"""Phase 3 coaching: preference generation + the weekly check-in coach.

Two distinct pieces:

- ``generate_preferences`` is DETERMINISTIC. Coaching preferences are a
  structural read of the person's Enneagram centre, so they are derived from a
  documented mapping (no LLM, fully testable). The user can override any field.

- ``CheckinCoach`` is the LLM piece. It writes a periodic check-in that quotes
  the person's OWN words and asks whether their stated direction still feels
  valid. Mirror, not compass: it asks, it never judges or prescribes.
"""
from typing import Any, Dict

from anthropic import AsyncAnthropic

DEFAULT_MODEL = "claude-sonnet-4-6"
MAX_TOKENS = 600

# Allowed values for each preference field (validated at the API boundary).
ALLOWED = {
    "coaching_frequency": {"weekly", "biweekly", "monthly", "off"},
    "coaching_style": {"direct", "warm", "reflective"},
    "misalignment_threshold": {"low", "medium", "high"},
    "friction_tolerance": {"low", "medium", "high"},
    "time_of_day_preference": {"morning", "afternoon", "evening"},
}

# Per-triad defaults. Rationale:
#   gut  — acts from instinct; wants it direct, tolerates friction, fewer
#          questions, a weekly nudge in the morning.
#   heart— navigates by feeling/connection; wants warmth, is sensitive to
#          drift (low threshold), prefers questions.
#   head — thinks before committing; wants reflective space, low friction
#          tolerance, questions over directives, a slower (biweekly) cadence.
_TRIAD_DEFAULTS = {
    "gut": {
        "coaching_frequency": "weekly",
        "coaching_style": "direct",
        "misalignment_threshold": "medium",
        "friction_tolerance": "high",
        "prefer_questions_over_directives": False,
        "time_of_day_preference": "morning",
    },
    "heart": {
        "coaching_frequency": "weekly",
        "coaching_style": "warm",
        "misalignment_threshold": "low",
        "friction_tolerance": "medium",
        "prefer_questions_over_directives": True,
        "time_of_day_preference": "morning",
    },
    "head": {
        "coaching_frequency": "biweekly",
        "coaching_style": "reflective",
        "misalignment_threshold": "medium",
        "friction_tolerance": "low",
        "prefer_questions_over_directives": True,
        "time_of_day_preference": "evening",
    },
}

# Used when the triad is missing/unknown: a gentle, question-led default that
# is consistent with mirror-not-compass.
_FALLBACK_DEFAULTS = {
    "coaching_frequency": "weekly",
    "coaching_style": "warm",
    "misalignment_threshold": "medium",
    "friction_tolerance": "medium",
    "prefer_questions_over_directives": True,
    "time_of_day_preference": "morning",
}


def generate_preferences(profile: Dict[str, Any]) -> Dict[str, Any]:
    """Derive default coaching preferences from a profile's Enneagram centre.

    Args:
        profile: at least ``{"triad": "gut"|"heart"|"head"|None}``.

    Returns:
        A dict with all six preference fields.
    """
    triad = (profile.get("triad") or "").lower()
    return dict(_TRIAD_DEFAULTS.get(triad, _FALLBACK_DEFAULTS))


class CheckinError(Exception):
    """Raised when check-in generation fails (API error or empty output)."""


SYSTEM_PROMPT = """You are an AI coach writing a brief, periodic check-in for a person using a self-discovery tool. You are a MIRROR, never a compass.

THE PERSON'S OWN WORDS (their profile):
{profile}

HOW THEY WANT TO BE COACHED:
{prefs}

RECENT WORK PATTERNS (from their time tracker, may be empty):
{work_patterns}

YOUR TASK:
- Write a short check-in (3-5 sentences) that QUOTES the person's own words back to them — a specific phrase from their goals or their sense of purpose, in quotation marks.
- If recent work patterns are given, you may gently reflect what they show (e.g. where their time has and hasn't gone) — but only as an observation to check against their own words. Never tell them it is good or bad.
- Then ask, gently and openly, whether that direction still feels true for them right now. Invite them to say if anything has shifted.

ABSOLUTE RULES (mirror, not compass):
- NEVER tell them what to do, whether they are on or off track, or what they "should" pursue. You ASK; you do not judge.
- NEVER invent goals or direction they did not state. Only reflect their own words.
- Do not mention Enneagram type numbers.
- Match their preferred style ({style}). If they prefer questions over directives ({prefer_questions}), lead with a question rather than a statement.
- Plain language, second person (you/your). No preamble, no sign-off, no markdown — just the check-in text."""


class CheckinCoach:
    """Generates the text of a single coaching check-in."""

    def __init__(self, api_key: str, model: str = DEFAULT_MODEL):
        if not api_key:
            raise CheckinError(
                "ANTHROPIC_API_KEY is not set; cannot generate a check-in."
            )
        self.model = model
        self.client = AsyncAnthropic(api_key=api_key)

    @staticmethod
    def _profile_block(profile: Dict[str, Any]) -> str:
        lines = [
            f"- What you love: {profile.get('love_summary') or '(none)'}",
            f"- What the world needs from you: {profile.get('mission_summary') or '(none)'}",
            f"- Where it converges: {profile.get('overlap_narrative') or '(none)'}",
            f"- Near-term goals: {profile.get('short_term_goals') or '(none stated)'}",
            f"- Long-term goals: {profile.get('long_term_goals') or '(none stated)'}",
        ]
        return "\n".join(lines)

    @staticmethod
    def _prefs_block(prefs: Dict[str, Any]) -> str:
        return (
            f"- style: {prefs.get('coaching_style')}\n"
            f"- prefers questions over directives: {prefs.get('prefer_questions_over_directives')}\n"
            f"- friction tolerance: {prefs.get('friction_tolerance')}"
        )

    async def generate(
        self,
        profile: Dict[str, Any],
        prefs: Dict[str, Any],
        work_patterns: str | None = None,
    ) -> str:
        """Produce the check-in body text. Raises CheckinError on failure.

        ``work_patterns`` is an optional plain-language summary of recent logged
        work (Phase 4); when present the coach may reflect it back as an
        observation to check against the person's own words."""
        system = SYSTEM_PROMPT.format(
            profile=self._profile_block(profile),
            prefs=self._prefs_block(prefs),
            work_patterns=work_patterns or "(no recent work logged)",
            style=prefs.get("coaching_style", "warm"),
            prefer_questions=prefs.get("prefer_questions_over_directives", True),
        )
        try:
            response = await self.client.messages.create(
                model=self.model,
                max_tokens=MAX_TOKENS,
                system=system,
                messages=[
                    {
                        "role": "user",
                        "content": "Write my check-in for this week.",
                    }
                ],
            )
            text = response.content[0].text.strip()
        except Exception as exc:  # noqa: BLE001 - surface any SDK/transport error
            raise CheckinError(f"Anthropic API call failed: {exc}") from exc

        if not text:
            raise CheckinError("Model returned an empty check-in.")
        return text