Hooks let your addon extend or modify Mumara Campaigns behavior without touching core files. Hook implementations live in the addon's hooks/ directory and are loaded by your service provider's boot() (typically a glob over hooks/*.php). There are two kinds: module hooks, which react to application events, and output hooks, which inject HTML into specific page locations.
You register a callback with add_hook('HookName', $priority, $callback). Module hooks include contact events (AddContact, EditContact, DeleteContact, ImportList), campaign events (StartBroadcast, CompleteBroadcast, EmailSentPostProcess), and tracking events (EmailOpened, LinkClicked, EmailBouncedPostProcess); some hooks let you return modified data. Output hooks like HeadEnd, BodyEnd, PrimaryMenu, and AlertBar return HTML strings, while addPageHtml can return an array with html, a CSS selector, and an action (prepend, append, before, after) for precise, route-conditional placement. Priority controls execution order — lower runs first (1-3 critical, 5-10 standard, 50+ logging/cleanup). Your addon can also define its own hooks for other addons via listen_hook() and run_hook_in_background(), and utilities like hook_exist(), hook_get(), and hook_get_all() query the registry.
Keep hook callbacks lightweight (dispatch heavy work to queued jobs), always return an empty string from output hooks when not applicable, return early when conditions don't match, and catch exceptions inside callbacks so a hook failure never breaks core flows.
