpoint_position(&endpoint).unwrap_or(current);
                let state = if position != fixed {
                    CanvasPaintConnectionTargetState::Valid
                } else {
                    CanvasPaintConnectionTargetState::Invalid
                };
                return CanvasConnectionPreviewEndpointTarget {
                    document_position: if state == CanvasPaintConnectionTargetState::Valid {
                        position
                    } else {
                        current
                    },
                    feedback: connection_target_feedback(model, role, state, position),
                };
            }
            HitTarget::Edge(_) | HitTarget::Shape(_) => {}
        }
    }

    CanvasConnectionPreviewEndpointTarget {
        document_position: current,
        feedback: connection_target_feedback(
            model,
            role,
            CanvasPaintConnectionTargetState::Free,
            current,
        ),
    }
}

fn connection_target_feedback(
    model: &CanvasPaintModel,
    role: CanvasConnectionEndpointRole,
    state: CanvasPaintConnectionTargetState,
    document_position: Point<Pixels>,
) -> CanvasPaintConnectionTargetFeedback {
    CanvasPaintConnectionTargetFeedback {
        role,
        state,
        view_bounds: Bounds::centered_at(
            model.viewport.document_to_view(document_position),
            size(
                CONNECTION_TARGET_FEEDBACK_VIEW_SIZE,
                CONNECTION_TARGET_FEEDBACK_VIEW_SIZE,
            ),
        ),
    }
}

fn target_is_selected(target: &HitTarget, selection: &CanvasSelection) -> bool {
    selection.contains_target(target)
}

fn committed_wire_visual_state(selected: bool, hovered: bool) -> CanvasPaintWireVisualState {
    match (selected, hovered) {
        (true, true) => CanvasPaintWireVisualState::SelectedHovered,
        (true, false) => CanvasPaintWireVisualState::Selected,
        (false, true) => CanvasPaintWireVisualState::Hovered,
        (false, false) => CanvasPaintWireVisualState::Committed,
    }
}

fn target_is_structurally_selected(
    target: &HitTarget,
    scope: Option<&CanvasResolvedSelectionScope>,
) -> bool {
    let Some(scope) = scope else {
        return false;
    };
    let Some(record_id) = record_id_for_target(target) else {
        return false;
    };

    scope.contains_paint_structural_record(&record_id)
}

fn record_id_for_target(target: &HitTarget) -> Option<CanvasRecordId> {
    match target {
        HitTarget::Node(id) => Some(CanvasRecordId::Node(id.clone())),
        HitTarget::Edge(id) => Some(CanvasRecordId::Edge(id.clone())),
        HitTarget::Shape(id) => Some(CanvasRecordId::Shape(id.clone())),
        HitTarget::Handle { .. } => None,
    }
}

fn record_requests_widget_overlay(
    record: &CanvasPaintRecord,
    options: CanvasWidgetOverlayOptions,
) -> bool {
    if !record.selected
        || (record.hidden && !options.include_hidden)
        || (record.locked && !options.include_locked)
    {
        return false;
    }

    match &record.target {
        HitTarget::Node(_) => options.include_selected_nodes,
        HitTarget::Shape(_) => options.include_selected_shapes,
        HitTarget::Edge(_) | HitTarget::Handle { .. } => false,
    }
}

fn bounds_from_points(a: Point<Pixels>, b: Point<Pixels>) -> Bounds<Pixels> {
    Bounds::from_corners(
        Point::new(a.x.min(b.x), a.y.min(b.y)),
        Point::new(a.x.max(b.x), a.y.max(b.y)),
    )
}

fn prepare_label(
    label: &CanvasPaintLabel,
    theme: CanvasPaintTheme,
    window: &mut Window,
) -> Option<CanvasPreparedPaintLabel> {
    let text = label.text.trim();
    if text.is_empty()
        || label.view_bounds.size.width <= Pixels::ZERO
        || label.view_bounds.size.height <= Pixels::ZERO
        || !positive_pixels(theme.label_font_size)
        || !positive_pixels(theme.label_line_height)
    {
        return None;
    }

    let mut text_style = window.text_style();
    text_style.color = label.color.unwrap_or(theme.label_color);
    let run = TextRun {
        len: text.len(),
        ..text_style.to_run(text.len())
    };

    let Some(lines) = window
        .text_system()
        .shape_text(
            SharedString::new(text),
            theme.label_font_size,
            &[run],
            Some(label.view_bounds.size.width),
            label_line_clamp(theme, label.view_bounds),
        )
        .ok()
    else {
        return None;
    };

    let text_height = lines.iter().fold(Pixels::ZERO, |height, line| {
        height + line.size(theme.label_line_height).height
    });

    Some(CanvasPreparedPaintLabel {
        view_bounds: label.view_bounds,
        lines: lines.into_iter().collect(),
        text_height,
    })
}

pub(super) fn label_line_clamp(theme: CanvasPaintTheme, bounds: Bounds<Pixels>) -> Option<usize> {
    let max_lines_by_height =
        (bounds.size.height.as_f32() / theme.label_line_height.as_f32()).floor() as usize;
    let max_lines = max_lines_by_height.max(1);
    Some(
        theme
            .label_line_clamp
            .map_or(max_lines, |clamp| clamp.max(1).min(max_lines)),
    )
}

fn paint_record_label(
    model: &CanvasPaintModel,
    target: &HitTarget,
    document_bounds: Bounds<Pixels>,
) -> Option<CanvasPaintLabel> {
    let label = match target {
        HitTarget::Node(id) => model
            .document
            .node(id)
            .and_then(|node| model.kind_registry.node_label(node)),
        HitTarget::Shape(id) => model
            .document
            .shape(id)
            .and_then(|shape| model.kind_registry.shape_label(shape)),
        HitTarget::Edge(_) | HitTarget::Handle { .. } => None,
    }?;

    Some(resolve_paint_label(model, label, document_bounds))
}

fn resolve_paint_label(
    model: &CanvasPaintModel,
    label: CanvasKindLabel,
    document_bounds: Bounds<Pixels>,
) -> CanvasPaintLabel {
    let document_bounds = label_document_bounds(document_bounds, label.inset);
    CanvasPaintLabel {
        text: label.text,
        document_bounds,
        view_bounds: model.viewport.document_bounds_to_view(document_bounds),
        color: label.color.as_deref().and_then(parse_color),
    }
}

fn label_document_bounds(bounds: Bounds<Pixels>, inset: Pixels) -> Bounds<Pixels> {
    if !inset.as_f32().is_finite() || inset <= Pixels::ZERO {
        return bounds;
    }

    let max_inset = bounds.size.width.min(bounds.size.height) * 0.5;
    bounds.inset(inset.min(max_inset))
}

fn paint_edge_geometry(
    model: &CanvasPaintModel,
    target: &HitTarget,
    visual_state: CanvasPaintWireVisualState,
) -> Option<CanvasPaintEdgeGeometry> {
    let HitTarget::Edge(id) = target else {
        return None;
    };
    let geometry = model.runtime.edge_geometry(id)?;
    Some(CanvasPaintEdgeGeometry {
        view_path: route_path_to_view(&geometry.path, model.viewport),
        visual_state,
    })
}

fn route_path_to_view(path: &CanvasRoutePath, viewport: CanvasViewport) -> CanvasRoutePath {
    CanvasRoutePath::new(path.segments.iter().map(|segment| match segment {
        CanvasRouteSegment::Line { from, to } => CanvasRouteSegment::Line {
            from: viewport.document_to_view(*from),
            to: viewport.document_to_view(*to),
        },
        CanvasRouteSegment::CubicBezier {
            from,
            control_1,
            control_2,
            to,
        } => CanvasRouteSegment::CubicBezier {
            from: viewport.document_to_view(*from),
            control_1: viewport.document_to_view(*control_1),
            control_2: viewport.document_to_view(*control_2),
            to: viewport.document_to_view(*to),
        },
    }))
}