//! OpenCADStudio COMMANDS benchmark suite (`harness = false`).
//! Currently: EXPLODE (geometry pipeline + scene apply).

#[path = "support/harness.rs"]
mod harness;

use std::hint::black_box;
use std::time::Instant;

use codec::entities::{
    Dimension, DimensionLinear, Insert, Line, LwPolyline, LwVertex, MLine,
};
use codec::tables::BlockRecord;
use codec::types::{Vector2, Vector3};
use codec::{CadDocument, EntityType, Handle};

use harness::BenchmarkRunner;
use OpenCADStudio::modules::draw::modify::explode::{
    apply_explode_replacements, explode_batch,
};
use OpenCADStudio::scene::Scene;

const BLOCK_NAME: &str = "BENCH_BLOCK";
const VERTS_PER_POLYLINE: usize = 50;
const MEMBERS_PER_BLOCK: usize = 20;

/// (lwpolylines, inserts, dimensions, mlines) — full = 2,500 compounds.
fn counts(quick: bool) -> (usize, usize, usize, usize) {
    if quick {
        (1_000, 100, 100, 50)
    } else {
        (2_000, 200, 200, 100)
    }
}

fn fixture_entities(quick: bool) -> usize {
    let (a, b, c, d) = counts(quick);
    a + b + c + d
}

/// Shared 20-member block (10 lines + 10 three-vertex polylines) registered
/// in `block_records` with `entity_handles` set — what explode_from_document
/// needs to materialize inserts.
fn add_bench_block(doc: &mut CadDocument) {
    let mut member_handles = Vec::with_capacity(MEMBERS_PER_BLOCK);
    for k in 0..MEMBERS_PER_BLOCK {
        if k % 2 == 0 {
            let mut line = Line::new();
            let x = (k / 2) as f64 * 3.0;
            line.start = Vector3::new(x, 0.0, 0.0);
            line.end = Vector3::new(x, 4.0, 0.0);
            member_handles.push(doc.add_entity(EntityType::Line(line)).unwrap());
        } else {
            let mut pl = LwPolyline::new();
            pl.vertices = vec![
                LwVertex::new(Vector2::new(0.0, (k as f64) * 0.5)),
                LwVertex::new(Vector2::new(2.0, (k as f64) * 0.5)),
                LwVertex::new(Vector2::new(2.0, (k as f64) * 0.5 + 2.0)),
            ];
            member_handles.push(doc.add_entity(EntityType::LwPolyline(pl)).unwrap());
        }
    }
    let mut block = BlockRecord::new(BLOCK_NAME);
    block.handle = doc.allocate_handle();
    block.entity_handles = member_handles;
    doc.block_records.add(block).unwrap();
}

/// Populate the document with the compound fixture; returns the handles of
/// the fixture entities (block members are NOT included).
fn push_fixture_entities(doc: &mut CadDocument, quick: bool) -> Vec<Handle> {
    let (n_pl, n_ins, n_dim, n_ml) = counts(quick);
    let mut handles = Vec::with_capacity(fixture_entities(quick));

    for i in 0..n_pl {
        let base = i as f64 * 0.01;
        let mut pl = LwPolyline::new();
        pl.vertices = (0..VERTS_PER_POLYLINE)
            .map(|k| {
                let mut v = LwVertex::new(Vector2::new(
                    base + k as f64 * 2.0,
                    (k % 5) as f64 * 0.75,
                ));
                if k % 2 == 1 {
                    v.bulge = 0.5;
                }
                v
            })
            .collect();
        handles.push(doc.add_entity(EntityType::LwPolyline(pl)).unwrap());
    }

    for i in 0..n_ins {
        let pos = Vector3::new((i % 50) as f64 * 5.0, (i / 50) as f64 * 5.0, 0.0);
        let ins = Insert::new(BLOCK_NAME, pos);
        handles.push(doc.add_entity(EntityType::Insert(ins)).unwrap());
    }

    for i in 0..n_dim {
        let x = (i % 100) as f64 * 12.0;
        let y = (i / 100) as f64 * 12.0;
        let mut d = DimensionLinear::new(
            Vector3::new(x, y, 0.0),
            Vector3::new(x + 10.0, y, 0.0),
        );
        d.definition_point = Vector3::new(x + 5.0, y + 3.0, 0.0);
        d.base.text_middle_point = Vector3::new(x + 5.0, y + 4.0, 0.0);
        handles.push(doc.add_entity(EntityType::Dimension(Dimension::Linear(d))).unwrap());
    }

    for i in 0..n_ml {
        let x = (i % 100) as f64 * 8.0;
        let y = (i / 100) as f64 * 8.0;
        let pts = [
            Vector3::new(x, y, 0.0),
            Vector3::new(x + 4.0, y, 0.0),
            Vector3::new(x + 4.0, y + 4.0, 0.0),
            Vector3::new(x + 8.0, y + 4.0, 0.0),
            Vector3::new(x + 8.0, y + 8.0, 0.0),
            Vector3::new(x + 12.0, y + 8.0, 0.0),
        ];
        handles.push(doc.add_entity(EntityType::MLine(MLine::from_points(&pts))).unwrap());
    }

    handles
}

fn median(times: &[f64]) -> f64 {
    let mut sorted = times.to_vec();
    sorted.sort_by(|a, b| a.total_cmp(b));
    let n = sorted.len();
    if n % 2 == 0 {
        (sorted[n / 2 - 1] + sorted[n / 2]) * 0.5
    } else {
        sorted[n / 2]
    }
}

/// EXPLODE geometry: time `explode_batch` over the whole fixture.
/// Document build + `items` slice construction are untimed; `black_box` on
/// the result keeps the compiler from eliding the work.
fn bench_explode_geometry(runner: &mut BenchmarkRunner) {
    let name = "explode_geometry";
    if !runner.should_run(name) {
        return;
    }
    let quick = runner.quick_mode;
    let sample_count = if quick { 3 } else { 10 };
    let entity_count = fixture_entities(quick);
    let mut times = Vec::with_capacity(sample_count);

    for _ in 0..sample_count {
        let mut doc = CadDocument::new();
        add_bench_block(&mut doc);
        let handles = push_fixture_entities(&mut doc, quick);
        let items: Vec<(Handle, &EntityType)> = handles
            .iter()
            .filter_map(|&h| doc.get_entity(h).map(|e| (h, e)))
            .collect();
        assert_eq!(items.len(), entity_count);

        let t0 = Instant::now();
        let pieces = black_box(explode_batch(&items, &doc));
        times.push(t0.elapsed().as_micros() as f64);
        assert_eq!(pieces.len(), entity_count);
        assert!(
            pieces.iter().any(|p| !p.is_empty()),
            "fixture must produce non-empty pieces — block-record/explosion path broken"
        );
    }

    let med = median(&times);
    let throughput = entity_count as f64 / (med / 1_000_000.0);
    runner.record(
        name,
        "EXPLODE geometry pipeline: explode_batch over the compound fixture",
        "us",
        times,
        Some((throughput, "entities/s")),
        None,
    );
}

/// EXPLODE apply: fresh Scene per sample (untimed), replacements computed
/// untimed, `apply_explode_replacements` timed.
fn bench_explode_scene_apply(runner: &mut BenchmarkRunner) {
    let name = "explode_scene_apply";
    if !runner.should_run(name) {
        return;
    }
    let quick = runner.quick_mode;
    let sample_count = if quick { 3 } else { 10 };
    let entity_count = fixture_entities(quick);
    let mut times = Vec::with_capacity(sample_count);
    let mut total_pieces = 0usize;

    for _ in 0..sample_count {
        let mut scene = Scene::new();
        add_bench_block(&mut scene.document);
        let handles = push_fixture_entities(&mut scene.document, quick);

        let (replacements, pieces_count) = {
            let items: Vec<(Handle, &EntityType)> = handles
                .iter()
                .filter_map(|&h| scene.document.get_entity(h).map(|e| (h, e)))
                .collect();
            let per_entity = explode_batch(&items, &scene.document);
            let reps: Vec<(Handle, Vec<EntityType>)> = handles
                .into_iter()
                .zip(per_entity)
                .filter(|(_, p)| !p.is_empty())
                .collect();
            let count = reps.iter().map(|(_, p)| p.len()).sum();
            (reps, count)
        }; // `items` borrow of scene.document ends here

        let t0 = Instant::now();
        black_box(apply_explode_replacements(&mut scene, replacements));
        times.push(t0.elapsed().as_micros() as f64);
        assert!(
            pieces_count > entity_count,
            "fixture pieces ({pieces_count}) must far exceed input count ({entity_count}) — a broken explosion path returns empty lists"
        );
        if total_pieces == 0 {
            total_pieces = pieces_count; // deterministic — capture once
        }
    }

    let med = median(&times);
    let throughput = total_pieces as f64 / (med / 1_000_000.0);
    runner.record(
        name,
        "EXPLODE apply: apply_explode_replacements (erase sources + add pieces)",
        "us",
        times,
        Some((throughput, "pieces/s")),
        None,
    );
}

fn main() {
    println!("\nInitializing OpenCADStudio Command Benchmarks...");
    let mut runner = BenchmarkRunner::new(
        format!("{:^120}", "OPENCADSTUDIO COMMAND BENCHMARK REPORT"),
        "cad_command_metrics.json",
    );
    if runner.quick_mode {
        println!("Mode: QUICK (halved fixture, 3 samples per metric)");
    } else {
        println!("Mode: FULL (2,500 compounds, 10 samples per metric)");
    }

    bench_explode_geometry(&mut runner);
    bench_explode_scene_apply(&mut runner);

    runner.finish();
}