use dsl_flow::*;
use serde_json::json;

fn write_report(name: &str, dur: std::time::Duration, ok: bool) {
    use std::fs::{create_dir_all, OpenOptions};
    use std::io::Write;
    let _ = create_dir_all("target/test-reports");
    if let Ok(mut f) = OpenOptions::new().create(true).append(true).open("target/test-reports/default.jsonl") {
        let line = serde_json::json!({
            "name": name,
            "ok": ok,
            "duration_sec": dur.as_secs_f64()
        }).to_string();
        let _ = writeln!(f, "{}", line);
    }
}

#[derive(Clone)]
struct SleepNode {
    ms: u64,
    id: String,
}

#[async_trait::async_trait]
impl dsl_flow::FlowNode for SleepNode {
    fn id(&self) -> &str {
        &self.id
    }
    async fn execute(&self, ctx: &mut dsl_flow::Context, _expr: Option<&dyn dsl_flow::ExprEngine>) -> Result<dsl_flow::NodeOutput, dsl_flow::node::NodeError> {
        tokio::time::sleep(std::time::Duration::from_millis(self.ms)).await;
        ctx.set("sleep.last", json!({"slept_ms": self.ms}));
        Ok(dsl_flow::NodeOutput { id: self.id.clone(), data: json!(self.ms) })
    }
}

#[tokio::test]
async fn test_rhai_expr_set_and_get() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Rhai });
    let flow = Flow::new(sequence! {
        expr_set(ExprEngineKind::Rhai, "1 + 2 + 3", "calc.sum"),
        expr_set(ExprEngineKind::Rhai, "ctx.calc.sum * 2", "calc.double"),
    });
    let ctx = Context::new();
    let out = engine.run_stateless(&flow, ctx).await.map_err(|e| anyhow::anyhow!(e))?;
    let arr = out.data;
    // Sequence returns last child's output
    assert_eq!(arr, json!(12));
    write_report("test_rhai_expr_set_and_get", start.elapsed(), true);
    Ok(())
}

#[tokio::test]
async fn test_conditional_node_then_else() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    use std::sync::Arc;
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Rhai });
use dsl_flow::core::types::node_id;

    let then = Arc::new(expr_set(ExprEngineKind::Rhai, "42", "branch.result")) as Arc<dyn FlowNode>;
    let els = Arc::new(expr_set(ExprEngineKind::Rhai, "0", "branch.result")) as Arc<dyn FlowNode>;
    let cond = dsl_flow::Node::new(
        node_id("cond"),
        Box::new(dsl_flow::ConditionalExecutor {
            engine: ExprEngineKind::Rhai,
            condition: "false".into(),
            then_node: then.clone(),
            else_node: Some(els.clone()),
        })
    );
    let flow = Flow::new(sequence! { cond });
    let ctx = Context::new();
    let out = engine.run_stateless(&flow, ctx).await.map_err(|e| anyhow::anyhow!(e))?;
    assert_eq!(out.data, json!(0));
    write_report("test_conditional_node_then_else", start.elapsed(), true);
    Ok(())
}

#[cfg(feature = "js")]
#[tokio::test]
async fn test_js_run_code() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Js });
    let flow = Flow::new(sequence! {
        dsl_flow::js("const a = 1; const b = 2; a + b"),
    });
    let ctx = Context::new();
    let out = engine.run_stateless(&flow, ctx).await?;
    let data = out.data;
    assert_eq!(data, json!(3));
    write_report("test_js_run_code", start.elapsed(), true);
    Ok(())
}

#[cfg(feature = "rhai")]
#[tokio::test]
async fn test_rhai_run_code() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Rhai });
    let flow = Flow::new(sequence! {
        dsl_flow::rhai("let a = 1; let b = 2; a + b"),
    });
    let ctx = Context::new();
    let out = engine.run_stateless(&flow, ctx).await.map_err(|e| anyhow::anyhow!(e))?;
    let data = out.data;
    assert_eq!(data, json!(3));
    write_report("test_rhai_run_code", start.elapsed(), true);
    Ok(())
}

#[cfg(feature = "js")]
#[tokio::test]
async fn test_js_expr_and_fork_join() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Js });
    let flow = Flow::new(sequence! {
        expr_set(ExprEngineKind::Js, "({ a: 1, b: 2 })", "obj"),
        fork_join! {
            expr_set(ExprEngineKind::Js, "ctx.obj.a + ctx.obj.b", "sum"),
            expr_set(ExprEngineKind::Js, "ctx.obj.a * ctx.obj.b", "mul")
        }
    });
    let ctx = Context::new();
    let out = engine.run_stateless(&flow, ctx).await?;
    let data = out.data;
    assert!(data.is_array());
    write_report("test_js_expr_and_fork_join", start.elapsed(), true);
    Ok(())
}

#[cfg(feature = "http")]
#[tokio::test]
async fn test_http_node_with_mock() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    use httpmock::MockServer;
    use httpmock::Method::GET;

    let server = MockServer::start_async().await;
    let _m = server.mock_async(|when, then| {
        when.method(GET).path("/data");
        then.status(200)
            .header("content-type", "application/json")
            .json_body(json!({ "ok": true, "msg": "hello" }));
    }).await;

    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Rhai });
    let flow = Flow::new(sequence! {
        dsl_flow::http_get(&format!("{}/data", server.base_url()))
    });
    let ctx = Context::new();
    let out = engine.run_stateless(&flow, ctx).await.map_err(|e| anyhow::anyhow!(e))?;
    let body = out.data.get("body").unwrap().clone();
    assert_eq!(body.get("ok").unwrap(), &json!(true));
    write_report("test_http_node_with_mock", start.elapsed(), true);
    Ok(())
}

#[tokio::test]
async fn test_stateful_engine() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store.clone(), FlowOptions { stateful: true, expr_engine: ExprEngineKind::Rhai });
    let flow = Flow::new(sequence! {
        expr_set(ExprEngineKind::Rhai, "if ctx.counter == () { 0 } else { ctx.counter + 1 }", "counter")
    });
    let ctx = Context::new();
    let s = "session-1";
    let _out1 = engine.run_stateful(s, &flow, ctx.clone()).await.map_err(|e| anyhow::anyhow!(e))?;
    let out2 = engine.run_stateful(s, &flow, ctx.clone()).await.map_err(|e| anyhow::anyhow!(e))?;
    assert_eq!(out2.data, json!(1));
    write_report("test_stateful_engine", start.elapsed(), true);
    Ok(())
}

#[tokio::test]
async fn test_db_and_mq_nodes() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Rhai });
    let flow = Flow::new(sequence! {
        dsl_flow::db_node("insert_user", json!({"name": "Alice"})),
        dsl_flow::mq_node("user.events", json!({"event": "created", "user": "Alice"})),
    });
    let ctx = Context::new();
    let out = engine.run_stateless(&flow, ctx).await.map_err(|e| anyhow::anyhow!(e))?;
    assert_eq!(out.data.get("status").unwrap(), &json!("sent"));
    write_report("test_db_and_mq_nodes", start.elapsed(), true);
    Ok(())
}

#[tokio::test]
async fn test_group_parallel_sleep() -> anyhow::Result<()> {
    
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Rhai });
    let n1 = SleepNode { ms: 200, id: "sleep-200".into() };
    let n2 = SleepNode { ms: 200, id: "sleep-200b".into() };
    let group = group_merge! { "agg.group", merge_mode_array(), n1, n2 };
    let flow = Flow::new(sequence! { group });
    let ctx = Context::new();
    let start = std::time::Instant::now();
    let _ = engine.run_stateless(&flow, ctx).await.map_err(|e| anyhow::anyhow!(e))?;
    let elapsed = start.elapsed();
    assert!(elapsed.as_millis() < 380, "elapsed={}ms", elapsed.as_millis());
    write_report("test_group_parallel_sleep", start.elapsed(), true);
    Ok(())
}

#[tokio::test]
async fn test_expr_set_without_engine_error() -> anyhow::Result<()> {
    let start = std::time::Instant::now();
    let mut ctx = Context::new();
    let node = expr_set(ExprEngineKind::Rhai, "1+1", "x");
    let res = dsl_flow::FlowNode::execute(&node, &mut ctx, None).await;
    assert!(res.is_err());
    write_report("test_expr_set_without_engine_error", start.elapsed(), true);
    Ok(())
}

#[tokio::test]
async fn test_fork_join_merge_and_lineage() -> anyhow::Result<()> {
    let store = InMemoryStateStore::default();
    let engine = FlowEngine::new(store, FlowOptions { stateful: false, expr_engine: ExprEngineKind::Rhai });
    let flow = Flow::new(sequence! {
        fork_join_merge! { "agg.fork", merge_mode_object_by_id(),
            expr_set(ExprEngineKind::Rhai, "10", "a.x"),
            expr_set(ExprEngineKind::Rhai, "20", "b.y")
        },
        expr_get(ExprEngineKind::Rhai, "ctx.agg.fork")
    });
    let ctx = Context::new();
    let out = engine.run_stateless(&flow, ctx).await.map_err(|e| anyhow::anyhow!(e))?;
    let obj = out.data;
    assert!(obj.is_object());
    Ok(())
}