import io
import smtplib
import ssl
from email.message import EmailMessage
from itsdangerous import URLSafeTimedSerializer
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
from config import Config


serializer = URLSafeTimedSerializer(Config.SECRET_KEY)


def generate_activation_token(email):
    return serializer.dumps(email, salt='account-activation')



def verify_activation_token(token, max_age=86400):
    return serializer.loads(token, salt='account-activation', max_age=max_age)



def send_mail(to_address, subject, body):
    msg = EmailMessage()
    msg['Subject'] = subject
    msg['From'] = Config.MAIL_SENDER
    msg['To'] = to_address
    msg.set_content(body)

    # SMTPS
    if Config.SMTP_PORT == 465:
        context = ssl.create_default_context()
        with smtplib.SMTP_SSL(Config.SMTP_SERVER, Config.SMTP_PORT, context=context) as server:
            if Config.SMTP_USERNAME:
                server.login(Config.SMTP_USERNAME, Config.SMTP_PASSWORD)
            server.send_message(msg)
        return

    # Normales SMTP, z. B. Port 25
    with smtplib.SMTP(Config.SMTP_SERVER, Config.SMTP_PORT) as server:
        if Config.MAIL_USE_TLS:
            server.starttls(context=ssl.create_default_context())

        if Config.SMTP_USERNAME:
            server.login(Config.SMTP_USERNAME, Config.SMTP_PASSWORD)

        server.send_message(msg)



def create_assessment_chart(labels, yes_counts, output_path):
    fig, ax = plt.subplots(figsize=(11, 5))
    x_values = list(range(len(labels)))

    ax.plot(x_values, yes_counts, marker='o')

    for x, y in zip(x_values, yes_counts):
        if y >= 7:
            color = 'green'
        elif y >= 4:
            color = 'orange'
        else:
            color = 'red'
        ax.scatter([x], [y], color=color, s=120)

    ax.set_xticks(x_values)
    ax.set_xticklabels(labels, rotation=20, ha='right')
    ax.set_ylim(0, 8)
    ax.set_ylabel('Anzahl JA-Antworten')
    ax.set_xlabel('Themen')
    ax.set_title('Assessment-Ergebnis')
    ax.grid(True, axis='y', alpha=0.3)
    fig.tight_layout()
    fig.savefig(output_path, dpi=150)
    plt.close(fig)



def create_chart_bytes(labels, yes_counts):
    buffer = io.BytesIO()
    fig, ax = plt.subplots(figsize=(11, 5))
    x_values = list(range(len(labels)))
    ax.plot(x_values, yes_counts, marker='o')
    for x, y in zip(x_values, yes_counts):
        if y >= 7:
            color = 'green'
        elif y >= 4:
            color = 'orange'
        else:
            color = 'red'
        ax.scatter([x], [y], color=color, s=120)
    ax.set_xticks(x_values)
    ax.set_xticklabels(labels, rotation=20, ha='right')
    ax.set_ylim(0, 8)
    ax.set_ylabel('Anzahl JA-Antworten')
    ax.set_xlabel('Themen')
    ax.set_title('Assessment-Ergebnis')
    ax.grid(True, axis='y', alpha=0.3)
    fig.tight_layout()
    fig.savefig(buffer, format='png', dpi=150)
    plt.close(fig)
    buffer.seek(0)
    return buffer