// vtebench-driven cell path workloads. On fw13 these shell out to the
// vtebench binary (https://github.com/alacritty/vtebench) and time shop's
// consumption of the corpus. The runner spawns shop, pipes the corpus to its
// stdin (or through the PTY primary once shop-bench can drive one), and
// samples PTY-drain throughput + wl-presentation-time frame stamps.

use anyhow::{Result, bail};

use super::{Workload, WorkloadResult};

pub(crate) struct Cat;
pub(crate) struct Scrolling;
pub(crate) struct Unicode;

impl Workload for Cat {
    fn name(&self) -> &'static str {
        "vtebench-cat"
    }
    fn description(&self) -> &'static str {
        "vtebench --dat cat: raw byte throughput, hot cell path"
    }
    fn run(&self) -> Result<WorkloadResult> {
        run_vtebench("cat", &["cell_throughput_mb_s", "frame_time_p99_ms"])
    }
}

impl Workload for Scrolling {
    fn name(&self) -> &'static str {
        "vtebench-scrolling"
    }
    fn description(&self) -> &'static str {
        "vtebench --dat scrolling: scroll+render frame time"
    }
    fn run(&self) -> Result<WorkloadResult> {
        run_vtebench("scrolling", &["frame_time_p99_ms", "frame_time_p50_ms"])
    }
}

impl Workload for Unicode {
    fn name(&self) -> &'static str {
        "vtebench-unicode"
    }
    fn description(&self) -> &'static str {
        "vtebench --dat unicode: grapheme + width fast path"
    }
    fn run(&self) -> Result<WorkloadResult> {
        run_vtebench("unicode", &["cell_throughput_mb_s"])
    }
}

fn run_vtebench(_dat: &str, _metrics: &[&str]) -> Result<WorkloadResult> {
    // fw13-only wiring lives here. Steps:
    //   1. Resolve the vtebench binary (env SHOP_BENCH_VTEBENCH or PATH).
    //   2. Spawn shop under a headless-Wayland fixture (weston --backend=headless
    //      or sway --no-outputs, TBD; see docs/typed-protocol.md phase 0).
    //   3. Open a PTY, launch `vtebench --dat <_dat>` inside shop, and time
    //      the read-drain via a wrapper shell that timestamps EOF.
    //   4. Sample presentation-time timestamps from shop via a debug socket
    //      (added under `--feature bench-hooks` on the shop binary).
    //   5. Emit each name in `_metrics` as an f64.
    bail!(
        "vtebench workloads are fw13-only and not yet wired; \
         see crates/shop-bench/src/workloads/vtebench.rs for the checklist"
    )
}