"""replace banjo/fiddle with instruments + tune_by_instrument tables

Revision ID: 84db90f5499e
Revises: 2bd4f3ff0ccc
Create Date: 2026-06-09
"""
from alembic import op
import sqlalchemy as sa

revision = "84db90f5499e"
down_revision = "2bd4f3ff0ccc"
branch_labels = None
depends_on = None


def upgrade() -> None:
    # 1. Drop old per-instrument tables (and their notes)
    op.drop_table("banjo")
    op.drop_table("fiddle")

    # Rename notes → tune_notes
    op.rename_table("notes", "tune_notes")

    # 2. Instruments lookup table
    op.create_table(
        "instruments",
        sa.Column("id",   sa.Integer(), primary_key=True, autoincrement=True, nullable=False),
        sa.Column("name", sa.String(),  nullable=False, unique=True),
    )
    # Seed banjo and fiddle
    op.execute("INSERT INTO instruments (name) VALUES ('banjo'), ('fiddle')")

    # 3. Generic tune_by_instrument table
    op.create_table(
        "tune_by_instrument",
        sa.Column("id",              sa.Integer(), primary_key=True, autoincrement=True, nullable=False),
        sa.Column("tune_id",         sa.Integer(),
                  sa.ForeignKey("tunes.id",       ondelete="CASCADE"),   nullable=False),
        sa.Column("instrument_id",   sa.Integer(),
                  sa.ForeignKey("instruments.id", ondelete="CASCADE"),   nullable=False),
        sa.Column("learned_from_id", sa.Integer(),
                  sa.ForeignKey("musicians.id",   ondelete="SET NULL"),  nullable=True),
        sa.Column("date_learned",    sa.Date(),    nullable=True),
        sa.Column("tuning",          sa.String(),  nullable=True),
        sa.Column("callable",        sa.Boolean(), nullable=True),
        sa.Column("review",          sa.Boolean(), nullable=True),
        sa.Column("to_learn",        sa.Boolean(), nullable=True),
        sa.Column("difficulty",      sa.String(),  nullable=True),
        sa.UniqueConstraint("tune_id", "instrument_id", name="uq_tune_instrument"),
    )

    # 4. Instrument-specific notes
    op.create_table(
        "tune_by_instrument_notes",
        sa.Column("id",                   sa.Integer(), primary_key=True, autoincrement=True, nullable=False),
        sa.Column("tune_by_instrument_id", sa.Integer(),
                  sa.ForeignKey("tune_by_instrument.id", ondelete="CASCADE"), nullable=False),
        sa.Column("note",                 sa.String(),  nullable=True),
    )


def downgrade() -> None:
    op.drop_table("tune_by_instrument_notes")
    op.drop_table("tune_by_instrument")
    op.drop_table("instruments")
    op.rename_table("tune_notes", "notes")
    op.create_table(
        "banjo",
        sa.Column("id",              sa.Integer(), primary_key=True, autoincrement=True, nullable=False),
        sa.Column("tune_id",         sa.Integer(), sa.ForeignKey("tunes.id",     ondelete="CASCADE"),  nullable=False, unique=True),
        sa.Column("learned_from_id", sa.Integer(), sa.ForeignKey("musicians.id", ondelete="SET NULL"), nullable=True),
        sa.Column("date_learned",    sa.Date(),    nullable=True),
        sa.Column("tuning",          sa.String(),  nullable=True),
        sa.Column("callable",        sa.Boolean(), nullable=True),
        sa.Column("review",          sa.Boolean(), nullable=True),
        sa.Column("to_learn",        sa.Boolean(), nullable=True),
        sa.Column("difficulty",      sa.String(),  nullable=True),
    )
    op.create_table(
        "fiddle",
        sa.Column("id",              sa.Integer(), primary_key=True, autoincrement=True, nullable=False),
        sa.Column("tune_id",         sa.Integer(), sa.ForeignKey("tunes.id",     ondelete="CASCADE"),  nullable=False, unique=True),
        sa.Column("learned_from_id", sa.Integer(), sa.ForeignKey("musicians.id", ondelete="SET NULL"), nullable=True),
        sa.Column("date_learned",    sa.Date(),    nullable=True),
        sa.Column("tuning",          sa.String(),  nullable=True),
        sa.Column("callable",        sa.Boolean(), nullable=True),
        sa.Column("review",          sa.Boolean(), nullable=True),
        sa.Column("to_learn",        sa.Boolean(), nullable=True),
        sa.Column("difficulty",      sa.String(),  nullable=True),
    )