import spacy
import mysql.connector
import os
import sys
from collections import Counter
from string import punctuation

# === Load spaCy model ===
nlp = spacy.load("en_core_web_sm")

# === DB Credentials ===
DB_HOST = os.getenv("DB_HOST", "localhost")
DB_PORT = int(os.getenv("DB_PORT", 3306))
DB_USER = os.getenv("DB_USER", "emailuser")
DB_PASSWORD = os.getenv("DB_PASSWORD", "miguel33020")
DB_NAME = os.getenv("DB_NAME", "emailassistant")

# === Connect to DB ===
conn = mysql.connector.connect(
    host=DB_HOST,
    port=DB_PORT,
    user=DB_USER,
    password=DB_PASSWORD,
    database=DB_NAME
)
cursor = conn.cursor(dictionary=True)

# === Logging Helper ===
def log_event(cursor, level, source, message):
    cursor.execute(
        "INSERT INTO logs (level, source, message) VALUES (%s, %s, %s)",
        (level, source, message)
    )

# === Summarization Logic ===
def summarize(text, max_sentences=3):
    doc = nlp(text)
    words = [token.text.lower() for token in doc if token.is_alpha and not token.is_stop]
    word_freq = Counter(words)

    sentence_scores = {}
    for sent in doc.sents:
        for word in sent:
            if word.text.lower() in word_freq:
                sentence_scores[sent] = sentence_scores.get(sent, 0) + word_freq[word.text.lower()]

    summarized = sorted(sentence_scores, key=sentence_scores.get, reverse=True)[:max_sentences]
    return " ".join(str(s) for s in summarized)

# === Fetch All Emails with Missing Summaries ===
cursor.execute("SELECT id, body FROM emails WHERE ai_summary IS NULL")
emails = cursor.fetchall()

# === Main Processing Loop ===
for email in emails:
    email_id = email["id"]
    body = email["body"]

    if not body or not body.strip():
        log_event(cursor, "WARNING", "summarizer", f"Skipped empty body for email ID {email_id}")
        continue

    try:
        summary = summarize(body)
        if not summary.strip():
            summary = "No meaningful summary could be generated."

        # Optional confidence (ratio of summary length to original body)
        confidence = round(len(summary.split()) / max(1, len(body.split())), 2)

        # Update email
        cursor.execute("""
            UPDATE emails
            SET ai_summary = %s,
                ai_confidence = %s
            WHERE id = %s
        """, (summary, confidence, email_id))

        log_event(cursor, "INFO", "summarizer", f"Summarized email ID {email_id}")
        print(f"✅ Summarized email {email_id} (confidence: {confidence})")

    except Exception as e:
        log_event(cursor, "ERROR", "summarizer", f"Error summarizing email ID {email_id}: {str(e)}")
        print(f"❌ Error summarizing email {email_id}: {e}")

# === Commit & Close ===
conn.commit()
cursor.close()
conn.close()