"""skiff CLI 入口。"""

from __future__ import annotations

import argparse
import re
import subprocess
import sys
from pathlib import Path
from typing import Any

from skiff import __version__
from skiff.paths import (
    ALL_TARGETS,
    EXTERNALS_DIR,
    REGISTRY_FILE,
    SKILLS_DIR,
    SKILLS_HOME,
    TEMPLATE_DIR,
    agent_skill_dir,
    ensure_skills_home,
    resolve_targets,
)
from skiff.project import (
    add_skill_to_manifest,
    iter_manifest_skills,
    load_manifest,
    remove_skill_from_manifest,
    resolve_manifest_skill,
    save_manifest,
)
from skiff.registry import external_skill_path, load_registry, save_registry
from skiff.skills import list_owned_skills, owned_skill_path, resolve_skill_source, validate_skill_name
from skiff.symlinks import check_link, copy_template, create_link, find_repo_root, remove_link


def _print(msg: str = "") -> None:
    print(msg, file=sys.stdout)


def _err(msg: str) -> None:
    print(msg, file=sys.stderr)


def cmd_setup(args: argparse.Namespace) -> None:
    repo = Path(args.path).resolve()
    if not (repo / "skills").is_dir():
        raise SystemExit(f"不是有效的 skills 仓库（缺少 skills/）: {repo}")

    # 开发场景：仓库本身就在 ~/.skills
    if repo == SKILLS_HOME.resolve() and SKILLS_HOME.is_dir() and not SKILLS_HOME.is_symlink():
        _print(f"skills 仓库已在 ~/.skills: {repo}")
        return

    if SKILLS_HOME.is_symlink():
        current = SKILLS_HOME.resolve()
        if current == repo:
            _print(f"已关联: ~/.skills -> {repo}")
            return
        SKILLS_HOME.unlink()
    elif SKILLS_HOME.exists():
        raise SystemExit(f"~/.skills 已存在且不是软链: {SKILLS_HOME}")

    SKILLS_HOME.parent.mkdir(parents=True, exist_ok=True)
    SKILLS_HOME.symlink_to(repo)
    _print(f"已关联: ~/.skills -> {repo}")


def cmd_list(args: argparse.Namespace) -> None:
    ensure_skills_home()
    owned = list_owned_skills()
    registry = load_registry()

    _print("自研 (owned):")
    for name in owned:
        _print(f"  {name}")

    _print("\n外部 (registry):")
    if not registry:
        _print("  (无)")
    else:
        for name, entry in registry.items():
            repo = entry.get("repo", "?")
            _print(f"  {name}  ({repo})")


def _installed_links(name: str, targets: list[str], project_root: Path | None = None) -> list[tuple[str, Path, Path]]:
    skill_path, _ = resolve_skill_source(name)
    rows: list[tuple[str, Path, Path]] = []
    for target in targets:
        link = agent_skill_dir(target, project_root=project_root) / name
        rows.append((target, link, skill_path))
    return rows


def cmd_status(args: argparse.Namespace) -> None:
    ensure_skills_home()
    targets = resolve_targets(args.target)
    owned = list_owned_skills()
    registry = load_registry()
    all_names = owned + [n for n in registry if n not in owned]

    _print(f"skills 仓库: {SKILLS_HOME.resolve()}")
    _print(f"targets: {', '.join(targets)}\n")

    for name in all_names:
        kind = "owned" if name in owned else "external"
        _print(f"[{kind}] {name}")
        try:
            rows = _installed_links(name, targets)
        except SystemExit:
            _print("  (未 fetch)")
            continue
        for target, link, expected in rows:
            status = check_link(link, expected)
            mark = "✓" if status.ok else "✗"
            detail = "" if status.ok else f" — {status.issue}"
            _print(f"  {mark} {target}: {link}{detail}")
        _print("")


def _install_skill(name: str, targets: list[str], project_root: Path | None = None) -> None:
    skill_path, kind = resolve_skill_source(name)
    for target in targets:
        link = agent_skill_dir(target, project_root=project_root) / name
        create_link(link, skill_path)
        scope = "项目" if project_root else "全局"
        _print(f"已安装 ({scope}/{target}): {name} -> {skill_path}")


def cmd_install(args: argparse.Namespace) -> None:
    ensure_skills_home()
    validate_skill_name(args.name)
    targets = resolve_targets(args.target)
    _install_skill(args.name, targets)


def cmd_uninstall(args: argparse.Namespace) -> None:
    ensure_skills_home()
    targets = resolve_targets(args.target)
    for target in targets:
        link = agent_skill_dir(target) / args.name
        if remove_link(link):
            _print(f"已移除 ({target}): {link}")


def cmd_add(args: argparse.Namespace) -> None:
    ensure_skills_home()
    validate_skill_name(args.name)
    registry = load_registry()
    if args.name in registry:
        raise SystemExit(f"registry 中已存在: {args.name}")

    registry[args.name] = {
        "repo": args.repo,
        "ref": args.ref,
        "path": args.path,
    }
    save_registry(registry)
    _print(f"已添加 registry 条目: {args.name}")


def cmd_fetch(args: argparse.Namespace) -> None:
    ensure_skills_home()
    registry = load_registry()
    if args.name not in registry:
        raise SystemExit(f"registry 中不存在: {args.name}")

    entry = registry[args.name]
    repo = entry["repo"]
    ref = entry.get("ref", "main")
    dest = EXTERNALS_DIR / args.name

    EXTERNALS_DIR.mkdir(parents=True, exist_ok=True)

    if dest.exists():
        _print(f"更新: {dest}")
        subprocess.run(["git", "-C", str(dest), "fetch", "--all", "--tags"], check=True)
        subprocess.run(["git", "-C", str(dest), "checkout", ref], check=True)
        subprocess.run(["git", "-C", str(dest), "pull", "--ff-only"], check=True)
    else:
        _print(f"克隆: {repo} -> {dest}")
        subprocess.run(
            ["git", "clone", "--branch", ref, "--", repo, str(dest)],
            check=True,
        )


def cmd_install_external(args: argparse.Namespace) -> None:
    ensure_skills_home()
    registry = load_registry()
    if args.name not in registry:
        raise SystemExit(f"registry 中不存在: {args.name}")

    path = external_skill_path(args.name, registry[args.name])
    if not path.exists():
        raise SystemExit(f"请先 fetch: skiff fetch {args.name}")

    targets = resolve_targets(args.target)
    for target in targets:
        link = agent_skill_dir(target) / args.name
        create_link(link, path)
        _print(f"已安装外部 ({target}): {args.name} -> {path}")


def _project_root(args: argparse.Namespace) -> Path:
    if args.project:
        root = Path(args.project).resolve()
    else:
        root = find_repo_root() or Path.cwd()
    return root


def cmd_enable(args: argparse.Namespace) -> None:
    ensure_skills_home()
    validate_skill_name(args.name)
    root = _project_root(args)
    manifest_path = root / ".skills.yaml"

    # 判断来源
    registry = load_registry()
    if args.name in registry:
        source = "registry"
        extra = {"source": "registry", "ref": registry[args.name].get("ref", "main")}
        add_skill_to_manifest(manifest_path, args.name, source="registry", extra=extra)
    else:
        owned_skill_path(args.name)  # 验证存在
        add_skill_to_manifest(manifest_path, args.name, source="owned")

    targets = resolve_targets(args.target)
    _, data = load_manifest(manifest_path)
    manifest_targets = data.get("targets")
    if manifest_targets:
        targets = [t for t in targets if t in manifest_targets]

    _install_skill(args.name, targets, project_root=root)
    _print(f"已启用项目 skill: {args.name} @ {root}")


def cmd_disable(args: argparse.Namespace) -> None:
    root = _project_root(args)
    manifest_path = root / ".skills.yaml"
    if not remove_skill_from_manifest(manifest_path, args.name):
        _print(f"manifest 中不存在: {args.name}")
        return

    targets = resolve_targets(args.target)
    for target in targets:
        link = agent_skill_dir(target, project_root=root) / args.name
        if remove_link(link):
            _print(f"已禁用 ({target}): {link}")


def cmd_sync(args: argparse.Namespace) -> None:
    ensure_skills_home()
    root = _project_root(args)
    manifest_path = root / ".skills.yaml"
    if not manifest_path.is_file():
        raise SystemExit(f"未找到 {manifest_path}")

    _, data = load_manifest(manifest_path)
    targets = resolve_targets(args.target)
    manifest_targets = data.get("targets")
    if manifest_targets:
        targets = [t for t in targets if t in manifest_targets]

    for entry in iter_manifest_skills(data):
        name = entry["name"]
        skill_path, _ = resolve_manifest_skill(entry)
        for target in targets:
            link = agent_skill_dir(target, project_root=root) / name
            create_link(link, skill_path)
            _print(f"已同步: {link} -> {skill_path}")


def cmd_create(args: argparse.Namespace) -> None:
    ensure_skills_home()
    validate_skill_name(args.name)
    if not TEMPLATE_DIR.is_dir():
        raise SystemExit(f"模板目录不存在: {TEMPLATE_DIR}")

    dst = SKILLS_DIR / args.name
    copy_template(TEMPLATE_DIR, dst)

    skill_md = dst / "SKILL.md"
    content = skill_md.read_text(encoding="utf-8")
    content = re.sub(
        r"(^name:\s*)skill-name\s*$",
        rf"\g<1>{args.name}",
        content,
        count=1,
        flags=re.MULTILINE,
    )
    skill_md.write_text(content, encoding="utf-8")
    _print(f"已创建 skill: {dst}")
    _print(f"下一步: 编辑 {skill_md}，然后 skiff install {args.name}")


def cmd_doctor(args: argparse.Namespace) -> None:
    ensure_skills_home()
    targets = resolve_targets(args.target)
    issues = 0

    _print(f"skills 仓库: {SKILLS_HOME.resolve()}")
    if SKILLS_HOME.is_symlink():
        if not SKILLS_HOME.resolve().is_dir():
            _err(f"✗ ~/.skills 指向无效路径: {SKILLS_HOME.resolve()}")
            issues += 1
        else:
            _print("✓ ~/.skills 软链正常")
    elif SKILLS_HOME.is_dir() and (SKILLS_HOME / "skills").is_dir():
        _print("✓ ~/.skills 为本地仓库目录")
    else:
        _err("✗ ~/.skills 未正确配置")
        issues += 1

    for name in list_owned_skills():
        for target, link, expected in _installed_links(name, targets):
            status = check_link(link, expected)
            if status.ok:
                continue
            _err(f"✗ [{name}/{target}] {status.issue}: {link}")
            issues += 1
            if args.fix:
                try:
                    create_link(link, expected)
                    _print(f"  已修复: {link}")
                except Exception as exc:  # noqa: BLE001
                    _err(f"  修复失败: {exc}")

    registry = load_registry()
    for name in registry:
        ext = external_skill_path(name, registry[name])
        if not ext.exists():
            _err(f"✗ 外部 skill 未 fetch: {name}")
            issues += 1

    if issues == 0:
        _print("\n全部正常")
    else:
        _print(f"\n发现 {issues} 个问题")
        if not args.fix:
            _print("提示: 使用 skiff doctor --fix 尝试自动修复软链")
        sys.exit(1)


def build_parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(
        prog="skiff",
        description="Agent Skills 安装与管理 CLI",
    )
    parser.add_argument("--version", action="version", version=f"skiff {__version__}")

    sub = parser.add_subparsers(dest="command", required=True)

    p_setup = sub.add_parser("setup", help="关联 ~/.skills 到本仓库")
    p_setup.add_argument("path", help="skills 仓库路径")
    p_setup.set_defaults(func=cmd_setup)

    p_list = sub.add_parser("list", help="列出所有 skill")
    p_list.set_defaults(func=cmd_list)

    p_status = sub.add_parser("status", help="安装状态总览")
    p_status.add_argument("--target", choices=[*ALL_TARGETS, "all"], default="all")
    p_status.set_defaults(func=cmd_status)

    p_install = sub.add_parser("install", help="全局安装 skill（软链）")
    p_install.add_argument("name", help="skill 名称")
    p_install.add_argument("--target", choices=[*ALL_TARGETS, "all"], default="all")
    p_install.set_defaults(func=cmd_install)

    p_uninstall = sub.add_parser("uninstall", help="移除全局软链")
    p_uninstall.add_argument("name", help="skill 名称")
    p_uninstall.add_argument("--target", choices=[*ALL_TARGETS, "all"], default="all")
    p_uninstall.set_defaults(func=cmd_uninstall)

    p_add = sub.add_parser("add", help="添加外部 skill 到 registry")
    p_add.add_argument("name", help="registry 名称")
    p_add.add_argument("repo", help="Git 仓库 URL")
    p_add.add_argument("--ref", default="main", help="分支或 tag（默认 main）")
    p_add.add_argument("--path", default=".", help="仓库内子路径（默认 .）")
    p_add.set_defaults(func=cmd_add)

    p_fetch = sub.add_parser("fetch", help="拉取外部 Git skill")
    p_fetch.add_argument("name", help="registry 名称")
    p_fetch.set_defaults(func=cmd_fetch)

    p_inst_ext = sub.add_parser("install-external", help="安装外部 skill 到 Agent 目录")
    p_inst_ext.add_argument("name", help="registry 名称")
    p_inst_ext.add_argument("--target", choices=[*ALL_TARGETS, "all"], default="all")
    p_inst_ext.set_defaults(func=cmd_install_external)

    p_enable = sub.add_parser("enable", help="项目级启用 skill")
    p_enable.add_argument("name", help="skill 名称")
    p_enable.add_argument("--target", choices=[*ALL_TARGETS, "all"], default="all")
    p_enable.add_argument("--project", help="项目根目录（默认自动检测）")
    p_enable.set_defaults(func=cmd_enable)

    p_disable = sub.add_parser("disable", help="项目级禁用 skill")
    p_disable.add_argument("name", help="skill 名称")
    p_disable.add_argument("--target", choices=[*ALL_TARGETS, "all"], default="all")
    p_disable.add_argument("--project", help="项目根目录（默认自动检测）")
    p_disable.set_defaults(func=cmd_disable)

    p_sync = sub.add_parser("sync", help="按 .skills.yaml 重建项目软链")
    p_sync.add_argument("--target", choices=[*ALL_TARGETS, "all"], default="all")
    p_sync.add_argument("--project", help="项目根目录（默认自动检测）")
    p_sync.set_defaults(func=cmd_sync)

    p_create = sub.add_parser("create", help="从 _template 创建自研 skill")
    p_create.add_argument("name", help="skill 名称")
    p_create.set_defaults(func=cmd_create)

    p_doctor = sub.add_parser("doctor", help="软链健康检查")
    p_doctor.add_argument("--target", choices=[*ALL_TARGETS, "all"], default="all")
    p_doctor.add_argument("--fix", action="store_true", help="自动修复可修复的软链")
    p_doctor.set_defaults(func=cmd_doctor)

    return parser


def main(argv: list[str] | None = None) -> None:
    parser = build_parser()
    args = parser.parse_args(argv)
    args.func(args)


if __name__ == "__main__":
    main()