Developer Reference

Technical reference for developers extending or integrating with Super Speedy Emails.

Last updated for DB version 2.5.0 / plugin version 1.05. If get_option( 'sse_db_version' ) reports a higher number, this doc may be behind.

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Database Tables

All tables use the WordPress prefix (e.g. wp_sse_lists). Schema changes go through SSE_Activator::create_tables() via dbDelta.

Phase 1 tables (signup / forms / subscription management)

sse_lists

Column	Type	Description
id	bigint(20) unsigned	Primary key
name	varchar(255)	List name
slug	varchar(255)	URL-friendly slug (unique)
description	text	Optional description
status	varchar(20)	active or archived
settings	longtext	JSON for misc settings
requires_confirmation	tinyint(1)	Double opt-in flag (default 1) — Phase 2B
is_newsletter	tinyint(1)	1 = this list is the article-newsletter audience (single-select)
category	varchar(40)	Email category this list maps to (list_broadcast default) — Phase 2C
created_at / updated_at	datetime

sse_subscribers

Column	Type	Description
id	bigint(20) unsigned	Primary key
email	varchar(255)	Email address (unique)
first_name / last_name	varchar(255)
wp_user_id	bigint(20) unsigned	Linked WordPress user ID (nullable)
cookie_id	varchar(64)	Guest identification cookie value
ip_address	varchar(45)	IP at time of subscription
status	varchar(20)	pending / active / bounced / complained / suppressed — Phase 2A
confirmed_at	datetime	Double opt-in confirmation timestamp — Phase 2B
marketing_opted_out_at	datetime	When marketing-opt-out happened
marketing_opt_out_reason	varchar(64)	user_request / complaint / bounce / migrated_unsubscribed
digest_frequency	varchar(20)	instant / digest — Phase 2C
unsubscribe_token	varchar(64)	Long random token for one-click unsubscribe URLs
source	varchar(64)	form / migration_mailpoet / migration_mailerlite / wc_purchase / admin
created_at / updated_at	datetime

sse_subscriber_lists

Column	Type	Description
id	bigint(20) unsigned	Primary key
subscriber_id	bigint(20) unsigned	FK to sse_subscribers
list_id	bigint(20) unsigned	FK to sse_lists
status	varchar(20)	subscribed, unsubscribed, or pending
subscribed_at	datetime
unsubscribed_at	datetime	nullable

Unique on (subscriber_id, list_id).

sse_forms

Column	Type	Description
id	bigint(20) unsigned	Primary key
name	varchar(255)	Internal form name
list_ids	longtext	JSON array of list IDs
fields	longtext	JSON: {"first_name": true, "last_name": false}
style	longtext	JSON: preset, colors, border radius, button text
popup_settings	longtext	JSON popup config (null if not a popup)
success_message	text
status	varchar(20)	active or inactive
created_at / updated_at	datetime

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Phase 2 tables (sending pipeline)

sse_suppressions

The authoritative do-not-send store. Scopes: global, marketing, category:<term_id>, list:<list_id>, product_marketing:<product_id>.

Column	Type	Description
id	bigint(20) unsigned	Primary key
email	varchar(255)	Normalized lowercase
scope	varchar(80)	See above
reason	varchar(64)	user_unsubscribe / complaint / bounce_hard / bounce_soft_repeated / manual / migrated
source	varchar(64)	Where the suppression came from
created_at	datetime

Unique on (email, scope).

sse_newsletter_prefs

Per-subscriber, per-category preferences. Missing rows mean defaulted-in.

Column	Type	Description
id	bigint(20) unsigned	Primary key
subscriber_id	bigint(20) unsigned	FK to sse_subscribers
term_id	bigint(20) unsigned	WP term_id of a top-level post category
subscribed	tinyint(1)	1 = wants this category
updated_at	datetime

Unique on (subscriber_id, term_id).

sse_campaigns

Column	Type	Description
id	bigint(20) unsigned	Primary key
name	varchar(255)	Internal name
category	varchar(40)	See Email Categories
type	varchar(20)	broadcast / automation_step / digest
subject	varchar(255)
from_name / from_email / reply_to	varchar(255)	Optional per-campaign overrides
body_text	longtext	Plain-text body (with merge tags)
body_html	longtext	HTML body (optional; auto-generated when omitted)
audience_query	longtext	JSON segment query — see Segments
audience_snapshot	longtext	Frozen recipient list at sending transition
automation_id	bigint(20) unsigned	FK to sse_automations (null for broadcasts)
schedule_at	datetime	nullable
status	varchar(20)	draft / scheduled / sending / sent / cancelled
sent_at	datetime
recipient_count	int unsigned	Frozen count from snapshot
created_at / updated_at	datetime

sse_automations

Column	Type	Description
id	bigint(20) unsigned	Primary key
name	varchar(255)
trigger_type	varchar(40)	wc_product_purchased / manual / custom (via filter)
trigger_config	longtext	JSON, e.g. { "product_ids": [...], "match": "any" }
category	varchar(40)	Email category for all steps
status	varchar(20)	active / paused
created_at / updated_at	datetime

sse_automation_steps

Ordered steps for an automation. Cumulative offsets from enrolment timestamp.

Column	Type	Description
id	bigint(20) unsigned	Primary key
automation_id	bigint(20) unsigned	FK
position	int unsigned	Sort order (0-indexed)
offset_days / offset_hours	int	Cumulative offset from enrollment_created_at
subject	varchar(255)
body_text	longtext
body_html	longtext
created_at / updated_at	datetime

Index on (automation_id, position).

sse_automation_enrollments

Column	Type	Description
id	bigint(20) unsigned	Primary key
automation_id	bigint(20) unsigned	FK
subscriber_id	bigint(20) unsigned	FK
context	longtext	JSON, e.g. { "order_id": 123, "product_id": 456 }
context_hash	varchar(32)	md5 of dedup-relevant context (e.g. order_id)
current_step	int unsigned	Position of the next step to send
next_send_at	datetime	When the current step is due
status	varchar(20)	active / complete / cancelled
created_at / updated_at	datetime

Unique on (automation_id, subscriber_id, context_hash). Index on (next_send_at, status).

sse_email_log

One row per attempted send. Drives reporting + compliance audit trail.

Column	Type	Description
id	bigint(20) unsigned	Primary key
subscriber_id	bigint(20) unsigned	nullable for fully ad-hoc
email	varchar(255)	Captured at send-time
campaign_id / automation_id	bigint(20) unsigned	nullable
category	varchar(40)	Denormalised for fast filtering
legal_basis	varchar(40)	consent / legitimate_interest / service
subject	varchar(255)
mailgun_message_id	varchar(255)
status	varchar(20)	queued / sent / delivered / bounced / complained / failed
opened_at / clicked_at / bounced_at / complained_at / unsubscribed_at / delivered_at	datetime	First-event timestamps
open_count / click_count	int unsigned	Cumulative counters
error	text	Provider error text
context	longtext	JSON merge-data snapshot
source_plugin / source_reference	varchar	For 3rd-party integrations (e.g. ssp-product-renewals / renewal:order:123)
test_mode	varchar(20)	live / log_only / redirect
created_at / updated_at	datetime

Indexes: (subscriber_id, created_at), (campaign_id, status), mailgun_message_id, category, test_mode.

sse_email_events

Raw event stream from MailGun webhooks. Append-only.

Column	Type	Description
id	bigint(20) unsigned	Primary key
email_log_id	bigint(20) unsigned	FK (nullable — events can arrive before match)
mailgun_message_id	varchar(255)
event	varchar(40)	delivered / opened / clicked / unsubscribed / complained / permanent_fail / temporary_fail
payload	longtext	Full webhook payload (JSON)
occurred_at	datetime	From the webhook payload
received_at	datetime	When we received it

sse_email_queue

Cron-drained send queue. Small (rows live only while pending).

Column	Type	Description
id	bigint(20) unsigned	Primary key
email_log_id	bigint(20) unsigned	FK — log row is created up-front
priority	int	Lower = sooner (transactional 1, marketing 10)
attempts	int unsigned
next_attempt_at	datetime	Exponential backoff (1m → 4m → 16m → 64m → 256m)
locked_by	varchar(64)	Worker ID
locked_until	datetime
last_error	text
created_at	datetime

sse_product_owners

Derived cache populated from completed/processing WC orders. Bundle expansion applied at write time.

Column	Type	Description
id	bigint(20) unsigned	Primary key
subscriber_id	bigint(20) unsigned	FK
product_id	bigint(20) unsigned	The resolved product (direct line item OR bundle component)
direct	tinyint(1)	1 = bought it directly, 0 = via a bundle
first_purchased_at / last_purchased_at	datetime

Unique on (subscriber_id, product_id, direct).

sse_confirmation_tokens

Double opt-in tokens. 7-day TTL.

Column	Type	Description
id	bigint(20) unsigned	Primary key
token	varchar(64)	Unique
subscriber_id	bigint(20) unsigned	FK
list_ids	longtext	JSON array of list IDs being confirmed
form_id	bigint(20) unsigned	nullable
expires_at	datetime
consumed_at	datetime	nullable
created_at	datetime

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PHP Classes

Phase 1

SSE_Lists

SSE_Lists::create( array $data ): int|WP_Error
SSE_Lists::get( int $id ): object|null
SSE_Lists::get_all( array $args ): array
SSE_Lists::count( array $args ): int
SSE_Lists::update( int $id, array $data ): bool|WP_Error
SSE_Lists::delete( int $id ): bool
SSE_Lists::get_subscriber_count( int $id ): int

SSE_Subscribers

SSE_Subscribers::create( array $data ): int|WP_Error
SSE_Subscribers::get( int $id ): object|null
SSE_Subscribers::get_by_email( string $email ): object|null
SSE_Subscribers::get_by_cookie( string $cookie_id ): object|null
SSE_Subscribers::get_by_user_id( int $user_id ): object|null
SSE_Subscribers::update( int $id, array $data ): bool
SSE_Subscribers::delete( int $id ): bool
SSE_Subscribers::get_all( array $args ): array
SSE_Subscribers::count( array $args ): int
SSE_Subscribers::subscribe_to_list( int $subscriber_id, int $list_id, string $status = 'subscribed' ): bool
SSE_Subscribers::unsubscribe_from_list( int $subscriber_id, int $list_id ): bool
SSE_Subscribers::get_lists( int $subscriber_id ): array
SSE_Subscribers::export_csv( array $args ): void  // Streams CSV
SSE_Subscribers::total_count(): int

SSE_Forms

SSE_Forms::create( array $data ): int|WP_Error
SSE_Forms::get( int $id ): object|null  // JSON fields auto-decoded
SSE_Forms::get_all( array $args ): array
SSE_Forms::count( array $args ): int
SSE_Forms::update( int $id, array $data ): bool
SSE_Forms::delete( int $id ): bool
SSE_Forms::render( int $id, string $context = 'inline' ): string
SSE_Forms::get_popups_for_page( int $page_id, string $url ): array

Phase 2 — sending pipeline

sse_send() (global function)

The public send API. Used by ssp-product-renewals and any other plugin that wants SSE to deliver one message.

sse_send( array $args ): int|WP_Error

$args keys:

Key	Type	Description
email (or subscriber_email)	string	Recipient email (required)
category	string	One of: newsletter / list_broadcast / product_marketing / product_support / onboarding / transactional. Default: transactional.
subject	string	Subject line (required)
body_text	string	Plain-text body (required)
body_html	string	Optional HTML body
from_name / from_email / reply_to	string	Optional per-message overrides
subscriber_id	int	Optional; resolves automatically from email if omitted
campaign_id / automation_id	int	Optional FKs for log row
gate_context	array	Per-call hints for the suppression gate (e.g. { category_term_id: 12 } for newsletter sends)
context	array	Snapshot data persisted to sse_email_log.context
source_plugin / source_reference	string	For third-party integrations
priority	int	Queue priority (lower = sooner). Default 10 for marketing, 1 for transactional.

Returns: the new sse_email_log row ID, or WP_Error (invalid email, blocked by suppression gate, queue insert failure).

A return of WP_Error( 'sse_suppressed', ... ) is normal — it means the recipient is suppressed for that category and the send was correctly skipped.

SSE_Suppressions

SSE_Suppressions::add( string $email, string $scope = 'global', string $reason = '', string $source = '' ): int|false
SSE_Suppressions::remove( string $email, string $scope = 'global' ): bool
SSE_Suppressions::is_suppressed( string $email, string $scope ): bool
SSE_Suppressions::is_globally_suppressed( string $email ): bool
SSE_Suppressions::get_scopes_for_email( string $email ): string[]
SSE_Suppressions::get_all( array $args ): array
SSE_Suppressions::count( array $args ): int

Constants: REASON_USER_UNSUBSCRIBE, REASON_COMPLAINT, REASON_BOUNCE_HARD, REASON_BOUNCE_SOFT_REPEAT, REASON_MANUAL, REASON_MIGRATED.

SSE_Suppression_Gate

SSE_Suppression_Gate::check( string $email, string $category, array $context = array() ): array
// Returns: [ 'allowed' => bool, 'reason' => string|null ]

Encapsulates the category × suppression matrix. Every send goes through this.

SSE_Email_Log

SSE_Email_Log::create( array $data ): int  // Always reads test_mode from option
SSE_Email_Log::get( int $id ): object|null
SSE_Email_Log::record_event( int $log_id, string $event, string|null $occurred_at = null ): bool
SSE_Email_Log::find_by_mailgun_id( string $message_id ): object|null
SSE_Email_Log::for_subscriber( int $subscriber_id, array $args = array() ): array
SSE_Email_Log::campaign_stats( int $campaign_id ): array

SSE_Email_Queue

SSE_Email_Queue::init(): void  // Registers cron schedule + drain hook
SSE_Email_Queue::enqueue( int $log_id, int $priority = 10 ): int|false
SSE_Email_Queue::drain( int|null $batch_size = null ): int  // Returns messages sent
SSE_Email_Queue::pending_count(): int

SSE_Sender

SSE_Sender::send( array $args ): bool|WP_Error
// Internal — wraps wp_mail with category-aware From + Mailgun header injection.
// You don't call this directly; sse_send() / the drainer do.

SSE_Campaigns

SSE_Campaigns::create( array $data ): int|WP_Error
SSE_Campaigns::get( int $id ): object|null
SSE_Campaigns::get_all( array $args ): array
SSE_Campaigns::update( int $id, array $data ): bool|WP_Error
SSE_Campaigns::delete( int $id ): bool
SSE_Campaigns::send( int $id ): array|WP_Error  // Refuses unless status in draft/scheduled
SSE_Campaigns::send_test( int $id, string $to_email ): int|WP_Error
SSE_Campaigns::reset_to_draft( int $id ): bool
SSE_Campaigns::resolve_audience( object $campaign ): int[]  // Subscriber IDs

Status constants: STATUS_DRAFT, STATUS_SCHEDULED, STATUS_SENDING, STATUS_SENT, STATUS_CANCELLED.

SSE_Confirmations

SSE_Confirmations::issue( int $subscriber_id, int[] $list_ids, int|null $form_id = null ): string  // Token
SSE_Confirmations::consume( string $token ): object|WP_Error  // Returns the subscriber row
SSE_Confirmations::send_confirmation_email( int $subscriber_id, string $token ): int|WP_Error

SSE_Newsletter

SSE_Newsletter::init(): void  // Registers transition_post_status + hourly tick
SSE_Newsletter::enabled_terms(): int[]  // Allowed top-level term_ids
SSE_Newsletter::dispatch_instant( int $post_id ): int  // Recipients queued
SSE_Newsletter::run_digest( int|null $now_gmt = null ): int  // Recipients queued
SSE_Newsletter::resolve_top_level_terms( int $post_id ): int[]
SSE_Newsletter::is_schedule_match( int $now_gmt = null ): bool

SSE_Bundles

SSE_Bundles::components_of( int $product_id ): int[]  // [] if not a bundle
SSE_Bundles::is_available(): bool  // True if WC Product Bundles tables present

SSE_Product_Owners

SSE_Product_Owners::init(): void  // Registers WC hooks
SSE_Product_Owners::on_status_changed( int $order_id, string $old, string $new, $order = null ): void
SSE_Product_Owners::rebuild_for_order( int $order_id ): void
SSE_Product_Owners::rebuild_all( int $days = 0 ): int  // Backfill (used by migration)
SSE_Product_Owners::subscriber_ids_owning( int $product_id, bool $include_bundles = true ): int[]

Constant: PAID_STATUSES = [ 'completed', 'processing' ].

SSE_Segment

SSE_Segment::resolve( array $query, string $category = 'list_broadcast' ): int[]  // Wraps with suppression mask
SSE_Segment::resolve_raw( array $query ): int[]  // No mask — for testing

See Product Audiences & Segments for the predicate language.

SSE_Automations

SSE_Automations::create( array $data ): int|WP_Error
SSE_Automations::get( int $id ): object|null  // trigger_config auto-decoded
SSE_Automations::get_all( array $args = array() ): array
SSE_Automations::update( int $id, array $data ): bool
SSE_Automations::delete( int $id ): bool
SSE_Automations::add_step( int $automation_id, array $data ): int
SSE_Automations::update_step( int $step_id, array $data ): bool
SSE_Automations::delete_step( int $step_id ): bool
SSE_Automations::get_steps( int $automation_id ): array
SSE_Automations::count_steps( int $automation_id ): int

SSE_Automation_Scheduler

SSE_Automation_Scheduler::init(): void  // Registers WC hooks + tick
SSE_Automation_Scheduler::enroll( int $automation_id, int $subscriber_id, array $context = [] ): int|WP_Error  // Idempotent on (auto, sub, context_hash)
SSE_Automation_Scheduler::tick(): int  // Number of steps fired
SSE_Automation_Scheduler::on_wc_order_status_changed( int $order_id, string $old, string $new, $order = null ): void
SSE_Automation_Scheduler::on_wc_order_refunded( int $order_id ): void
SSE_Automation_Scheduler::match_wc_product_purchased( object $automation, array $purchase_data ): bool
SSE_Automation_Scheduler::registered_triggers(): array  // Filterable via 'sse_automation_triggers'

SSE_Mailgun_Webhook

SSE_Mailgun_Webhook::handle( WP_REST_Request $request ): WP_REST_Response
// Registered at /wp-json/sse/v1/mailgun-webhook. HMAC-verified.

SSE_Migrate (Phase 2F)

SSE_Migrate::apply_subscriber( array $rec, bool $commit = false ): array
SSE_Migrate::import_wc_customers( int $days = 0, bool $commit = false ): array

Action constants: ACTION_ACTIVE, ACTION_PENDING, ACTION_UNSUBSCRIBED, ACTION_BOUNCED, ACTION_COMPLAINED.

SSE_Migrate_MailPoet::is_installed(): bool
SSE_Migrate_MailPoet::build_list_map( bool $commit = false, array $existing_map = [] ): array
SSE_Migrate_MailPoet::run( bool $commit = false ): array  // Report

SSE_Migrate_MailerLite::parse_csv( string $path ): array
SSE_Migrate_MailerLite::run( string $path, bool $commit = false ): array  // Report

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Filters & Actions

apply_filters( 'sse_automation_triggers', array $triggers ): array

Register custom triggers for SSE automations. Used by ssp-product-renewals (and anyone else).

add_filter( 'sse_automation_triggers', function( $triggers ) {
    $triggers['renewal_due_t30'] = array(
        'label'   => 'Renewal due in 30 days',
        'matcher' => 'my_plugin_match_renewal_t30',  // callable
    );
    return $triggers;
} );

Your matcher is called by the scheduler when external code invokes SSE_Automation_Scheduler::enroll() for that trigger type. See class-sse-automation-scheduler.php for the calling convention.

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AJAX Endpoints

sse_subscribe

Form submissions. Registered for both logged-in and anonymous users.

POST: sse_form_id, sse_email, sse_first_name, sse_last_name, sse_nonce, sse_hp (honeypot)

Response: { success, data }

sse_update_subscriptions

Subscription preference updates from the management page. Also handles newsletter category prefs + frequency.

POST: nonce, list_ids[], newsletter_terms[], digest_frequency

Response: { success, data: { message } }

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REST API

GET /wp-json/sse/v1/forms

Returns active forms. Used by the Gutenberg block editor.

Permission: edit_posts Response: [ { id, name }, ... ]

GET /wp-json/sse/v1/confirm?token=...

Double opt-in confirmation landing. Consumes the token, flips subscriber to active.

Permission: public

POST /wp-json/sse/v1/mailgun-webhook

MailGun event ingestion endpoint. HMAC-verified using sse_mailgun_webhook_key.

Permission: public (signature is the security)

---

WP-CLI Commands

wp sse migrate mailpoet     [--dry-run|--commit]
wp sse migrate mailerlite   --file=<path>  [--dry-run|--commit]
wp sse migrate wc-customers [--days=<n>]   [--dry-run|--commit]
wp sse migrate report

Default mode is --dry-run. --commit writes. Re-runs are idempotent.

See Email Migration Guide for usage.

---

Cron Schedules

Registered by SSE_Activator::schedule_cron() on activation:

Hook	Interval	Class
sse_drain_email_queue	every minute (sse_every_minute)	SSE_Email_Queue::drain()
sse_newsletter_digest_tick	hourly	SSE_Newsletter::run_digest_if_due()
sse_automation_tick	every minute	SSE_Automation_Scheduler::tick()

Custom interval sse_every_minute is added via the cron_schedules filter in SSE_Email_Queue::init().

---

Constants

Defined in super-speedy-emails.php:

Constant	Value
SSE_VERSION	1.04 (read from plugin header)
SSE_PLUGIN_DIR	Absolute path to plugin directory
SSE_PLUGIN_URL	URL to plugin directory
SSE_PLUGIN_FILE	Path to main plugin file
SSE_PLUGIN_BASENAME	Plugin basename for hooks

---

Options

Phase 1

Option	Default	Description
sse_db_version	2.5.0	Database schema version
sse_from_name	Site name	Global sender name
sse_from_email	Admin email	Global sender email
sse_manage_page_id	0	ID of the subscription management page
sse_wc_myaccount_enabled	false	WooCommerce My Account tab toggle
sse_wc_endpoint_slug	email-preferences	WooCommerce endpoint slug
sse_cookie_lifetime	365	Cookie lifetime (days)
sse_delete_data_on_uninstall	false	Delete all data on uninstall

Phase 2 — sending

Option	Default	Description
sse_test_mode	live	live / log_only / redirect
sse_test_redirect_email	empty	Destination for redirect mode
sse_mailgun_webhook_key	empty	MailGun webhook signing key
sse_from_name__<category>	empty	Per-category sender name override
sse_from_email__<category>	empty	Per-category sender email override
sse_reply_to__<category>	empty	Per-category Reply-To override
sse_newsletter_enabled_terms	[]	JSON array of term_ids enabled for the newsletter
sse_newsletter_schedule	[{day:tue,hour:12},{day:sat,hour:12}]	Digest schedule (GMT)
sse_newsletter_digest_intro	empty	Optional intro text above the post list
sse_newsletter_last_run_at	0	Unix timestamp of last digest run
sse_migrate_mailpoet_prefix	empty	Override MailPoet table prefix (testing)
sse_support_email_cron_enabled	0	Opt-in: run every active Support Email on the daily sse_support_email_check cron

---

Support Emails (product-update / changelog engine)

Added in DB 2.3.0. A Support Email is a record in sse_support_rules; the engine fans out over its product checklist (one email per product to that product’s owners), applying a per-day guard, the suppression gate and recency rules. Full guide: Automated Support Emails — Developer Guide.

Table sse_support_rules: id, name, status (draft/active/paused), product_ids (JSON — the fan-out checklist), match_mode (all/any), conditions (JSON recency rules), subject, body, last_run_at, created_at, updated_at. (reference_mode/freq_cap_days columns are legacy/unused.)

Classes:

• SSE_Support_Rules — CRUD for the records + passes_audience($record,$context) (recency rules) + describe().
• SSE_Support_Emails — the engine: plan_support_email($record,$is_preview,$only_product), run_support_email($record,$only_product), daily_check() (cron, opt-in), AJAX ajax_preview() / ajax_send().
• SSE_Support_Context — the object passed to every support-email hook (support_email_id, product_id, subscriber, matching_product, matching_products[], all_products[], is_preview, name; helpers is_product_mode(), owns(), bought_within(), owned_row(), wc_customer()).

Hooks (each callback gets ($value, SSE_Support_Context $context)):

• sse_should_send_support_email (filter, per product, default true)
• sse_support_email_subject (filter, optional subject override)
• sse_support_email_content (filter, returns { body, name })
• sse_support_email_should_send_to_user (filter, per owner, default true)
• sse_support_email_sent (action, per queued email, real sends only)

There is no sse_support_email_product_ids filter and no version/reference dedup — repeat behaviour is the per-day guard (sse_email_log.source_reference = support:<record_id>:<product_id>). Changelog behaviour lives in the separate ssp-changelog-emails companion plugin.

AJAX actions: sse_support_email_preview (per-product preview from the unsaved editor form), sse_support_email_send (send one product of a saved record).

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CSS Classes

Frontend form classes for custom styling — unchanged from Phase 1.

Class	Element
.sse-form	Form wrapper
.sse-form--minimal / --clean / --branded	Preset modifier
.sse-form--loading	Applied during AJAX submission
.sse-form--success	Applied after successful submission
.sse-form__inner	The <form> element
.sse-form__fields	Fields container (flexbox)
.sse-form__field	Individual field wrapper
.sse-form__input	Input elements
.sse-form__input.sse-has-error	Input with validation error
.sse-form__submit	Submit button
.sse-form__message	Error/info message area
.sse-form__success	Success message (hidden until success)
[data-form-id="X"]	Target a specific form by ID

---

Enqueued Assets

Handle	Type	When loaded
sse-forms	CSS + JS	When a form is rendered
sse-popup	CSS + JS	When a popup form matches the current page
sse-admin	CSS + JS	Admin pages with sse- in the hook

---

Extending: a worked example

A third-party plugin (e.g. ssp-product-renewals) that wants to send a renewal email through SSE:

// In your plugin:
$result = sse_send( array(
    'email'            => $customer_email,
    'category'         => 'product_marketing',
    'subject'          => 'Your Scalability Pro renewal is due',
    'body_text'        => $rendered_body,
    'subscriber_id'    => $sub_id,
    'context'          => array(
        'order_id'       => $order_id,
        'product_id'     => $product_id,
        'renewal_due_at' => $due_at,
    ),
    'source_plugin'    => 'ssp-product-renewals',
    'source_reference' => "renewal:order:{$order_id}:t-{$days_until}",
) );

if ( is_wp_error( $result ) ) {
    if ( $result->get_error_code() === 'sse_suppressed' ) {
        // Recipient is suppressed for this category — that's a normal outcome.
        // Log it for your own audit if needed, but don't treat as a failure.
    } else {
        // Genuine error — invalid email, DB failure, etc.
        error_log( 'SSE send failed: ' . $result->get_error_message() );
    }
}
// $result is the sse_email_log row ID on success.

SSE handles the gate check, queue insert, From: address per category, audit logging, and delivery via the cron drainer. The other plugin doesn’t need to know about MailGun, suppressions, or queues — just compose and call.