"""修复 injuries 表约束命名与 ORM 声明不一致

Revision ID: 0007_injuries_constraint_naming_align
Revises: 0006_schema_model_drift_cleanup
Create Date: 2026-09-16

背景(见代码审查报告 P2-5):
  0003 迁移使用 sa.UniqueConstraint 创建唯一约束,
  而 ORM models.py 中声明为 Index(..., unique=True)。
  虽然 PostgreSQL 中两者效果相同(都保证唯一性),
  但 pg_catalog 中表示不同,会导致:
    - alembic autogenerate 持续报告漂移
    - 约束命名约定不一致(uc_ 前缀 vs ix_ 前缀)

  本迁移将 UniqueConstraint 替换为唯一索引,与 ORM 声明对齐。
"""

from typing import Sequence, Union

from alembic import op
import sqlalchemy as sa

# revision identifiers, used by Alembic.
revision: str = '0007_injuries_constraint_naming_align'
down_revision: Union[str, None] = '0006_schema_model_drift_cleanup'
branch_labels: Union[str, Sequence[str], None] = None
depends_on: Union[str, Sequence[str], None] = None


def upgrade() -> None:
    bind = op.get_bind()
    inspector = sa.inspect(bind)

    # 检查当前约束类型
    constraints = {
        c["name"]: c
        for c in inspector.get_unique_constraints("injuries")
    }
    indexes = {
        i["name"]: i
        for i in inspector.get_indexes("injuries")
    }

    # 如果存在 UniqueConstraint 形式的 ix_injuries_player_fixture,替换为唯一索引
    if "ix_injuries_player_fixture" in constraints:
        # 删除唯一约束
        op.drop_constraint("ix_injuries_player_fixture", "injuries", type_="unique")

    # 如果不存在同名唯一索引,创建它(与 ORM 声明一致)
    if "ix_injuries_player_fixture" not in indexes:
        op.create_index(
            "ix_injuries_player_fixture",
            "injuries",
            ["player_id", "fixture_id", "injury_type"],
            unique=True,
        )


def downgrade() -> None:
    bind = op.get_bind()
    inspector = sa.inspect(bind)

    indexes = {
        i["name"]: i
        for i in inspector.get_indexes("injuries")
    }
    constraints = {
        c["name"]: c
        for c in inspector.get_unique_constraints("injuries")
    }

    # 恢复为 UniqueConstraint 形式
    if "ix_injuries_player_fixture" in indexes:
        op.drop_index("ix_injuries_player_fixture", table_name="injuries")

    if "ix_injuries_player_fixture" not in constraints:
        op.create_unique_constraint(
            "ix_injuries_player_fixture",
            "injuries",
            ["player_id", "fixture_id", "injury_type"],
        )