//! 出站帧保留 JSON 原文，并在写出长度前验证合并后的预算。
use super::*;
use crate::wire::json::Json;
use std::{hint::black_box, process::Stdio, time::Instant};

#[derive(serde::Serialize)]
struct Call<'input> {
    kind: &'static str,
    id: u64,
    operation: &'input str,
}

#[test]
fn outgoing_payload_preserves_spelling_and_combined_limits() {
    let header = Call {
        kind: "call",
        id: 1,
        operation: "雪\"\\",
    };
    for source in ["null", " \n{\"雪\":[1e9999,-0,\"\\u96ea\"]}\t "] {
        let value = Json::parse(source).unwrap();
        let head = payload_header(
            serde_json::to_string(&header).unwrap(),
            4,
            ",\"payload\":",
            value.shape().unwrap(),
        )
        .unwrap();
        let frame = format!("{head}{}}}", source.trim_ascii());
        #[derive(serde::Serialize)]
        struct Reference<'input> {
            #[serde(flatten)]
            header: &'input Call<'input>,
            payload: &'input RawValue,
        }
        assert_eq!(
            frame,
            serde_json::to_string(&Reference {
                header: &header,
                payload: serde_json::from_str(source).unwrap(),
            })
            .unwrap()
        );
        crate::wire::raw::validate(&frame).unwrap();
    }
    for count in [document::MAX_VALUES - 5, document::MAX_VALUES - 4] {
        let value = Json::encode(&vec![0; count]).unwrap();
        let encoded = payload_header(
            serde_json::to_string(&header).unwrap(),
            4,
            ",\"payload\":",
            value.shape().unwrap(),
        );
        assert_eq!(encoded.is_ok(), count == document::MAX_VALUES - 5);
    }
    for depth in [document::MAX_DEPTH - 1, document::MAX_DEPTH] {
        let value = Json::parse(&("[".repeat(depth) + &"]".repeat(depth))).unwrap();
        assert_eq!(
            payload_header(
                serde_json::to_string(&header).unwrap(),
                4,
                ",\"payload\":",
                value.shape().unwrap()
            )
            .is_ok(),
            depth < document::MAX_DEPTH
        );
    }
}

#[test]
fn oversized_frame_does_not_write_a_partial_prefix() {
    let runtime = tokio::runtime::Builder::new_current_thread()
        .enable_all()
        .build()
        .unwrap();
    runtime.block_on(async {
        let mut child = tokio::process::Command::new("cat")
            .stdin(Stdio::piped())
            .stdout(Stdio::piped())
            .spawn()
            .unwrap();
        let mut channel = Channel::new(child.stdin.take().unwrap(), child.stdout.take().unwrap());
        let payload = Json::string(&"a".repeat(LIMIT - 2)).unwrap();
        let header = Call {
            kind: "call",
            id: 1,
            operation: "measure",
        };
        assert!(
            channel
                .send_payload(
                    serde_json::to_string(&header).unwrap(),
                    4,
                    ",\"payload\":",
                    payload.as_str(),
                    payload.shape().unwrap()
                )
                .await
                .is_err()
        );
        let control = serde_json::json!({"kind":"health","id":0});
        channel.send(&control).await.unwrap();
        assert_eq!(channel.read().await.unwrap().as_str(), control.to_string());
        drop(channel);
        assert!(child.wait().await.unwrap().success());
    });
}

fn reference_header(header: &Call<'_>, values: usize, depth: usize) -> Result<String, String> {
    if values + 4 > document::MAX_VALUES || depth + 1 > document::MAX_DEPTH {
        return Err("JSON budget".into());
    }
    let mut text = serde_json::to_string(header).map_err(|error| error.to_string())?;
    // 与正式通道一样，整帧字节预算在写出长度前检查，不属于帧头编码计时。
    text.pop();
    text.push_str(",\"payload\":");
    Ok(text)
}

#[test]
#[ignore = "explicit release performance probe; header only, not complete IPC"]
fn outgoing_header_cost() {
    let header = Call {
        kind: "call",
        id: 42,
        operation: "measure",
    };
    let shape = document::Shape::new(2, 1);
    let expected = reference_header(&header, 2, 1).unwrap();
    assert_eq!(
        payload_header(
            serde_json::to_string(&header).unwrap(),
            4,
            ",\"payload\":",
            shape
        )
        .unwrap(),
        expected
    );
    for sample in 0..15 {
        for native in if sample % 2 == 0 {
            [false, true]
        } else {
            [true, false]
        } {
            let started = Instant::now();
            let mut checksum = 0;
            for _ in 0..100_000 {
                let text = if native {
                    reference_header(black_box(&header), black_box(2), black_box(1))
                } else {
                    payload_header(
                        serde_json::to_string(black_box(&header)).unwrap(),
                        4,
                        ",\"payload\":",
                        black_box(shape),
                    )
                }
                .unwrap();
                checksum += black_box(text).len();
            }
            assert_eq!(checksum, 100_000 * expected.len());
            println!(
                "worker_header,{sample},{},{},{checksum}",
                if native { "rust" } else { "dever" },
                started.elapsed().as_nanos()
            );
        }
    }
}