import aiosqlite
from pathlib import Path

from app.config import settings

SCHEMA = """
CREATE TABLE IF NOT EXISTS drives (
    id              INTEGER PRIMARY KEY AUTOINCREMENT,
    truenas_disk_id TEXT    UNIQUE NOT NULL,
    devname         TEXT    NOT NULL,
    serial          TEXT,
    model           TEXT,
    size_bytes      INTEGER,
    temperature_c   INTEGER,
    smart_health    TEXT    DEFAULT 'UNKNOWN',
    last_seen_at    TEXT    NOT NULL,
    last_polled_at  TEXT    NOT NULL,
    notes           TEXT,
    location        TEXT
);

CREATE TABLE IF NOT EXISTS smart_tests (
    id              INTEGER PRIMARY KEY AUTOINCREMENT,
    drive_id        INTEGER NOT NULL REFERENCES drives(id) ON DELETE CASCADE,
    test_type       TEXT    NOT NULL CHECK(test_type IN ('short', 'long')),
    state           TEXT    NOT NULL DEFAULT 'idle',
    percent         INTEGER DEFAULT 0,
    truenas_job_id  INTEGER,
    started_at      TEXT,
    eta_at          TEXT,
    finished_at     TEXT,
    error_text      TEXT,
    UNIQUE(drive_id, test_type)
);

CREATE TABLE IF NOT EXISTS burnin_jobs (
    id          INTEGER PRIMARY KEY AUTOINCREMENT,
    drive_id    INTEGER NOT NULL REFERENCES drives(id),
    profile     TEXT    NOT NULL,
    state       TEXT    NOT NULL DEFAULT 'queued',
    percent     INTEGER DEFAULT 0,
    stage_name  TEXT,
    operator    TEXT    NOT NULL,
    created_at  TEXT    NOT NULL,
    started_at  TEXT,
    finished_at TEXT,
    error_text  TEXT
);

CREATE TABLE IF NOT EXISTS burnin_stages (
    id               INTEGER PRIMARY KEY AUTOINCREMENT,
    burnin_job_id    INTEGER NOT NULL REFERENCES burnin_jobs(id) ON DELETE CASCADE,
    stage_name       TEXT    NOT NULL,
    state            TEXT    NOT NULL DEFAULT 'pending',
    percent          INTEGER DEFAULT 0,
    started_at       TEXT,
    finished_at      TEXT,
    duration_seconds REAL,
    error_text       TEXT
);

CREATE TABLE IF NOT EXISTS audit_events (
    id            INTEGER PRIMARY KEY AUTOINCREMENT,
    event_type    TEXT    NOT NULL,
    drive_id      INTEGER REFERENCES drives(id),
    burnin_job_id INTEGER REFERENCES burnin_jobs(id),
    operator      TEXT,
    message       TEXT    NOT NULL,
    created_at    TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
);

CREATE INDEX IF NOT EXISTS idx_smart_drive_type   ON smart_tests(drive_id, test_type);
CREATE INDEX IF NOT EXISTS idx_burnin_jobs_drive  ON burnin_jobs(drive_id, state);
CREATE INDEX IF NOT EXISTS idx_burnin_stages_job  ON burnin_stages(burnin_job_id);
CREATE INDEX IF NOT EXISTS idx_audit_events_job   ON audit_events(burnin_job_id);
"""


# Migrations for existing databases that predate schema additions.
# Each entry is tried with try/except — SQLite raises OperationalError
# ("duplicate column name") if the column already exists, which is safe to ignore.
_MIGRATIONS = [
    "ALTER TABLE drives ADD COLUMN notes TEXT",
    "ALTER TABLE drives ADD COLUMN location TEXT",
    # Stage 7: SSH command output + SMART attribute storage
    "ALTER TABLE burnin_stages ADD COLUMN log_text TEXT",
    "ALTER TABLE burnin_stages ADD COLUMN bad_blocks INTEGER DEFAULT 0",
    "ALTER TABLE drives ADD COLUMN smart_attrs TEXT",
    "ALTER TABLE smart_tests ADD COLUMN raw_output TEXT",
    # Stage 8: track last reset time so dashboard burn-in col clears after reset
    "ALTER TABLE drives ADD COLUMN last_reset_at TEXT",
]


async def _run_migrations(db: aiosqlite.Connection) -> None:
    for sql in _MIGRATIONS:
        try:
            await db.execute(sql)
        except Exception:
            pass  # Column already exists — harmless

    # Remove the old CHECK(profile IN ('quick','full')) constraint if present.
    # SQLite can't ALTER a CHECK — requires a full table rebuild.
    cur = await db.execute(
        "SELECT sql FROM sqlite_master WHERE type='table' AND name='burnin_jobs'"
    )
    row = await cur.fetchone()
    if row and "CHECK" in (row[0] or ""):
        await db.executescript("""
            PRAGMA foreign_keys=OFF;
            CREATE TABLE burnin_jobs_new (
                id          INTEGER PRIMARY KEY AUTOINCREMENT,
                drive_id    INTEGER NOT NULL REFERENCES drives(id),
                profile     TEXT    NOT NULL,
                state       TEXT    NOT NULL DEFAULT 'queued',
                percent     INTEGER DEFAULT 0,
                stage_name  TEXT,
                operator    TEXT    NOT NULL,
                created_at  TEXT    NOT NULL,
                started_at  TEXT,
                finished_at TEXT,
                error_text  TEXT
            );
            INSERT INTO burnin_jobs_new SELECT * FROM burnin_jobs;
            DROP TABLE burnin_jobs;
            ALTER TABLE burnin_jobs_new RENAME TO burnin_jobs;
            CREATE INDEX IF NOT EXISTS idx_burnin_jobs_drive ON burnin_jobs(drive_id, state);
            PRAGMA foreign_keys=ON;
        """)


async def init_db() -> None:
    Path(settings.db_path).parent.mkdir(parents=True, exist_ok=True)
    async with aiosqlite.connect(settings.db_path) as db:
        await db.execute("PRAGMA journal_mode=WAL")
        await db.execute("PRAGMA foreign_keys=ON")
        await db.executescript(SCHEMA)
        await _run_migrations(db)
        await db.commit()


async def get_db():
    db = await aiosqlite.connect(settings.db_path)
    db.row_factory = aiosqlite.Row
    try:
        await db.execute("PRAGMA journal_mode=WAL")
        await db.execute("PRAGMA foreign_keys=ON")
        yield db
    finally:
        await db.close()