"""Main toxicity analysis orchestrator.

Runs as a one-shot batch process: fetches unscored statuses,
classifies them in batches with GPT-4o-mini, and stores scores in PostgreSQL.

Usage:
    python -m app.analyzer
    ANALYZER_LIMIT=100 python -m app.analyzer   # test on 100 statuses
"""

from __future__ import annotations

import asyncio
import logging
import os
import sys
import time

from .classifier import ToxicityClassifier
from .config import AnalyzerConfig
from .db import AnalyzerDB

logger = logging.getLogger("analyzer")


def make_batches(items: list, batch_size: int) -> list[list]:
    """Split a flat list into sublists of at most batch_size."""
    return [items[i : i + batch_size] for i in range(0, len(items), batch_size)]


async def classify_statuses(
    classifier: ToxicityClassifier,
    db: AnalyzerDB,
    statuses: list[dict],
    config: AnalyzerConfig,
) -> tuple[int, int, float]:
    """Classify statuses in batches, with concurrency control.

    Returns (scored_count, error_count, cost_usd).
    """
    semaphore = asyncio.Semaphore(config.concurrency)
    scored = 0
    errors = 0
    total_input_tokens = 0
    total_output_tokens = 0

    batches = make_batches(statuses, config.batch_size)
    logger.info("  Split %d statuses into %d batches of ≤%d",
                len(statuses), len(batches), config.batch_size)

    async def process_batch(batch: list[dict]) -> None:
        nonlocal scored, errors, total_input_tokens, total_output_tokens
        async with semaphore:
            texts = [s["content"] for s in batch]
            try:
                results = await classifier.classify_batch(texts)

                for status, scores in zip(batch, results):
                    try:
                        score_dict = scores.to_dict()
                        flagged = scores.is_flagged(config.flag_threshold)

                        await db.store_status_score(
                            status_id=status["id"],
                            scores=score_dict,
                            flagged=flagged,
                            model=config.model,
                        )

                        total_input_tokens += scores.input_tokens
                        total_output_tokens += scores.output_tokens
                        scored += 1

                    except Exception:
                        errors += 1
                        logger.exception(
                            "Failed to store score for status %d", status["id"]
                        )

                if scored % 100 < config.batch_size:
                    logger.info("  Statuses scored: %d / %d", scored, len(statuses))

            except Exception:
                # Whole batch failed (API error after retries) — count all as errors
                errors += len(batch)
                logger.exception(
                    "Failed to classify batch of %d statuses", len(batch)
                )

    tasks = [process_batch(b) for b in batches]
    await asyncio.gather(*tasks)

    cost = (
        total_input_tokens * config.input_cost_per_m / 1_000_000
        + total_output_tokens * config.output_cost_per_m / 1_000_000
    )
    return scored, errors, cost


async def run() -> None:
    config = AnalyzerConfig.from_env()

    logging.basicConfig(
        level=getattr(logging, config.log_level.upper(), logging.INFO),
        format="%(asctime)s [%(levelname)s] %(name)s: %(message)s",
        handlers=[logging.StreamHandler(sys.stdout)],
    )
    # Also log to file
    log_dir = "/app/logs"
    if os.path.isdir(log_dir):
        fh = logging.FileHandler(os.path.join(log_dir, "analyzer.log"))
        fh.setFormatter(
            logging.Formatter("%(asctime)s [%(levelname)s] %(name)s: %(message)s")
        )
        logging.getLogger().addHandler(fh)

    logger.info("=" * 60)
    logger.info("Toxicity Analyzer starting (model: %s, concurrency: %d, batch_size: %d)",
                config.model, config.concurrency, config.batch_size)

    db = AnalyzerDB(config.database_url)
    classifier = ToxicityClassifier(
        api_key=config.openai_api_key,
        model=config.model,
    )

    try:
        await db.connect()
        await db.apply_migration()

        # Start analysis run
        run_id = await db.start_analysis_run(model=config.model)
        start_time = time.time()

        # Fetch unscored items
        limit = config.limit if config.limit > 0 else 0
        statuses = await db.get_unscored_statuses(limit=limit)

        logger.info("Found %d unscored statuses", len(statuses))

        if not statuses:
            logger.info("Nothing to score — exiting.")
            await db.finish_analysis_run(
                run_id, status="completed",
                statuses_scored=0, errors=0, cost_usd=0.0,
            )
            return

        total_cost = 0.0
        total_errors = 0

        # Classify statuses
        logger.info("Classifying %d statuses in batches of %d...",
                    len(statuses), config.batch_size)
        s_scored, s_errors, s_cost = await classify_statuses(
            classifier, db, statuses, config,
        )
        logger.info("  Statuses done: %d scored, %d errors, $%.4f",
                     s_scored, s_errors, s_cost)
        total_cost += s_cost
        total_errors += s_errors

        # Finalize run
        duration = time.time() - start_time
        status = "completed" if total_errors == 0 else "partial"
        await db.finish_analysis_run(
            run_id,
            status=status,
            statuses_scored=s_scored,
            errors=total_errors,
            cost_usd=total_cost,
        )

        logger.info("=" * 60)
        logger.info("Analysis complete — status: %s", status)
        logger.info("  Statuses scored: %d, Errors: %d",
                     s_scored, total_errors)
        logger.info("  Estimated cost: $%.4f", total_cost)
        logger.info("  Duration: %.1f seconds", duration)

    except Exception:
        logger.exception("Analyzer crashed")
        raise
    finally:
        await classifier.close()
        await db.close()


def main() -> None:
    asyncio.run(run())


if __name__ == "__main__":
    main()