"""LeoCRM - Minimal CRM with auth, companies, contacts."""
import os
import sqlite3
from datetime import datetime
from functools import wraps

from flask import Flask, render_template, request, redirect, url_for, flash, session, g
from werkzeug.security import generate_password_hash, check_password_hash

app = Flask(__name__)
app.secret_key = os.urandom(24).hex()
DATABASE = os.path.join(os.path.dirname(__file__), 'leocrm.db')


def get_db():
    if 'db' not in g:
        g.db = sqlite3.connect(DATABASE)
        g.db.row_factory = sqlite3.Row
        g.db.execute("PRAGMA foreign_keys = ON")
    return g.db


@app.teardown_appcontext
def close_db(exception):
    db = g.pop('db', None)
    if db is not None:
        db.close()


def init_db():
    db = sqlite3.connect(DATABASE)
    db.executescript('''
        CREATE TABLE IF NOT EXISTS users (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            username TEXT UNIQUE NOT NULL,
            password_hash TEXT NOT NULL,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
        );
        CREATE TABLE IF NOT EXISTS companies (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            name TEXT NOT NULL,
            address TEXT,
            phone TEXT,
            email TEXT,
            website TEXT,
            notes TEXT,
            user_id INTEGER NOT NULL,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
            FOREIGN KEY (user_id) REFERENCES users(id)
        );
        CREATE TABLE IF NOT EXISTS contacts (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            first_name TEXT NOT NULL,
            last_name TEXT NOT NULL,
            email TEXT,
            phone TEXT,
            position TEXT,
            notes TEXT,
            company_id INTEGER NOT NULL,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
            FOREIGN KEY (company_id) REFERENCES companies(id) ON DELETE CASCADE
        );
    ''')
    db.commit()
    db.close()


def login_required(f):
    @wraps(f)
    def decorated(*args, **kwargs):
        if 'user_id' not in session:
            flash('Bitte melde dich an.', 'warning')
            return redirect(url_for('login'))
        return f(*args, **kwargs)
    return decorated


@app.route('/')
def index():
    if 'user_id' in session:
        return redirect(url_for('dashboard'))
    return redirect(url_for('login'))


@app.route('/register', methods=['GET', 'POST'])
def register():
    if request.method == 'POST':
        username = request.form['username'].strip()
        password = request.form['password']
        if not username or not password:
            flash('Benutzername und Passwort sind erforderlich.', 'danger')
            return render_template('register.html')
        db = get_db()
        existing = db.execute('SELECT id FROM users WHERE username = ?', (username,)).fetchone()
        if existing:
            flash('Benutzername bereits vergeben.', 'danger')
            return render_template('register.html')
        db.execute('INSERT INTO users (username, password_hash) VALUES (?, ?)',
                   (username, generate_password_hash(password)))
        db.commit()
        flash('Registrierung erfolgreich! Bitte melde dich an.', 'success')
        return redirect(url_for('login'))
    return render_template('register.html')


@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        username = request.form['username'].strip()
        password = request.form['password']
        db = get_db()
        user = db.execute('SELECT * FROM users WHERE username = ?', (username,)).fetchone()
        if user and check_password_hash(user['password_hash'], password):
            session['user_id'] = user['id']
            session['username'] = user['username']
            flash(f'Willkommen, {username}!', 'success')
            return redirect(url_for('dashboard'))
        flash('Ungültige Anmeldedaten.', 'danger')
    return render_template('login.html')


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


@app.route('/dashboard')
@login_required
def dashboard():
    db = get_db()
    companies = db.execute(
        'SELECT * FROM companies WHERE user_id = ? ORDER BY name',
        (session['user_id'],)
    ).fetchall()
    return render_template('dashboard.html', companies=companies)


@app.route('/companies/create', methods=['GET', 'POST'])
@login_required
def company_create():
    if request.method == 'POST':
        db = get_db()
        db.execute('INSERT INTO companies (name, address, phone, email, website, notes, user_id) VALUES (?,?,?,?,?,?,?)',
                   (request.form['name'], request.form.get('address',''), request.form.get('phone',''),
                    request.form.get('email',''), request.form.get('website',''), request.form.get('notes',''),
                    session['user_id']))
        db.commit()
        flash('Firma erstellt.', 'success')
        return redirect(url_for('dashboard'))
    return render_template('company_form.html', company=None)


@app.route('/companies/<int:id>/edit', methods=['GET', 'POST'])
@login_required
def company_edit(id):
    db = get_db()
    company = db.execute('SELECT * FROM companies WHERE id = ? AND user_id = ?',
                         (id, session['user_id'])).fetchone()
    if not company:
        flash('Firma nicht gefunden.', 'danger')
        return redirect(url_for('dashboard'))
    if request.method == 'POST':
        db.execute('UPDATE companies SET name=?, address=?, phone=?, email=?, website=?, notes=? WHERE id=?',
                   (request.form['name'], request.form.get('address',''), request.form.get('phone',''),
                    request.form.get('email',''), request.form.get('website',''), request.form.get('notes',''), id))
        db.commit()
        flash('Firma aktualisiert.', 'success')
        return redirect(url_for('dashboard'))
    return render_template('company_form.html', company=company)


@app.route('/companies/<int:id>/delete', methods=['POST'])
@login_required
def company_delete(id):
    db = get_db()
    db.execute('DELETE FROM companies WHERE id = ? AND user_id = ?', (id, session['user_id']))
    db.commit()
    flash('Firma gelöscht.', 'info')
    return redirect(url_for('dashboard'))


@app.route('/companies/<int:company_id>/contacts')
@login_required
def contact_list(company_id):
    db = get_db()
    company = db.execute('SELECT * FROM companies WHERE id = ? AND user_id = ?',
                         (company_id, session['user_id'])).fetchone()
    if not company:
        flash('Firma nicht gefunden.', 'danger')
        return redirect(url_for('dashboard'))
    contacts = db.execute('SELECT * FROM contacts WHERE company_id = ? ORDER BY last_name, first_name',
                          (company_id,)).fetchall()
    return render_template('contact_list.html', company=company, contacts=contacts)


@app.route('/companies/<int:company_id>/contacts/create', methods=['GET', 'POST'])
@login_required
def contact_create(company_id):
    db = get_db()
    company = db.execute('SELECT * FROM companies WHERE id = ? AND user_id = ?',
                         (company_id, session['user_id'])).fetchone()
    if not company:
        flash('Firma nicht gefunden.', 'danger')
        return redirect(url_for('dashboard'))
    if request.method == 'POST':
        db.execute('INSERT INTO contacts (first_name, last_name, email, phone, position, notes, company_id) VALUES (?,?,?,?,?,?,?)',
                   (request.form['first_name'], request.form['last_name'], request.form.get('email',''),
                    request.form.get('phone',''), request.form.get('position',''), request.form.get('notes',''), company_id))
        db.commit()
        flash('Kontaktperson erstellt.', 'success')
        return redirect(url_for('contact_list', company_id=company_id))
    return render_template('contact_form.html', company=company, contact=None)


@app.route('/contacts/<int:id>/edit', methods=['GET', 'POST'])
@login_required
def contact_edit(id):
    db = get_db()
    contact = db.execute('''SELECT c.*, co.name as company_name, co.user_id
                            FROM contacts c JOIN companies co ON c.company_id = co.id
                            WHERE c.id = ? AND co.user_id = ?''',
                         (id, session['user_id'])).fetchone()
    if not contact:
        flash('Kontakt nicht gefunden.', 'danger')
        return redirect(url_for('dashboard'))
    if request.method == 'POST':
        db.execute('UPDATE contacts SET first_name=?, last_name=?, email=?, phone=?, position=?, notes=? WHERE id=?',
                   (request.form['first_name'], request.form['last_name'], request.form.get('email',''),
                    request.form.get('phone',''), request.form.get('position',''), request.form.get('notes',''), id))
        db.commit()
        flash('Kontakt aktualisiert.', 'success')
        return redirect(url_for('contact_list', company_id=contact['company_id']))
    return render_template('contact_form.html', company={'id': contact['company_id'], 'name': contact['company_name']}, contact=contact)


@app.route('/contacts/<int:id>/delete', methods=['POST'])
@login_required
def contact_delete(id):
    db = get_db()
    contact = db.execute('''SELECT c.company_id, co.user_id
                            FROM contacts c JOIN companies co ON c.company_id = co.id
                            WHERE c.id = ?''', (id,)).fetchone()
    if contact and contact['user_id'] == session['user_id']:
        db.execute('DELETE FROM contacts WHERE id = ?', (id,))
        db.commit()
        flash('Kontakt gelöscht.', 'info')
        return redirect(url_for('contact_list', company_id=contact['company_id']))
    flash('Kontakt nicht gefunden.', 'danger')
    return redirect(url_for('dashboard'))


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