cv-site/internal/handlers/cv_contact.go

package handlers

import (
	"fmt"
	"log"
	"net/http"
	"strconv"
	"strings"
	"time"

	uimodel "github.com/juanatsap/cv-site/internal/models/ui"
)

// ==============================================================================
// CONTACT FORM SUBMISSION HANDLER
// Part of CVHandler - handles POST /api/contact
// ==============================================================================

// ContactFormData represents the contact form submission
type ContactFormData struct {
	Email        string
	Name         string
	Company      string
	Subject      string
	Message      string
	Website      string // Honeypot field - should be empty
	FormLoadedAt string // Timing field - Unix timestamp in milliseconds
	Lang         string
}

// HandleContact handles contact form submissions
func (h *CVHandler) HandleContact(w http.ResponseWriter, r *http.Request) {
	// Only accept POST requests
	if r.Method != http.MethodPost {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}

	// Parse form data
	if err := r.ParseForm(); err != nil {
		log.Printf("Error parsing contact form: %v", err)
		h.renderContactError(w, r, "Invalid form data. Please try again.")
		return
	}

	// Get language from query parameter
	lang := r.URL.Query().Get("lang")
	if lang == "" {
		lang = "en"
	}

	// Validate language
	if lang != "en" && lang != "es" {
		lang = "en"
	}

	// Extract form data
	formData := &ContactFormData{
		Email:        strings.TrimSpace(r.FormValue("email")),
		Name:         strings.TrimSpace(r.FormValue("name")),
		Company:      strings.TrimSpace(r.FormValue("company")),
		Subject:      strings.TrimSpace(r.FormValue("subject")),
		Message:      strings.TrimSpace(r.FormValue("message")),
		Website:      r.FormValue("website"),        // Honeypot
		FormLoadedAt: r.FormValue("form_loaded_at"), // Timing
		Lang:         lang,
	}

	// Validate form data (includes bot protection)
	if err := validateContactForm(formData, r); err != nil {
		log.Printf("Contact form validation failed from IP %s: %v", getClientIP(r), err)

		// Don't reveal specific errors to potential bots
		if strings.Contains(err.Error(), "spam detected") {
			// Silently succeed for bots
			h.renderContactSuccess(w, r, lang)
			return
		}

		h.renderContactError(w, r, err.Error())
		return
	}

	// Log the contact form submission (in production, send email or save to database)
	log.Printf("Contact form submission from %s (IP: %s)", formData.Email, getClientIP(r))
	log.Printf("  Name: %s, Company: %s", formData.Name, formData.Company)
	log.Printf("  Subject: %s", formData.Subject)
	log.Printf("  Message length: %d characters", len(formData.Message))

	// TODO: Implement actual email sending or database storage here
	// For now, we just log and return success

	// Render success response
	h.renderContactSuccess(w, r, lang)
}

// validateContactForm validates the contact form data and performs bot protection
func validateContactForm(data *ContactFormData, r *http.Request) error {
	// Bot protection: Honeypot check - website field should be empty
	if data.Website != "" {
		return fmt.Errorf("spam detected: honeypot field filled")
	}

	// Bot protection: Timing check - form should take at least 2 seconds to fill
	if data.FormLoadedAt != "" {
		loadedAt, err := strconv.ParseInt(data.FormLoadedAt, 10, 64)
		if err == nil {
			now := time.Now().UnixMilli()
			elapsed := now - loadedAt

			// Form filled too quickly (< 2 seconds) - likely a bot
			if elapsed < 2000 {
				return fmt.Errorf("spam detected: form filled too quickly (%dms)", elapsed)
			}

			// Form took too long (> 1 hour) - timestamp expired
			if elapsed > 3600000 {
				return fmt.Errorf("form session expired, please refresh and try again")
			}
		}
	}

	// Required field validation
	if data.Email == "" {
		return fmt.Errorf("email address is required")
	}

	if data.Message == "" {
		return fmt.Errorf("message is required")
	}

	// Email format validation (basic)
	if !strings.Contains(data.Email, "@") || !strings.Contains(data.Email, ".") {
		return fmt.Errorf("invalid email format")
	}

	// Message length validation
	if len(data.Message) < 10 {
		return fmt.Errorf("message is too short (minimum 10 characters)")
	}

	if len(data.Message) > 5000 {
		return fmt.Errorf("message is too long (maximum 5000 characters)")
	}

	return nil
}

// renderContactSuccess renders the contact success partial
func (h *CVHandler) renderContactSuccess(w http.ResponseWriter, r *http.Request, lang string) {
	// Load UI data for the specified language
	ui, err := uimodel.LoadUI(lang)
	if err != nil {
		log.Printf("Error loading UI data: %v", err)
		http.Error(w, "Internal server error", http.StatusInternalServerError)
		return
	}

	// Create template data
	data := map[string]interface{}{
		"UI":   ui,
		"Lang": lang,
	}

	// Render the success template
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	w.WriteHeader(http.StatusOK)

	tmpl, err := h.templates.Render("contact-success")
	if err != nil {
		log.Printf("Error loading contact success template: %v", err)
		// Fallback to simple HTML
		_, _ = w.Write([]byte(`<div class="contact-message contact-success">
			<iconify-icon icon="mdi:check-circle" width="24" height="24"></iconify-icon>
			<div class="contact-message-content">
				<strong>Message Sent!</strong>
				<p>Thank you for your message. I'll get back to you soon.</p>
			</div>
		</div>`))
		return
	}

	if err := tmpl.Execute(w, data); err != nil {
		log.Printf("Error rendering contact success template: %v", err)
		_, _ = w.Write([]byte(`<div class="contact-message contact-success">
			<iconify-icon icon="mdi:check-circle" width="24" height="24"></iconify-icon>
			<div class="contact-message-content">
				<strong>Message Sent!</strong>
				<p>Thank you for your message. I'll get back to you soon.</p>
			</div>
		</div>`))
	}
}

// renderContactError renders the contact error partial
func (h *CVHandler) renderContactError(w http.ResponseWriter, r *http.Request, errorMessage string) {
	// Get language from query parameter
	lang := r.URL.Query().Get("lang")
	if lang == "" {
		lang = "en"
	}

	// Validate language
	if lang != "en" && lang != "es" {
		lang = "en"
	}

	// Load UI data for the specified language
	ui, err := uimodel.LoadUI(lang)
	if err != nil {
		log.Printf("Error loading UI data: %v", err)
		http.Error(w, "Internal server error", http.StatusInternalServerError)
		return
	}

	// Create template data
	data := map[string]interface{}{
		"UI":           ui,
		"Lang":         lang,
		"ErrorMessage": errorMessage,
	}

	// Render the error template
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	w.WriteHeader(http.StatusBadRequest)

	tmpl, err := h.templates.Render("contact-error")
	if err != nil {
		log.Printf("Error loading contact error template: %v", err)
		// Fallback to simple HTML
		_, _ = w.Write([]byte(`<div class="contact-message contact-error">
			<iconify-icon icon="mdi:alert-circle" width="24" height="24"></iconify-icon>
			<div class="contact-message-content">
				<strong>Error</strong>
				<p>` + errorMessage + `</p>
			</div>
		</div>`))
		return
	}

	if err := tmpl.Execute(w, data); err != nil {
		log.Printf("Error rendering contact error template: %v", err)
		_, _ = w.Write([]byte(`<div class="contact-message contact-error">
			<iconify-icon icon="mdi:alert-circle" width="24" height="24"></iconify-icon>
			<div class="contact-message-content">
				<strong>Error</strong>
				<p>` + errorMessage + `</p>
			</div>
		</div>`))
	}
}

// Note: getClientIP is defined in contact.go