import os
import random
import time
import re
import psycopg2
from flask import Flask, render_template, request, jsonify
from difflib import SequenceMatcher

app = Flask(__name__)

def get_db_connection():
    max_retries = 10
    for i in range(max_retries):
        try:
            conn = psycopg2.connect(
                host=os.environ.get('DB_HOST', 'postgres-lat'),
                database=os.environ.get('DB_NAME', 'latein'),
                user=os.environ.get('DB_USER', 'latein'),
                password=os.environ.get('DB_PASS', 'latein')
            )
            return conn
        except psycopg2.OperationalError:
            time.sleep(2)
            continue
    raise Exception("DB Connection failed")

def init_db():
    conn = get_db_connection()
    cur = conn.cursor()
    if os.path.exists('init.sql'):
        with open('init.sql', 'r', encoding='utf-8') as f:
            cur.execute(f.read())
            conn.commit()
    cur.close()
    conn.close()

# Start-Initialisierung
init_db()

# --- HELPER FUNKTIONEN ---

def is_middle_relevant(text):
    if not text: return False
    signals = [' m', ' f', ' n', 'm.', 'f.', 'n.', 'pl', 'sg', 'gen', 'dat', 'akk', 'abl', 'perf', 'ppp']
    t = text.lower()
    ignore = ['adv', 'präp', 'konj', 'subj', 'interj']
    is_signal = any(s in t for s in signals)
    is_ignore = any(i in t for i in ignore)
    if is_ignore and not is_signal: return False
    return True

def clean_german_answers(text):
    text = re.sub(r'\(.*?\)', '', text)
    text = re.sub(r'\[.*?\]', '', text)
    parts = re.split(r'[;,]', text)
    return [p.strip() for p in parts if p.strip()]

def check_middle_logic(user_in, correct):
    """Prüft auf Unvollständigkeit (Komma-Trennung)"""
    u = user_in.strip().lower()
    c = correct.strip().lower()
    
    if u == c: return 'correct'
    
    def get_parts(s): return [x.strip() for x in s.split(',') if x.strip()]
    
    u_parts = get_parts(u)
    c_parts = get_parts(c)
    
    if not u_parts: return 'wrong'
    
    all_user_parts_correct = all(p in c_parts for p in u_parts)
    
    if all_user_parts_correct:
        if len(u_parts) < len(c_parts):
            return 'incomplete'
        return 'correct'
        
    ratio = SequenceMatcher(None, u, c).ratio()
    if ratio > 0.85: return 'typo'
    
    return 'wrong'

def check_string_match(user_in, correct):
    u = user_in.strip().lower()
    c = correct.strip().lower()
    if u == c: return 'correct'
    ratio = SequenceMatcher(None, u, c).ratio()
    if ratio > 0.85: return 'typo'
    return 'wrong'

# --- ROUTEN ---

@app.route('/')
def index():
    return render_template('index.html')

@app.route('/api/lessons')
def get_lessons():
    conn = get_db_connection()
    cur = conn.cursor()
    cur.execute("SELECT DISTINCT lesson FROM vocabulary")
    rows = cur.fetchall()
    cur.close()
    conn.close()
    
    lessons = [r[0] for r in rows]
    
    # Sortierung: Erst Zahlen, dann Strings, "Original" ganz hinten
    def sort_key(val):
        if val.isdigit(): return (0, int(val))
        if val.startswith("Original"): return (2, val)
        return (1, val)
        
    lessons.sort(key=sort_key)
    return jsonify(lessons)

@app.route('/api/question', methods=['POST'])
def get_question():
    data = request.json
    selected_lessons = data.get('lessons', [])
    ask_middle_setting = data.get('askMiddle', True)
    
    conn = get_db_connection()
    cur = conn.cursor()
    query = "SELECT id, lesson, latin, middle, german FROM vocabulary WHERE lesson = ANY(%s) ORDER BY RANDOM() LIMIT 1"
    cur.execute(query, (selected_lessons,))
    row = cur.fetchone()
    cur.close()
    conn.close()
    
    if not row: return jsonify({'error': 'Keine Vokabeln gefunden'})
        
    vid, lesson, latin, middle, german_raw = row
    german_answers = clean_german_answers(german_raw)
    
    middle_req = False
    hint = ""
    if middle:
        if ask_middle_setting and is_middle_relevant(middle):
            middle_req = True
        else:
            hint = middle 

    return jsonify({
        'id': vid,
        'latin': latin,
        'hint': hint,
        'middle_req': middle_req,
        'middle_correct': middle if middle_req else "",
        'german_count': len(german_answers),
        'german_correct': german_answers
    })

@app.route('/api/check', methods=['POST'])
def check():
    data = request.json
    inputs = data.get('inputs', []) 
    attempt_num = data.get('attempt', 1)
    
    results = []
    total_items = len(inputs)
    correct_items = 0
    has_incomplete = False
    
    for inp in inputs:
        user_val = inp.get('value', '')
        correct_val = inp.get('correct', '')
        field_type = inp.get('type', 'german') 
        
        status = 'wrong'
        
        if field_type == 'middle':
            status = check_middle_logic(user_val, correct_val)
        else:
            status = check_string_match(user_val, correct_val)
            
        res_entry = {'status': status, 'correct': correct_val}
        
        if status == 'incomplete':
            res_entry['msg'] = 'Unvollständig! Da fehlt noch etwas.'
            has_incomplete = True
        
        results.append(res_entry)
        
        if status in ['correct', 'typo']: 
            correct_items += 1
            
    score_fraction = 0
    if total_items > 0:
        base_score = correct_items / total_items
        if attempt_num > 1:
            base_score = base_score * 0.5
        score_fraction = base_score

    all_correct = (correct_items == total_items)

    return jsonify({
        'results': results,
        'all_correct': all_correct,
        'score': score_fraction,
        'has_incomplete': has_incomplete
    })

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)