"""SQLAlchemy ORM 模型 — papers, authors, tags, summaries, user data, logs, locks。"""

from enum import StrEnum

from sqlalchemy import (
    Boolean,
    Column,
    Date,
    DateTime,
    ForeignKey,
    Integer,
    String,
    Text,
    UniqueConstraint,
    select,
)
from sqlalchemy.orm import joinedload, relationship

from app.database import Base


# ── 枚举 ────────────────────────────────────────────────────────────────


class SummaryState(StrEnum):
    """总结状态枚举 — 对应 summary_status.status 列。"""

    PENDING = "pending"
    PROCESSING = "processing"
    DONE = "done"
    FAILED = "failed"
    PERMANENT_FAILURE = "permanent_failure"


class JobStatus(StrEnum):
    """后台任务状态枚举 — 对应 jobs.status 列。"""

    QUEUED = "queued"
    RUNNING = "running"
    SUCCESS = "success"
    FAILED = "failed"
    STALE = "stale"
    CANCELLED = "cancelled"


class JobEventStatus(StrEnum):
    """任务阶段事件状态枚举 — 对应 job_events.status 列。"""

    STARTED = "started"
    SUCCESS = "success"
    FAILED = "failed"
    INFO = "info"


# ── papers ──────────────────────────────────────────────────────────────
class Paper(Base):
    __tablename__ = "papers"

    id = Column(Integer, primary_key=True, autoincrement=True)
    arxiv_id = Column(String, unique=True, nullable=False, index=True)
    title_en = Column(String, nullable=False)
    title_zh = Column(String)
    abstract = Column(Text)
    published_at = Column(Date)
    paper_date = Column(Date, nullable=False, index=True)
    crawled_at = Column(DateTime, nullable=False)
    upvotes = Column(Integer, default=0)
    hf_url = Column(String)
    arxiv_url = Column(String)
    pdf_url = Column(String)
    summary_path = Column(String)
    raw_output_path = Column(String)
    summary_quality = Column(String)

    authors = relationship(
        "PaperAuthor", back_populates="paper", cascade="all, delete-orphan"
    )
    tags = relationship(
        "PaperTag", back_populates="paper", cascade="all, delete-orphan"
    )
    summary = relationship(
        "PaperSummary",
        back_populates="paper",
        uselist=False,
        cascade="all, delete-orphan",
    )
    summary_status = relationship(
        "SummaryStatus",
        back_populates="paper",
        uselist=False,
        cascade="all, delete-orphan",
    )
    bookmark = relationship(
        "UserBookmark",
        back_populates="paper",
        uselist=False,
        cascade="all, delete-orphan",
    )
    reading_status = relationship(
        "UserReadingStatus",
        back_populates="paper",
        uselist=False,
        cascade="all, delete-orphan",
    )
    note = relationship(
        "UserNote", back_populates="paper", uselist=False, cascade="all, delete-orphan"
    )


# ── paper_authors ───────────────────────────────────────────────────────
class PaperAuthor(Base):
    __tablename__ = "paper_authors"
    __table_args__ = (UniqueConstraint("paper_id", "name"),)

    id = Column(Integer, primary_key=True, autoincrement=True)
    paper_id = Column(
        Integer, ForeignKey("papers.id", ondelete="CASCADE"), nullable=False, index=True
    )
    name = Column(String, nullable=False)
    position = Column(Integer, default=0)

    paper = relationship("Paper", back_populates="authors")


# ── paper_tags ──────────────────────────────────────────────────────────
class PaperTag(Base):
    __tablename__ = "paper_tags"
    __table_args__ = (UniqueConstraint("paper_id", "tag", "source"),)

    id = Column(Integer, primary_key=True, autoincrement=True)
    paper_id = Column(
        Integer, ForeignKey("papers.id", ondelete="CASCADE"), nullable=False, index=True
    )
    tag = Column(String, nullable=False)
    source = Column(String, default="hf")

    paper = relationship("Paper", back_populates="tags")


# ── paper_summaries ─────────────────────────────────────────────────────
class PaperSummary(Base):
    __tablename__ = "paper_summaries"

    paper_id = Column(
        Integer, ForeignKey("papers.id", ondelete="CASCADE"), primary_key=True
    )
    one_line = Column(Text)
    difficulty = Column(String)
    prerequisites_json = Column(Text)
    motivation_problem = Column(Text)
    motivation_goal = Column(Text)
    motivation_gap = Column(Text)
    method_overview = Column(Text)
    method_key_idea = Column(Text)
    method_steps_json = Column(Text)
    method_novelty = Column(Text)
    results_main_json = Column(Text)
    results_benchmarks_json = Column(Text)
    limitations_json = Column(Text)
    weaknesses_json = Column(Text)
    future_work_json = Column(Text)
    reproducibility = Column(String)
    figures_json = Column(Text)
    full_json = Column(Text, nullable=False)
    updated_at = Column(DateTime, nullable=False)

    paper = relationship("Paper", back_populates="summary")


# ── summary_status ──────────────────────────────────────────────────────
class SummaryStatus(Base):
    __tablename__ = "summary_status"
    __table_args__ = (UniqueConstraint("paper_id"),)

    id = Column(Integer, primary_key=True, autoincrement=True)
    paper_id = Column(
        Integer, ForeignKey("papers.id", ondelete="CASCADE"), nullable=False
    )
    status = Column(String, nullable=False, default="pending", index=True)
    quality = Column(String)
    error_type = Column(String)
    error = Column(Text)
    retry_count = Column(Integer, default=0)
    raw_output_saved = Column(Boolean, default=False)
    started_at = Column(DateTime)
    completed_at = Column(DateTime)

    paper = relationship("Paper", back_populates="summary_status")


# ── crawl_logs ──────────────────────────────────────────────────────────
class CrawlLog(Base):
    __tablename__ = "crawl_logs"

    id = Column(Integer, primary_key=True, autoincrement=True)
    task = Column(String, nullable=False)
    status = Column(String, nullable=False)
    date = Column(Date)
    papers_found = Column(Integer)
    papers_new = Column(Integer)
    error = Column(Text)
    details_json = Column(Text)  # 任务专用元数据 JSON（如 cleanup: {scanned, removed}）
    started_at = Column(DateTime, nullable=False)
    completed_at = Column(DateTime)


# ── task_locks ──────────────────────────────────────────────────────────
class TaskLock(Base):
    __tablename__ = "task_locks"

    id = Column(Integer, primary_key=True, autoincrement=True)
    task = Column(String, nullable=False)
    lock_key = Column(String, nullable=False)
    status = Column(String, nullable=False)
    owner = Column(String)
    acquired_at = Column(DateTime, nullable=False)
    heartbeat_at = Column(DateTime)
    expires_at = Column(DateTime)
    released_at = Column(DateTime)


# ── jobs / job_events ──────────────────────────────────────────────────
class Job(Base):
    __tablename__ = "jobs"

    id = Column(Integer, primary_key=True, autoincrement=True)
    type = Column(String, nullable=False, index=True)
    status = Column(String, nullable=False, default=JobStatus.QUEUED, index=True)
    owner = Column(String)
    payload_json = Column(Text)
    result_json = Column(Text)
    error = Column(Text)
    created_at = Column(DateTime, nullable=False)
    started_at = Column(DateTime)
    heartbeat_at = Column(DateTime)
    completed_at = Column(DateTime)

    events = relationship(
        "JobEvent", back_populates="job", cascade="all, delete-orphan"
    )


class JobEvent(Base):
    __tablename__ = "job_events"

    id = Column(Integer, primary_key=True, autoincrement=True)
    job_id = Column(
        Integer, ForeignKey("jobs.id", ondelete="CASCADE"), nullable=False, index=True
    )
    stage = Column(String, nullable=False)
    status = Column(String, nullable=False)
    message = Column(Text)
    payload_json = Column(Text)
    created_at = Column(DateTime, nullable=False)

    job = relationship("Job", back_populates="events")


# ── user data ──────────────────────────────────────────────────────────
class UserBookmark(Base):
    __tablename__ = "user_bookmarks"
    __table_args__ = (UniqueConstraint("paper_id"),)

    id = Column(Integer, primary_key=True, autoincrement=True)
    paper_id = Column(
        Integer, ForeignKey("papers.id", ondelete="CASCADE"), nullable=False
    )
    note = Column(Text)
    created_at = Column(DateTime, nullable=False)

    paper = relationship("Paper", back_populates="bookmark")


class UserReadingStatus(Base):
    __tablename__ = "user_reading_status"
    __table_args__ = (UniqueConstraint("paper_id"),)

    id = Column(Integer, primary_key=True, autoincrement=True)
    paper_id = Column(
        Integer, ForeignKey("papers.id", ondelete="CASCADE"), nullable=False
    )
    status = Column(String, nullable=False, default="unread", index=True)
    updated_at = Column(DateTime, nullable=False)

    paper = relationship("Paper", back_populates="reading_status")


class UserNote(Base):
    __tablename__ = "user_notes"
    __table_args__ = (UniqueConstraint("paper_id"),)

    id = Column(Integer, primary_key=True, autoincrement=True)
    paper_id = Column(
        Integer, ForeignKey("papers.id", ondelete="CASCADE"), nullable=False
    )
    content = Column(Text, nullable=False)
    created_at = Column(DateTime, nullable=False)
    updated_at = Column(DateTime, nullable=False)

    paper = relationship("Paper", back_populates="note")


# ── data_delete_jobs ───────────────────────────────────────────────────
class DataDeleteJob(Base):
    __tablename__ = "data_delete_jobs"

    id = Column(Integer, primary_key=True, autoincrement=True)
    date_start = Column(Date, nullable=False)
    date_end = Column(Date, nullable=False)
    include_notes = Column(Boolean, default=True)
    paper_count = Column(Integer, default=0)
    status = Column(String, nullable=False)
    error = Column(Text)
    started_at = Column(DateTime, nullable=False)
    completed_at = Column(DateTime)


# ── 常用 joinedload 选项集 ──────────────────────────────────────────────
# 避免在各路由/服务中重复写 .options(joinedload(Paper.authors), ...)

PAPER_DEFAULT_LOAD = (
    joinedload(Paper.authors),
    joinedload(Paper.tags),
    joinedload(Paper.summary_status),
)

PAPER_FULL_LOAD = (
    joinedload(Paper.authors),
    joinedload(Paper.tags),
    joinedload(Paper.summary_status),
    joinedload(Paper.bookmark),
    joinedload(Paper.reading_status),
)


def get_paper_by_arxiv_id(db, arxiv_id: str, *, load=PAPER_DEFAULT_LOAD):
    """按 arxiv_id 查询论文（带关联加载），未找到返回 None。"""
    stmt = select(Paper).where(Paper.arxiv_id == arxiv_id).options(*load)
    return db.execute(stmt).unique().scalar_one_or_none()


def get_paper_by_id(db, paper_id: int, *, load=PAPER_DEFAULT_LOAD):
    """按主键查询论文（带关联加载），未找到返回 None。"""
    stmt = select(Paper).where(Paper.id == paper_id).options(*load)
    return db.execute(stmt).unique().scalar_one_or_none()