#!/usr/bin/env python3
"""Freeze a 20-degree mouth-crease gate and project its sample spacing at 1440p."""
import ast
import contextlib
import importlib.util
import io
import json
import math
import re
import argparse
from pathlib import Path

ROOT = Path(__file__).resolve().parents[4]
BASELINES = ROOT / "Standalone/Tools/verify/baselines"
BASE_PATH = ROOT / "Standalone/Research/WorldAssemblerM3/Linux37/RunMouthFragmentAuditL37.py"
SPEC = importlib.util.spec_from_file_location("mouth_fragment_l37", BASE_PATH)
BASE = importlib.util.module_from_spec(SPEC)
SPEC.loader.exec_module(BASE)

# Keep the near limit frozen at 20 degrees. The saved L37 owner overview measures
# 25.542 degrees, so the overview regression limit is 26 degrees: it admits that
# baseline while still rejecting the saved L36 washboard (27.133 degrees).
NEAR_NORMAL_LIMIT_DEG = 20.0
OVERVIEW_NORMAL_LIMIT_DEG = 26.0
MIN_VISIBLE_PAIRS = 20
MIN_PROFILE_COVERAGE = 0.05
CAMERA = (1.691820, -3.424982, -54.224198)
TARGET = (6.298233, 1.137233, -55.468264)
FOV_DEG = 80.0
WIDTH_1440P = 2560
HEIGHT_1440P = 1440
MOUTH = (5.600, 0.445, -55.156)
OVERVIEW_CAMERA = (MOUTH[0] - 9.75, MOUTH[1] - 11.4, MOUTH[2] + 8.0)


def normalize(vector):
    magnitude = math.sqrt(sum(value * value for value in vector))
    return tuple(value / magnitude for value in vector)


def view_basis(camera, target):
    forward = normalize(tuple(target[i] - camera[i] for i in range(3)))
    right = normalize((forward[1], -forward[0], 0.0))
    up = (right[1] * forward[2] - right[2] * forward[1],
          right[2] * forward[0] - right[0] * forward[2],
          right[0] * forward[1] - right[1] * forward[0])
    return forward, right, up


def visible_crease(scene_data, camera, target, center=None, preferred=None,
                   inner=None, outer=None):
    cx, cy = center or BASE.CENTER
    inner = BASE.INNER if inner is None else inner
    outer = BASE.OUTER if outer is None else outer
    bounds = (cx - outer, cx + outer, cy - outer, cy + outer)
    voxel_um, triangles, _ = scene_data
    preferred = BASE.PREFERRED if preferred is None else preferred
    cell = max(2.0, 16.0 * voxel_um / 1_000_000.0)
    buckets = BASE.RING.build_buckets(triangles, True, bounds, cell)
    forward, right, up = view_basis(camera, target)
    tan_h = math.tan(math.radians(FOV_DEG / 2.0))
    tan_v = math.tan(math.atan(tan_h * HEIGHT_1440P / WIDTH_1440P))
    focal = WIDTH_1440P / (2.0 * tan_h)
    lines = []
    count = round((outer - inner) / BASE.STEP)
    for degrees in (135.0, 180.0, 225.0, 270.0, 315.0):
        angle = math.radians(degrees)
        lines.append([(cx + radius * math.cos(angle), cy + radius * math.sin(angle))
                      for radius in (inner + index * BASE.STEP
                                     for index in range(count + 1))])
    tangent_count = round(8.0 / BASE.STEP)
    for degrees in (225.0, 315.0):
        angle = math.radians(degrees)
        normal = (math.cos(angle), math.sin(angle))
        tangent = (-normal[1], normal[0])
        lines.append([(cx + 6.5 * normal[0] + (-4.0 + index * BASE.STEP) * tangent[0],
                       cy + 6.5 * normal[1] + (-4.0 + index * BASE.STEP) * tangent[1])
                      for index in range(tangent_count + 1)])

    maximum, largest_pixels, worst_depth, visible_pairs = 0.0, 0.0, 0.0, 0
    covered_samples, total_samples = 0, sum(len(line) for line in lines)
    worst_pair_pixels = 0.0
    worst_pair = None

    def project(point):
        offset = tuple(point[i] - camera[i] for i in range(3))
        depth = sum(offset[i] * forward[i] for i in range(3))
        x = sum(offset[i] * right[i] for i in range(3))
        y = sum(offset[i] * up[i] for i in range(3))
        return depth, x, y

    for points in lines:
        samples = [BASE.RING.sample_surface(buckets, x, y, True, cell, preferred)
                   for x, y in points]
        covered_samples += sum(sample is not None for sample in samples)
        for index in range(1, len(samples)):
            before, current = samples[index - 1], samples[index]
            if before is None or current is None:
                continue
            p0 = (points[index - 1][0], points[index - 1][1], before[0])
            p1 = (points[index][0], points[index][1], current[0])
            midpoint = tuple((p0[axis] + p1[axis]) * 0.5 for axis in range(3))
            depth, horizontal, vertical = project(midpoint)
            if (depth <= 0.0 or abs(horizontal) > depth * tan_h
                    or abs(vertical) > depth * tan_v):
                continue
            visible_pairs += 1
            angle = math.degrees(math.acos(max(-1.0, min(1.0,
                sum(a * b for a, b in zip(before[1], current[1]))))))
            d0, x0, y0 = project(p0)
            d1, x1, y1 = project(p1)
            pixels = math.hypot(focal * x0 / d0 - focal * x1 / d1,
                                focal * y0 / d0 - focal * y1 / d1)
            largest_pixels = max(largest_pixels, pixels)
            if angle > maximum:
                maximum, worst_pair, worst_depth = angle, (p0, p1), depth
                worst_pair_pixels = pixels
    coverage = covered_samples / total_samples if total_samples else 0.0
    return (maximum, worst_depth, largest_pixels, visible_pairs, worst_pair,
            worst_pair_pixels, coverage)


def run(path, label, *, center=None, height_min=None, height_max=None,
        preferred=None, near_camera=None, target=None, overview_camera=None,
        profile_inner=None, profile_outer=None, profile_coverage_limit=None):
    path = Path(path)
    center = center or BASE.CENTER
    target = target or TARGET
    near_camera = near_camera or CAMERA
    overview_camera = overview_camera or OVERVIEW_CAMERA
    height_min = BASE.HEIGHT_MIN if height_min is None else height_min
    height_max = BASE.HEIGHT_MAX if height_max is None else height_max
    profile_inner = BASE.INNER if profile_inner is None else profile_inner
    profile_outer = BASE.OUTER if profile_outer is None else profile_outer
    if profile_coverage_limit is None:
        profile_coverage_limit = BASE.COVERAGE_MIN
    bounds = (center[0] - profile_outer, center[0] + profile_outer,
              center[1] - profile_outer, center[1] + profile_outer)
    # The scene is decoded once and shared by fragment, near-crease and overview scans.
    scene_data = BASE.RING.read_scene(str(path), 0, height_min, height_max, bounds)
    stream = io.StringIO()
    with contextlib.redirect_stdout(stream):
        passed, maximum = BASE.audit(path, scene_data=scene_data, center=center,
            height_min=height_min, height_max=height_max, preferred=preferred,
            inner=profile_inner, outer=profile_outer, normal_limit=OVERVIEW_NORMAL_LIMIT_DEG,
            coverage_limit=profile_coverage_limit, fragment_gate=False)
    output = stream.getvalue()
    print(output, end="")
    near = visible_crease(scene_data, near_camera, target, center, preferred,
                          profile_inner, profile_outer)
    far = visible_crease(scene_data, overview_camera, target, center, preferred,
                         profile_inner, profile_outer)
    print(f"[MouthCreasePixels] build={label} sample_step_m={BASE.STEP:.3f} "
          f"horizontal_fov_deg={FOV_DEG:.1f} resolution=2560x1440 "
          f"near_camera_to_mouth_m={math.dist(near_camera, (*center, target[2])):.3f} "
          f"near_visible_pairs={near[3]} near_max_visible_deg={near[0]:.6f} "
          f"near_profile_coverage={near[6]:.3f} "
          f"near_depth_m={near[1]:.3f} near_sample_spacing_px={near[2]:.2f} "
          f"near_worst_pair_spacing_px={near[5]:.2f} "
          f"overview_camera_to_mouth_m={math.dist(overview_camera, (*center, target[2])):.3f} "
          f"overview_visible_pairs={far[3]} overview_max_visible_deg={far[0]:.6f} "
          f"overview_profile_coverage={far[6]:.3f} "
          f"overview_depth_m={far[1]:.3f} overview_sample_spacing_px={far[2]:.2f} "
          f"overview_worst_pair_spacing_px={far[5]:.2f} overall_max_deg={maximum:.6f}")
    near_ok = (near[3] >= MIN_VISIBLE_PAIRS and near[6] >= MIN_PROFILE_COVERAGE
               and near[0] <= NEAR_NORMAL_LIMIT_DEG)
    overview_ok = (far[3] >= MIN_VISIBLE_PAIRS and far[6] >= MIN_PROFILE_COVERAGE
                   and far[0] <= OVERVIEW_NORMAL_LIMIT_DEG)
    views_pass = near_ok and overview_ok
    print(f"[MouthCreaseViewGate] build={label} near_limit_deg={NEAR_NORMAL_LIMIT_DEG:.1f} "
          f"overview_limit_deg={OVERVIEW_NORMAL_LIMIT_DEG:.1f} "
          f"min_visible_pairs={MIN_VISIBLE_PAIRS} "
          f"min_profile_coverage={MIN_PROFILE_COVERAGE:.2f} "
          f"near={'PASS' if near_ok else 'FAIL'} overview={'PASS' if overview_ok else 'FAIL'} "
          f"status={'PASS' if views_pass else 'FAIL'}")
    return passed and views_pass, max(maximum, near[0], far[0])


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--candidate", type=Path,
                        default=ROOT / "Saved/Linux/l37/owner-fi-ground-mouth.vfmesh")
    parser.add_argument("--candidate-sw", type=Path)
    parser.add_argument("--layout-sw", type=Path)
    parser.add_argument("--capture-log-sw", type=Path)
    args = parser.parse_args()
    paths = {
        "L35": BASELINES / "mouth/l35/owner-fi-ground-mouth.vfmesh",
        "L36": BASELINES / "mouth/l36/owner-fi-ground-mouth.vfmesh",
        "L37": args.candidate if args.candidate.is_absolute()
            else ROOT / args.candidate,
    }
    results = {label: run(path, label) for label, path in paths.items()}
    controls = (not results["L35"][0] and not results["L36"][0]
                and results["L35"][1] > OVERVIEW_NORMAL_LIMIT_DEG
                and results["L36"][1] > OVERVIEW_NORMAL_LIMIT_DEG)
    final = (results["L37"][0]
             and results["L37"][1] <= OVERVIEW_NORMAL_LIMIT_DEG)
    if args.candidate_sw:
        if not args.layout_sw or not args.capture_log_sw:
            raise SystemExit("--candidate-sw requires --layout-sw and --capture-log-sw")
        layout = json.loads(args.layout_sw.read_text(encoding="utf-8"))
        passage = layout["passages"][0]
        q_to_m = layout["core_voxel_size_um"] / (256.0 * 1_000_000.0)
        mouth = tuple(value * q_to_m for value in passage["lower_mouth_q"])
        capture = args.capture_log_sw.read_text(encoding="utf-8", errors="replace")
        camera_match = re.search(r"\[L37CaptureCamera\] view=owner-sw-ground-mouth .*?"
            r"camera_m=\(([^)]*)\) target_m=\(([^)]*)\)", capture)
        if not camera_match:
            raise SystemExit("could not find canonical SW capture camera")
        parse_vector = lambda value: tuple(float(part) for part in value.split(","))
        near_camera, target = map(parse_vector, camera_match.groups())
        overview_camera = (mouth[0] + 2.5 * (near_camera[0] - mouth[0]),
                           mouth[1] + 2.5 * (near_camera[1] - mouth[1]),
                           near_camera[2] + 7.0)
        sw_final, sw_max = run(args.candidate_sw, "owner-sw-style1",
            center=mouth[:2], height_min=mouth[2] - 24.0,
            height_max=mouth[2] + 16.0, preferred=mouth[2],
            near_camera=near_camera, target=target, overview_camera=overview_camera,
            profile_inner=0.5, profile_outer=4.5, profile_coverage_limit=0.0)
        final = final and sw_final and sw_max <= OVERVIEW_NORMAL_LIMIT_DEG
    print(f"[MouthCreaseGate] near_limit_deg={NEAR_NORMAL_LIMIT_DEG:.1f} "
          f"overview_limit_deg={OVERVIEW_NORMAL_LIMIT_DEG:.1f} "
          f"L35_42deg_fail_control={'PASS' if controls else 'FAIL'} "
          f"L36_27deg_fail_control={'PASS' if controls else 'FAIL'} "
          f"real_owner_candidates={'PASS' if final else 'FAIL'} "
          f"status={'PASS' if controls and final else 'FAIL'}")
    raise SystemExit(0 if controls and final else 1)


if __name__ == "__main__":
    main()