Update app.py

app.py

@@ -97,6 +97,186 @@ def send_email(to, subject, html):
         return False
 
 
+def create_email_template(title, content, unsubscribe_link, email_type="reminder", problem_link=None, difficulty=None):
+    """Create a beautiful HTML email template"""
+    
+    # Color scheme based on email type
+    colors = {
+        "morning": {"primary": "#4CAF50", "secondary": "#81C784", "bg": "#E8F5E8"},
+        "afternoon": {"primary": "#FF9800", "secondary": "#FFB74D", "bg": "#FFF3E0"},
+        "night": {"primary": "#F44336", "secondary": "#EF5350", "bg": "#FFEBEE"},
+        "verification": {"primary": "#2196F3", "secondary": "#64B5F6", "bg": "#E3F2FD"}
+    }
+    
+    color = colors.get(email_type, colors["morning"])
+    
+    # Difficulty badge colors
+    difficulty_colors = {
+        "Easy": "#00B04F",
+        "Medium": "#FFA116", 
+        "Hard": "#FF375F"
+    }
+    
+    # Handle special cases for verification emails
+    if email_type == "verification":
+        problem_button = f"""
+        <div style="text-align: center; margin: 30px 0;">
+            <a href="{unsubscribe_link}" 
+               style="display: inline-block; background: linear-gradient(135deg, {color['primary']}, {color['secondary']}); 
+                      color: white; padding: 15px 30px; text-decoration: none; border-radius: 25px; 
+                      font-weight: bold; font-size: 16px; box-shadow: 0 4px 15px rgba(0,0,0,0.2); 
+                      transition: transform 0.2s;">
+                ✅ Verify Email
+            </a>
+        </div>
+        """
+        tips_section = ""
+        motivation_section = ""
+        difficulty_badge = ""
+    else:
+        # Use provided problem_link or construct from title
+        if problem_link:
+            link_url = problem_link
+        else:
+            link_url = f"https://leetcode.com/problems/{title.lower().replace(' ', '-').replace('.', '')}"
+            
+        # Add difficulty badge
+        if difficulty:
+            diff_color = difficulty_colors.get(difficulty, "#666")
+            difficulty_badge = f"""
+            <div style="text-align: center; margin: 10px 0;">
+                <span style="background-color: {diff_color}; color: white; padding: 4px 12px; 
+                           border-radius: 12px; font-size: 12px; font-weight: bold;">
+                    {difficulty}
+                </span>
+            </div>
+            """
+        else:
+            difficulty_badge = ""
+            
+        problem_button = f"""
+        <div style="text-align: center; margin: 30px 0;">
+            <a href="{link_url}" 
+               style="display: inline-block; background: linear-gradient(135deg, {color['primary']}, {color['secondary']}); 
+                      color: white; padding: 15px 30px; text-decoration: none; border-radius: 25px; 
+                      font-weight: bold; font-size: 16px; box-shadow: 0 4px 15px rgba(0,0,0,0.2); 
+                      transition: transform 0.2s;">
+                🚀 Solve Problem
+            </a>
+        </div>
+        """
+        
+        # Dynamic tips based on difficulty
+        if difficulty == "Easy":
+            tips_content = """
+                <li>Focus on understanding the problem clearly</li>
+                <li>Think about the simplest approach first</li>
+                <li>Test with the given examples</li>
+                <li>Consider edge cases like empty inputs</li>
+            """
+        elif difficulty == "Medium":
+            tips_content = """
+                <li>Break the problem into smaller subproblems</li>
+                <li>Consider multiple approaches (greedy, DP, etc.)</li>
+                <li>Think about time and space complexity</li>
+                <li>Use appropriate data structures</li>
+            """
+        else:  # Hard
+            tips_content = """
+                <li>Study similar problems and patterns</li>
+                <li>Don't rush - take time to understand</li>
+                <li>Consider advanced algorithms and techniques</li>
+                <li>Break it down step by step</li>
+            """
+            
+        tips_section = f"""
+        <!-- Tips Section -->
+        <div style="background-color: #f8f9fa; padding: 20px; border-radius: 8px; margin: 25px 0;">
+            <h3 style="color: #333; margin: 0 0 15px 0; font-size: 18px;">💡 {difficulty} Problem Tips</h3>
+            <ul style="color: #666; margin: 0; padding-left: 20px; line-height: 1.6;">
+                {tips_content}
+            </ul>
+        </div>
+        """
+        
+        motivation_quotes = [
+            "The expert in anything was once a beginner.",
+            "Every problem is a step forward in your journey.",
+            "Consistency beats perfection every time.",
+            "Code today, conquer tomorrow.",
+            "Small progress is still progress."
+        ]
+        import random
+        quote = random.choice(motivation_quotes)
+        
+        motivation_section = f"""
+        <!-- Stats or Motivation -->
+        <div style="text-align: center; padding: 20px; background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); border-radius: 8px; margin: 25px 0;">
+            <p style="color: white; margin: 0; font-size: 16px; font-style: italic;">
+                "{quote}" 💪
+            </p>
+        </div>
+        """
+    
+    return f"""
+    <!DOCTYPE html>
+    <html>
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
+        <title>LeetCode Daily Tracker</title>
+    </head>
+    <body style="margin: 0; padding: 0; font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f5f5f5;">
+        <div style="max-width: 600px; margin: 0 auto; background-color: white; box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);">
+            
+            <!-- Header -->
+            <div style="background: linear-gradient(135deg, {color['primary']}, {color['secondary']}); padding: 30px; text-align: center;">
+                <h1 style="color: white; margin: 0; font-size: 28px; font-weight: 300;">
+                    🧠 LeetCode Daily Tracker
+                </h1>
+                <p style="color: rgba(255,255,255,0.9); margin: 10px 0 0 0; font-size: 16px;">
+                    Your coding journey companion
+                </p>
+            </div>
+            
+            <!-- Content -->
+            <div style="padding: 40px 30px;">
+                <div style="background-color: {color['bg']}; border-left: 4px solid {color['primary']}; padding: 20px; margin-bottom: 25px; border-radius: 0 8px 8px 0;">
+                    {content}
+                    {difficulty_badge}
+                </div>
+                
+                {problem_button}
+                
+                {tips_section}
+                
+                {motivation_section}
+            </div>
+            
+            <!-- Footer -->
+            <div style="background-color: #f8f9fa; padding: 25px 30px; border-top: 1px solid #eee;">
+                <div style="text-align: center;">
+                    <p style="color: #666; margin: 0 0 15px 0; font-size: 14px;">
+                        Keep coding, keep growing! 🌱
+                    </p>
+                    <div style="margin: 15px 0;">
+                        <a href="https://leetcode.com" style="color: {color['primary']}; text-decoration: none; margin: 0 10px;">📊 LeetCode</a>
+                        <span style="color: #ccc;">|</span>
+                        <a href="https://github.com" style="color: {color['primary']}; text-decoration: none; margin: 0 10px;">💻 GitHub</a>
+                        <span style="color: #ccc;">|</span>
+                        <a href="{unsubscribe_link if email_type != 'verification' else '#'}" style="color: #999; text-decoration: none; margin: 0 10px; font-size: 12px;">{'Unsubscribe' if email_type != 'verification' else ''}</a>
+                    </div>
+                    <p style="color: #999; font-size: 12px; margin: 15px 0 0 0;">
+                        © 2024 LeetCode Daily Tracker. Made with ❤️ for coders.
+                    </p>
+                </div>
+            </div>
+        </div>
+    </body>
+    </html>
+    """
+
+
 # ================= VALIDATION =================
 
 EMAIL_REGEX = re.compile(
@@ -127,19 +307,42 @@ def valid_leetcode(username):
 # ================= LEETCODE =================
 
 def get_daily_problem():
+    try:
+        r = requests.get(f"{LEETCODE_API}/daily", timeout=10)
+        r.raise_for_status()
 
-    r = requests.get(f"{LEETCODE_API}/daily", timeout=10)
-    r.raise_for_status()
-
-    d = r.json()
-
-    if "questionTitle" in d:
-        return d["questionTitle"], d["titleSlug"]
-
-    if "title" in d:
-        return d["title"], d["titleSlug"]
-
-    raise Exception("Daily API invalid")
+        d = r.json()
+        print("📡 Daily API response keys:", list(d.keys()))
+
+        # Handle the current API format
+        if "questionTitle" in d and "titleSlug" in d:
+            title = d["questionTitle"]
+            slug = d["titleSlug"]
+            link = d.get("questionLink", f"https://leetcode.com/problems/{slug}/")
+            difficulty = d.get("difficulty", "Unknown")
+            print(f"✅ Found daily problem: {title} ({difficulty}) - {slug}")
+            return title, slug, link, difficulty
+
+        # Fallback for older format
+        if "title" in d and "titleSlug" in d:
+            title = d["title"] 
+            slug = d["titleSlug"]
+            link = f"https://leetcode.com/problems/{slug}/"
+            difficulty = d.get("difficulty", "Unknown")
+            print(f"✅ Found daily problem (fallback): {title} ({difficulty}) - {slug}")
+            return title, slug, link, difficulty
+
+        # If we can't find the expected fields, print the response
+        print("❌ Available fields in API response:", list(d.keys()))
+        raise Exception("Could not find title and slug in daily API response")
+
+    except requests.exceptions.RequestException as e:
+        print(f"❌ Network error calling daily API: {e}")
+        raise Exception(f"Failed to fetch daily problem: {e}")
+    
+    except json.JSONDecodeError as e:
+        print(f"❌ JSON decode error: {e}")
+        raise Exception("Invalid JSON response from daily API")
 
 
 def solved_today(username, slug):
@@ -213,9 +416,8 @@ def subscribe(username, email, timezone):
 
     row = cur.fetchone()
 
-    # Existing
+    # Existing user logic...
     if row:
-
         verified, token, unsub = row
 
         if verified and not unsub:
@@ -224,7 +426,6 @@ def subscribe(username, email, timezone):
             return "⚠️ Already subscribed"
 
         if verified and unsub:
-
             cur.execute("""
                 UPDATE users
                 SET unsubscribed=false,
@@ -238,24 +439,32 @@ def subscribe(username, email, timezone):
             conn.commit()
             cur.close()
             conn.close()
-
             return "✅ Re-subscribed"
 
-        # resend verify
-        link = f"{HF_URL}?verify={token}"
-
-        send_email(
-            email,
-            "Verify Subscription",
-            f"<a href='{link}'>Verify</a>"
+        # Resend verification with enhanced template
+        verification_content = f"""
+        <h2 style="color: #2196F3; margin: 0 0 15px 0;">Welcome back! 👋</h2>
+        <p style="color: #333; font-size: 16px; line-height: 1.6; margin: 0 0 15px 0;">
+            We're excited to have you on your coding journey again! 
+        </p>
+        <p style="color: #666; font-size: 14px; margin: 0;">
+            Click the verification button above to activate your daily LeetCode reminders.
+        </p>
+        """
+        
+        html_email = create_email_template(
+            "Email Verification", 
+            verification_content, 
+            f"{HF_URL}?verify={token}", 
+            "verification"
         )
 
+        send_email(email, "🔔 Please verify your email", html_email)
         cur.close()
         conn.close()
-
         return "📩 Verification re-sent"
 
-    # New
+    # New user - remove duplicate code
     token = uuid.uuid4().hex
 
     cur.execute("""
@@ -270,14 +479,33 @@ def subscribe(username, email, timezone):
     cur.close()
     conn.close()
 
-    link = f"{HF_URL}?verify={token}"
-
-    send_email(
-        email,
-        "Verify Subscription",
-        f"<a href='{link}'>Verify</a>"
+    # Welcome email with enhanced template
+    welcome_content = f"""
+    <h2 style="color: #4CAF50; margin: 0 0 15px 0;">Welcome to the club! 🎉</h2>
+    <p style="color: #333; font-size: 16px; line-height: 1.6; margin: 0 0 15px 0;">
+        You're about to embark on an amazing coding journey with daily LeetCode challenges!
+    </p>
+    <div style="background-color: white; border: 2px dashed #4CAF50; padding: 15px; border-radius: 8px; margin: 15px 0;">
+        <p style="color: #4CAF50; font-weight: bold; margin: 0 0 5px 0;">📅 Your Schedule:</p>
+        <p style="color: #666; font-size: 14px; margin: 0;">
+            🌅 <strong>9 AM</strong> - Daily problem<br>
+            🌆 <strong>3 PM</strong> - Gentle reminder<br>
+            🌙 <strong>8 PM</strong> - Final reminder
+        </p>
+    </div>
+    <p style="color: #666; font-size: 14px; margin: 0;">
+        Click the verification button above to start receiving your personalized reminders!
+    </p>
+    """
+    
+    html_email = create_email_template(
+        "Welcome", 
+        welcome_content, 
+        f"{HF_URL}?verify={token}", 
+        "verification"
     )
 
+    send_email(email, "🎯 Verify your LeetCode journey!", html_email)
     return "📩 Verification sent"
 
 
@@ -352,7 +580,6 @@ def handle_url(request: gr.Request):
         return ""
 
 
-# ================= SCHEDULER =================
 
 def run_scheduler(secret):
 
@@ -372,87 +599,194 @@ def run_scheduler(secret):
 
     users = cur.fetchall()
 
-    title, slug = get_daily_problem()
+    try:
+        title, slug, problem_link, difficulty = get_daily_problem()
+    except Exception as e:
+        cur.close()
+        conn.close()
+        return f"❌ Failed to get daily problem: {e}"
 
     now = datetime.now(pytz.utc)
-
     sent = 0
 
     for uid, user, mail, tz, last_d, last_s, token in users:
 
-        local = now.astimezone(pytz.timezone(tz))
-        h = local.hour
-
-        if 8 <= h <= 9:
-            slot="morning"; sub="Today's LeetCode"; body=f"<b>{title}</b>"
+        try:
+            local = now.astimezone(pytz.timezone(tz))
+            h = local.hour
+
+            # Enhanced email content based on time
+            if 8 <= h <= 9:
+                slot = "morning"
+                subject = f"🌅 Today's LeetCode Challenge: {title}"
+                content = f"""
+                <h2 style="color: #4CAF50; margin: 0 0 15px 0;">Good morning, coder! ☀️</h2>
+                <p style="color: #333; font-size: 18px; font-weight: bold; margin: 0 0 10px 0;">
+                    Today's Problem: <span style="color: #4CAF50;">{title}</span>
+                </p>
+                <p style="color: #666; font-size: 16px; line-height: 1.6; margin: 0;">
+                    Start your day with a fresh challenge! This {difficulty} problem is perfect for warming up 
+                    your coding muscles. Take your time to understand the requirements! 🚀
+                </p>
+                """
+                email_type = "morning"
+
+            elif 14 <= h <= 15:
+                slot = "afternoon"  
+                subject = f"⏰ Afternoon Coding Break: {title}"
+                content = f"""
+                <h2 style="color: #FF9800; margin: 0 0 15px 0;">Time for a coding break! ⚡</h2>
+                <p style="color: #333; font-size: 16px; margin: 0 0 15px 0;">
+                    Haven't tackled <strong style="color: #FF9800;">{title}</strong> yet? No worries!
+                </p>
+                <p style="color: #666; font-size: 16px; line-height: 1.6; margin: 0;">
+                    This {difficulty} problem is waiting for you. Sometimes a fresh afternoon perspective 
+                    can lead to breakthrough solutions! 💡
+                </p>
+                """
+                email_type = "afternoon"
+
+            elif 19 <= h <= 20:
+                slot = "night"
+                subject = f"🌙 Last Call: {title}"
+                content = f"""
+                <h2 style="color: #F44336; margin: 0 0 15px 0;">Final reminder! 🔥</h2>
+                <p style="color: #333; font-size: 16px; margin: 0 0 15px 0;">
+                    <strong style="color: #F44336;">{title}</strong> ({difficulty}) is still waiting for you!
+                </p>
+                <p style="color: #666; font-size: 16px; line-height: 1.6; margin: 0 0 15px 0;">
+                    Don't let the day end without giving it a try. Even reading through the problem 
+                    and thinking about approaches counts as progress! 
+                </p>
+                <div style="background-color: #fff3cd; border: 1px solid #ffeaa7; padding: 15px; border-radius: 8px;">
+                    <p style="color: #856404; margin: 0; font-size: 14px;">
+                        💪 <strong>Remember:</strong> Consistency beats perfection. Every attempt makes you stronger!
+                    </p>
+                </div>
+                """
+                email_type = "night"
+
+            else:
+                continue
 
-        elif 14 <= h <= 15:
-            slot="afternoon"; sub="Reminder"; body=f"Solve <b>{title}</b>"
+            today = date.today()
 
-        elif 19 <= h <= 20:
-            slot="night"; sub="Final Reminder"; body=f"Last chance <b>{title}</b>"
+            # Check if already sent today
+            if last_d == today and last_s == slot:
+                print(f"⏭️ Skipping {mail} - already sent {slot} email today")
+                continue
 
-        else:
-            continue
+            # Check if user already solved the problem
+            if solved_today(user, slug):
+                print(f"✅ {user} already solved {slug} - skipping email")
+                continue
 
-        today = date.today()
+            # Create beautiful HTML email with all enhancements
+            html_email = create_email_template(
+                title, 
+                content, 
+                f"{HF_URL}?unsubscribe={token}", 
+                email_type,
+                problem_link,
+                difficulty
+            )
 
-        if last_d == today and last_s == slot:
-            continue
+            ok = send_email(mail, subject, html_email)
 
-        if solved_today(user, slug):
-            continue
+            if not ok:
+                print(f"❌ Failed to send email to {mail}")
+                continue
 
-        unsub = f"{HF_URL}?unsubscribe={token}"
+            # Update database
+            cur.execute("""
+                UPDATE users
+                SET last_sent_date=%s,
+                    last_sent_slot=%s
+                WHERE id=%s
+            """, (today, slot, uid))
 
-        ok = send_email(
-            mail,
-            sub,
-            f"{body}<br><a href='{unsub}'>Unsubscribe</a>"
-        )
+            sent += 1
 
-        if not ok:
+        except Exception as e:
+            print(f"❌ Error processing user {user} ({mail}): {e}")
             continue
 
-        cur.execute("""
-            UPDATE users
-            SET last_sent_date=%s,
-                last_sent_slot=%s
-            WHERE id=%s
-        """, (today, slot, uid))
-
-        sent += 1
-
     conn.commit()
     cur.close()
     conn.close()
 
-    return f"✅ Scheduler completed. Sent: {sent}"
-
-
-# ================= UI =================
-
-with gr.Blocks(title="LeetCode Notifier") as app:
+    return f"✅ Scheduler completed. Sent: {sent} emails"
 
-    gr.Markdown("## 📬 LeetCode Daily Email Notifier")
 
-    u = gr.Textbox(label="Username")
-    m = gr.Textbox(label="Email")
-    tz = gr.Dropdown(pytz.all_timezones, value="Asia/Kolkata")
 
-    out = gr.Textbox(label="Status")
-
-    gr.Button("Subscribe").click(subscribe, [u, m, tz], out)
+# ================= UI =================
+with gr.Blocks(
+    title="LeetCode Notifier",
+    theme=gr.themes.Soft(),
+    css="""
+    .gradio-container {
+        max-width: 800px !important;
+        margin: auto !important;
+    }
+    """
+) as app:
+
+    gr.Markdown("""
+    # 📬 LeetCode Daily Email Notifier
+    
+    Get personalized daily LeetCode problem reminders sent directly to your inbox! 
+    Never miss a day of coding practice.
+    """)
 
-    gr.Markdown("### 🔒 Scheduler")
+    with gr.Row():
+        with gr.Column():
+            u = gr.Textbox(
+                label="🧑‍💻 LeetCode Username", 
+                placeholder="Enter your LeetCode username",
+                info="We'll verify this username exists on LeetCode"
+            )
+            m = gr.Textbox(
+                label="📧 Email Address", 
+                placeholder="your.email@gmail.com",
+                info="You'll receive a verification email"
+            )
+            tz = gr.Dropdown(
+                choices=sorted(pytz.all_timezones), 
+                value="Asia/Kolkata", 
+                label="🌍 Timezone",
+                info="Choose your timezone for proper scheduling"
+            )
+
+    with gr.Row():
+        subscribe_btn = gr.Button("🚀 Subscribe", variant="primary", scale=2)
+        
+    out = gr.Textbox(label="📝 Status", interactive=False, lines=2)
+    
+    subscribe_btn.click(subscribe, [u, m, tz], out)
+
+    gr.Markdown("""
+    ---
+    ### ⏰ Email Schedule
+    - **🌅 9:00 AM** - Daily problem notification
+    - **🌆 3:00 PM** - Gentle reminder (if not solved)
+    - **🌙 8:00 PM** - Final reminder (if not solved)
+    
+    ### 🔒 Admin Panel
+    """)
 
-    sec = gr.Textbox(type="password")
+    with gr.Row():
+        sec = gr.Textbox(
+            label="🔑 Secret Key", 
+            type="password", 
+            placeholder="Enter scheduler secret key"
+        )
+        run_btn = gr.Button("▶️ Run Scheduler", variant="secondary")
 
-    gr.Button("Run").click(run_scheduler, sec, out)
+    run_btn.click(run_scheduler, sec, out)
 
-    # ✅ URL handler
+    # URL handler for verification/unsubscribe
     app.load(handle_url, outputs=out)
 
 
 if __name__ == "__main__":
-    app.launch(debug=True)
+    app.launch(debug=True)