//! A fresh world's seeded init service serves chat and proxies the real harness API.
use sausage::{
    cred::{
        Caller, Cred,
        items::{Item, Rule},
        requests::GrantRequest,
    },
    harness::{
        input::{self, Input},
        run_module_with_input,
    },
    process::Runtime,
    world::World,
};
use std::{path::Path, sync::Arc, time::Duration};
use tokio::io::{AsyncReadExt, AsyncWriteExt};

async fn request(port: u16, path: &str, body: Option<&str>) -> anyhow::Result<(u16, Vec<u8>)> {
    let mut stream = tokio::net::TcpStream::connect(("127.0.0.1", port)).await?;
    let method = if body.is_some() { "POST" } else { "GET" };
    let body = body.unwrap_or("");
    stream.write_all(format!("{method} {path} HTTP/1.1\r\nHost: localhost\r\nContent-Type: application/json\r\nContent-Length: {}\r\nConnection: close\r\n\r\n{body}",body.len()).as_bytes()).await?;
    let mut bytes = Vec::new();
    stream.read_to_end(&mut bytes).await?;
    let end = bytes
        .windows(4)
        .position(|s| s == b"\r\n\r\n")
        .ok_or_else(|| anyhow::anyhow!("Missing HTTP headers"))?
        + 4;
    let header = std::str::from_utf8(&bytes[..end])?;
    let status = header.split_whitespace().nth(1).unwrap().parse()?;
    Ok((status, bytes[end..].to_vec()))
}
#[test]
fn page_rendering() -> anyhow::Result<()> {
    let source = Path::new(env!("CARGO_MANIFEST_DIR")).join("../userland/chat");
    let page = std::fs::read_to_string(source.join("index.html"))?;
    let script = page
        .split_once("<script>")
        .unwrap()
        .1
        .split_once("</script>")
        .unwrap()
        .0;
    let dir = tempfile::tempdir()?;
    let extracted = dir.path().join("chat.js");
    std::fs::write(&extracted, script)?;
    let fixture = source.join("render.test.cjs");
    for args in [
        [Path::new("--check"), extracted.as_path()],
        [fixture.as_path(), extracted.as_path()],
    ] {
        let output = std::process::Command::new("node").args(args).output()?;
        anyhow::ensure!(
            output.status.success(),
            "Page script: {}",
            String::from_utf8_lossy(&output.stderr)
        );
    }
    Ok(())
}

#[tokio::test(flavor = "current_thread")]
async fn seeded_chat() -> anyhow::Result<()> {
    seeded_chat_case(false).await
}
#[tokio::test(flavor = "current_thread")]
async fn shutdown_with_open_connection() -> anyhow::Result<()> {
    seeded_chat_case(true).await
}
async fn seeded_chat_case(open_connection: bool) -> anyhow::Result<()> {
    let source = Path::new(env!("CARGO_MANIFEST_DIR")).join("..");
    let target = crate::common::target_dir();
    crate::common::cwd_init();
    anyhow::ensure!(
        std::process::Command::new("cargo")
            .args([
                "build",
                "--release",
                "--locked",
                "-p",
                "sausage-chat",
                "-p",
                "sausage-init",
                "--target",
                "wasm32-wasip2",
                "--target-dir"
            ])
            .arg(&target)
            .current_dir(source.join("userland"))
            .status()?
            .success(),
        "Chat guest build failed"
    );
    let bundle = tempfile::tempdir()?;
    let units = bundle.path().join("etc/systemd/system");
    std::fs::create_dir_all(units.join("multi-user.target.wants"))?;
    std::fs::copy(
        source.join("userland/chat/chat.service"),
        units.join("chat.service"),
    )?;
    std::fs::write(units.join("multi-user.target.wants/chat.service"), "")?;
    std::fs::create_dir_all(bundle.path().join("bin"))?;
    for binary in ["chat", "init"] {
        std::fs::copy(
            target.join(format!("wasm32-wasip2/release/{binary}.wasm")),
            bundle.path().join(format!("bin/{binary}.wasm")),
        )?;
    }
    crate::common::copy_tree(
        &source.join("userland/chat"),
        &bundle.path().join("src/sausage/userland/chat"),
    )?;
    let dir = tempfile::tempdir()?;
    drop(World::open_with_userland(dir.path(), Some(bundle.path()))?);
    let port = std::net::TcpListener::bind("127.0.0.1:0")?
        .local_addr()?
        .port();
    let seeded = dir.path().join("world/etc/systemd/system/chat.service");
    let unit = std::fs::read_to_string(&seeded)?.replace(
        "ExecStart=/bin/chat.wasm",
        &format!("ExecStart=/bin/chat.wasm --listen 127.0.0.1:{port}"),
    );
    std::fs::write(&seeded, &unit)?;
    let world = World::open_with_userland(dir.path(), Some(bundle.path()))?;
    assert_eq!(
        std::fs::read_to_string(&seeded)?,
        unit,
        "Reopen must not replace a world's unit"
    );
    assert!(
        dir.path()
            .join("world/src/sausage/userland/chat/Cargo.toml")
            .is_file()
    );
    let cred = Arc::new(Cred::open(&world.host_dir)?);
    let caller = Caller {
        program: "/bin/chat.wasm".into(),
        pid: 1,
        conversations: vec!["1".into()],
    };
    let item = cred.create_item(
        Item {
            id: String::new(),
            name: "Chat test credential".into(),
            version: 0,
            free_use: false,
            rules: vec![Rule {
                port: None,
                scheme: "https".into(),
                hosts: vec!["example.test".into()],
                path_prefixes: vec!["/".into()],
                methods: None,
            }],
            validate_js: None,
            transform_js: String::new(),
            fields: vec![],
        },
        &caller,
        cred.unlocked()?,
    )?;
    let pending = cred.file_request(
        &caller,
        "chat-test",
        GrantRequest {
            items: vec![item.id],
            duration_secs: None,
            max_uses: None,
            validator: None,
        },
    )?;
    let api = Arc::new(sausage::api::Api::open(
        cred.clone(),
        &world.host_dir,
        "localhost",
        "http://localhost:8090",
    )?);
    let (sender, receiver) = input::channel();
    api.attach_harness(sender.clone());
    let runtime = Runtime::new_with_hooks(
        World {
            root: world.root.clone(),
            host_dir: world.host_dir.clone(),
            processes: world.processes.clone(),
        },
        cred.clone(),
        sausage::process::default_script(),
        Some(api),
    )?;
    let services = sausage::process::supervise(runtime.clone());
    let (library, _) = include_str!("../../js/harness-api-test-bundle.js")
        .split_once("// harness-api-test.ts")
        .unwrap();
    let script = format!(
        r#"{library}
        const chatModels=createModels(),chatFaux=fauxProvider({{tokensPerSecond:100000}});
        chatModels.setProvider(chatFaux.provider);chatFaux.setResponses([fauxAssistantMessage('Chat test reply')]);
        const chatRegistry=createRegistry(),chatStorage=await openStorage(globalThis.storagePath);
        const chatHarness=await Harness.open(chatStorage,{{models:chatModels,registry:chatRegistry}},BACKGROUND_CONTEXT);
        await chatHarness.root(BACKGROUND_CONTEXT,{{agent:{{model:{{provider:'faux',modelId:'faux-1'}}}}}});
        const chatApi=harnessApi(chatHarness,chatModels,{{state:()=>({{}})}},BACKGROUND_CONTEXT);
        chatHarness.resume();await serve(chatHarness,BACKGROUND_CONTEXT,undefined,chatApi);
        await chatApi.close();await chatHarness.close(BACKGROUND_CONTEXT);
    "#
    );
    let client = async {
        let deadline = std::time::Instant::now() + Duration::from_secs(60);
        let page = loop {
            if let Ok((200, body)) = request(port, "/", None).await {
                break body;
            }
            anyhow::ensure!(
                std::time::Instant::now() < deadline,
                "Init did not start chat"
            );
            tokio::task::yield_now().await;
        };
        assert!(String::from_utf8_lossy(&page).contains("Sausage chat"));
        let root = loop {
            let (status, body) = request(port, "/api/conversations", None).await?;
            let value: serde_json::Value = serde_json::from_slice(&body)?;
            if status == 200
                && let Some(id) = value["conversations"][0]["id"].as_u64()
            {
                break id;
            }
            anyhow::ensure!(
                std::time::Instant::now() < deadline,
                "Harness was not ready"
            );
            tokio::task::yield_now().await;
        };
        let submit = serde_json::json!({"content":"Chat test input","requestId":"chat-stable-id"})
            .to_string();
        for _ in 0..2 {
            assert_eq!(
                request(
                    port,
                    &format!("/api/conversations/{root}/submit"),
                    Some(&submit)
                )
                .await?
                .0,
                202
            );
        }
        loop {
            let (status, body) = request(
                port,
                &format!("/api/conversations/{root}/entries?after=0"),
                None,
            )
            .await?;
            assert_eq!(status, 200);
            if String::from_utf8_lossy(&body).contains("Chat test reply") {
                let value: serde_json::Value = serde_json::from_slice(&body)?;
                assert_eq!(
                    value["entries"]
                        .as_array()
                        .unwrap()
                        .iter()
                        .filter(|e| e["kind"] == "pi.user")
                        .count(),
                    1
                );
                break;
            }
            anyhow::ensure!(std::time::Instant::now() < deadline, "Reply did not appear");
            tokio::task::yield_now().await;
        }
        let (status, body) = request(port, "/api/credential-requests", None).await?;
        assert_eq!(status, 200);
        let value: serde_json::Value = serde_json::from_slice(&body)?;
        assert!(
            value["requests"]
                .as_array()
                .unwrap()
                .iter()
                .any(|r| r["id"] == pending
                    && r["approvalUrl"] == format!("http://localhost:8090/approve/{pending}"))
        );
        assert_eq!(request(port, "/api/unknown", None).await?.0, 404);
        sender.send(Input::Stop)?;
        Ok::<_, anyhow::Error>(())
    };
    let result = tokio::time::timeout(Duration::from_secs(90), async {
        tokio::try_join!(
            run_module_with_input(world, Arc::new(runtime.clone()), cred, receiver, &script),
            client
        )
    })
    .await;
    let connection = if open_connection {
        let mut stream = tokio::net::TcpStream::connect(("127.0.0.1", port)).await?;
        // Leave the request incomplete so the server must wait for more input.
        stream
            .write_all(b"GET / HTTP/1.1\r\nHost: localhost\r\n")
            .await?;
        Some(stream)
    } else {
        None
    };
    let started = std::time::Instant::now();
    services.shutdown().await;
    let elapsed = started.elapsed();
    drop(connection);
    result??;
    println!("Chat shutdown (open_connection={open_connection}): {elapsed:?}");
    anyhow::ensure!(
        elapsed < Duration::from_secs(3),
        "Chat delayed shutdown: {elapsed:?}"
    );
    Ok(())
}