# geometric_sanity.py - V1.0 (Geometric Sanity Engine)
# This module is the public entry point for the sanity check layer.
#
# Responsibilities:
# 1. Parse the raw DataAnchor dict into typed geometric objects.
# 2. Run all relevant constraint checks (via constraint_checks.py).
# 3. Build the "VERIFIED FACTS" prompt block for injection into the LLM prompt.
#
# Design note: All errors are caught and logged. This module NEVER raises —
# it always returns a valid (possibly empty) GeometryAnchor and prompt block.

import logging
from sympy import Rational, sympify

from geometry_types import Point, Line, Segment, Circle, GeometryAnchor
from constraint_checks import (
    check_point_on_circle,
    check_point_on_line,
    check_is_diameter,
    check_distance,
    find_circle_center_from_diameters,
)

logger = logging.getLogger(__name__)


def _parse_point(raw: str, name: str) -> Point | None:
    """
    Parses a string like '(3, 5)' or '3,5' into a Point with SymPy Rational coords.
    Returns None if unparseable (so the engine degrades gracefully).
    """
    try:
        clean = raw.strip().strip("()")
        parts = clean.split(",")
        if len(parts) != 2:
            return None
        x = Rational(parts[0].strip())
        y = Rational(parts[1].strip())
        return Point(name=name, x=x, y=y)
    except Exception as e:
        logger.debug(f"[GEO-SANITY] Could not parse point '{raw}' as '{name}': {e}")
        return None


def _parse_radius(raw) -> object | None:
    """
    Parses a radius value into a SymPy Rational or expression.
    """
    try:
        return Rational(raw)
    except Exception:
        try:
            return sympify(str(raw))
        except Exception as e:
            logger.debug(f"[GEO-SANITY] Could not parse radius '{raw}': {e}")
            return None


def _build_prompt_block(anchor: GeometryAnchor) -> str:
    """
    Builds the 'VERIFIED MATHEMATICAL FACTS' block to be injected before LLM generation.
    This is the final output consumed by prompts.py / strategy_manager.py.
    """
    facts_text = "\n".join(anchor.verified_facts) if anchor.verified_facts else "אין עובדות מאומתות."
    warnings_text = "\n".join(anchor.warnings) if anchor.warnings else "אין סתירות."
    
    block = f"""
╔══════════════════════════════════════════════════════╗
║  VERIFIED MATHEMATICAL FACTS (GROUND TRUTH — V1.0)  ║
╚══════════════════════════════════════════════════════╝
{facts_text}

╔══════════════════════════════════════════════════════╗
║  CONSTRAINT VIOLATIONS (READ CAREFULLY)             ║
╚══════════════════════════════════════════════════════╝
{warnings_text}

⚠️ הוראה קריטית: אם האינטואיציה שלך סותרת עובדה מאומתת לעיל,
   **העובדה האלגברית תמיד מנצחת**. אל תמציא נתונים גיאומטריים
   שאינם מאושרים כ-Verified Fact. כל ה-Verified Facts חושבו ע"י
   SymPy ואינם ניתנים לערעור.
╔══════════════════════════════════════════════════════╝
"""
    return block


def run_geometric_sanity(data_anchor: dict) -> tuple[GeometryAnchor, str]:
    """
    V1.0: Main entry point. Parses the data_anchor dict and runs all applicable checks.
    
    Args:
        data_anchor: dict — the raw anchor extracted by orchestrator._extract_key_data()
    
    Returns:
        (GeometryAnchor, str) — the populated anchor + the prompt block for LLM injection.
    
    This function NEVER raises. All exceptions are caught and logged.
    """
    anchor = GeometryAnchor()

    if not data_anchor:
        logger.info("[GEO-SANITY] Empty data_anchor — skipping geometric checks.")
        return anchor, ""

    logger.info("[GEO-SANITY] 🔍 Starting Geometric Sanity Check...")

    # ─── 1. Parse raw center & radius ───────────────────────────────────────────
    raw_center = data_anchor.get("center")
    raw_radius = data_anchor.get("radius")
    circle = None

    if raw_center and len(raw_center) == 2:
        try:
            cx = Rational(raw_center[0])
            cy = Rational(raw_center[1])
            center_point = Point(name="O", x=cx, y=cy)
        except Exception as e:
            center_point = None
            logger.warning(f"[GEO-SANITY] Could not parse center {raw_center}: {e}")
    else:
        center_point = None

    if center_point and raw_radius is not None:
        r = _parse_radius(raw_radius)
        if r is not None:
            circle = Circle(center=center_point, radius=r)
            anchor.circles.append(circle)
            anchor.add_fact(f"✓ מעגל נטען: מרכז {center_point}, r={r}")

    # ─── 2. Parse named points ────────────────────────────────────────────────
    parsed_points: dict[str, Point] = {}

    for field_name in ["point_a", "point_b", "point_c", "point_d"]:
        raw = data_anchor.get(field_name)
        if raw:
            label = field_name.split("_")[-1].upper()
            pt = _parse_point(str(raw), label)
            if pt:
                parsed_points[label] = pt
                anchor.points.append(pt)

    # Also parse points from the 'points' list (e.g., ["A(3,5)", "B(0,0)"])
    for raw_point_str in data_anchor.get("points", []):
        try:
            # Match "A(3,5)" or "A(3, 5)"
            import re
            m = re.match(r'([A-Za-z]+)\s*\(([^)]+)\)', str(raw_point_str))
            if m:
                lbl = m.group(1)
                coords = m.group(2).split(",")
                if len(coords) == 2:
                    px = Rational(coords[0].strip())
                    py = Rational(coords[1].strip())
                    pt = Point(name=lbl, x=px, y=py)
                    parsed_points[lbl] = pt
                    anchor.points.append(pt)
        except Exception as e:
            logger.debug(f"[GEO-SANITY] Could not parse points entry '{raw_point_str}': {e}")

    # ─── 3. Run point-on-circle checks ───────────────────────────────────────
    if circle:
        for name, pt in parsed_points.items():
            check_point_on_circle(pt, circle, anchor)

    # ─── 4. Diameter check: if exactly 2 points, check if they form a diameter ─
    if circle and len(parsed_points) >= 2:
        names = list(parsed_points.keys())
        for i in range(len(names)):
            for j in range(i + 1, len(names)):
                p_i = parsed_points[names[i]]
                p_j = parsed_points[names[j]]
                seg = Segment(p1=p_i, p2=p_j)
                check_is_diameter(seg, circle, anchor)
                anchor.segments.append(seg)

    # ─── 5. Final summary log ─────────────────────────────────────────────────
    logger.info(
        f"[GEO-SANITY] ✅ Check complete. "
        f"Facts: {len(anchor.verified_facts)}, Warnings: {len(anchor.warnings)}"
    )

    prompt_block = _build_prompt_block(anchor)
    return anchor, prompt_block


def build_verified_facts_prompt(anchor: GeometryAnchor) -> str:
    """
    Public helper: Re-builds the prompt block from an already-populated anchor.
    Useful for re-injection after additional checks.
    """
    return _build_prompt_block(anchor)