from pathlib import Path
from flask import Flask, flash, redirect, render_template, request, session, url_for, send_from_directory
from werkzeug.security import check_password_hash, generate_password_hash
from config import Config
from db import execute, execute_returning, fetch_all, fetch_one
from permissions import admin_required, login_required
from tools import create_assessment_chart, generate_activation_token, send_mail, verify_activation_token


app = Flask(__name__)
app.config.from_object(Config)
chart_dir = Path('generated_charts')
chart_dir.mkdir(exist_ok=True)


@app.context_processor
def inject_user():
    user = None
    is_admin = False
    if session.get('user_id'):
        user = fetch_one('SELECT id, name, email FROM benutzer WHERE id = %s', (session['user_id'],))
        admin_row = fetch_one(
            '''
            SELECT 1
            FROM benutzer_gruppen bg
            JOIN gruppen g ON g.id = bg.gruppen_id
            WHERE bg.benutzer_id = %s AND g.gruppenname = 'Admins'
            ''',
            (session['user_id'],),
        )
        is_admin = bool(admin_row)
    return {'current_user': user, 'is_admin': is_admin}


@app.route('/')
def index():
    if session.get('user_id'):
        return redirect(url_for('dashboard'))
    return render_template('index.html')


@app.route('/register', methods=['GET', 'POST'])
def register():
    if request.method == 'POST':
        name = request.form['name'].strip()
        email = request.form['email'].strip().lower()
        password = request.form['password']

        existing = fetch_one('SELECT id FROM benutzer WHERE email = %s', (email,))
        if existing:
            flash('E-Mail ist bereits registriert.', 'danger')
            return render_template('register.html')

        password_hash = generate_password_hash(password)
        execute(
            '''
            INSERT INTO benutzer (name, email, passwort_hash, is_active)
            VALUES (%s, %s, %s, FALSE)
            ''',
            (name, email, password_hash),
        )

        token = generate_activation_token(email)
        activation_link = f"{Config.APP_BASE_URL}{url_for('activate_account', token=token)}"
        send_mail(
            email,
            'Account aktivieren',
            f'Hallo {name},\n\nbitte aktiviere deinen Account:\n{activation_link}\n',
        )

        flash('Registrierung gespeichert. Bitte E-Mail zur Aktivierung prüfen.', 'success')
        return redirect(url_for('login'))
    return render_template('register.html')


@app.route('/activate/<token>')
def activate_account(token):
    try:
        email = verify_activation_token(token)
    except Exception:
        flash('Aktivierungslink ist ungültig oder abgelaufen.', 'danger')
        return redirect(url_for('login'))

    execute('UPDATE benutzer SET is_active = TRUE WHERE email = %s', (email,))
    flash('Account wurde aktiviert. Bitte anmelden.', 'success')
    return redirect(url_for('login'))


@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        email = request.form['email'].strip().lower()
        password = request.form['password']
        user = fetch_one('SELECT * FROM benutzer WHERE email = %s', (email,))

        if not user:
            flash('Ungültige Zugangsdaten.', 'danger')
            return render_template('login.html')
        if not user['is_active']:
            flash('Account ist noch nicht aktiviert.', 'warning')
            return render_template('login.html')

        stored_password = user['passwort_hash']
        password_ok = False
        if stored_password == 'topsecret' and password == 'topsecret':
            new_hash = generate_password_hash(password)
            execute('UPDATE benutzer SET passwort_hash = %s WHERE id = %s', (new_hash, user['id']))
            password_ok = True
        else:
            password_ok = check_password_hash(stored_password, password)

        if not password_ok:
            flash('Ungültige Zugangsdaten.', 'danger')
            return render_template('login.html')

        session['user_id'] = user['id']
        execute('UPDATE benutzer SET last_login = NOW() WHERE id = %s', (user['id'],))
        execute('INSERT INTO accesslog (userid) VALUES (%s)', (user['id'],))
        return redirect(url_for('dashboard'))
    return render_template('login.html')


@app.route('/logout')
def logout():
    session.clear()
    flash('Erfolgreich abgemeldet.', 'success')
    return redirect(url_for('login'))


@app.route('/dashboard')
@login_required
def dashboard():
    themen = fetch_all('SELECT * FROM thema ORDER BY id')
    return render_template('dashboard.html', themen=themen)


@app.route('/profil', methods=['GET', 'POST'])
@login_required
def profile():
    user = fetch_one('SELECT id, name, email FROM benutzer WHERE id = %s', (session['user_id'],))
    if request.method == 'POST':
        new_password = request.form['password']
        execute(
            'UPDATE benutzer SET passwort_hash = %s WHERE id = %s',
            (generate_password_hash(new_password), session['user_id'])
        )
        flash('Passwort wurde geändert.', 'success')
        return redirect(url_for('profile'))
    return render_template('profile.html', user=user)


@app.route('/thema/<int:thema_id>', methods=['GET', 'POST'])
@login_required
def topic(thema_id):
    thema = fetch_one('SELECT * FROM thema WHERE id = %s', (thema_id,))
    fragen = fetch_all('SELECT * FROM fragen WHERE themaid = %s ORDER BY id', (thema_id,))
    ansprechpartner = fetch_all(
        '''
        SELECT a.*
        FROM ansprechpartner a
        JOIN themaansprechpartner ta ON ta.ansprechpartnerid = a.id
        WHERE ta.themaid = %s
        ORDER BY a.name
        ''',
        (thema_id,),
    )

    if request.method == 'POST':
        assessment_id = request.form.get('assessment_id')
        if not assessment_id:
            assessment = execute_returning(
                'INSERT INTO assessment (userid) VALUES (%s) RETURNING id',
                (session['user_id'],),
            )
            assessment_id = assessment['id']

        for frage in fragen:
            value = request.form.get(f'frage_{frage["id"]}')
            if value not in ('ja', 'nein'):
                flash('Bitte alle Fragen beantworten.', 'warning')
                return render_template(
                    'topic.html',
                    thema=thema,
                    fragen=fragen,
                    ansprechpartner=ansprechpartner,
                    assessment_id=assessment_id,
                )
            execute(
                '''
                INSERT INTO assessmentanswer (assessmentid, themaid, frageid, antwort)
                VALUES (%s, %s, %s, %s)
                ON CONFLICT (assessmentid, frageid)
                DO UPDATE SET antwort = EXCLUDED.antwort
                ''',
                (assessment_id, thema_id, frage['id'], value == 'ja'),
            )

        next_topic = fetch_one('SELECT id FROM thema WHERE id > %s ORDER BY id LIMIT 1', (thema_id,))
        if next_topic:
            return redirect(url_for('topic', thema_id=next_topic['id'], assessment_id=assessment_id))
        return redirect(url_for('assessment_result', assessment_id=assessment_id))

    assessment_id = request.args.get('assessment_id', '')
    return render_template(
        'topic.html',
        thema=thema,
        fragen=fragen,
        ansprechpartner=ansprechpartner,
        assessment_id=assessment_id,
    )


@app.route('/assessment/<int:assessment_id>/result')
@login_required
def assessment_result(assessment_id):
    rows = fetch_all(
        '''
        SELECT t.kurztitel, COUNT(*) FILTER (WHERE aa.antwort = TRUE) AS ja_anzahl
        FROM thema t
        LEFT JOIN assessmentanswer aa ON aa.themaid = t.id AND aa.assessmentid = %s
        GROUP BY t.id, t.kurztitel
        ORDER BY t.id
        ''',
        (assessment_id,),
    )
    labels = [row['kurztitel'] for row in rows]
    values = [int(row['ja_anzahl']) for row in rows]
    filename = f'assessment_{assessment_id}.png'
    output_path = chart_dir / filename
    create_assessment_chart(labels, values, output_path)
    return render_template('result.html', assessment_id=assessment_id, chart_file=filename, rows=rows)


@app.route('/generated_charts/<path:filename>')
@login_required
def generated_chart(filename):
    return send_from_directory(chart_dir, filename)


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


@app.route('/admin/themen')
@admin_required
def admin_topics():
    themen = fetch_all('SELECT * FROM thema ORDER BY id')
    return render_template('admin/topics.html', themen=themen)


@app.route('/admin/fragen')
@admin_required
def admin_questions():
    fragen = fetch_all(
        '''SELECT f.id, f.text, t.kurztitel FROM fragen f JOIN thema t ON t.id = f.themaid ORDER BY t.id, f.id'''
    )
    return render_template('admin/questions.html', fragen=fragen)


@app.route('/admin/ansprechpartner')
@admin_required
def admin_contacts():
    contacts = fetch_all('SELECT * FROM ansprechpartner ORDER BY name')
    return render_template('admin/contacts.html', contacts=contacts)


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