Hooks.on('renderTokenHUD', (app, html, data) => {
    const token = app.object;
    if (!token?.combatant) return;

    const viewedCombat = ui.combat?.viewed;
    if (!viewedCombat) return;

    // In Daggerheart, the combatant with the spotlight is the one whose turn it currently is.
    const hasSpotlight = viewedCombat.combatant?.id === token.combatant.id;

    // Determine icon and classes based on spotlight state
    const iconClass = hasSpotlight 
        ? "fa-solid fa-hand-sparkles dh-spotlight-glow" 
        : "fa-regular fa-hand-sparkles";
    
    const buttonHtml = `
        <div class="control-icon ${hasSpotlight ? 'active' : ''}" data-action="toggle-spotlight" title="Toggle Spotlight">
            <i class="${iconClass}"></i>
        </div>
    `;

    // Append to the right column of the Token HUD
    const colRight = html.find('.col.right');
    colRight.append(buttonHtml);

    // Add click listener
    html.find('[data-action="toggle-spotlight"]').click(async event => {
        event.preventDefault();
        event.stopPropagation();
        
        if (ui.combat && typeof ui.combat.setCombatantSpotlight === "function") {
            const btn = $(event.currentTarget);
            const icon = btn.find('i');
            const wasActive = btn.hasClass('active');
            
            // Optimistic UI update
            if (wasActive) {
                btn.removeClass('active');
                icon.removeClass('fa-solid dh-spotlight-glow').addClass('fa-regular');
            } else {
                btn.addClass('active');
                icon.removeClass('fa-regular').addClass('fa-solid dh-spotlight-glow');
            }

            // Call the system's spotlight toggle function
            await ui.combat.setCombatantSpotlight(token.combatant.id);
        } else {
            ui.notifications.warn("System does not support spotlight or combat is not initialized.");
        }
    });
});