//! tool 模块（`Tool` trait 与注册表）的集成测试。
//! Integration tests for the tool module (`Tool` trait and registry).

use focus_core::tool::{Tool, ToolEffects, ToolRegistry, ToolResult, ToolUpdateSink};
use focus_core::CoreResult;
use focus_json::JsonValue;

#[derive(Debug)]
struct EchoTool;

impl Tool for EchoTool {
    fn name(&self) -> &str {
        "echo"
    }
    fn description(&self) -> &str {
        "echoes input"
    }
    fn parameters(&self) -> JsonValue {
        JsonValue::obj()
    }
    fn effects(&self) -> ToolEffects {
        ToolEffects::READ
    }
    fn execute(
        &self,
        _id: &str,
        args: &JsonValue,
        _on_update: Option<&ToolUpdateSink<'_>>,
    ) -> CoreResult<ToolResult> {
        let text = focus_json::to_string(args);
        Ok(ToolResult::text(text))
    }
}

#[test]
fn registry_lookup() {
    let r = ToolRegistry::with(Box::new(EchoTool));
    assert!(r.get("echo").is_some());
    assert!(r.get("nope").is_none());
    assert_eq!(r.len(), 1);
}

#[test]
fn tool_definitions_shape() {
    let r = ToolRegistry::with(Box::new(EchoTool));
    let defs = r.tool_definitions();
    let arr = match &defs {
        JsonValue::Arr(a) => a,
        _ => panic!("expected array"),
    };
    let first = &arr[0];
    assert_eq!(first.get_str("name"), Some("echo"));
    assert_eq!(first.get_str("description"), Some("echoes input"));
}

#[test]
fn read_effects_compatible() {
    assert!(ToolEffects::READ.compatible_with(ToolEffects::READ));
    // 写与读不兼容。
    // write vs read is not compatible
    assert!(!ToolEffects::WRITE.compatible_with(ToolEffects::READ));
    // 触网/开进程会阻止并行。
    // network/process block parallelism
    assert!(!ToolEffects::NETWORK.compatible_with(ToolEffects::NONE));
    assert!(!ToolEffects::PROCESS.compatible_with(ToolEffects::NONE));
}

/// 工具的增量更新（on_update）必须被 agent 转发为 ToolExecutionUpdate 事件，
/// 而不是等工具结束才一次性出现（回归：此前 agent 把 on_update 传成 None）。
/// A tool's incremental updates (on_update) must be forwarded by the agent as
/// ToolExecutionUpdate events, not appear only when the tool finishes
/// (regression: the agent used to pass None for on_update).
#[test]
fn tool_updates_stream_to_agent_events() {
    use focus_core::event::{AgentEvent, VecSink};
    use focus_core::model::ContentBlock;
    use focus_core::provider::{
        ProviderRequest, StreamEvent, StreamIterator, StreamProvider, StreamResult,
    };
    use focus_core::{Agent, AgentConfig};
    use std::sync::{Arc, Mutex};

    /// 在 execute 期间通过 on_update 推送两段增量文本的工具。
    /// A tool that pushes two incremental texts via on_update during execute.
    #[derive(Debug)]
    struct StreamingTool;
    impl Tool for StreamingTool {
        fn name(&self) -> &str {
            "stream"
        }
        fn description(&self) -> &str {
            "streams updates"
        }
        fn parameters(&self) -> JsonValue {
            JsonValue::obj()
        }
        fn effects(&self) -> ToolEffects {
            ToolEffects::READ
        }
        fn execute(
            &self,
            _id: &str,
            _args: &JsonValue,
            on_update: Option<&ToolUpdateSink<'_>>,
        ) -> CoreResult<ToolResult> {
            let cb = on_update.expect("agent must pass on_update");
            cb(focus_core::tool::ToolUpdate {
                content: vec![ContentBlock::text("line one")],
                details: JsonValue::obj(),
            });
            cb(focus_core::tool::ToolUpdate {
                content: vec![ContentBlock::text("line two")],
                details: JsonValue::obj(),
            });
            Ok(ToolResult::text("done"))
        }
    }

    /// 回放固定事件序列的 mock provider：第一段模型调用 stream 工具，
    /// 第二段给出最终文本。
    /// A mock provider replaying fixed event sequences: turn 1 calls the
    /// stream tool, turn 2 gives the final text.
    #[derive(Debug, Clone, Default)]
    struct StaticProvider {
        responses: Arc<Mutex<Vec<Vec<StreamEvent>>>>,
    }
    impl StaticProvider {
        fn tool_turn(model: &str) -> Vec<StreamEvent> {
            let mut reducer = focus_core::provider::ProviderEventReducer::new(model);
            let mut events = reducer.tool_call_start(0, "stream");
            events.extend(reducer.finalize_events());
            let message = reducer.finish().expect("final message");
            events.push(StreamEvent::Done { message });
            events
        }
        fn text_turn(model: &str) -> Vec<StreamEvent> {
            let mut reducer = focus_core::provider::ProviderEventReducer::new(model);
            let mut events = reducer.text_delta("final text");
            events.extend(reducer.finalize_events());
            let message = reducer.finish().expect("final message");
            events.push(StreamEvent::Done { message });
            events
        }
    }
    impl StreamProvider for StaticProvider {
        fn stream(&self, _request: &ProviderRequest) -> StreamResult {
            let mut queue = self.responses.lock().expect("not poisoned");
            if queue.is_empty() {
                return Err(focus_core::CoreError::Provider("mock exhausted".into()));
            }
            let events = queue.remove(0);
            Ok(Box::new(Replay { events }))
        }
    }
    struct Replay {
        events: Vec<StreamEvent>,
    }
    impl StreamIterator for Replay {
        fn next_event(&mut self) -> Option<StreamEvent> {
            if self.events.is_empty() {
                None
            } else {
                Some(self.events.remove(0))
            }
        }
    }

    let provider = StaticProvider {
        responses: Arc::new(Mutex::new(vec![
            StaticProvider::tool_turn("m"),
            StaticProvider::text_turn("m"),
        ])),
    };
    let config = AgentConfig {
        model: "m".into(),
        ..Default::default()
    };
    let tools = ToolRegistry::with(Box::new(StreamingTool));
    let mut agent = Agent::new(config, Box::new(provider), tools);
    let mut sink = VecSink::new();
    agent.prompt("go", &mut sink).expect("run failed");

    let updates: Vec<&String> = sink
        .events
        .iter()
        .filter_map(|e| match e {
            AgentEvent::ToolExecutionUpdate { partial_result, .. } => {
                partial_result.content[0].as_text().map(|t| &t.text)
            }
            _ => None,
        })
        .collect();
    assert_eq!(updates, vec!["line one", "line two"]);
}