use anyhow::Result;
use lettre::{
    message::{header::ContentType, Mailbox, MultiPart, SinglePart},
    transport::smtp::authentication::Credentials,
    AsyncSmtpTransport, AsyncTransport, Message, Tokio1Executor,
};
use std::collections::HashMap;
use std::env;

// ── Template Engine ───────────────────────────────────────────────────────────

pub struct TemplateEngine;

impl TemplateEngine {
    pub fn new() -> Self {
        Self
    }

    pub fn render(&self, template_name: &str, vars: HashMap<&str, &str>) -> Result<String> {
        let base = include_str!("../templates/base.html");
        let content = self.load_template(template_name)?;
        
        // Replace content in base template
        let mut html = base.replace("{{content}}", content);
        
        // Replace all variables
        for (key, value) in vars {
            html = html.replace(&format!("{{{{{}}}}}", key), value);
        }
        
        Ok(html)
    }

    fn load_template(&self, name: &str) -> Result<&str> {
        match name {
            // Auth & Account
            "welcome" => Ok(include_str!("../templates/welcome.html")),
            "verify-email" => Ok(include_str!("../templates/verify-email.html")),
            "password-reset" => Ok(include_str!("../templates/password-reset.html")),
            "password-changed" => Ok(include_str!("../templates/password-changed.html")),
            "account-suspended" => Ok(include_str!("../templates/account-suspended.html")),
            
            // Onboarding & Verification
            "onboarding-submitted" => Ok(include_str!("../templates/onboarding-submitted.html")),
            "profile-verified" => Ok(include_str!("../templates/profile-verified.html")),
            "profile-rejected" => Ok(include_str!("../templates/profile-rejected.html")),
            "documents-requested" => Ok(include_str!("../templates/documents-requested.html")),
            
            // Jobs
            "job-pending" => Ok(include_str!("../templates/job-pending.html")),
            "job-approved" => Ok(include_str!("../templates/job-approved.html")),
            "job-rejected" => Ok(include_str!("../templates/job-rejected.html")),
            "job-expired" => Ok(include_str!("../templates/job-expired.html")),
            
            // Applications
            "application-received" => Ok(include_str!("../templates/application-received.html")),
            "application-status" => Ok(include_str!("../templates/application-status.html")),
            
            // Requirements
            "requirement-pending" => Ok(include_str!("../templates/requirement-pending.html")),
            "requirement-approved" => Ok(include_str!("../templates/requirement-approved.html")),
            "requirement-expired" => Ok(include_str!("../templates/requirement-expired.html")),
            
            // Leads
            "new-lead-request" => Ok(include_str!("../templates/new-lead-request.html")),
            "lead-request-sent" => Ok(include_str!("../templates/lead-request-sent.html")),
            "lead-request-accepted" => Ok(include_str!("../templates/lead-request-accepted.html")),
            "lead-request-rejected" => Ok(include_str!("../templates/lead-request-rejected.html")),
            "lead-expired" => Ok(include_str!("../templates/lead-expired.html")),
            
            // Payments
            "payment-success" => Ok(include_str!("../templates/payment-success.html")),
            "invoice-generated" => Ok(include_str!("../templates/invoice-generated.html")),
            "manual-credit" => Ok(include_str!("../templates/manual-credit.html")),
            "credit-usage" => Ok(include_str!("../templates/credit-usage.html")),
            "low-credit-balance" => Ok(include_str!("../templates/low-credit-balance.html")),
            
            // Security
            "new-device-login" => Ok(include_str!("../templates/new-device-login.html")),
            
            // Support
            "support-ticket-created" => Ok(include_str!("../templates/support-ticket-created.html")),
            "support-ticket-replied" => Ok(include_str!("../templates/support-ticket-replied.html")),
            "support-ticket-resolved" => Ok(include_str!("../templates/support-ticket-resolved.html")),
            
            // Marketplace
            "new-matched-lead" => Ok(include_str!("../templates/new-matched-lead.html")),
            
            // Policy
            "policy-update" => Ok(include_str!("../templates/policy-update.html")),
            
            _ => Err(anyhow::anyhow!("Template not found: {}", name)),
        }
    }
}

impl Default for TemplateEngine {
    fn default() -> Self {
        Self::new()
    }
}

// ── Mailer ────────────────────────────────────────────────────────────────────

pub struct Mailer {
    transport: Option<AsyncSmtpTransport<Tokio1Executor>>,
    from_email: String,
    from_name: String,
    template_engine: TemplateEngine,
}

impl Mailer {
    pub fn new() -> Self {
        let smtp_host = env::var("SMTP_HOST").ok();
        let smtp_user = env::var("SMTP_USER").ok();
        let smtp_pass = env::var("SMTP_PASS").ok();
        let smtp_port: u16 = env::var("SMTP_PORT")
            .ok()
            .and_then(|p| p.parse().ok())
            .unwrap_or(587);

        let from_email = env::var("SMTP_FROM_EMAIL")
            .unwrap_or_else(|_| "noreply@nxtgauge.com".to_string());
        let from_name = env::var("SMTP_FROM_NAME")
            .unwrap_or_else(|_| "NXTGAUGE".to_string());

        let transport = match (smtp_host, smtp_user, smtp_pass) {
            (Some(host), Some(user), Some(pass)) => {
                let creds = Credentials::new(user, pass);
                match AsyncSmtpTransport::<Tokio1Executor>::starttls_relay(&host) {
                    Ok(builder) => {
                        let t = builder.port(smtp_port).credentials(creds).build();
                        tracing::info!("SMTP transport configured (host={} port={})", host, smtp_port);
                        Some(t)
                    }
                    Err(e) => {
                        tracing::warn!("SMTP transport init failed: {} — emails disabled", e);
                        None
                    }
                }
            }
            _ => {
                tracing::warn!("SMTP not configured — emails disabled");
                None
            }
        };

        Self {
            transport,
            from_email,
            from_name,
            template_engine: TemplateEngine::new(),
        }
    }

    async fn send_html(&self, to: &str, subject: &str, html_body: String) -> Result<()> {
        let Some(transport) = &self.transport else {
            tracing::debug!("SMTP disabled — skipping email to {}", to);
            return Ok(());
        };

        let from: Mailbox = format!("{} <{}>", self.from_name, self.from_email).parse()?;
        let to: Mailbox = to.parse()?;

        let email = Message::builder()
            .from(from)
            .to(to)
            .subject(subject)
            .header(ContentType::TEXT_HTML)
            .body(html_body)?;

        transport.send(email).await?;
        Ok(())
    }

    // ── Auth & Account ────────────────────────────────────────────────────────

    pub async fn send_verification_email(&self, to: &str, name: &str, otp: &str) -> Result<()> {
        let vars = HashMap::from([
            ("first_name", name),
            ("otp_code", otp),
        ]);
        let html = self.template_engine.render("verify-email", vars)?;
        self.send_html(to, "Verify Your Email Address", html).await
    }

    pub async fn send_password_reset_email(&self, to: &str, name: &str, token: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let reset_url = format!("{}/reset-password?token={}", frontend_url, token);
        
        let vars = HashMap::from([
            ("first_name", name),
            ("reset_url", &reset_url),
        ]);
        let html = self.template_engine.render("password-reset", vars)?;
        self.send_html(to, "Reset Your Password", html).await
    }

    pub async fn send_welcome_email(&self, to: &str, name: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let dashboard_url = format!("{}/dashboard", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", name),
            ("dashboard_url", &dashboard_url),
        ]);
        let html = self.template_engine.render("welcome", vars)?;
        self.send_html(to, "Welcome to Nxtgauge!", html).await
    }

    // ── Profile Verification ───────────────────────────────────────────────────

    pub async fn send_profile_verified_email(&self, to: &str, name: &str, role_name: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        
        let vars = HashMap::from([
            ("first_name", name),
            ("role_name", role_name),
            ("verified_at", &now),
            ("dashboard_url", &frontend_url),
        ]);
        let html = self.template_engine.render("profile-verified", vars)?;
        self.send_html(to, "Your Profile is Verified!", html).await
    }

    pub async fn send_profile_rejected_email(&self, to: &str, name: &str, role_name: &str, reason: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let profile_url = format!("{}/dashboard/profile", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", name),
            ("role_name", role_name),
            ("rejection_reason", reason),
            ("profile_url", &profile_url),
        ]);
        let html = self.template_engine.render("profile-rejected", vars)?;
        self.send_html(to, "Profile Verification Update", html).await
    }

    // ── Jobs ───────────────────────────────────────────────────────────────────

    pub async fn send_job_pending_email(&self, to: &str, company_name: &str, job_title: &str) -> Result<()> {
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        let vars = HashMap::from([
            ("first_name", company_name),
            ("job_title", job_title),
            ("posted_at", &now),
        ]);
        let html = self.template_engine.render("job-pending", vars)?;
        self.send_html(to, "Job Posted Successfully", html).await
    }

    pub async fn send_job_approved_email(&self, to: &str, company_name: &str, job_title: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        let expires = (chrono::Local::now() + chrono::Duration::days(30)).format("%B %d, %Y").to_string();
        let job_url = format!("{}/dashboard/jobs", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", company_name),
            ("job_title", job_title),
            ("approved_at", &now),
            ("expires_at", &expires),
            ("job_url", &job_url),
        ]);
        let html = self.template_engine.render("job-approved", vars)?;
        self.send_html(to, "Your Job is Now Live!", html).await
    }

    pub async fn send_job_rejected_email(&self, to: &str, company_name: &str, job_title: &str, reason: &str) -> Result<()> {
        let vars = HashMap::from([
            ("first_name", company_name),
            ("job_title", job_title),
            ("rejection_reason", reason),
        ]);
        let html = self.template_engine.render("job-rejected", vars)?;
        self.send_html(to, "Job Posting Needs Updates", html).await
    }

    pub async fn send_application_received_email(&self, to: &str, company_name: &str, job_title: &str, applicant_name: &str, total_apps: i64) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let apps_url = format!("{}/dashboard/jobs", frontend_url);
        let total_str = total_apps.to_string();
        
        let vars = HashMap::from([
            ("first_name", company_name),
            ("job_title", job_title),
            ("applicant_name", applicant_name),
            ("total_applications", &total_str),
            ("applications_url", &apps_url),
        ]);
        let html = self.template_engine.render("application-received", vars)?;
        self.send_html(to, &format!("New Application: {}", job_title), html).await
    }

    // ── Leads ──────────────────────────────────────────────────────────────────

    pub async fn send_lead_request_sent_email(&self, to: &str, name: &str, requirement_title: &str, location: &str, reserved: i32) -> Result<()> {
        let reserved_str = reserved.to_string();
        let vars = HashMap::from([
            ("first_name", name),
            ("requirement_title", requirement_title),
            ("location", location),
            ("tracecoins_reserved", &reserved_str),
        ]);
        let html = self.template_engine.render("lead-request-sent", vars)?;
        self.send_html(to, "Lead Request Sent", html).await
    }

    pub async fn send_lead_request_accepted_email(&self, to: &str, professional_name: &str, customer_name: &str, requirement_title: &str, deducted: i32) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        let lead_url = format!("{}/dashboard/leads/accepted", frontend_url);
        let deducted_str = deducted.to_string();
        
        let vars = HashMap::from([
            ("first_name", professional_name),
            ("customer_name", customer_name),
            ("requirement_title", requirement_title),
            ("tracecoins_deducted", &deducted_str),
            ("accepted_at", &now),
            ("lead_url", &lead_url),
        ]);
        let html = self.template_engine.render("lead-request-accepted", vars)?;
        self.send_html(to, "Lead Request Accepted!", html).await
    }

    pub async fn send_new_lead_request_email(&self, to: &str, customer_name: &str, requirement_title: &str, professional_name: &str, profession: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let now = chrono::Local::now().format("%B %d, %Y at %I:%M %p").to_string();
        let req_url = format!("{}/dashboard/requirements", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", customer_name),
            ("requirement_title", requirement_title),
            ("professional_name", professional_name),
            ("profession_type", profession),
            ("requested_at", &now),
            ("requirement_url", &req_url),
        ]);
        let html = self.template_engine.render("new-lead-request", vars)?;
        self.send_html(to, &format!("New Request: {}", requirement_title), html).await
    }

    // ── Payments ───────────────────────────────────────────────────────────────

    pub async fn send_payment_success_email(&self, to: &str, name: &str, package_name: &str, amount: i32, tracecoins: i32, transaction_id: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let invoice_url = format!("{}/dashboard/wallet/invoices", frontend_url);
        let wallet_url = format!("{}/dashboard/wallet", frontend_url);
        let amount_str = format!("{:.2}", amount as f32 / 100.0);
        let tc_str = tracecoins.to_string();
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        
        let vars = HashMap::from([
            ("first_name", name),
            ("package_name", package_name),
            ("amount_paid", &amount_str),
            ("tracecoins_amount", &tc_str),
            ("transaction_id", transaction_id),
            ("payment_date", &now),
            ("invoice_url", &invoice_url),
            ("wallet_url", &wallet_url),
        ]);
        let html = self.template_engine.render("payment-success", vars)?;
        self.send_html(to, "Payment Successful!", html).await
    }

    // ── Account ─────────────────────────────────────────────────────────────────

    pub async fn send_account_suspended_email(&self, to: &str, name: &str, reason: &str) -> Result<()> {
        let vars = HashMap::from([
            ("first_name", name),
            ("suspension_reason", reason),
        ]);
        let html = self.template_engine.render("account-suspended", vars)?;
        self.send_html(to, "Account Suspended", html).await
    }

    // ── Cron / Expiry ───────────────────────────────────────────────────────────

    pub async fn send_lead_expired_email(&self, to: &str, name: &str, tracecoins: i32) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let tc_str = tracecoins.to_string();
        let marketplace_url = format!("{}/dashboard/marketplace", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", name),
            ("tracecoins_returned", &tc_str),
            ("marketplace_url", &marketplace_url),
        ]);
        let html = self.template_engine.render("lead-expired", vars)?;
        self.send_html(to, "Lead Request Expired", html).await
    }

    pub async fn send_requirement_expired_email(&self, to: &str, name: &str, title: &str) -> Result<()> {
        let vars = HashMap::from([
            ("first_name", name),
            ("requirement_title", title),
        ]);
        let html = self.template_engine.render("requirement-expired", vars)?;
        self.send_html(to, "Requirement Expired", html).await
    }

    pub async fn send_job_expired_email(&self, to: &str, company_name: &str, title: &str) -> Result<()> {
        let vars = HashMap::from([
            ("first_name", company_name),
            ("job_title", title),
        ]);
        let html = self.template_engine.render("job-expired", vars)?;
        self.send_html(to, "Job Posting Expired", html).await
    }

    // ── Missing Methods Added ───────────────────────────────────────────────────

    pub async fn send_password_changed_email(&self, to: &str, name: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let now = chrono::Local::now().format("%B %d, %Y at %I:%M %p").to_string();
        let security_url = format!("{}/dashboard/settings", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", name),
            ("email", to),
            ("changed_at", &now),
            ("security_url", &security_url),
        ]);
        let html = self.template_engine.render("password-changed", vars)?;
        self.send_html(to, "Password Changed Successfully", html).await
    }

    pub async fn send_account_deleted_email(&self, to: &str, name: &str) -> Result<()> {
        let vars = HashMap::from([
            ("first_name", name),
        ]);
        // Use account-suspended template as base or create a simple message
        self.send_html(
            to, 
            "Account Deleted", 
            format!("<html><body><h1>Account Deleted</h1><p>Hi {},</p><p>Your account has been deleted.</p></body></html>", name)
        ).await
    }

    pub async fn send_approval_approved_email(&self, to: &str, name: &str, role: &str) -> Result<()> {
        self.send_profile_verified_email(to, name, role).await
    }

    pub async fn send_approval_rejected_email(&self, to: &str, name: &str, role: &str, reason: &str) -> Result<()> {
        self.send_profile_rejected_email(to, name, role, reason).await
    }

    pub async fn send_job_submitted_email(&self, to: &str, company_name: &str, job_title: &str) -> Result<()> {
        self.send_job_pending_email(to, company_name, job_title).await
    }

    pub async fn send_new_application_email(&self, to: &str, company_name: &str, job_title: &str, applicant_name: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let apps_url = format!("{}/dashboard/jobs", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", company_name),
            ("job_title", job_title),
            ("applicant_name", applicant_name),
            ("total_applications", "1"),
            ("applications_url", &apps_url),
        ]);
        let html = self.template_engine.render("application-received", vars)?;
        self.send_html(to, &format!("New Application: {}", job_title), html).await
    }

    pub async fn send_requirement_submitted_email(&self, to: &str, name: &str, title: &str) -> Result<()> {
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        
        let vars = HashMap::from([
            ("first_name", name),
            ("requirement_title", title),
            ("profession_type", "Service"),
            ("posted_at", &now),
        ]);
        let html = self.template_engine.render("requirement-pending", vars)?;
        self.send_html(to, "Requirement Submitted Successfully", html).await
    }

    pub async fn send_lead_accepted_customer_email(&self, to: &str, customer_name: &str, professional_name: &str, professional_email: &str, professional_phone: &str) -> Result<()> {
        let vars = HashMap::from([
            ("first_name", customer_name),
            ("professional_name", professional_name),
            ("professional_email", professional_email),
            ("professional_phone", professional_phone),
        ]);
        // Use a simple template or new-lead-request as base
        self.send_html(
            to,
            "Professional Contact Details",
            format!("<html><body><h1>Professional Contact</h1><p>Hi {},</p><p>You accepted {}'s request.</p><p>Email: {}</p><p>Phone: {}</p></body></html>",
                customer_name, professional_name, professional_email, professional_phone)
        ).await
    }

    pub async fn send_manual_credit_email(&self, to: &str, name: &str, amount: i32, reason: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let wallet_url = format!("{}/dashboard/wallet", frontend_url);
        let amount_str = amount.to_string();
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        
        let vars = HashMap::from([
            ("first_name", name),
            ("tracecoins_amount", &amount_str),
            ("credited_at", &now),
            ("reason", reason),
            ("wallet_url", &wallet_url),
        ]);
        let html = self.template_engine.render("manual-credit", vars)?;
        self.send_html(to, "Tracecoins Credited to Your Account", html).await
    }

    // ── Support Tickets ─────────────────────────────────────────────────────────

    pub async fn send_support_ticket_created_email(&self, to: &str, name: &str, ticket_id: &str, subject: &str, category: &str, priority: &str, response_time: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let ticket_url = format!("{}/dashboard/support/{}", frontend_url, ticket_id);
        
        let vars = HashMap::from([
            ("first_name", name),
            ("ticket_id", ticket_id),
            ("subject", subject),
            ("category", category),
            ("priority", priority),
            ("response_time", response_time),
            ("ticket_url", &ticket_url),
        ]);
        let html = self.template_engine.render("support-ticket-created", vars)?;
        self.send_html(to, "Support Ticket Received", html).await
    }

    pub async fn send_support_ticket_replied_email(&self, to: &str, name: &str, subject: &str, message: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let ticket_url = format!("{}/dashboard/support", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", name),
            ("subject", subject),
            ("latest_message", message),
            ("support_agent_name", "Nxtgauge Support Team"),
            ("ticket_url", &ticket_url),
        ]);
        let html = self.template_engine.render("support-ticket-replied", vars)?;
        self.send_html(to, "New Response on Your Ticket", html).await
    }

    pub async fn send_support_ticket_resolved_email(&self, to: &str, name: &str, subject: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        
        let vars = HashMap::from([
            ("first_name", name),
            ("subject", subject),
            ("resolved_at", &now),
            ("support_agent_name", "Nxtgauge Support Team"),
        ]);
        let html = self.template_engine.render("support-ticket-resolved", vars)?;
        self.send_html(to, "Ticket Resolved", html).await
    }

    // ── Documents Requested ─────────────────────────────────────────────────────

    pub async fn send_documents_requested_email(&self, to: &str, name: &str, role_name: &str, document_request: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let profile_url = format!("{}/dashboard/profile", frontend_url);
        
        let vars = HashMap::from([
            ("first_name", name),
            ("role_name", role_name),
            ("document_request", document_request),
            ("profile_url", &profile_url),
        ]);
        let html = self.template_engine.render("documents-requested", vars)?;
        self.send_html(to, "Additional Documents Required", html).await
    }

    // ── Application Status ──────────────────────────────────────────────────────

    pub async fn send_application_status_email(&self, to: &str, name: &str, job_title: &str, status: &str) -> Result<()> {
        let frontend_url = env::var("FRONTEND_URL").unwrap_or_else(|_| "https://nxtgauge.com".to_string());
        let apps_url = format!("{}/dashboard/applications", frontend_url);
        
        let (status_class, status_color, next_steps) = match status {
            "SHORTLISTED" => ("status-pending", "#d97706", "The employer has shortlisted you. They may contact you soon for an interview."),
            "INTERVIEW" => ("status-pending", "#d97706", "Congratulations! You've been selected for an interview. Check your email for scheduling details."),
            "OFFERED" => ("status-approved", "#059669", "Great news! You've received a job offer. Please review the offer details in your dashboard."),
            "HIRED" => ("status-approved", "#059669", "Congratulations on your new job! The employer will contact you with next steps."),
            "REJECTED" => ("status-rejected", "#dc2626", "Unfortunately, you were not selected for this position. Don't give up - apply to other jobs!"),
            _ => ("status-pending", "#6b7280", "Your application status has been updated."),
        };
        
        let now = chrono::Local::now().format("%B %d, %Y").to_string();
        
        let vars = HashMap::from([
            ("first_name", name),
            ("job_title", job_title),
            ("company_name", "The employer"),
            ("status", status),
            ("status_class", status_class),
            ("status_color", status_color),
            ("next_steps", next_steps),
            ("note", ""),
            ("updated_at", &now),
            ("applications_url", &apps_url),
        ]);
        let html = self.template_engine.render("application-status", vars)?;
        self.send_html(to, &format!("Application Update: {}", job_title), html).await
    }

    // ── Test Email ──────────────────────────────────────────────────────────────

    pub async fn send_test_email(&self, to: &str) -> Result<()> {
        let html = r##"<!DOCTYPE html>
<html>
<head>
    <style>
        body { font-family: Arial, sans-serif; margin: 0; padding: 20px; background: #f5f5f5; }
        .email-wrapper { max-width: 600px; margin: 0 auto; background: white; border-radius: 8px; overflow: hidden; }
        .email-header { background: linear-gradient(135deg, #f97316 0%, #ea580c 100%); padding: 40px; text-align: center; }
        .logo { color: white; font-size: 28px; font-weight: bold; }
        .email-content { padding: 40px; color: #374151; }
        .email-title { color: #111827; font-size: 24px; margin-bottom: 20px; }
        .success-box { background: #d1fae5; border-left: 4px solid #059669; padding: 20px; margin: 20px 0; }
    </style>
</head>
<body>
    <div class="email-wrapper">
        <div class="email-header">
            <div class="logo">NXT<span style="font-weight:300">GAUGE</span></div>
        </div>
        <div class="email-content">
            <h1 class="email-title">SMTP Test Successful! 🎉</h1>
            <p>Hi there,</p>
            <p>This is a test email to confirm that your SMTP configuration is working correctly.</p>
            
            <div class="success-box">
                <p style="margin: 0; color: #065f46;"><strong>✓ Your email settings are configured properly!</strong></p>
            </div>
            
            <p>If you received this email, it means:</p>
            <ul>
                <li>Your SMTP credentials are correct</li>
                <li>The mail server is accessible</li>
                <li>Emails can be sent successfully</li>
            </ul>
            
            <p>You're all set to start sending transactional emails to your users!</p>
            
            <p>Best regards,<br><strong>The Nxtgauge Team</strong></p>
        </div>
    </div>
</body>
</html>"##;
        
        self.send_html(to, "SMTP Test - Nxtgauge Email System", html.to_string()).await
    }
}

impl Default for Mailer {
    fn default() -> Self {
        Self::new()
    }
}