"""CLI 入口: 简单 REPL。

用法:
    python cli.py chat                       # 新建一个 session
    python cli.py chat --resume last         # 恢复最近一个
    python cli.py chat --resume 20260506_141523
    python cli.py chat --model deepseek_v4.pro
    python cli.py sessions                   # 列出历史 session
"""
from __future__ import annotations

import json
import sys
from pathlib import Path

import click
from rich.console import Console
from rich.prompt import Prompt

from main import build_agent, load_config, resolve_workspace, sessions_dir


@click.group()
def cli() -> None:
    """zcbot - 个人任务 agent"""


@cli.command()
@click.option("--model", default=None, help="模型档案,如 deepseek_v4.flash 或 deepseek_v4.pro")
@click.option("--workspace", default=None, help="工作目录(存 sessions/)")
@click.option("--resume", default=None, help="恢复某个 session: 'last' 或 session_id")
def chat(model: str, workspace: str, resume: str) -> None:
    """启动交互式 REPL。每次启动默认开新 session,用 --resume 接老的。"""
    console = Console()
    try:
        agent, session, sid = build_agent(
            model_name=model,
            workspace=workspace,
            console=console,
            session_id=resume,
            resume=bool(resume),
        )
    except Exception as e:
        console.print(f"[red]启动失败:[/red] {type(e).__name__}: {e}")
        sys.exit(1)

    if resume:
        console.print(
            f"[green]恢复 session[/green] [bold]{sid}[/bold] ({len(session.messages)} 条消息) "
            f"model: [bold]{agent.caps.model_id}[/bold]"
        )
    else:
        console.print(
            f"[green]新 session[/green] [bold]{sid}[/bold] "
            f"model: [bold]{agent.caps.model_id}[/bold]"
        )
    console.print("[dim]/exit 退出  /reset 清空当前对话  /new 开一个新 session  /id 显示 session id[/dim]\n")

    while True:
        try:
            user_input = Prompt.ask("[bold blue]you[/bold blue]")
        except (EOFError, KeyboardInterrupt):
            console.print("\n[dim]bye[/dim]")
            break

        cmd = user_input.strip()
        if cmd in ("/exit", "/quit"):
            break
        if cmd == "/reset":
            session.reset(keep_system=True)
            console.print("[dim]当前 session 已重置(保留 system)[/dim]")
            continue
        if cmd == "/new":
            try:
                agent, session, sid = build_agent(
                    model_name=model, workspace=workspace, console=console
                )
            except Exception as e:
                console.print(f"[red]新建失败:[/red] {type(e).__name__}: {e}")
                continue
            console.print(f"[green]新 session[/green] [bold]{sid}[/bold]")
            continue
        if cmd == "/id":
            cwd_disp = session.meta.get("cwd", "?")
            model_disp = session.meta.get("model", agent.caps.model_id)
            console.print(f"[dim]session: {sid}  model: {model_disp}  cwd: {cwd_disp}[/dim]")
            continue
        if not cmd:
            continue

        try:
            agent.run(user_input)
        except KeyboardInterrupt:
            console.print("\n[yellow]已中断本轮。下一条输入会继续这个 session。[/yellow]")
        except Exception as e:
            console.print(f"[red]运行错误:[/red] {type(e).__name__}: {e}")


@cli.command()
@click.option("--workspace", default=None, help="工作目录")
@click.option("--limit", default=20, help="显示最近 N 个")
def sessions(workspace: str, limit: int) -> None:
    """列出已有 session。"""
    cfg = load_config()
    ws = resolve_workspace(workspace, cfg)
    sdir = sessions_dir(ws)

    items = sorted(sdir.glob("*.json"), reverse=True)[:limit]
    if not items:
        click.echo(f"(no sessions in {sdir})")
        return

    click.echo(f"{'session id':<18}  {'msgs':>4}  {'cwd':<32}  preview")
    click.echo("-" * 100)
    for p in items:
        try:
            data = json.loads(p.read_text(encoding="utf-8"))
            if isinstance(data, list):
                messages, meta = data, {}
            else:
                messages = data.get("messages", []) or []
                meta = data.get("meta", {}) or {}
            n = len(messages)
            preview = ""
            for m in messages:
                if isinstance(m, dict) and m.get("role") == "user":
                    preview = (m.get("content") or "")[:50].replace("\n", " ")
                    break
            cwd = meta.get("cwd") or "?"
            if len(cwd) > 32:
                cwd = "..." + cwd[-29:]
        except Exception as e:
            n, preview, cwd = -1, f"[parse error: {e}]", "?"
        click.echo(f"{p.stem:<18}  {n:>4}  {cwd:<32}  {preview}")


if __name__ == "__main__":
    cli()