"""AI 写作功能型 agent 的「调用前自检 + 缺失自动补建」工具。

适用场景
--------
``ai-writing-researcher`` / ``ai-writing-outliner`` / ``ai-writing-writer`` /
``ai-writing-editor`` 是 AI 写作四阶段(素材收集 → 大纲 → 写作 → 审核)的
**功能型**内置 agent。当 ``config.yaml`` 的 ``ai_writing.use_builtin_agents.*``
开关打开时,对应的图节点会从 ``.deer-flow/agents/<id>/`` 加载该 agent 的
SOUL.md(人设+结构化输出契约)与 config.yaml(可配 per-阶段模型)。

仓库根 ``.gitignore`` 把整个 ``.deer-flow/`` 目录排除,新机器 ``git clone``
之后这些目录**不会存在**。本模块在两个地方被调用:

1. **启动 lifespan**(``app/gateway/app.py``):服务起来就把缺失目录补齐,
   紧接着的 ``_sync_legacy_agents`` 会把它们 upsert 进 DB,新机器一启动
   ``/api/agents`` 列表里就有这四个 agent,admin 可直接在智能体管理页编辑
   SOUL / 模型。
2. **AI 写作路由入口**(``ai_writing.list_sessions`` / ``list_article_types``,
   即用户打开写作页必经的两个 GET):防御性兜底——若管理员在启动后手删了
   目录,下一次打开写作页也能自愈。

与 ``_roundtable_seed.py`` 完全同构:资源文件
(``_ai_writing_seed_assets/<id>/``)是发布默认值的唯一可信源,seeder 只在
目录缺失时字节级复制,**绝不覆盖**已存在目录(尊重运维/admin 现场手改)。
线上调优 SOUL 后请把改动写回对应资源 .md,否则新机器补建出来的还是旧版。

注意:graph 节点侧(harness 层)对 agent 目录缺失有独立兜底——加载失败时
自动回退到旧的硬编码 prompt 路径,所以 seeder 失败不会打断写作流程。
"""

from __future__ import annotations

import logging
from collections.abc import Iterable
from pathlib import Path

from deerflow.config.paths import get_paths

logger = logging.getLogger(__name__)


RESEARCHER_AGENT_ID = "ai-writing-researcher"
OUTLINER_AGENT_ID = "ai-writing-outliner"
WRITER_AGENT_ID = "ai-writing-writer"
EDITOR_AGENT_ID = "ai-writing-editor"

# 验证版 SOUL.md + config.yaml 的源码资源目录(随 git 发布)。每个子目录名即 agent id。
_ASSETS_DIR = Path(__file__).parent / "_ai_writing_seed_assets"

# 四个功能型内置 agent,任何部署都应存在;顺序无关紧要(逐个独立补建)。
_FUNCTIONAL_AGENT_IDS: tuple[str, ...] = (
    RESEARCHER_AGENT_ID,
    OUTLINER_AGENT_ID,
    WRITER_AGENT_ID,
    EDITOR_AGENT_ID,
)

# seeder 会复制资源目录里的这些文件(存在即复制,缺失则跳过)。
_SEED_FILES: tuple[str, ...] = ("config.yaml", "SOUL.md")

# 内置「知识库检索」技能:素材收集专家通用检索的默认技能。skills/ 目录被
# .gitignore 排除,所以与 agent 目录一样需要 seeder 在缺失时从资源补建。
KNOWLEDGE_SEARCH_SKILL_NAME = "knowledge-base-search"
_SKILL_ASSETS_DIR = _ASSETS_DIR / "skills"


def _ensure_one(agent_id: str) -> bool:
    """Copy the verified SOUL.md + config.yaml for one functional agent into
    ``.deer-flow/agents/<id>/`` if that directory is missing.

    Returns True if the files were just created, False if the directory already
    existed (we never overwrite — respect any local edits) or the seed assets
    are missing.
    """
    agent_dir = get_paths().agent_dir(agent_id)
    if agent_dir.exists():
        return False

    src_dir = _ASSETS_DIR / agent_id
    if not src_dir.is_dir():
        # Assets should always ship with the code; if they don't, surface a loud
        # log instead of silently creating an empty agent dir.
        logger.error(
            "Missing seed assets for ai-writing agent '%s' (expected at %s)",
            agent_id,
            src_dir,
        )
        return False

    agent_dir.mkdir(parents=True, exist_ok=True)
    for fname in _SEED_FILES:
        src = src_dir / fname
        if src.exists():
            # 字节级复制,保留验证版文件原样(换行/编码),与资源文件 hash 对齐。
            (agent_dir / fname).write_bytes(src.read_bytes())
    return True


def _skills_public_dir() -> Path:
    """skills/public 物理目录(config.yaml skills.path 解析);独立成函数便于测试替身。"""
    from deerflow.skills.storage import get_or_new_skill_storage

    return Path(get_or_new_skill_storage().get_skills_root_path()) / "public"


def _ensure_default_search_skill() -> bool:
    """Seed the built-in knowledge-base-search skill into ``skills/public/``
    when missing. Never overwrites an existing skill directory.

    Returns True if the skill was just created.
    """
    src = _SKILL_ASSETS_DIR / KNOWLEDGE_SEARCH_SKILL_NAME / "SKILL.md"
    if not src.exists():
        logger.error("Missing seed asset for skill '%s' (expected at %s)", KNOWLEDGE_SEARCH_SKILL_NAME, src)
        return False

    skill_dir = _skills_public_dir() / KNOWLEDGE_SEARCH_SKILL_NAME
    if skill_dir.exists():
        return False
    skill_dir.mkdir(parents=True, exist_ok=True)
    (skill_dir / "SKILL.md").write_bytes(src.read_bytes())
    return True


def _ensure_researcher_default_skills() -> bool:
    """给**已存在**的 researcher agent config.yaml 补默认技能配置(就地升级)。

    seeder 对已存在目录绝不整体覆盖,但旧版种子没有 ``skills`` 字段——通用
    检索改为技能驱动后,老部署的智能体管理页会显示"未配置技能"(运行时虽有
    knowledge-base-search 兜底,但用户看不见、也没法在它基础上增删)。只在
    ``skills`` 键**完全缺失**时补默认值;用户显式改过(包括清空成 ``[]``)
    的配置不动。Returns True if the file was patched.
    """
    import yaml

    config_file = get_paths().agent_dir(RESEARCHER_AGENT_ID) / "config.yaml"
    if not config_file.exists():
        return False
    try:
        data = yaml.safe_load(config_file.read_text(encoding="utf-8")) or {}
    except yaml.YAMLError:
        logger.warning("researcher config.yaml unparsable, skip default-skills patch")
        return False
    if not isinstance(data, dict) or "skills" in data:
        return False
    data["skills"] = [KNOWLEDGE_SEARCH_SKILL_NAME]
    config_file.write_text(
        yaml.safe_dump(data, allow_unicode=True, sort_keys=False),
        encoding="utf-8",
    )
    return True


def ensure_ai_writing_functional_agents() -> list[str]:
    """Seed the four ai-writing functional agents if their on-disk directories
    are missing. Idempotent — fast no-op when all exist.

    Also seeds the built-in knowledge-base-search skill (the researcher's
    default retrieval skill) and patches a pre-existing researcher config.yaml
    that predates the ``skills`` field.

    Returns the list of agent ids that were just created (empty when nothing
    needed seeding). Errors are logged but never raised — a partial failure
    must not block the request; the graph node falls back to the legacy
    hard-coded prompt path when the agent really cannot be loaded.
    """
    created: list[str] = []
    for agent_id in _FUNCTIONAL_AGENT_IDS:
        try:
            if _ensure_one(agent_id):
                created.append(agent_id)
        except Exception:
            logger.exception("Failed to seed ai-writing functional agent '%s'", agent_id)
    if created:
        logger.info("Seeded missing ai-writing functional agents: %s", ", ".join(created))
    try:
        if _ensure_default_search_skill():
            logger.info("Seeded built-in skill '%s'", KNOWLEDGE_SEARCH_SKILL_NAME)
    except Exception:
        logger.exception("Failed to seed built-in skill '%s'", KNOWLEDGE_SEARCH_SKILL_NAME)
    try:
        if _ensure_researcher_default_skills():
            logger.info("Patched researcher config.yaml with default skills")
    except Exception:
        logger.exception("Failed to patch researcher default skills")
    return created


def required_agent_ids() -> Iterable[str]:
    """Stable ids of agents this seeder owns — exposed for tests/diagnostics."""
    return tuple(_FUNCTIONAL_AGENT_IDS)