#!/usr/bin/env python3
"""odysseus-logs — unified view of log files across the app.

Right now logs live in two places:
  - logs/                       app-level (compound.log, future runtime)
  - /tmp/odysseus-tmux/*.log    per-tmux-session model download/serve logs

This CLI surfaces them so you don't have to remember which directory
holds what.

    odysseus-logs list                    # every log we know about
    odysseus-logs tail NAME               # tail -f a specific log
    odysseus-logs tail NAME --lines 200   # last N lines only (no follow)
    odysseus-logs cat NAME                # print full content
    odysseus-logs clean                   # delete tmux logs older than 7 days
"""
from __future__ import annotations

import os
import sys

sys.path.insert(0, os.path.join(os.path.dirname(__file__), "_lib"))
from cli import quiet_logs, emit, fail, common_parser, run, REPO_ROOT as _REPO_ROOT

quiet_logs()

import argparse, json, subprocess, time
from datetime import datetime
from pathlib import Path


_APP_LOGS = _REPO_ROOT / "logs"
_TMUX_LOGS = Path("/tmp/odysseus-tmux")


def _enumerate() -> list[dict]:
    """Return every known log file as {name, path, bytes, modified}."""
    out = []
    for base in (_APP_LOGS, _TMUX_LOGS):
        if not base.is_dir():
            continue
        for p in sorted(base.glob("*.log")):
            try:
                st = p.stat()
            except OSError:
                continue
            out.append({
                "name": p.name,
                "path": str(p),
                "bytes": st.st_size,
                "modified": datetime.fromtimestamp(st.st_mtime).isoformat(),
            })
    out.sort(key=lambda r: r["modified"], reverse=True)
    return out


def _resolve(name: str) -> Path | None:
    """Match a log by exact filename, basename-without-extension, or
    substring. Returns the most-recently-modified match if there are
    ties."""
    if not isinstance(name, str):
        return None
    candidates = []
    for base in (_APP_LOGS, _TMUX_LOGS):
        if not base.is_dir():
            continue
        for p in base.glob("*.log"):
            if p.name == name or p.stem == name or name in p.name:
                candidates.append(p)
    if not candidates:
        return None
    candidates.sort(key=lambda p: p.stat().st_mtime, reverse=True)
    return candidates[0]


def cmd_list(args):
    emit(_enumerate(), args)


def cmd_tail(args):
    p = _resolve(args.name)
    if p is None:
        fail(f"no log matching {args.name!r}; run `odysseus-logs list`")
    if args.follow:
        # Exec tail -f so signals + buffering are native.
        os.execvp("tail", ["tail", "-n", str(args.lines), "-f", str(p)])
    # Non-follow: print last N lines + exit.
    proc = subprocess.run(["tail", "-n", str(args.lines), str(p)],
                          capture_output=True, text=True)
    sys.stdout.write(proc.stdout)
    sys.exit(proc.returncode)


def cmd_cat(args):
    p = _resolve(args.name)
    if p is None:
        fail(f"no log matching {args.name!r}")
    sys.stdout.write(p.read_text(errors="replace"))


def cmd_clean(args):
    """Delete tmux logs older than --days. Doesn't touch app logs."""
    if not _TMUX_LOGS.is_dir():
        emit({"deleted": 0, "kept": 0}, args)
        return
    cutoff = time.time() - args.days * 86400
    deleted, kept = [], 0
    for p in _TMUX_LOGS.glob("*.log"):
        try:
            if p.stat().st_mtime < cutoff:
                p.unlink()
                deleted.append(p.name)
            else:
                kept += 1
        except OSError:
            continue
    emit({"deleted": deleted, "kept": kept, "cutoff_days": args.days}, args)


def _build_parser():
    p = common_parser("odysseus-logs", "Tail / list logs across the app.")
    sub = p.add_subparsers(dest="cmd", required=True)

    pl = sub.add_parser("list", parents=p._common_parents)
    pl.set_defaults(func=cmd_list)

    pt = sub.add_parser("tail", parents=p._common_parents)
    pt.add_argument("name")
    pt.add_argument("-n", "--lines", type=int, default=80)
    pt.add_argument("-f", "--follow", action="store_true",
                    help="follow new lines (tail -f); omit for one-shot")
    pt.set_defaults(func=cmd_tail)

    pc = sub.add_parser("cat", parents=p._common_parents)
    pc.add_argument("name")
    pc.set_defaults(func=cmd_cat)

    pcl = sub.add_parser("clean", parents=p._common_parents)
    pcl.add_argument("--days", type=int, default=7,
                     help="delete tmux logs older than N days (default 7)")
    pcl.set_defaults(func=cmd_clean)

    return p


if __name__ == "__main__":
    sys.exit(run(_build_parser()))