//! Hit-test functions for mouse interaction: agent hover, coffee machine
//! click-to-open, and furniture tooltip detection.

use std::time::SystemTime;

use pixtuoid_core::{AgentId, SceneState};

use crate::tui::layout::{Layout, Size};
use crate::tui::pet::PetKind;
use crate::tui::pixel_painter::character_anchor;
use crate::tui::pose;

/// Hit-test the mouse cursor against each agent's current sprite footprint.
/// Returns the agent under `(mx, my)` (in terminal cell coordinates), or
/// `None` if no agent occupies that cell.
///
/// The character sprite is 8×12 pixels, which in cell space is 8 cells
/// wide × 6 cells tall (one cell = 2 vertical pixels). We test against
/// that exact bounding box anchored on the agent's `character_anchor`.
pub(crate) fn hit_test_agent(
    scene: &SceneState,
    layout: &Layout,
    now: SystemTime,
    rctx: &mut pose::RouteCtx<'_>,
    mx: u16,
    my: u16,
) -> Option<AgentId> {
    // Width-in-cells (sprite is 8 px wide; we don't divide x by 2 because
    // each pixel column is one cell column in the half-block grid).
    const SPRITE_W_CELLS: u16 = 8;
    // Height-in-cells: sprite is 12 px tall = 6 cells.
    const SPRITE_H_CELLS: u16 = 6;
    for agent in scene.agents.values() {
        let Some(anchor) = character_anchor(agent, layout, now, rctx) else {
            continue;
        };
        let cell_x = anchor.x;
        let cell_y = anchor.y / 2;
        if mx >= cell_x
            && mx < cell_x.saturating_add(SPRITE_W_CELLS)
            && my >= cell_y
            && my < cell_y.saturating_add(SPRITE_H_CELLS)
        {
            return Some(agent.agent_id);
        }
    }
    None
}

/// Lightweight hit-test for click-to-pin without needing router/overlay state.
/// Uses home desk positions only (no walking agents).
pub fn hit_test_from_tui(scene: &SceneState, layout: &Layout, mx: u16, my: u16) -> Option<AgentId> {
    const SPRITE_W: u16 = 8;
    const SPRITE_H_CELLS: u16 = 6;
    for agent in scene.agents.values() {
        if agent.desk_index >= layout.home_desks.len() {
            continue;
        }
        let desk = &layout.home_desks[agent.desk_index];
        let ax = desk.x + 1;
        let ay = desk.y.saturating_sub(4);
        let cell_x = ax;
        let cell_y = ay / 2;
        if mx >= cell_x
            && mx < cell_x.saturating_add(SPRITE_W)
            && my >= cell_y
            && my < cell_y.saturating_add(SPRITE_H_CELLS)
        {
            return Some(agent.agent_id);
        }
    }
    None
}

/// Hit-test whether the mouse is over the pantry coffee machine.
/// Returns true if `(mx, my)` (terminal cell coords) falls on the coffee
/// machine section of the pantry counter sprite.
pub fn hit_test_coffee_machine(layout: &Layout, mx: u16, my: u16) -> bool {
    let pantry_wp = layout
        .waypoints
        .iter()
        .find(|w| matches!(w.kind, crate::tui::layout::WaypointKind::Pantry));
    let Some(wp) = pantry_wp else {
        return false;
    };
    let Size { w: cw, h: ch } = layout.pantry_counter_size;
    let sprite_x = wp.pos.x.saturating_sub(cw / 2);
    let sprite_y = wp.pos.y.saturating_sub(ch / 2);
    let (coffee_x0, coffee_x1) = if cw >= 32 {
        (sprite_x + 11, sprite_x + 18)
    } else {
        (sprite_x + 8, sprite_x + 13)
    };
    let coffee_y0 = sprite_y;
    let coffee_y1 = sprite_y + ch;
    let cell_y = my * 2;
    mx >= coffee_x0 && mx < coffee_x1 && cell_y >= coffee_y0 && cell_y < coffee_y1
}

/// Hit-test all furniture items in the office. Returns a short label
/// if `(mx, my)` (terminal cell coords) falls on any known item.
/// The coffee machine is handled separately for its click-to-open
/// behavior — this function covers the remaining decorations.
pub fn hit_test_furniture(layout: &Layout, mx: u16, my: u16) -> Option<&'static str> {
    use crate::tui::layout::{
        furniture_def, Furniture, PlantItem, PlantKind, PodDecor, PodDecorItem, WallDecor,
        WallDecorItem, WaypointKind, DESK_H, DESK_W, ELEVATOR_H, ELEVATOR_W,
    };
    // Hover boxes derive from the one furniture table — `.visual` (the visible
    // sprite) for what the user points at, `.footprint` where the obstacle is
    // the thing — so a geometry edit can't leave a stale hit box behind.
    let visual = |f| furniture_def(f).visual;
    let footprint = |f| furniture_def(f).footprint.unwrap_or(Size { w: 0, h: 0 });
    let px = mx;
    let py = my * 2;

    let hit = |x: u16, y: u16, w: u16, h: u16| -> bool {
        px >= x && px < x.saturating_add(w) && py >= y && py < y.saturating_add(h)
    };

    // Home desks
    for desk in &layout.home_desks {
        if hit(desk.x, desk.y, DESK_W + 2, DESK_H) {
            return Some("Desk");
        }
    }

    // Lounge couch: one 20px hover region centred on the sofa. It's 3 seat
    // waypoints now, so per-seat boxes would over-cover and multi-fire — hit
    // it once at couch_sprite_center, mirroring the single furniture paint.
    if let Some(c) = layout.couch_sprite_center {
        if hit(c.x.saturating_sub(10), c.y.saturating_sub(3), 20, 7) {
            return Some("Lounge Sofa");
        }
    }

    // Waypoints
    for wp in &layout.waypoints {
        let Size { w, h } = match wp.kind {
            // Couch hovers via the one-time region above (3 seat waypoints).
            WaypointKind::Couch => continue,
            WaypointKind::Pantry => layout.pantry_counter_size,
            // Meeting slots hover via the dedicated meeting_sofas loop below.
            WaypointKind::MeetingSofa | WaypointKind::MeetingStand => continue,
            // Footprint owned by furniture_def — same shape the mask + stand
            // point use, so the hover box can't drift from them.
            other => match furniture_def(other.furniture()).footprint {
                Some(fp) => fp,
                None => continue,
            },
        };
        let wx = wp.pos.x.saturating_sub(w / 2);
        let wy = wp.pos.y.saturating_sub(h / 2);
        if hit(wx, wy, w, h) {
            return Some(match wp.kind {
                WaypointKind::Pantry => "Pantry Counter",
                WaypointKind::PhoneBooth => "Phone Booth",
                WaypointKind::StandingDesk => "Standing Desk",
                WaypointKind::VendingMachine => "Vending Machine",
                WaypointKind::Printer => "Printer",
                // Proven unreachable today (couch + meeting slots `continue`
                // above), but this is a per-frame mouse path: skip an unexpected
                // kind rather than panic the whole TUI if a future refactor adds
                // a WaypointKind or drops one of those earlier `continue`s.
                WaypointKind::Couch | WaypointKind::MeetingSofa | WaypointKind::MeetingStand => {
                    continue
                }
            });
        }
    }

    // Meeting sofas (20px sprite, centred on the sofa point).
    for sofa in &layout.meeting_sofas {
        let Size { w, h } = visual(Furniture::MeetingSofaBody); // full 20px sprite, not the 16px footprint
        if hit(
            sofa.x.saturating_sub(w / 2),
            sofa.y.saturating_sub(h / 2),
            w,
            h,
        ) {
            return Some("Meeting Sofa");
        }
    }

    // Meeting tables
    for t in &layout.meeting_tables {
        let Size { w, h } = visual(Furniture::MeetingTable);
        if hit(t.x.saturating_sub(w / 2), t.y.saturating_sub(h / 2), w, h) {
            return Some("Meeting Table");
        }
    }

    // Pantry table
    if let Some(t) = layout.pantry_table {
        let Size { w, h } = footprint(Furniture::PantryTable);
        if hit(t.x.saturating_sub(w / 2), t.y.saturating_sub(h / 2), w, h) {
            return Some("Pantry Table");
        }
    }

    // Pantry chairs
    for chair in &layout.pantry_chairs {
        let Size { w, h } = footprint(Furniture::PantryChair); // left-biased offset 2 matches the mask stamp
        if hit(chair.x.saturating_sub(2), chair.y.saturating_sub(2), w, h) {
            return Some("Chair");
        }
    }

    // Plants
    for &PlantItem { kind, pos } in &layout.plants {
        let Size { w, h } = visual(kind.furniture()); // hover the whole visible plant, not just its ground base
        if hit(
            pos.x.saturating_sub(w / 2),
            pos.y.saturating_sub(h / 2),
            w,
            h,
        ) {
            return Some(match kind {
                PlantKind::Ficus => "Ficus",
                PlantKind::Tall => "Tall Plant",
                PlantKind::Flower => "Flower Pot",
                PlantKind::Succulent => "Succulent",
            });
        }
    }

    // Floor lamp
    if let Some(lamp) = layout.floor_lamp {
        let Size { w, h } = visual(Furniture::FloorLamp); // full 4×10 lamp sprite
        if hit(
            lamp.x.saturating_sub(w / 2),
            lamp.y.saturating_sub(h / 2),
            w,
            h,
        ) {
            return Some("Floor Lamp");
        }
    }

    // Wall decor
    for &WallDecorItem { kind, pos } in &layout.wall_decor {
        let Size { w, h } = furniture_def(kind.furniture()).visual;
        if hit(pos.x, pos.y, w, h) {
            return Some(match kind {
                WallDecor::Whiteboard => "Whiteboard",
                WallDecor::Bookshelf => "Bookshelf",
                WallDecor::BulletinBoard => "Bulletin Board",
                WallDecor::ExitSign => "Exit Sign",
                WallDecor::MeetingScreen => "Meeting Screen",
            });
        }
    }

    // Pod decor (aisle items)
    for &PodDecorItem { kind, pos } in &layout.pod_decor {
        let Size { w, h } = furniture_def(kind.furniture()).visual;
        if hit(
            pos.x.saturating_sub(w / 2),
            pos.y.saturating_sub(h / 2),
            w,
            h,
        ) {
            return Some(match kind {
                PodDecor::PlantTall => "Tall Plant",
                PodDecor::Whiteboard => "Whiteboard",
                PodDecor::Tv => "TV Stand",
                PodDecor::PhoneBooth => "Phone Booth",
                PodDecor::StandingDesk => "Standing Desk",
            });
        }
    }

    // Lounge side table
    if let Some(t) = layout.lounge_side_table {
        if hit(t.x.saturating_sub(3), t.y.saturating_sub(2), 7, 4) {
            return Some("Side Table");
        }
    }

    // Meeting room procedural items (coat rack, doormat)
    if let Some(mr) = layout.meeting_room {
        if mr.width > 20 {
            let cx = mr.x + mr.width - 5;
            let cy = mr.y + mr.height / 2 - 4;
            if hit(cx.saturating_sub(2), cy, 5, 8) {
                return Some("Coat Rack");
            }
        }
        if mr.width > 10 {
            let mat_x = mr.x + mr.width + 1;
            let mat_y = mr.y + mr.height / 2 - 2;
            if hit(mat_x, mat_y, 4, 5) {
                return Some("Doormat");
            }
        }
    }

    // Pantry room procedural items (water cooler, trash bin)
    if let Some(pr) = layout.pantry_room {
        if pr.height > 25 && pr.width > 12 {
            let wx = pr.x + pr.width - 6;
            let wy = pr.y + 8;
            if hit(wx, wy, 3, 6) {
                return Some("Water Cooler");
            }
        }
        if pr.height > 20 {
            let tx = pr.x + 3;
            let ty = pr.y + pr.height - 14;
            if hit(tx, ty, 4, 5) {
                return Some("Trash Bin");
            }
        }
    }

    // Door / elevator
    if let Some(d) = layout.door {
        if hit(d.x, d.y, ELEVATOR_W, ELEVATOR_H) {
            return Some("Elevator");
        }
    }

    None
}

/// Hit-test whether the mouse is over the office pet.
/// `pet_pos` is the pet's center anchor in pixel coordinates.
/// `kind` selects the species; `anim_name` selects the bounding box size
/// via `PetKind::hitbox`.
///
/// Returns true if `(mx, my)` (terminal cell coords) falls inside
/// the sprite's footprint.
pub fn hit_test_pet(
    kind: PetKind,
    pet_pos: crate::tui::layout::Point,
    anim_name: &str,
    mx: u16,
    my: u16,
) -> bool {
    let Size { w, h } = kind.hitbox(anim_name);
    let tl_x = pet_pos.x.saturating_sub(w / 2);
    let tl_y = pet_pos.y.saturating_sub(h / 2);
    let cell_y = my * 2;
    mx >= tl_x && mx < tl_x.saturating_add(w) && cell_y >= tl_y && cell_y < tl_y.saturating_add(h)
}

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

    #[test]
    fn coffee_machine_hit_test_returns_false_for_origin() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        assert!(!hit_test_coffee_machine(&layout, 0, 0));
    }

    #[test]
    fn coffee_machine_hit_test_returns_true_for_machine_area() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        let pantry_wp = layout
            .waypoints
            .iter()
            .find(|w| w.kind == crate::tui::layout::WaypointKind::Pantry)
            .expect("pantry");
        let Size { w: cw, h: ch } = layout.pantry_counter_size;
        let sprite_x = pantry_wp.pos.x.saturating_sub(cw / 2);
        let sprite_y = pantry_wp.pos.y.saturating_sub(ch / 2);
        let mid_x = if cw >= 32 {
            sprite_x + 14
        } else {
            sprite_x + 10
        };
        let mid_cell_y = (sprite_y + ch / 2) / 2;
        assert!(
            hit_test_coffee_machine(&layout, mid_x, mid_cell_y),
            "expected hit at coffee machine area ({mid_x}, {mid_cell_y})"
        );
    }

    #[test]
    fn furniture_hit_test_returns_none_for_empty_space() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        // Open floor must report no furniture. Scan for an empty cell rather
        // than hardcoding one — which mid-floor cells are open shifts when the
        // pod aisle spacing is retuned (a hardcoded point goes stale and lands
        // on a reflowed desk). If hit_test_furniture wrongly matched
        // everywhere, no empty cell would be found and `.expect` would panic.
        let empty = (0..(layout.buf_h / 2))
            .flat_map(|cy| (0..layout.buf_w).map(move |cx| (cx, cy)))
            .find(|&(cx, cy)| hit_test_furniture(&layout, cx, cy).is_none())
            .expect("some open-floor cell must report no furniture");
        assert_eq!(hit_test_furniture(&layout, empty.0, empty.1), None);
    }

    #[test]
    fn furniture_hit_test_finds_desk() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        let desk = layout.home_desks.first().expect("desk");
        let cell_y = (desk.y + 2) / 2;
        assert_eq!(
            hit_test_furniture(&layout, desk.x + 2, cell_y),
            Some("Desk")
        );
    }

    #[test]
    fn furniture_hit_test_finds_elevator() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        let door = layout.door.expect("door");
        let cell_y = (door.y + 7) / 2;
        assert_eq!(
            hit_test_furniture(&layout, door.x + 8, cell_y),
            Some("Elevator")
        );
    }

    #[test]
    fn furniture_hit_test_finds_meeting_table() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        let table = layout.meeting_tables.first().expect("table");
        let cell_y = table.y / 2;
        assert_eq!(
            hit_test_furniture(&layout, table.x, cell_y),
            Some("Meeting Table")
        );
    }

    #[test]
    fn furniture_hit_test_respects_floor_seed() {
        // seed=1 → Lounge variant (no meeting room)
        let layout1 = Layout::compute_with_seed(160, 200, 4, 1).expect("layout");
        assert!(layout1.meeting_tables.is_empty());
        let layout0 = Layout::compute(160, 200, 4).expect("layout");
        if let Some(table) = layout0.meeting_tables.first() {
            let cell_y = table.y / 2;
            assert_ne!(
                hit_test_furniture(&layout1, table.x, cell_y),
                Some("Meeting Table"),
            );
        }
    }

    #[test]
    fn cat_hit_test_inside_sit_sprite() {
        use crate::tui::layout::Point;
        // cat_sit is 6x6. Center at (50, 80).
        // Top-left pixel: (50-3, 80-3) = (47, 77).
        // cell_y for my=39 → 78, which is inside [77..83).
        // mx=50 inside [47..53).
        let pos = Point { x: 50, y: 80 };
        assert!(hit_test_pet(PetKind::Cat, pos, "cat_sit", 50, 39));
    }

    #[test]
    fn cat_hit_test_outside_returns_false() {
        use crate::tui::layout::Point;
        let pos = Point { x: 50, y: 80 };
        // Way outside the 6x6 sprite.
        assert!(!hit_test_pet(PetKind::Cat, pos, "cat_sit", 10, 10));
    }

    // --- hit_test_from_tui (click-to-pin, home-desk-only) -----------------

    fn scene_with_agent_at_desk(desk_index: usize) -> (SceneState, AgentId) {
        use pixtuoid_core::state::{ActivityState, AgentSlot};
        use std::path::Path;
        use std::sync::Arc;
        let id = AgentId::from_transcript_path("/pin/0.jsonl");
        let slot = AgentSlot {
            agent_id: id,
            source: Arc::from("cc"),
            session_id: Arc::from("s"),
            cwd: Arc::from(Path::new("/repo")),
            label: Arc::from("a"),
            state: ActivityState::Idle,
            state_started_at: SystemTime::UNIX_EPOCH,
            created_at: SystemTime::UNIX_EPOCH,
            last_event_at: SystemTime::UNIX_EPOCH,
            exiting_at: None,
            pending_idle_at: None,
            desk_index,
            floor_idx: 0,
            tool_call_count: 0,
            active_ms: 0,
            unknown_cwd: false,
            parent_id: None,
        };
        let mut scene = SceneState::uniform(16);
        scene.agents.insert(id, slot);
        (scene, id)
    }

    #[test]
    fn from_tui_hits_agent_at_its_desk_anchor() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        let (scene, id) = scene_with_agent_at_desk(0);
        let d = layout.home_desks[0];
        // Mirror hit_test_from_tui's own anchor geometry.
        let cx = d.x + 1;
        let cy = d.y.saturating_sub(4) / 2;
        assert_eq!(hit_test_from_tui(&scene, &layout, cx, cy), Some(id));
    }

    #[test]
    fn from_tui_misses_empty_space() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        let (scene, _id) = scene_with_agent_at_desk(0);
        assert_eq!(hit_test_from_tui(&scene, &layout, 0, 0), None);
    }

    #[test]
    fn from_tui_skips_agent_with_out_of_range_desk() {
        let layout = Layout::compute(160, 200, 4).expect("layout");
        // desk_index past the layout's home-desk count ⇒ `continue` arm.
        let (scene, _id) = scene_with_agent_at_desk(layout.home_desks.len() + 100);
        // No agent occupies any cell — scan a few and confirm None everywhere.
        for &(mx, my) in &[(0u16, 0u16), (40, 20), (80, 40)] {
            assert_eq!(hit_test_from_tui(&scene, &layout, mx, my), None);
        }
    }

    // --- hit_test_furniture: kinds the compute path never emits -------------
    // compute_with_seed never produces PlantKind::Ficus or WallDecor::Bulletin
    // Board, so the harness real-layout loop can't reach those two return arms.
    // Push them into the pub Vecs of a computed layout and hit their centers.

    #[test]
    fn furniture_hit_test_ficus_via_synthetic_plant() {
        use crate::tui::layout::Point;
        let mut layout = Layout::compute(160, 200, 4).expect("layout");
        let pos = Point { x: 40, y: 40 };
        layout.plants.push(crate::tui::layout::PlantItem {
            kind: crate::tui::layout::PlantKind::Ficus,
            pos,
        });
        // Plants are center-anchored on `pos`; hover the center cell.
        assert_eq!(hit_test_furniture(&layout, pos.x, pos.y / 2), Some("Ficus"));
    }

    #[test]
    fn furniture_hit_test_bulletin_board_via_synthetic_wall_decor() {
        use crate::tui::layout::Point;
        let mut layout = Layout::compute(160, 200, 4).expect("layout");
        // Wall decor is TOP-LEFT anchored at `pos` (not centered). Place it in
        // open space so no earlier furniture arm shadows it.
        let pos = Point { x: 60, y: 30 };
        layout.wall_decor.push(crate::tui::layout::WallDecorItem {
            kind: crate::tui::layout::WallDecor::BulletinBoard,
            pos,
        });
        assert_eq!(
            hit_test_furniture(&layout, pos.x, pos.y / 2),
            Some("Bulletin Board")
        );
    }

    #[test]
    fn cat_hit_test_sleep_smaller_box() {
        use crate::tui::layout::Point;
        // cat_sleep is 6x4. Center at (50, 80).
        // Top-left: (47, 78). Bottom-right: (53, 82).
        let pos = Point { x: 50, y: 80 };
        // cell_y for my=41 → 82, which is at the boundary (82 >= 82 is false for < check).
        // Actually wait: tl_y = 80 - 2 = 78, h=4 so range is [78..82). cell_y=82 is OUT.
        assert!(!hit_test_pet(PetKind::Cat, pos, "cat_sleep", 50, 41));
        // cell_y for my=40 → 80, inside [78..82).
        assert!(hit_test_pet(PetKind::Cat, pos, "cat_sleep", 50, 40));
    }
}
