"""
CorrectBench Web Interface
基于 Streamlit 的前端界面，集成配置选择与实时日志输出
"""

import streamlit as st
import subprocess
import threading
import queue
import time
import os
import sys

# 添加项目根目录到路径
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))

from frontend.config_loader import get_config_files, get_config_path, load_tasks_from_config
from frontend.log_capture import LogReader

# 页面配置
st.set_page_config(
    page_title="CorrectBench",
    page_icon="🛠️",
    layout="wide"
)

# 进程结束标记，用于从队列中通知主线程进程已结束
_PROCESS_DONE_MARKER = "__PROCESS_DONE__"


def run_process(log_queue: queue.Queue, stop_event: threading.Event, config_path: str):
    """后台线程运行生成进程，进程结束后向队列发送结束标记"""
    process = subprocess.Popen(
        [sys.executable, "main.py", "-c", config_path],
        stdout=subprocess.PIPE,
        stderr=subprocess.STDOUT,
        text=True,
        bufsize=1,
        cwd=os.path.dirname(os.path.abspath(__file__))
    )

    # 使用 LogReader 封装日志读取
    reader = LogReader(process, log_queue, stop_event)
    reader.start()

    # 等待进程结束，同时检测 stop_event 以支持用户主动终止
    while process.poll() is None:
        if stop_event.is_set():
            process.terminate()
            try:
                process.wait(timeout=3)
            except subprocess.TimeoutExpired:
                process.kill()
                process.wait()
            break
        time.sleep(0.1)

    # 等待日志读取线程结束，确保所有输出都已入队
    reader.join(timeout=5)

    # 向队列发送进程结束标记，通知主线程重置状态
    log_queue.put(_PROCESS_DONE_MARKER)


def main():
    # 初始化 session_state
    if "running" not in st.session_state:
        st.session_state.running = False
    if "log_queue" not in st.session_state:
        st.session_state.log_queue = queue.Queue()
    if "stop_event" not in st.session_state:
        st.session_state.stop_event = threading.Event()
    if "log_lines" not in st.session_state:
        st.session_state.log_lines = []

    # ===== 侧边栏：配置选择 =====
    with st.sidebar:
        st.header("⚙️ 配置")

        config_files = get_config_files()
        if config_files:
            default_idx = config_files.index("custom.yaml") if "custom.yaml" in config_files else 0
            selected_config = st.selectbox(
                "选择配置文件",
                config_files,
                index=default_idx,
                disabled=st.session_state.running,
            )
            config_path = get_config_path(selected_config)
        else:
            st.warning("未找到配置文件，将使用默认配置")
            config_path = "config/custom.yaml"
            selected_config = "custom.yaml"

        # 显示当前配置中的题目列表
        tasks = load_tasks_from_config(config_path)
        if tasks:
            with st.expander(f"📋 题目列表 ({len(tasks)} 个)", expanded=False):
                for t in tasks:
                    st.text(t)
        else:
            st.info("配置中未指定题目列表")

        st.markdown("---")
        st.caption(f"配置路径: `{config_path}`")

    # ===== 主区域 =====
    st.title("CorrectBench - 测试基准生成")
    st.markdown(f"当前配置: `{selected_config}`")

    col1, col2, col3 = st.columns([1, 1, 2])
    start_btn = col1.button("▶️ 开始生成", disabled=st.session_state.running, use_container_width=True)
    stop_btn = col2.button("⏹️ 停止", disabled=not st.session_state.running, use_container_width=True)

    # 运行状态指示
    if st.session_state.running:
        col3.markdown("🟢 **运行中...**")
    elif st.session_state.log_lines and st.session_state.log_lines[-1] == "[完成]":
        col3.markdown("✅ **运行完成**")
    elif st.session_state.log_lines and st.session_state.log_lines[-1] == "[已停止]":
        col3.markdown("🔴 **已停止**")

    st.markdown("---")

    # 处理开始按钮
    if start_btn and not st.session_state.running:
        st.session_state.running = True
        st.session_state.log_lines = ["正在启动..."]
        st.session_state.stop_event.clear()
        # 清空队列中可能残留的旧消息
        while not st.session_state.log_queue.empty():
            try:
                st.session_state.log_queue.get_nowait()
            except queue.Empty:
                break

        thread = threading.Thread(
            target=run_process,
            args=(st.session_state.log_queue, st.session_state.stop_event, config_path),
            daemon=True
        )
        thread.start()

    if stop_btn and st.session_state.running:
        st.session_state.stop_event.set()
        st.session_state.log_lines.append("[正在停止...]")

    # 读取日志并检测进程结束标记
    try:
        while True:
            try:
                line = st.session_state.log_queue.get_nowait()
                if line == _PROCESS_DONE_MARKER:
                    # 进程已自然结束，重置运行状态
                    st.session_state.running = False
                    st.session_state.log_lines.append("[完成]")
                else:
                    st.session_state.log_lines.append(line.rstrip("\n"))
            except queue.Empty:
                break
    except Exception:
        pass

    # 显示日志
    st.markdown("### 终端输出")
    if st.session_state.log_lines:
        st.code("\n".join(st.session_state.log_lines[-200:]), language=None)
    else:
        st.info("等待开始生成...")

    # 运行中自动刷新
    if st.session_state.running:
        time.sleep(0.3)
        st.rerun()


if __name__ == "__main__":
    main()