from __future__ import annotations

import logging
from datetime import datetime
from typing import Any
from zoneinfo import ZoneInfo

import aiosqlite
import httpx

from server.db import utc_now_iso
from server.messages import pick
from server.settings import settings
from server.stats import compute_stats

logger = logging.getLogger(__name__)

MOTIVATION_SYSTEM = (
    "Du schreibst Tages-Motivationssprüche für 'ADHD live, laugh, toaster bath motivational'. "
    "Stil: dark humor, Sarkasmus, passiv-aggressiv, kreativ-motivierend — nie gemein, nie medizinisch. "
    "Genau ein Satz auf Deutsch, max 25 Wörter. Keine Anführungszeichen um den Spruch."
)

ORACLE_SYSTEM = (
    "Du bist das wöchentliche KI-Orakel einer ADHS-Medikamenten-App. "
    "Passiv-aggressiv, trocken, max 4 Sätze auf Deutsch. Keine medizinischen Ratschläge."
)


async def _get_cache(db: aiosqlite.Connection, key: str) -> str | None:
    cur = await db.execute("SELECT content FROM ai_cache WHERE key = ?", (key,))
    row = await cur.fetchone()
    await cur.close()
    return row[0] if row else None


async def _set_cache(db: aiosqlite.Connection, key: str, content: str) -> None:
    await db.execute(
        "INSERT INTO ai_cache (key, content, created_at) VALUES (?, ?, ?) ON CONFLICT(key) DO UPDATE SET content=excluded.content, created_at=excluded.created_at",
        (key, content, utc_now_iso()),
    )
    await db.commit()


async def _call_openrouter(prompt: str, *, system: str) -> str | None:
    if not settings.openrouter_api_key:
        return None
    try:
        async with httpx.AsyncClient(timeout=30.0) as client:
            resp = await client.post(
                "https://openrouter.ai/api/v1/chat/completions",
                headers={
                    "Authorization": f"Bearer {settings.openrouter_api_key}",
                    "HTTP-Referer": "https://medis.schwenk.online",
                    "X-Title": "TakeYourMeds",
                },
                json={
                    "model": settings.openrouter_model,
                    "messages": [
                        {"role": "system", "content": system},
                        {"role": "user", "content": prompt},
                    ],
                    "max_tokens": 120,
                },
            )
            resp.raise_for_status()
            data = resp.json()
            return data["choices"][0]["message"]["content"].strip()
    except Exception:
        logger.exception("OpenRouter request failed")
        return None


def _motivation_key(day: str) -> str:
    return f"motivation:{day}"


async def _cached_motivation(db: aiosqlite.Connection, day: str) -> str | None:
    cached = await _get_cache(db, _motivation_key(day))
    if cached:
        return cached
    return await _get_cache(db, f"roast:{day}")


async def generate_daily_motivation(
    db: aiosqlite.Connection,
    tz: ZoneInfo,
    day: str | None = None,
) -> dict[str, Any]:
    day = day or datetime.now(tz).strftime("%Y-%m-%d")
    key = _motivation_key(day)
    cached = await _cached_motivation(db, day)
    if cached:
        return {"text": cached, "source": "cache", "day": day}

    stats = await compute_stats(db)
    prompt = (
        "Schreibe den Motivationsspruch für heute. "
        f"Streak: {stats['streak']} Tage. "
        f"Compliance über {stats['compliance_window_days']} aktive Tage: {stats['compliance_percent']}%. "
        "Beispiel-Stil: Dein Gehirn ist nicht kaputt. Es läuft nur auf einem anderen Betriebssystem — ohne Support."
    )
    text = await _call_openrouter(prompt, system=MOTIVATION_SYSTEM)
    if not text:
        text = pick("motivation_fallback")
        source = "fallback"
    else:
        source = "ai"
    await _set_cache(db, key, text)
    logger.info("Generated daily motivation for %s (%s)", day, source)
    return {"text": text, "source": source, "day": day}


async def get_daily_motivation(db: aiosqlite.Connection, tz: ZoneInfo) -> dict[str, Any]:
    day = datetime.now(tz).strftime("%Y-%m-%d")
    cached = await _cached_motivation(db, day)
    if cached:
        return {"text": cached, "source": "cache", "day": day}
    return {"text": pick("motivation_fallback"), "source": "fallback", "day": day}


async def get_roast_of_the_day(db: aiosqlite.Connection, tz: ZoneInfo) -> dict[str, Any]:
    return await get_daily_motivation(db, tz)


async def get_oracle(db: aiosqlite.Connection, tz: ZoneInfo) -> dict[str, Any]:
    week = datetime.now(tz).strftime("%Y-W%W")
    key = f"oracle:{week}"
    cached = await _get_cache(db, key)
    if cached:
        return {"text": cached, "source": "cache", "week": week}

    stats = await compute_stats(db)
    days_active = stats["days_active"]
    window = stats["compliance_window_days"]
    young_app = days_active < 90
    context = (
        f"App aktiv seit {days_active} Tag(en), erste Einnahme am {stats['first_day']}. "
        if young_app
        else ""
    )
    caveat = (
        "Die App ist noch jung — lange Streaks oder 90-Tage-Compliance sind noch nicht realistisch erreichbar. "
        "Bewerte nur die verfügbaren Daten, sei fair aber sarkastisch. "
        if young_app
        else ""
    )
    prompt = (
        f"Wöchentlicher Orakel-Report. {context}{caveat}"
        f"Streak: {stats['streak']} Tage. "
        f"Compliance über {window} Tag(e): {stats['compliance_percent']}%. "
        f"Genommen gesamt: {stats['total_taken']}."
    )
    text = await _call_openrouter(prompt, system=ORACLE_SYSTEM)
    if not text:
        if young_app:
            text = (
                f"Tag {days_active} deiner Medis-Karriere. "
                f"Streak: {stats['streak']}. Compliance ({window} Tage): {stats['compliance_percent']}%. "
                "Das Orakel ist beeindruckt — oder gelangweilt. Grenzwertig."
            )
        else:
            text = pick("streak", streak=stats["streak"]) + f" Compliance: {stats['compliance_percent']}%."
        source = "fallback"
    else:
        source = "ai"
    await _set_cache(db, key, text)

    return {"text": text, "source": source, "week": week}