#!/usr/bin/env python3
"""Script 50: publication-grade scoped inter-CPA anchor recompute.
Faithfully reproduces Script 45's any-pair five-way pool simulation
(max_cos & min_dh over a random same-size inter-CPA pool, excl. same-CPA),
then reports for scopes ABCD / BCD / BCD+nonBig4:
  - per-signature HC (D1) and HC+MC (D2) any-pair FAR
  - per-document HC (D1) and HC+MC (D2) any-pair FAR
  - per-firm per-document D2
ABCD is printed first to verify reproduction of published values
(per-sig HC~0.1102, per-doc D2~0.3375, Firm A~0.62). Read-only.
"""
import sqlite3
from collections import defaultdict
import numpy as np

DB = '/Volumes/NV2/PDF-Processing/signature-analysis/signature_analysis.db'
FIRM_A = '勤業眾信聯合'
BIG4 = ('勤業眾信聯合', '安侯建業聯合', '資誠聯合', '安永聯合')
ALIAS = {'勤業眾信聯合': 'A', '安侯建業聯合': 'B', '資誠聯合': 'C', '安永聯合': 'D'}
SEED = 42
POP = np.array([bin(i).count('1') for i in range(256)], dtype=np.uint8)


def wilson(k, n, z=1.96):
    if n == 0:
        return (None, None)
    p = k/n; d = 1+z*z/n
    c = (p+z*z/(2*n))/d
    h = z*np.sqrt(p*(1-p)/n+z*z/(4*n*n))/d
    return (max(0.0, c-h), min(1.0, c+h))


def load():
    conn = sqlite3.connect(f'file:{DB}?mode=ro', uri=True)
    cur = conn.cursor()
    cur.execute("""
        SELECT s.assigned_accountant, a.firm, s.source_pdf,
               s.feature_vector, s.dhash_vector
        FROM signatures s JOIN accountants a ON s.assigned_accountant=a.name
        WHERE s.assigned_accountant IS NOT NULL AND a.firm IS NOT NULL
          AND s.feature_vector IS NOT NULL AND s.dhash_vector IS NOT NULL""")
    rows = cur.fetchall()
    conn.close()
    return rows


def run(rows, keep_fn, label):
    keep = [r for r in rows if keep_fn(r[1])]
    n = len(keep)
    feats = np.stack([np.frombuffer(r[3], np.float32) for r in keep]).astype(np.float32)
    feats /= np.clip(np.linalg.norm(feats, axis=1, keepdims=True), 1e-9, None)
    dh = np.stack([np.frombuffer(r[4], np.uint8) for r in keep])
    cpas = np.array([r[0] for r in keep])
    firms = np.array([ALIAS.get(r[1], 'NonB4') for r in keep])
    docs = np.array([r[2] for r in keep])
    cpa_idx = defaultdict(list)
    for i, c in enumerate(cpas):
        cpa_idx[c].append(i)
    cpa_idx = {c: np.array(v) for c, v in cpa_idx.items()}
    pool_size = {c: len(v)-1 for c, v in cpa_idx.items()}
    rng = np.random.default_rng(SEED)
    max_cos = np.zeros(n, np.float32)
    min_dh = np.full(n, 64, np.int32)
    for si in range(n):
        c = cpas[si]; npool = pool_size[c]
        if npool <= 0:
            continue
        same = cpa_idx[c]
        draw = rng.integers(0, n, size=npool + same.size + 20)
        cand = draw[~np.isin(draw, same)][:npool]
        cosv = feats[cand] @ feats[si]
        dist = POP[dh[cand] ^ dh[si]].sum(axis=1)
        max_cos[si] = cosv.max()
        min_dh[si] = int(dist.min())
    # any-pair classification
    hc = (max_cos > 0.95) & (min_dh <= 5)
    mc = (max_cos > 0.95) & (min_dh > 5) & (min_dh <= 15)
    d1 = hc
    d2 = hc | mc
    print(f'\n===== {label} (n_sig={n:,}) =====')
    for nm, arr in [('per-sig HC (D1)', d1), ('per-sig HC+MC (D2)', d2)]:
        k = int(arr.sum()); lo, hi = wilson(k, n)
        print(f'  {nm}: {k/n:.4f} ({k}/{n}) [{lo:.4f},{hi:.4f}]')
    # per-document worst-case
    doc_d1 = defaultdict(bool); doc_d2 = defaultdict(bool); doc_firm = {}
    for i in range(n):
        if d1[i]: doc_d1[docs[i]] = True
        if d2[i]: doc_d2[docs[i]] = True
        doc_firm.setdefault(docs[i], firms[i])
        doc_d1.setdefault(docs[i], False); doc_d2.setdefault(docs[i], False)
    dl = list(doc_d2.keys())
    nd = len(dl)
    k1 = sum(doc_d1[d] for d in dl); k2 = sum(doc_d2[d] for d in dl)
    l1 = wilson(k1, nd); l2 = wilson(k2, nd)
    print(f'  per-doc HC (D1):   {k1/nd:.4f} ({k1}/{nd}) [{l1[0]:.4f},{l1[1]:.4f}]')
    print(f'  per-doc HC+MC (D2):{k2/nd:.4f} ({k2}/{nd}) [{l2[0]:.4f},{l2[1]:.4f}]')
    df = np.array([doc_firm[d] for d in dl])
    dv = np.array([doc_d2[d] for d in dl])
    for f in sorted(set(df)):
        m = df == f
        print(f'      Firm {f} per-doc D2: {dv[m].sum()/m.sum():.4f} ({int(dv[m].sum())}/{int(m.sum())})')


rows = load()
run(rows, lambda fm: fm in BIG4, 'ABCD (verify vs published: HC~0.110 / D2~0.338 / A~0.62)')
run(rows, lambda fm: fm in BIG4 and fm != FIRM_A, 'BCD-only')
run(rows, lambda fm: fm != FIRM_A, 'BCD + non-Big4')