from contextlib import contextmanager
import time
from typing import Iterator

from psycopg.rows import dict_row
import psycopg

from .config import DATABASE_URL


SCHEMA_SQL = """
CREATE TABLE IF NOT EXISTS members (
    id SERIAL PRIMARY KEY,
    name TEXT NOT NULL,
    employee_id TEXT,
    company TEXT,
    rank TEXT,
    role TEXT,
    department TEXT,
    grp TEXT,
    division TEXT,
    team TEXT,
    cell TEXT,
    work_status TEXT,
    work_time TEXT,
    phone TEXT,
    email TEXT,
    seat_label TEXT,
    photo_url TEXT,
    sort_order INTEGER NOT NULL DEFAULT 0,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS seat_maps (
    id SERIAL PRIMARY KEY,
    name TEXT NOT NULL,
    image_url TEXT NOT NULL,
    source_type TEXT NOT NULL DEFAULT 'image',
    source_url TEXT,
    preview_svg TEXT,
    view_box_min_x DOUBLE PRECISION,
    view_box_min_y DOUBLE PRECISION,
    view_box_width DOUBLE PRECISION,
    view_box_height DOUBLE PRECISION,
    image_width INTEGER,
    image_height INTEGER,
    grid_rows INTEGER NOT NULL,
    grid_cols INTEGER NOT NULL,
    cell_gap INTEGER NOT NULL DEFAULT 0,
    is_active BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS seat_positions (
    member_id INTEGER PRIMARY KEY REFERENCES members(id) ON DELETE CASCADE,
    seat_map_id INTEGER REFERENCES seat_maps(id) ON DELETE CASCADE,
    seat_slot_id INTEGER,
    row_index INTEGER NOT NULL DEFAULT 0,
    col_index INTEGER NOT NULL DEFAULT 0,
    seat_label TEXT,
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS seat_slots (
    id SERIAL PRIMARY KEY,
    seat_map_id INTEGER NOT NULL REFERENCES seat_maps(id) ON DELETE CASCADE,
    slot_key TEXT NOT NULL,
    label TEXT NOT NULL,
    x DOUBLE PRECISION NOT NULL,
    y DOUBLE PRECISION NOT NULL,
    rotation DOUBLE PRECISION NOT NULL DEFAULT 0,
    layer_name TEXT NOT NULL DEFAULT 'chair',
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE (seat_map_id, slot_key)
);
"""

MIGRATION_SQL = """
ALTER TABLE members ADD COLUMN IF NOT EXISTS employee_id TEXT;
ALTER TABLE members ADD COLUMN IF NOT EXISTS sort_order INTEGER NOT NULL DEFAULT 0;
ALTER TABLE seat_positions ADD COLUMN IF NOT EXISTS seat_map_id INTEGER REFERENCES seat_maps(id) ON DELETE CASCADE;
ALTER TABLE seat_positions ADD COLUMN IF NOT EXISTS seat_slot_id INTEGER;
ALTER TABLE seat_positions ADD COLUMN IF NOT EXISTS row_index INTEGER NOT NULL DEFAULT 0;
ALTER TABLE seat_positions ADD COLUMN IF NOT EXISTS col_index INTEGER NOT NULL DEFAULT 0;
ALTER TABLE seat_positions ADD COLUMN IF NOT EXISTS seat_label TEXT;
ALTER TABLE seat_positions ADD COLUMN IF NOT EXISTS updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW();
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS source_type TEXT NOT NULL DEFAULT 'image';
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS source_url TEXT;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS preview_svg TEXT;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS view_box_min_x DOUBLE PRECISION;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS view_box_min_y DOUBLE PRECISION;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS view_box_width DOUBLE PRECISION;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS view_box_height DOUBLE PRECISION;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS image_width INTEGER;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS image_height INTEGER;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS cell_gap INTEGER NOT NULL DEFAULT 0;
ALTER TABLE seat_maps ADD COLUMN IF NOT EXISTS is_active BOOLEAN NOT NULL DEFAULT FALSE;
ALTER TABLE seat_maps ALTER COLUMN image_url DROP NOT NULL;

CREATE TABLE IF NOT EXISTS seat_slots (
    id SERIAL PRIMARY KEY,
    seat_map_id INTEGER NOT NULL REFERENCES seat_maps(id) ON DELETE CASCADE,
    slot_key TEXT NOT NULL,
    label TEXT NOT NULL,
    x DOUBLE PRECISION NOT NULL,
    y DOUBLE PRECISION NOT NULL,
    rotation DOUBLE PRECISION NOT NULL DEFAULT 0,
    layer_name TEXT NOT NULL DEFAULT 'chair',
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE (seat_map_id, slot_key)
);

DO $$
BEGIN
    IF EXISTS (
        SELECT 1
        FROM information_schema.columns
        WHERE table_name = 'seat_positions' AND column_name = 'x'
    ) THEN
        EXECUTE 'UPDATE seat_positions SET row_index = COALESCE(y, row_index, 0), col_index = COALESCE(x, col_index, 0) WHERE seat_map_id IS NULL';
    END IF;
END $$;

DO $$
BEGIN
    IF EXISTS (
        SELECT 1
        FROM information_schema.columns
        WHERE table_name = 'seat_positions' AND column_name = 'floor_label'
    ) THEN
        EXECUTE 'UPDATE seat_positions SET seat_label = COALESCE(seat_label, floor_label) WHERE seat_label IS NULL';
    END IF;
END $$;

CREATE UNIQUE INDEX IF NOT EXISTS seat_positions_map_cell_idx
ON seat_positions (seat_map_id, row_index, col_index)
WHERE seat_map_id IS NOT NULL;

CREATE UNIQUE INDEX IF NOT EXISTS seat_positions_slot_idx
ON seat_positions (seat_slot_id)
WHERE seat_slot_id IS NOT NULL;

DO $$
BEGIN
    IF NOT EXISTS (
        SELECT 1
        FROM information_schema.table_constraints
        WHERE constraint_name = 'seat_positions_seat_slot_id_fkey'
          AND table_name = 'seat_positions'
    ) THEN
        ALTER TABLE seat_positions
        ADD CONSTRAINT seat_positions_seat_slot_id_fkey
        FOREIGN KEY (seat_slot_id) REFERENCES seat_slots(id) ON DELETE CASCADE;
    END IF;
END $$;
"""


@contextmanager
def get_conn() -> Iterator[psycopg.Connection]:
    with psycopg.connect(DATABASE_URL, row_factory=dict_row) as conn:
        yield conn


def init_db(max_retries: int = 20, retry_delay: float = 2.0) -> None:
    last_error: Exception | None = None
    for _ in range(max_retries):
        try:
            with get_conn() as conn:
                with conn.cursor() as cur:
                    cur.execute(SCHEMA_SQL)
                    cur.execute(MIGRATION_SQL)
                conn.commit()
            return
        except psycopg.OperationalError as exc:
            last_error = exc
            time.sleep(retry_delay)
    if last_error is not None:
        raise last_error