"""Ingest pipeline: auto-detect format, parse, write to SQLite."""
from __future__ import annotations

import json
import logging
import re
import sqlite3
from pathlib import Path
from typing import Iterator

from app.ingest import caddy, docker_log, journald, plaintext, plex, qbittorrent
from app.ingest.base import _compile, load_patterns, now_iso
from app.services.models import LogPattern, RetrievedEntry
from app.services.search import build_fts_index

logger = logging.getLogger(__name__)

_SCHEMA = """
CREATE TABLE IF NOT EXISTS log_entries (
    id              TEXT PRIMARY KEY,
    source_id       TEXT NOT NULL,
    sequence        INTEGER NOT NULL,
    timestamp_raw   TEXT,
    timestamp_iso   TEXT,
    ingest_time     TEXT NOT NULL,
    severity        TEXT,
    repeat_count    INTEGER DEFAULT 1,
    out_of_order    INTEGER DEFAULT 0,
    matched_patterns TEXT DEFAULT '[]',
    text            TEXT NOT NULL
);
CREATE INDEX IF NOT EXISTS idx_source    ON log_entries(source_id);
CREATE INDEX IF NOT EXISTS idx_timestamp ON log_entries(timestamp_iso);
CREATE INDEX IF NOT EXISTS idx_severity  ON log_entries(severity);
CREATE INDEX IF NOT EXISTS idx_patterns  ON log_entries(matched_patterns);

CREATE TABLE IF NOT EXISTS incidents (
    id          TEXT PRIMARY KEY,
    label       TEXT NOT NULL,
    started_at  TEXT,
    ended_at    TEXT,
    notes       TEXT NOT NULL DEFAULT '',
    created_at  TEXT NOT NULL,
    severity    TEXT NOT NULL DEFAULT 'medium'
);
CREATE INDEX IF NOT EXISTS idx_incidents_time ON incidents(started_at, ended_at);
"""


def ensure_schema(db_path: Path) -> None:
    """Create all tables if they don't exist. Safe to call on every startup."""
    conn = sqlite3.connect(str(db_path))
    conn.execute("PRAGMA journal_mode=WAL")
    conn.executescript(_SCHEMA)
    conn.commit()
    conn.close()


def _detect_format(first_line: str) -> str:
    try:
        obj = json.loads(first_line)
        if "__REALTIME_TIMESTAMP" in obj:
            return "journald"
        if "SOURCE" in obj and str(obj.get("SOURCE", "")).startswith("docker:"):
            return "docker"
        if "ts" in obj and ("msg" in obj or "message" in obj or "request" in obj):
            return "caddy"
    except (json.JSONDecodeError, AttributeError):
        pass
    if plex.is_plex_log(first_line):
        return "plex"
    if qbittorrent.is_qbit_log(first_line):
        return "qbittorrent"
    return "plaintext"


def _parse_file(
    path: Path,
    compiled: list[tuple[LogPattern, object]],
    ingest_time: str,
) -> Iterator[RetrievedEntry]:
    source_id = path.stem

    with path.open("r", errors="replace") as f:
        lines = iter(f)
        try:
            first = next(lines)
        except StopIteration:
            return

        fmt = _detect_format(first.strip())
        logger.info("Detected format %r for %s", fmt, path.name)

        def all_lines():
            yield first
            yield from lines

        if fmt == "journald":
            yield from journald.parse(all_lines(), source_id, compiled, ingest_time)
        elif fmt == "docker":
            yield from docker_log.parse(all_lines(), source_id, compiled, ingest_time)
        elif fmt == "caddy":
            yield from caddy.parse(all_lines(), source_id, compiled, ingest_time)
        elif fmt == "plex":
            yield from plex.parse(all_lines(), source_id, compiled, ingest_time)
        elif fmt == "qbittorrent":
            yield from qbittorrent.parse(all_lines(), source_id, compiled, ingest_time)
        else:
            yield from plaintext.parse(all_lines(), source_id, compiled, ingest_time)


def _write_batch(conn: sqlite3.Connection, batch: list[RetrievedEntry]) -> None:
    conn.executemany(
        """
        INSERT OR IGNORE INTO log_entries
          (id, source_id, sequence, timestamp_raw, timestamp_iso,
           ingest_time, severity, repeat_count, out_of_order,
           matched_patterns, text)
        VALUES (?,?,?,?,?,?,?,?,?,?,?)
        """,
        [
            (
                e.entry_id, e.source_id, e.sequence,
                e.timestamp_raw, e.timestamp_iso, e.ingest_time,
                e.severity, e.repeat_count, int(e.out_of_order),
                json.dumps(list(e.matched_patterns)), e.text,
            )
            for e in batch
        ],
    )


def _ingest_files(
    files: list[Path],
    db_path: Path,
    pattern_file: Path | None = None,
    batch_size: int = 1000,
) -> dict[str, int]:
    pattern_file = pattern_file or Path("patterns/default.yaml")
    patterns = load_patterns(pattern_file)
    compiled = _compile(patterns)
    ingest_time = now_iso()

    conn = sqlite3.connect(str(db_path))
    conn.execute("PRAGMA journal_mode=WAL")
    conn.executescript(_SCHEMA)
    conn.commit()

    stats: dict[str, int] = {}

    for log_file in files:
        count = 0
        batch: list[RetrievedEntry] = []
        for entry in _parse_file(log_file, compiled, ingest_time):
            batch.append(entry)
            if len(batch) >= batch_size:
                _write_batch(conn, batch)
                conn.commit()
                count += len(batch)
                batch.clear()
        if batch:
            _write_batch(conn, batch)
            conn.commit()
            count += len(batch)
        stats[log_file.name] = count
        logger.info("Ingested %d entries from %s", count, log_file.name)

    conn.close()

    logger.info("Building FTS index...")
    build_fts_index(db_path)
    logger.info("FTS index ready")

    return stats


def ingest(
    corpus_dir: Path,
    db_path: Path,
    pattern_file: Path | None = None,
    batch_size: int = 1000,
) -> dict[str, int]:
    """Ingest all .jsonl and .log files from a corpus directory."""
    files = sorted(corpus_dir.glob("*.jsonl")) + sorted(corpus_dir.glob("*.log"))
    return _ingest_files(files, db_path, pattern_file, batch_size)


def ingest_file(
    log_file: Path,
    db_path: Path,
    pattern_file: Path | None = None,
) -> dict[str, int]:
    """Ingest a single log file (any supported format)."""
    return _ingest_files([log_file], db_path, pattern_file)