//! Width points, Liquify, Puppet Warp and Perspective Grid commands and tools.

use serde_json::json;
use vectorcraft_geom::{PathData, Point, Rect, Shape};
use vectorcraft_tools::distort::perspective::{PerspectiveGrid, Plane};
use vectorcraft_tools::{Mods, PointerEvent, PointerKind, ToolKey};

use super::*;

fn session() -> Session {
    let mut s = Session::new();
    s.execute("file.new", &json!({"width": 800, "height": 600})).unwrap();
    s
}

fn rect(s: &mut Session, x: f64, y: f64, w: f64, h: f64) -> NodeId {
    let r = s.execute("shape.rectangle", &json!({"x": x, "y": y, "width": w, "height": h})).unwrap();
    NodeId(r["id"].as_u64().unwrap())
}

fn line(s: &mut Session) -> NodeId {
    let r = s.execute("shape.line", &json!({"x1": 100, "y1": 300, "x2": 500, "y2": 300})).unwrap();
    let id = NodeId(r["id"].as_u64().unwrap());
    s.execute("stroke.set", &json!({"ids": [id.0], "weight": 10})).unwrap();
    id
}

fn path(s: &Session, id: NodeId) -> PathData {
    s.doc().unwrap().doc.node(id).unwrap().path_data().unwrap().clone()
}

fn profile(s: &Session, id: NodeId) -> Option<Vec<(f64, f64, f64)>> {
    s.doc().unwrap().doc.node(id).unwrap().appearance.stroke().unwrap().profile.as_ref().map(|p| p.points.clone())
}

fn undo_len(s: &Session) -> usize {
    s.doc().unwrap().history.undo.len()
}

fn gesture(s: &mut Session, tool: &str, pts: &[(f64, f64)], mods: Mods) {
    let v = ViewInfo::default();
    s.select_tool(tool, v).unwrap();
    for (i, (x, y)) in pts.iter().enumerate() {
        let kind = if i == 0 {
            PointerKind::Down
        } else if i == pts.len() - 1 {
            PointerKind::Up
        } else {
            PointerKind::Drag
        };
        s.pointer(&PointerEvent::new(kind, *x, *y).with_mods(mods), v).unwrap();
    }
}

fn close(a: Point, b: Point, tol: f64) -> bool {
    a.distance(b) <= tol
}

// ---------- width ----------

#[test]
fn width_point_set_creates_profile_and_undoes() {
    let mut s = session();
    let id = line(&mut s);
    let n = undo_len(&s);
    let r = s.execute("stroke.widthPoint.set", &json!({"id": id.0, "t": 0.5, "left": 10, "right": 5})).unwrap();
    assert_eq!(r["index"], json!(1));
    assert_eq!(profile(&s, id).unwrap(), vec![(0.0, 1.0, 1.0), (0.5, 2.0, 1.0), (1.0, 1.0, 1.0)]);
    assert_eq!(undo_len(&s), n + 1);
    s.execute("edit.undo", &json!({})).unwrap();
    assert_eq!(profile(&s, id), None);
}

#[test]
fn width_point_move_and_remove() {
    let mut s = session();
    let id = line(&mut s);
    s.execute("stroke.widthPoint.set", &json!({"id": id.0, "t": 0.5, "left": 10, "right": 10})).unwrap();
    let r = s.execute("stroke.widthPoint.set", &json!({"id": id.0, "t": 0.25, "left": 10, "right": 10, "index": 1})).unwrap();
    assert_eq!(r["index"], json!(1));
    assert_eq!(profile(&s, id).unwrap()[1], (0.25, 2.0, 2.0));
    assert_eq!(profile(&s, id).unwrap().len(), 3);
    s.execute("stroke.widthPoint.remove", &json!({"id": id.0, "index": 1})).unwrap();
    assert_eq!(profile(&s, id).unwrap().len(), 2);
    assert!(s.execute("stroke.widthPoint.remove", &json!({"id": id.0, "index": 7})).is_err());
    assert!(s.execute("stroke.widthPoint.set", &json!({"id": id.0, "t": 0.5, "left": -1, "right": 1})).is_err());
}

#[test]
fn width_profile_set_and_clear() {
    let mut s = session();
    let id = line(&mut s);
    s.execute("stroke.widthProfile.set", &json!({"ids": [id.0], "points": [[1, 0, 0], [0, 0.5, 0.5]]})).unwrap();
    assert_eq!(profile(&s, id).unwrap(), vec![(0.0, 0.5, 0.5), (1.0, 0.0, 0.0)]);
    s.execute("stroke.widthProfile.set", &json!({"ids": [id.0], "points": null})).unwrap();
    assert_eq!(profile(&s, id), None);
}

#[test]
fn width_tool_gesture_is_one_undo_step() {
    let mut s = session();
    let id = line(&mut s);
    let n = undo_len(&s);
    gesture(&mut s, "width", &[(300.0, 301.0), (300.0, 310.0), (300.0, 320.0)], Mods::default());
    let p = profile(&s, id).unwrap();
    assert_eq!(p.len(), 3);
    // The last drag sample (10 pt from the path) sets both sides: factor 10 / (10 / 2) = 2.
    assert!((p[1].0 - 0.5).abs() < 1e-3 && (p[1].1 - 2.0).abs() < 1e-6 && (p[1].2 - 2.0).abs() < 1e-6, "{p:?}");
    assert_eq!(undo_len(&s), n + 1);
    // Delete removes the selected width point.
    s.tool_key(ToolKey::Delete, Mods::default(), ViewInfo::default()).unwrap();
    assert_eq!(profile(&s, id).unwrap().len(), 2);
}

// ---------- liquify ----------

fn warp_params() -> serde_json::Value {
    json!({"tool": "warp", "points": [[300, 150], [340, 150], [380, 150]], "diameter": 100, "intensity": 100})
}

#[test]
fn liquify_is_deterministic_and_localized() {
    let run = || {
        let mut s = session();
        let a = rect(&mut s, 100.0, 100.0, 200.0, 200.0);
        let b = rect(&mut s, 500.0, 400.0, 100.0, 100.0);
        s.execute("select.all", &json!({})).unwrap();
        s.execute("object.liquify", &warp_params()).unwrap();
        (path(&s, a), path(&s, b))
    };
    let (a1, b1) = run();
    let (a2, b2) = run();
    assert_eq!(a1, a2);
    assert_eq!(b1, b2);
    // The far rectangle is untouched; the right edge of the first bulged right near y = 150.
    assert_eq!(b1.bounds().unwrap(), Rect::new(500.0, 400.0, 600.0, 500.0));
    let bb = a1.bounds().unwrap();
    assert!(bb.x1 > 320.0 && bb.x0 == 100.0 && bb.y1 == 300.0, "{bb:?}");
    assert!(a1.anchor_count() > 4);
}

#[test]
fn liquify_without_selection_hits_paths_under_the_brush() {
    let mut s = session();
    let a = rect(&mut s, 100.0, 100.0, 200.0, 200.0);
    let b = rect(&mut s, 500.0, 400.0, 100.0, 100.0);
    s.execute("select.set", &json!({"ids": []})).unwrap();
    let r = s.execute("object.liquify", &json!({"tool": "pucker", "points": [[550, 450]], "diameter": 150, "intensity": 1})).unwrap();
    assert_eq!(r["ids"], json!([b.0]));
    assert_eq!(path(&s, a).bounds().unwrap(), Rect::new(100.0, 100.0, 300.0, 300.0));
    assert!(path(&s, b).bounds().unwrap().width() < 100.0);
}

#[test]
fn liquify_tool_replays_from_the_journal() {
    let mut s = session();
    let a = rect(&mut s, 100.0, 100.0, 200.0, 200.0);
    s.execute("select.set", &json!({"ids": [a.0]})).unwrap();
    let n = undo_len(&s);
    s.select_tool("twirl", ViewInfo::default()).unwrap();
    s.set_tool_option("diameter", &json!(120));
    gesture(&mut s, "twirl", &[(300.0, 200.0), (302.0, 210.0), (305.0, 220.0), (305.0, 230.0)], Mods::default());
    assert_eq!(undo_len(&s), n + 1);
    let after = path(&s, a);
    assert_ne!(after, path(&session_with_rect(), a));
    let (cmd, params) = s.journal.last().unwrap().clone();
    assert_eq!(cmd, "object.liquify");
    let mut t = session_with_rect();
    t.execute("select.set", &json!({"ids": [a.0]})).unwrap();
    t.execute(&cmd, &params).unwrap();
    assert_eq!(path(&t, a), after);
}

fn session_with_rect() -> Session {
    let mut s = session();
    rect(&mut s, 100.0, 100.0, 200.0, 200.0);
    s
}

// ---------- puppet warp ----------

#[test]
fn puppet_warp_satisfies_pins_and_keeps_area() {
    let mut s = session();
    let a = rect(&mut s, 100.0, 100.0, 300.0, 100.0);
    let n = undo_len(&s);
    s.execute("object.puppetWarp", &json!({"id": a.0, "pins": [[120, 150], [250, 150], [380, 150]], "moved": [[120, 150], [250, 150], [370, 90]]}))
        .unwrap();
    let p = path(&s, a);
    let area0 = 300.0 * 100.0;
    let area1 = p.to_bezpath().area().abs();
    assert!((area1 / area0 - 1.0).abs() < 0.08, "area {area1}");
    // The pinned left end stays; the right end rose.
    let bb = p.bounds().unwrap();
    assert!((bb.x0 - 100.0).abs() < 6.0, "{bb:?}");
    assert!(bb.y0 < 80.0, "{bb:?}");
    assert_eq!(undo_len(&s), n + 1);
    s.execute("edit.undo", &json!({})).unwrap();
    assert_eq!(path(&s, a).bounds().unwrap(), Rect::new(100.0, 100.0, 400.0, 200.0));
    assert!(s.execute("object.puppetWarp", &json!({"id": a.0, "pins": [[1, 1]], "moved": []})).is_err());
}

#[test]
fn puppet_tool_drag_warps_selection() {
    let mut s = session();
    let a = rect(&mut s, 100.0, 100.0, 300.0, 100.0);
    s.execute("select.set", &json!({"ids": [a.0]})).unwrap();
    let v = ViewInfo::default();
    s.select_tool("puppetWarp", v).unwrap();
    // The automatic pins show at once, one in the middle of each end: drag the right end's up.
    let pins = s.execute("object.puppetWarp.pins", &json!({})).unwrap()["moved"].clone();
    let right = pins
        .as_array()
        .unwrap()
        .iter()
        .map(|q| (q[0].as_f64().unwrap(), q[1].as_f64().unwrap()))
        .fold((0.0, 0.0), |a, q| if q.0 > a.0 { q } else { a });
    assert!(right.0 > 350.0, "{pins}");
    let n = undo_len(&s);
    s.pointer(&PointerEvent::new(PointerKind::Down, right.0, right.1), v).unwrap();
    s.pointer(&PointerEvent::new(PointerKind::Drag, right.0, right.1 - 30.0), v).unwrap();
    s.pointer(&PointerEvent::new(PointerKind::Up, right.0, right.1 - 30.0), v).unwrap();
    assert_eq!(undo_len(&s), n + 1);
    assert_eq!(s.journal.last().unwrap().0, "object.puppetWarp");
    assert!(path(&s, a).bounds().unwrap().y0 < 95.0);
}

// ---------- perspective ----------

fn grid(s: &Session) -> PerspectiveGrid {
    PerspectiveGrid::from_doc(&s.doc().unwrap().doc).unwrap()
}

#[test]
fn grid_show_and_plane_are_view_state() {
    let mut s = session();
    let n = undo_len(&s);
    assert_eq!(s.execute("perspective.grid.show", &json!({})).unwrap(), json!({"visible": true}));
    s.execute("perspective.plane.set", &json!({"plane": "ground"})).unwrap();
    assert_eq!(grid(&s).plane, Plane::Ground);
    assert_eq!(undo_len(&s), n);
    assert_eq!(s.execute("perspective.grid.show", &json!({})).unwrap(), json!({"visible": false}));
    assert!(s.execute("perspective.plane.set", &json!({"plane": "up"})).is_err());
    let ov = s.overlays(ViewInfo::default());
    assert!(ov.is_empty(), "hidden grid draws nothing with the selection tool");
    s.select_tool("perspectiveGrid", ViewInfo::default()).unwrap();
    assert!(s.overlays(ViewInfo::default()).len() > 20);
}

#[test]
fn the_grid_hides_while_a_perspective_tool_is_chosen() {
    // #321: choosing the Perspective Grid tool showed the grid for good.
    let mut s = session();
    let v = ViewInfo::default();
    for tool in ["perspectiveGrid", "perspectiveSelection"] {
        s.select_tool(tool, v).unwrap();
        assert!(s.overlays(v).len() > 20, "{tool}");
        let n = undo_len(&s);
        assert_eq!(s.execute("perspective.grid.show", &json!({})).unwrap(), json!({"visible": false}));
        assert!(s.overlays(v).is_empty(), "{tool}: the hidden grid still draws");
        assert_eq!(undo_len(&s), n);
        // Choosing the tool again shows it again.
        s.select_tool(tool, v).unwrap();
        assert!(s.overlays(v).len() > 20, "{tool}");
        s.execute("perspective.grid.show", &json!({"visible": false})).unwrap();
        s.select_tool("selection", v).unwrap();
    }
}

#[test]
fn a_hidden_grid_stays_hidden_back_from_a_temporary_tool() {
    // Cmd-dragging with a perspective tool borrows the Selection tool; going back to the
    // perspective tool is not choosing it, so the grid hidden meanwhile stays hidden.
    let mut s = session();
    let v = ViewInfo::default();
    s.select_tool("perspectiveGrid", v).unwrap();
    s.execute("perspective.grid.show", &json!({"visible": false})).unwrap();
    s.switch_tool("selection", v).unwrap();
    s.switch_tool("perspectiveGrid", v).unwrap();
    assert!(s.overlays(v).is_empty());
    s.select_tool("selection", v).unwrap();
    s.select_tool("perspectiveGrid", v).unwrap();
    assert!(s.overlays(v).len() > 20, "choosing it shows the grid");
}

#[test]
fn grid_preset_and_set_are_undoable() {
    let mut s = session();
    s.execute("perspective.grid.preset", &json!({"kind": 3})).unwrap();
    assert_eq!(grid(&s).kind, 3);
    s.execute("perspective.grid.set", &json!({"cell": 40, "horizon": 200})).unwrap();
    assert_eq!((grid(&s).cell, grid(&s).horizon), (40.0, 200.0));
    s.execute("edit.undo", &json!({})).unwrap();
    assert_eq!(grid(&s).kind, 3);
    assert_ne!(grid(&s).cell, 40.0);
    assert!(s.execute("perspective.grid.set", &json!({"distance": 0})).is_err());
    assert!(s.execute("perspective.grid.preset", &json!({"kind": 4})).is_err());
    // The grid is saved with the document.
    let saved = serde_json::to_value(&*s.doc().unwrap().doc).unwrap();
    assert_eq!(saved["unknown"]["perspectiveGrid"]["kind"], json!(3));
}

#[test]
fn attach_projects_onto_the_plane_and_releases() {
    let mut s = session();
    s.execute("perspective.grid.preset", &json!({"kind": 2})).unwrap();
    let a = rect(&mut s, 450.0, 300.0, 100.0, 100.0);
    s.execute("perspective.attach", &json!({"ids": [a.0], "plane": "right"})).unwrap();
    let g = grid(&s);
    assert_eq!(g.attached_plane(a), Some(Plane::Right));
    // Every anchor lies on the plane: its plane coordinates form an axis-aligned rectangle.
    let p = path(&s, a);
    let q: Vec<Point> = p.anchors().map(|(_, _, an)| g.to_plane(Plane::Right, an.p).unwrap()).collect();
    let xs: Vec<f64> = q.iter().map(|v| v.x).collect();
    let ys: Vec<f64> = q.iter().map(|v| v.y).collect();
    for v in &q {
        assert!(xs.iter().filter(|x| (*x - v.x).abs() < 1e-6).count() == 2 && ys.iter().filter(|y| (*y - v.y).abs() < 1e-6).count() == 2, "{q:?}");
    }
    // The dragged corners are kept.
    assert!(p.anchors().any(|(_, _, an)| close(an.p, Point::new(450.0, 300.0), 1e-6)));
    assert!(p.anchors().any(|(_, _, an)| close(an.p, Point::new(550.0, 400.0), 1e-6)));
    s.execute("perspective.release", &json!({"ids": [a.0]})).unwrap();
    assert_eq!(grid(&s).attached_plane(a), None);
    assert_eq!(path(&s, a), p);
    s.execute("edit.undo", &json!({})).unwrap();
    s.execute("edit.undo", &json!({})).unwrap();
    assert_eq!(path(&s, a).bounds().unwrap(), Rect::new(450.0, 300.0, 550.0, 400.0));
}

#[test]
fn rectangle_tool_draws_in_perspective_on_the_active_plane() {
    let mut s = session();
    s.execute("perspective.grid.preset", &json!({"kind": 2})).unwrap();
    s.execute("perspective.plane.set", &json!({"plane": "left"})).unwrap();
    // Snap to Grid (on by default) would move the dragged corners onto gridlines.
    s.execute("perspective.grid.snap", &json!({"on": false})).unwrap();
    let n = undo_len(&s);
    gesture(&mut s, "rectangle", &[(300.0, 320.0), (330.0, 360.0), (350.0, 400.0)], Mods::default());
    assert_eq!(undo_len(&s), n + 1);
    let (cmd, params) = s.journal.last().unwrap().clone();
    assert_eq!(cmd, "perspective.draw");
    assert_eq!(params["command"], json!("shape.rectangle"));
    let id = *s.doc().unwrap().selection.objects.last().unwrap();
    assert_eq!(grid(&s).attached_plane(id), Some(Plane::Left));
    let p = path(&s, id);
    assert!(p.anchors().any(|(_, _, an)| close(an.p, Point::new(300.0, 320.0), 1e-6)));
    // Not a plain rectangle any more: the top edge slopes toward the left vanishing point.
    let ys: Vec<f64> = p.anchors().map(|(_, _, an)| an.p.y).collect();
    assert!(ys.iter().any(|y| (y - 320.0).abs() > 0.5 && (y - 400.0).abs() > 0.5), "{ys:?}");
    s.execute("edit.undo", &json!({})).unwrap();
    assert!(s.doc().unwrap().doc.node(id).is_none());
}

#[test]
fn perspective_selection_moves_within_the_plane() {
    let mut s = session();
    s.execute("perspective.grid.preset", &json!({"kind": 2})).unwrap();
    let a = rect(&mut s, 450.0, 380.0, 60.0, 60.0);
    s.execute("perspective.attach", &json!({"ids": [a.0], "plane": "right"})).unwrap();
    // Snap to Grid (on by default) would land the moved edges on gridlines.
    s.execute("perspective.grid.snap", &json!({"on": false})).unwrap();
    let g = grid(&s);
    let before: Vec<Point> = path(&s, a).anchors().map(|(_, _, an)| g.to_plane(Plane::Right, an.p).unwrap()).collect();
    let centre = before.iter().fold(vectorcraft_geom::Vec2::ZERO, |a, p| a + p.to_vec2()) / before.len() as f64;
    let from = g.to_page(Plane::Right, centre.to_point()).unwrap();
    let to = g.to_page(Plane::Right, (centre + vectorcraft_geom::Vec2::new(40.0, 20.0)).to_point()).unwrap();
    let n = undo_len(&s);
    gesture(&mut s, "perspectiveSelection", &[(from.x, from.y), (to.x, to.y), (to.x, to.y)], Mods::default());
    assert_eq!(undo_len(&s), n + 1);
    let after: Vec<Point> = path(&s, a).anchors().map(|(_, _, an)| g.to_plane(Plane::Right, an.p).unwrap()).collect();
    for (b, c) in before.iter().zip(&after) {
        assert!((*c - *b - vectorcraft_geom::Vec2::new(40.0, 20.0)).hypot() < 1e-6, "{b:?} → {c:?}");
    }
}

#[test]
fn perspective_move_attaches_loose_objects_to_the_given_plane() {
    let mut s = session();
    s.execute("perspective.grid.preset", &json!({"kind": 1})).unwrap();
    let a = rect(&mut s, 250.0, 380.0, 50.0, 50.0);
    s.execute("perspective.move", &json!({"ids": [a.0], "from": [260, 390], "to": [270, 390], "plane": "ground"})).unwrap();
    assert_eq!(grid(&s).attached_plane(a), Some(Plane::Ground));
    assert!(s.execute("perspective.attach", &json!({"ids": [a.0], "plane": "none"})).is_err());
}