// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

use {
    anyhow::{format_err, Context, Error},
    fidl::endpoints,
    fidl_fuchsia_io::DirectoryMarker,
    fidl_fuchsia_sys2 as fsys,
    fidl_fuchsia_test::{
        CaseListenerRequest::Finished,
        Invocation, Result_ as TestResult,
        RunListenerRequest::{OnFinished, OnTestCaseStarted},
        RunListenerRequestStream,
    },
    fidl_fuchsia_test_manager as ftest_manager,
    fuchsia_component::client::{self, connect_to_protocol_at_dir_root},
    futures::prelude::*,
    std::collections::HashMap,
    test_executor::TestEvent,
};

#[derive(PartialEq, Debug)]
pub enum ListenerEvent {
    StartTest(String),
    FinishTest(String, TestResult),
    FinishAllTests,
}

fn get_ord_index_and_name(event: &ListenerEvent) -> (usize, &str) {
    match event {
        ListenerEvent::StartTest(name) => (0, name),
        ListenerEvent::FinishTest(name, _) => (1, name),
        ListenerEvent::FinishAllTests => (2, ""),
    }
}

// Orders by test name and then event type.
impl Ord for ListenerEvent {
    fn cmp(&self, other: &Self) -> core::cmp::Ordering {
        let (s_index, s_test_name) = get_ord_index_and_name(self);
        let (o_index, o_test_name) = get_ord_index_and_name(other);
        if s_test_name == o_test_name || s_index == 2 || o_index == 2 {
            return s_index.cmp(&o_index);
        }
        return s_test_name.cmp(&o_test_name);
    }
}

// Makes sure that FinishTest event never shows up before StartTest and FinishAllTests is always
// last.
pub fn assert_event_ord(events: &Vec<ListenerEvent>) {
    let mut tests = HashMap::new();
    let mut all_finish = false;
    for event in events {
        assert!(!all_finish, "got FinishAllTests event twice: {:#?}", events);
        match event {
            ListenerEvent::StartTest(name) => {
                assert!(
                    !tests.contains_key(&name),
                    "Multiple StartTest for test {}: {:#?}",
                    name,
                    events
                );
                tests.insert(name, false);
            }
            ListenerEvent::FinishTest(name, _) => {
                assert!(
                    tests.contains_key(&name),
                    "Got finish before start event for test {}: {:#?}",
                    name,
                    events
                );
                assert!(
                    !tests.insert(name, true).unwrap(),
                    "Multiple FinishTest for test {}: {:#?}",
                    name,
                    events
                );
            }
            ListenerEvent::FinishAllTests => {
                all_finish = true;
            }
        }
    }
}

impl PartialOrd for ListenerEvent {
    fn partial_cmp(&self, other: &ListenerEvent) -> Option<core::cmp::Ordering> {
        Some(self.cmp(other))
    }
}

impl Eq for ListenerEvent {}

impl ListenerEvent {
    pub fn start_test(name: &str) -> ListenerEvent {
        ListenerEvent::StartTest(name.to_string())
    }
    pub fn finish_test(name: &str, test_result: TestResult) -> ListenerEvent {
        ListenerEvent::FinishTest(name.to_string(), test_result)
    }
    pub fn finish_all_test() -> ListenerEvent {
        ListenerEvent::FinishAllTests
    }
}

impl Clone for ListenerEvent {
    fn clone(&self) -> Self {
        match self {
            ListenerEvent::StartTest(name) => ListenerEvent::start_test(name),
            ListenerEvent::FinishTest(name, test_result) => ListenerEvent::finish_test(
                name,
                TestResult { status: test_result.status.clone(), ..TestResult::EMPTY },
            ),
            ListenerEvent::FinishAllTests => ListenerEvent::finish_all_test(),
        }
    }
}

/// Collects all the listener event as they come and return in a vector.
pub async fn collect_listener_event(
    mut listener: RunListenerRequestStream,
) -> Result<Vec<ListenerEvent>, Error> {
    let mut ret = vec![];
    // collect loggers so that they do not die.
    let mut loggers = vec![];
    while let Some(result_event) = listener.try_next().await? {
        match result_event {
            OnTestCaseStarted { invocation, primary_log, listener, .. } => {
                let name = invocation.name.unwrap();
                ret.push(ListenerEvent::StartTest(name.clone()));
                loggers.push(primary_log);
                let mut listener = listener.into_stream()?;
                while let Some(result) = listener.try_next().await? {
                    match result {
                        Finished { result, .. } => {
                            ret.push(ListenerEvent::FinishTest(name, result));
                            break;
                        }
                    }
                }
            }
            OnFinished { .. } => {
                ret.push(ListenerEvent::FinishAllTests);
                break;
            }
        }
    }
    Ok(ret)
}

/// Helper method to convert names to `Invocation`.
pub fn names_to_invocation(names: Vec<&str>) -> Vec<Invocation> {
    names
        .iter()
        .map(|s| Invocation { name: Some(s.to_string()), tag: None, ..Invocation::EMPTY })
        .collect()
}

// process events by parsing and normalizing logs
pub fn process_events(events: Vec<TestEvent>, exclude_empty_logs: bool) -> Vec<TestEvent> {
    let mut test_events = vec![];
    // map to buffer incomplete logs(that did not end in newline) by test case.
    let mut buffered_logs = HashMap::new();
    // break logs as they can be grouped in any way.
    for event in events {
        match event {
            TestEvent::StdoutMessage { test_case_name, msg } => {
                let logs = msg.split("\n");
                let mut logs = logs.collect::<Vec<&str>>();
                // discard last empty log(if it ended in newline, or  store im-complete line)
                let mut last_incomplete_line = logs.pop();
                if msg.as_bytes().last() == Some(&b'\n') {
                    last_incomplete_line = None;
                }

                for log in logs {
                    if exclude_empty_logs && log.len() == 0 {
                        continue;
                    }
                    let mut msg = log.to_owned();
                    // This is only executed for first log line and used to concat previous
                    // buffered line.
                    if let Some(prev_log) = buffered_logs.remove(&test_case_name) {
                        msg = format!("{}{}", prev_log, msg);
                    }
                    test_events.push(TestEvent::StdoutMessage {
                        test_case_name: test_case_name.clone(),
                        msg: msg,
                    });
                }
                if let Some(log) = last_incomplete_line {
                    let mut log = log.to_owned();
                    if let Some(prev_log) = buffered_logs.remove(&test_case_name) {
                        log = format!("{}{}", prev_log, log);
                    }
                    buffered_logs.insert(test_case_name.clone(), log);
                }
            }
            event => {
                test_events.push(event);
            }
        };
    }

    for (test_case_name, log) in buffered_logs {
        test_events.push(TestEvent::StdoutMessage { test_case_name: test_case_name, msg: log });
    }

    test_events
}

// Binds to test manager component and returns the test suite serivce.
pub async fn connect_to_test_manager() -> Result<ftest_manager::HarnessProxy, Error> {
    let realm = client::connect_to_service::<fsys::RealmMarker>()
        .context("could not connect to Realm service")?;

    let mut child_ref = fsys::ChildRef { name: "test_manager".to_owned(), collection: None };
    let (dir, server_end) = endpoints::create_proxy::<DirectoryMarker>()?;
    realm
        .bind_child(&mut child_ref, server_end)
        .await
        .context("bind_child fidl call failed for test manager")?
        .map_err(|e| format_err!("failed to create test manager: {:?}", e))?;

    connect_to_protocol_at_dir_root::<ftest_manager::HarnessMarker>(&dir)
        .context("failed to open test suite service")
}

#[cfg(test)]
mod tests {
    use super::*;
    use fidl_fuchsia_test::Status;

    #[test]
    fn test_ordering_by_enum() {
        let expected_events = vec![
            ListenerEvent::start_test("a"),
            ListenerEvent::finish_test(
                "a",
                TestResult { status: Some(Status::Passed), ..TestResult::EMPTY },
            ),
            ListenerEvent::finish_all_test(),
        ];

        let mut events = expected_events.clone();
        events.reverse();

        assert_ne!(events, expected_events);
        events.sort();
        assert_eq!(events, expected_events);
    }

    #[test]
    fn test_ordering_by_test_name() {
        let mut events = vec![
            ListenerEvent::start_test("b"),
            ListenerEvent::start_test("a"),
            ListenerEvent::finish_test(
                "a",
                TestResult { status: Some(Status::Passed), ..TestResult::EMPTY },
            ),
            ListenerEvent::start_test("c"),
            ListenerEvent::finish_test(
                "b",
                TestResult { status: Some(Status::Passed), ..TestResult::EMPTY },
            ),
            ListenerEvent::finish_test(
                "c",
                TestResult { status: Some(Status::Passed), ..TestResult::EMPTY },
            ),
            ListenerEvent::finish_all_test(),
        ];

        let expected_events = vec![
            ListenerEvent::start_test("a"),
            ListenerEvent::finish_test(
                "a",
                TestResult { status: Some(Status::Passed), ..TestResult::EMPTY },
            ),
            ListenerEvent::start_test("b"),
            ListenerEvent::finish_test(
                "b",
                TestResult { status: Some(Status::Passed), ..TestResult::EMPTY },
            ),
            ListenerEvent::start_test("c"),
            ListenerEvent::finish_test(
                "c",
                TestResult { status: Some(Status::Passed), ..TestResult::EMPTY },
            ),
            ListenerEvent::finish_all_test(),
        ];
        events.sort();
        assert_eq!(events, expected_events);
    }
}