#!/usr/bin/env python3
"""Recupera In-Reply-To/References del .eml y recalcula threadId en Wino Mail.
Uso: python3 rethread2.py <bd.sqlite> <carpeta_mails>
"""
import sys, re, sqlite3, os, email

bd = sys.argv[1]
mails_dir = sys.argv[2]
conn = sqlite3.connect(bd)
cur = conn.cursor()

cur.execute("SELECT id, messageId FROM MailCopy")
rows = cur.fetchall()

# indexar emls por message-id en nombre de archivo
eml_by_mid = {}
for root, _, files in os.walk(mails_dir):
    for f in files:
        if not f.endswith(".eml"):
            continue
        # nombre base contiene el message-id antes de .eml
        base = f[:-4]
        eml_by_mid[base] = os.path.join(root, f)

def parse_headers(p):
    try:
        msg = email.message_from_bytes(open(p, "rb").read())
    except Exception:
        return None
    mid = msg.get("Message-ID", "")
    irt = msg.get("In-Reply-To", "")
    refs = msg.get("References", "")
    return mid, irt, refs

def thread_id(mid, irt, refs):
    if refs:
        m = re.search(r"<([^>]+)>", refs)
        return m.group(1) if m else refs.strip("<>")
    if irt:
        m = re.search(r"<([^>]+)>", irt)
        return m.group(1) if m else irt.strip("<>")
    if mid:
        m = re.search(r"<([^>]+)>", mid)
        return m.group(1) if m else mid.strip("<>")
    return ""

upd_thread = 0
upd_irt = 0
upd_refs = 0
not_found = 0
no_headers = 0

for rid, mid in rows:
    mid = (mid or "").strip()
    # buscar eml: por nombre base == mid, o mid contenido
    p = None
    if mid in eml_by_mid:
        p = eml_by_mid[mid]
    if p is None:
        # intentar coincidencia parcial (dominio distinto)
        mid_nodot = mid.split("@")[0][:20]
        for base, path in eml_by_mid.items():
            if mid_nodot and mid_nodot in base:
                p = path
                break
    if p is None:
        not_found += 1
        continue

    hdrs = parse_headers(p)
    if hdrs is None:
        not_found += 1
        continue
    emid, eirt, erefs = hdrs

    tid = thread_id(emid or mid, eirt, erefs)
    # guardar headers recuperados
    cur.execute("UPDATE MailCopy SET inReplyTo=?, \"references\"=?, threadId=? WHERE id=?",
                (eirt.strip() if eirt else "", erefs.strip() if erefs else "", tid or "", rid))
    if tid: upd_thread += 1
    if eirt.strip(): upd_irt += 1
    if erefs.strip(): upd_refs += 1

conn.commit()
print(f"correos: {len(rows)}")
print(f"eml no encontrados: {not_found}")
print(f"inReplyTo recuperado: {upd_irt}")
print(f"references recuperado: {upd_refs}")
print(f"threadId asignado: {upd_thread}")

# agrupar en hilos
print("\n=== hilos detectados (threadId con >1 correo) ===")
cur.execute("SELECT threadId, COUNT(*), MAX(sender) FROM MailCopy WHERE threadId!='' GROUP BY threadId HAVING COUNT(*)>1 ORDER BY COUNT(*) DESC LIMIT 15")
for row in cur.fetchall():
    print(row)
conn.close()