Form Handling and Data Processing

def form2dict(form) -> dict:
    """
    Convert FormData to dictionary.
    
    Processes multipart form data and URL-encoded form data
    into Python dictionary format for easy handling.
    
    Args:
        form: FormData object from HTTP request
        
    Returns:
        dict: Converted form data with string keys and values
    """

def fill_form(form, obj):
    """
    Fill form with data object.
    
    Populates form fields with values from an object,
    matching field names to object attributes.
    
    Args:
        form: HTML form element to populate
        obj: Object with data to fill form fields
        
    Returns:
        Form element with populated values
    """

def fill_dataclass(src, dest):
    """
    Fill dataclass from source object.
    
    Populates dataclass fields from source object attributes,
    useful for form data binding and validation.
    
    Args:
        src: Source object with data
        dest: Destination dataclass to populate
        
    Returns:
        Populated dataclass instance
    """

def find_inputs(form):
    """
    Find input elements in form.
    
    Scans form element tree to locate all input, select,
    and textarea elements for processing.
    
    Args:
        form: HTML form element to scan
        
    Returns:
        list: List of input elements found in form
    """

def File(*c, **kw):
    """
    Handle file uploads in forms.
    
    Creates file input element with proper multipart encoding
    and file handling capabilities.
    
    Args:
        *c: Child content (usually none for file inputs)
        **kw: Input attributes including:
            - name: Field name for form submission
            - accept: Allowed file types (e.g., '.jpg,.png,.pdf')
            - multiple: Allow multiple file selection
            - required: Make field required
            
    Returns:
        File input element with upload handling
    """

def Hidden(*c, **kw):
    """
    Hidden input field.
    
    Creates hidden input for storing form state and data
    that should not be visible to users.
    
    Args:
        *c: Content (usually none)
        **kw: Input attributes (name, value, etc.)
        
    Returns:
        Hidden input element
    """

def CheckboxX(*c, **kw):
    """
    Enhanced checkbox with label.
    
    Creates checkbox input with associated label
    for better accessibility and styling.
    
    Args:
        *c: Label content
        **kw: Input attributes and styling options
        
    Returns:
        Checkbox with label wrapper
    """

from fasthtml.common import *

app, rt = fast_app()

@rt('/contact')
def contact_form():
    return Titled("Contact Form",
        Form(
            Div(
                Label("Name:", for_="name"),
                Input(type="text", name="name", id="name", required=True),
                cls="form-group"
            ),
            Div(
                Label("Email:", for_="email"),
                Input(type="email", name="email", id="email", required=True),
                cls="form-group"
            ),
            Div(
                Label("Message:", for_="message"),
                Textarea(name="message", id="message", rows="5", required=True),
                cls="form-group"
            ),
            Button("Send Message", type="submit"),
            method="post",
            action="/contact/submit"
        )
    )

@rt('/contact/submit', methods=['POST'])
def submit_contact(request):
    # Convert form data to dictionary
    form_data = form2dict(await request.form())
    
    # Process the form data
    name = form_data.get('name', '')
    email = form_data.get('email', '')
    message = form_data.get('message', '')
    
    # Validate and save (simplified)
    if not all([name, email, message]):
        return Div("All fields are required", style="color: red;")
    
    # Save to database or send email here
    
    return Div(
        H2("Thank you!"),
        P(f"Thanks {name}, we received your message and will respond to {email} soon."),
        A("Send another message", href="/contact")
    )

from fasthtml.common import *

app, rt = fast_app()

@rt('/upload')
def upload_form():
    return Titled("File Upload",
        Form(
            Div(
                Label("Profile Picture:", for_="profile"),
                File(
                    name="profile",
                    id="profile",
                    accept=".jpg,.jpeg,.png,.gif",
                    required=True
                ),
                cls="form-group"
            ),
            Div(
                Label("Documents:", for_="documents"),
                File(
                    name="documents",
                    id="documents",
                    accept=".pdf,.doc,.docx,.txt",
                    multiple=True
                ),
                cls="form-group"
            ),
            Div(
                Label("Description:", for_="description"),
                Textarea(name="description", id="description", rows="3"),
                cls="form-group"
            ),
            Button("Upload Files", type="submit"),
            method="post",
            action="/upload/process",
            enctype="multipart/form-data"
        )
    )

@rt('/upload/process', methods=['POST'])
def process_upload(request):
    form = await request.form()
    form_data = form2dict(form)
    
    # Handle uploaded files
    files_info = []
    
    # Profile picture (single file)
    if 'profile' in form:
        profile_file = form['profile']
        if profile_file.filename:
            # Save file and get info
            filename = save_uploaded_file(profile_file, 'profiles')
            files_info.append(f"Profile: {filename}")
    
    # Documents (multiple files)
    if 'documents' in form:
        documents = form.getlist('documents')
        for doc in documents:
            if doc.filename:
                filename = save_uploaded_file(doc, 'documents')
                files_info.append(f"Document: {filename}")
    
    return Div(
        H2("Files Uploaded Successfully"),
        Ul(*[Li(info) for info in files_info]),
        P(f"Description: {form_data.get('description', 'None provided')}"),
        A("Upload more files", href="/upload")
    )

def save_uploaded_file(file, folder):
    """Helper function to save uploaded files"""
    import os
    import uuid
    
    # Create unique filename
    file_ext = os.path.splitext(file.filename)[1]
    unique_filename = f"{uuid.uuid4()}{file_ext}"
    
    # Save file (simplified - add proper error handling)
    save_path = f"uploads/{folder}/{unique_filename}"
    os.makedirs(os.path.dirname(save_path), exist_ok=True)
    
    with open(save_path, "wb") as f:
        f.write(file.file.read())
    
    return unique_filename

from fasthtml.common import *
from dataclasses import dataclass
from typing import Optional

@dataclass
class UserRegistration:
    username: str
    email: str
    password: str
    confirm_password: str
    newsletter: bool = False
    age: Optional[int] = None

app, rt = fast_app()

@rt('/register')
def registration_form(errors: dict = None):
    errors = errors or {}
    
    return Titled("User Registration",
        Form(
            Div(
                Label("Username:", for_="username"),
                Input(
                    type="text",
                    name="username",
                    id="username",
                    required=True,
                    hx_post="/validate/username",
                    hx_target="#username-error",
                    hx_trigger="blur"
                ),
                Div(id="username-error", 
                    errors.get('username', ''),
                    style="color: red;" if errors.get('username') else ""
                ),
                cls="form-group"
            ),
            Div(
                Label("Email:", for_="email"),
                Input(
                    type="email",
                    name="email",
                    id="email",
                    required=True,
                    hx_post="/validate/email",
                    hx_target="#email-error",
                    hx_trigger="blur"
                ),
                Div(id="email-error",
                    errors.get('email', ''),
                    style="color: red;" if errors.get('email') else ""
                ),
                cls="form-group"
            ),
            Div(
                Label("Password:", for_="password"),
                Input(type="password", name="password", id="password", required=True),
                Div(id="password-error",
                    errors.get('password', ''),
                    style="color: red;" if errors.get('password') else ""
                ),
                cls="form-group"
            ),
            Div(
                Label("Confirm Password:", for_="confirm_password"),
                Input(type="password", name="confirm_password", id="confirm_password", required=True),
                Div(id="confirm-password-error",
                    errors.get('confirm_password', ''),
                    style="color: red;" if errors.get('confirm_password') else ""
                ),
                cls="form-group"
            ),
            Div(
                Label("Age (optional):", for_="age"),
                Input(type="number", name="age", id="age", min="13", max="120"),
                cls="form-group"
            ),
            Div(
                Label(
                    CheckboxX(name="newsletter", value="yes"),
                    " Subscribe to newsletter"
                ),
                cls="form-group"
            ),
            Button("Register", type="submit"),
            method="post",
            action="/register/submit"
        )
    )

@rt('/validate/username', methods=['POST'])
def validate_username(username: str):
    if len(username) < 3:
        return Div("Username must be at least 3 characters", style="color: red;")
    elif username.lower() in ['admin', 'root', 'user', 'test']:
        return Div("Username not available", style="color: red;")
    else:
        return Div("✓ Username available", style="color: green;")

@rt('/validate/email', methods=['POST'])
def validate_email(email: str):
    import re
    email_pattern = r'^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$'
    
    if not re.match(email_pattern, email):
        return Div("Invalid email format", style="color: red;")
    else:
        return Div("✓ Email format valid", style="color: green;")

@rt('/register/submit', methods=['POST'])
def submit_registration(request):
    form_data = form2dict(await request.form())
    errors = {}
    
    # Validation
    if len(form_data.get('username', '')) < 3:
        errors['username'] = "Username must be at least 3 characters"
    
    if not form_data.get('email'):
        errors['email'] = "Email is required"
    
    password = form_data.get('password', '')
    confirm_password = form_data.get('confirm_password', '')
    
    if len(password) < 8:
        errors['password'] = "Password must be at least 8 characters"
    
    if password != confirm_password:
        errors['confirm_password'] = "Passwords do not match"
    
    # If validation fails, show form with errors
    if errors:
        return registration_form(errors)
    
    # Create user registration object
    registration = UserRegistration(
        username=form_data['username'],
        email=form_data['email'],
        password=form_data['password'],
        confirm_password=form_data['confirm_password'],
        newsletter=form_data.get('newsletter') == 'yes',
        age=int(form_data['age']) if form_data.get('age') else None
    )
    
    # Save registration (simplified)
    # save_user_registration(registration)
    
    return Div(
        H2("Registration Successful!"),
        P(f"Welcome {registration.username}!"),
        P(f"We've sent a confirmation email to {registration.email}"),
        A("Login", href="/login")
    )

from fasthtml.common import *

app, rt = fast_app(session_cookie='multistep')

@rt('/multistep')
def multistep_form(step: int = 1):
    session = request.session
    
    if step == 1:
        return step1_form()
    elif step == 2:
        return step2_form(session)
    elif step == 3:
        return step3_form(session)
    else:
        return Redirect('/multistep')

def step1_form():
    return Titled("Step 1: Personal Information",
        Form(
            H2("Personal Information"),
            Div(
                Label("First Name:", for_="first_name"),
                Input(type="text", name="first_name", required=True),
                cls="form-group"
            ),
            Div(
                Label("Last Name:", for_="last_name"),
                Input(type="text", name="last_name", required=True),
                cls="form-group"
            ),
            Div(
                Label("Date of Birth:", for_="birth_date"),
                Input(type="date", name="birth_date", required=True),
                cls="form-group"
            ),
            Button("Next", type="submit"),
            method="post",
            action="/multistep/step1"
        )
    )

@rt('/multistep/step1', methods=['POST'])
def process_step1(request):
    form_data = form2dict(await request.form())
    request.session['step1'] = form_data
    return Redirect('/multistep?step=2')

def step2_form(session):
    return Titled("Step 2: Contact Information",
        Form(
            H2("Contact Information"),
            P(f"Hello {session.get('step1', {}).get('first_name', 'there')}!"),
            Div(
                Label("Email:", for_="email"),
                Input(type="email", name="email", required=True),
                cls="form-group"
            ),
            Div(
                Label("Phone:", for_="phone"),
                Input(type="tel", name="phone"),
                cls="form-group"
            ),
            Div(
                Label("Address:", for_="address"),
                Textarea(name="address", rows="3"),
                cls="form-group"
            ),
            Div(
                Button("Previous", type="button", onclick="location.href='/multistep?step=1'"),
                Button("Next", type="submit"),
                cls="form-buttons"
            ),
            method="post",
            action="/multistep/step2"
        )
    )

@rt('/multistep/step2', methods=['POST'])
def process_step2(request):
    form_data = form2dict(await request.form())
    request.session['step2'] = form_data
    return Redirect('/multistep?step=3')

def step3_form(session):
    step1_data = session.get('step1', {})
    step2_data = session.get('step2', {})
    
    return Titled("Step 3: Review and Submit",
        Div(
            H2("Review Your Information"),
            
            H3("Personal Information"),
            P(f"Name: {step1_data.get('first_name', '')} {step1_data.get('last_name', '')}"),
            P(f"Date of Birth: {step1_data.get('birth_date', '')}"),
            
            H3("Contact Information"),
            P(f"Email: {step2_data.get('email', '')}"),
            P(f"Phone: {step2_data.get('phone', 'Not provided')}"),
            P(f"Address: {step2_data.get('address', 'Not provided')}"),
            
            Form(
                Div(
                    Label(
                        CheckboxX(name="terms", value="agreed", required=True),
                        " I agree to the terms and conditions"
                    ),
                    cls="form-group"
                ),
                Div(
                    Button("Previous", type="button", onclick="location.href='/multistep?step=2'"),
                    Button("Submit", type="submit"),
                    cls="form-buttons"
                ),
                method="post",
                action="/multistep/submit"
            )
        )
    )

@rt('/multistep/submit', methods=['POST'])
def submit_multistep(request):
    # Combine all form data
    step1_data = request.session.get('step1', {})
    step2_data = request.session.get('step2', {})
    
    # Process final submission
    complete_data = {**step1_data, **step2_data}
    
    # Save to database here
    
    # Clear session
    request.session.clear()
    
    return Div(
        H2("Submission Complete!"),
        P("Thank you for completing the form."),
        P("Your information has been saved successfully."),
        A("Start Over", href="/multistep")
    )