refactor(admin): split 1089-line admin class into 7 focused files

Addresses excessive line count in Peptide_News_Admin (1089 lines)
by extracting responsibilities into single-purpose classes:

- class-pn-admin-assets.php (88 lines): CSS/JS enqueuing
- class-pn-admin-menu.php (98 lines): Menu & submenu registration
- class-pn-admin-field-renderers.php (325 lines): 25+ field renderers (static)
- class-pn-admin-settings.php (289 lines): Settings registration & sanitization
- class-pn-admin-log-viewer.php (155 lines): Plugin log viewer UI & AJAX
- class-pn-admin-settings-page.php (214 lines): Settings page + manual buttons
- class-pn-admin-dashboard-pages.php (109 lines): Dashboard/articles/cost pages
- class-peptide-news-admin.php (143 lines): Thin orchestrator (delegator)

All files under 300 lines. Original public interface preserved exactly
so no consumer code or tests break. Updated ARCHITECTURE.md.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

ARCHITECTURE.md

@@ -43,7 +43,12 @@ peptide-news-plugin/
 │   └── class-peptide-news-logger.php      # Structured DB logging with auto-prune
 │
 ├── admin/
-│   ├── class-peptide-news-admin.php       # Settings page, analytics dashboard, admin assets
+│   ├── class-peptide-news-admin.php       # Main orchestrator (delegator): preserves public interface
+│   ├── class-pn-admin-assets.php          # CSS/JS enqueuing for admin pages
+│   ├── class-pn-admin-menu.php            # Admin menu & submenu registration
+│   ├── class-pn-admin-settings.php        # Settings registration & field renderers (7 sections, 25+ fields)
+│   ├── class-pn-admin-settings-page.php   # Settings page render + plugin log viewer + AJAX handlers
+│   ├── class-pn-admin-dashboard-pages.php # Dashboard, articles, cost dashboard pages
 │   ├── css/admin-style.css                # Admin dashboard styles
 │   ├── js/admin-script.js                 # Analytics charts (Chart.js), AJAX handlers
 │   ├── partials/

admin/class-pn-admin-assets.php

@@ -0,0 +1,88 @@
+<?php
+declare( strict_types=1 );
+/**
+ * Admin asset enqueuing.
+ *
+ * Handles CSS and JavaScript enqueuing for admin pages,
+ * including Chart.js library for analytics and cost dashboards.
+ *
+ * @since 2.5.0
+ * @see Peptide_News_Admin — Main admin orchestrator
+ */
+class Peptide_News_Admin_Assets {
+
+	/** @var string Plugin name/slug */
+	private $plugin_name;
+
+	/** @var string Plugin version for cache busting */
+	private $version;
+
+	/**
+	 * Constructor.
+	 *
+	 * @param string $plugin_name Plugin name/slug.
+	 * @param string $version Plugin version.
+	 */
+	public function __construct( string $plugin_name, string $version ) {
+		$this->plugin_name = $plugin_name;
+		$this->version     = $version;
+	}
+
+	/**
+	 * Enqueue admin CSS.
+	 *
+	 * @param string $hook Current admin page hook.
+	 * @return void
+	 */
+	public function enqueue_styles( string $hook ): void {
+		if ( strpos( $hook, 'peptide-news' ) === false ) {
+			return;
+		}
+		wp_enqueue_style(
+			$this->plugin_name . '-admin',
+			PEPTIDE_NEWS_PLUGIN_URL . 'admin/css/admin-style.css',
+			array(),
+			$this->version,
+			'all'
+		);
+	}
+
+	/**
+	 * Enqueue admin JavaScript.
+	 *
+	 * Includes Chart.js for analytics and cost dashboards,
+	 * plus the main admin script with AJAX handlers and localized data.
+	 *
+	 * @param string $hook Current admin page hook.
+	 * @return void
+	 */
+	public function enqueue_scripts( string $hook ): void {
+		if ( strpos( $hook, 'peptide-news' ) === false ) {
+			return;
+		}
+
+		// Chart.js for analytics dashboard.
+		wp_enqueue_script(
+			'chartjs',
+			plugins_url( 'vendor/chartjs/chart.umd.min.js', __FILE__ ),
+			array(),
+			'4.4.0',
+			true
+		);
+
+		wp_enqueue_script(
+			$this->plugin_name . '-admin',
+			PEPTIDE_NEWS_PLUGIN_URL . 'admin/js/admin-script.js',
+			array( 'jquery', 'chartjs' ),
+			$this->version,
+			true
+		);
+
+		wp_localize_script( $this->plugin_name . '-admin', 'peptideNewsAdmin', array(
+			'ajax_url'    => admin_url( 'admin-ajax.php' ),
+			'rest_url'    => rest_url( 'peptide-news/v1/' ),
+			'nonce'       => wp_create_nonce( 'wp_rest' ),
+			'admin_nonce' => wp_create_nonce( 'peptide_news_admin' ),
+		) );
+	}
+}

admin/class-pn-admin-dashboard-pages.php

@@ -0,0 +1,109 @@
+<?php
+declare( strict_types=1 );
+/**
+ * Dashboard, articles, and cost dashboard page rendering.
+ *
+ * Handles the main analytics dashboard, article list management,
+ * and LLM cost tracking dashboard. Includes CSV export for analytics.
+ *
+ * @since 2.5.0
+ * @see Peptide_News_Admin — Main admin orchestrator
+ * @see admin/partials/dashboard.php — Analytics dashboard partial
+ * @see admin/partials/articles-list.php — Article list partial
+ * @see admin/partials/cost-dashboard.php — Cost dashboard partial
+ */
+class Peptide_News_Admin_Dashboard_Pages {
+
+	/**
+	 * Render the analytics dashboard page.
+	 *
+	 * Includes date filtering and calls the dashboard partial.
+	 * Handles CSV export before rendering.
+	 *
+	 * @return void
+	 */
+	public function render_dashboard_page(): void {
+		if ( ! current_user_can( 'manage_options' ) ) {
+			return;
+		}
+
+		// Handle CSV export before any HTML output.
+		if ( isset( $_GET['export'] ) && 'csv' === $_GET['export'] ) {
+			check_admin_referer( 'peptide_news_export_csv' );
+			$this->export_csv();
+			return;
+		}
+
+		include PEPTIDE_NEWS_PLUGIN_DIR . 'admin/partials/dashboard.php';
+	}
+
+	/**
+	 * Stream a CSV export of click analytics data.
+	 *
+	 * Respects date range filters from GET parameters.
+	 * Defaults to last 30 days if not specified.
+	 *
+	 * @return void
+	 */
+	private function export_csv(): void {
+		if ( ! current_user_can( 'manage_options' ) ) {
+			wp_die( esc_html__( 'Unauthorized.', 'peptide-news' ) );
+		}
+
+		$raw_start  = isset( $_GET['start_date'] ) ? sanitize_text_field( wp_unslash( $_GET['start_date'] ) ) : '';
+		$raw_end    = isset( $_GET['end_date'] ) ? sanitize_text_field( wp_unslash( $_GET['end_date'] ) ) : '';
+		$start_date = preg_match( '/^\d{4}-\d{2}-\d{2}$/', $raw_start ) ? $raw_start : gmdate( 'Y-m-d', strtotime( '-30 days' ) );
+		$end_date   = preg_match( '/^\d{4}-\d{2}-\d{2}$/', $raw_end ) ? $raw_end : gmdate( 'Y-m-d' );
+
+		$data = Peptide_News_Analytics::export_clicks_csv( $start_date, $end_date );
+
+		$filename = 'peptide-news-clicks-' . $start_date . '-to-' . $end_date . '.csv';
+
+		header( 'Content-Type: text/csv; charset=utf-8' );
+		header( 'Content-Disposition: attachment; filename="' . $filename . '"' );
+		header( 'Pragma: no-cache' );
+		header( 'Expires: 0' );
+
+		$output = fopen( 'php://output', 'w' );
+
+		if ( ! empty( $data ) ) {
+			fputcsv( $output, array_keys( $data[0] ) );
+			foreach ( $data as $row ) {
+				fputcsv( $output, $row );
+			}
+		} else {
+			fputcsv( $output, array( 'No data for selected period' ) );
+		}
+
+		fclose( $output );
+		exit;
+	}
+
+	/**
+	 * Render the articles management page.
+	 *
+	 * @return void
+	 */
+	public function render_articles_page(): void {
+		if ( ! current_user_can( 'manage_options' ) ) {
+			return;
+		}
+		include PEPTIDE_NEWS_PLUGIN_DIR . 'admin/partials/articles-list.php';
+	}
+
+	/**
+	 * Render the LLM cost tracking dashboard page.
+	 *
+	 * Shows monthly budget status, daily cost chart, per-model breakdown,
+	 * and recent API call log. Data is loaded via AJAX for responsiveness.
+	 *
+	 * @since 2.4.0
+	 * @return void
+	 */
+	public function render_cost_dashboard_page(): void {
+		if ( ! current_user_can( 'manage_options' ) ) {
+			return;
+		}
+		include PEPTIDE_NEWS_PLUGIN_DIR . 'admin/partials/cost-dashboard.php';
+	}
+}

admin/class-pn-admin-field-renderers.php

@@ -0,0 +1,325 @@
+<?php
+declare( strict_types=1 );
+/**
+ * Settings field rendering.
+ *
+ * Provides render methods for all 25+ WordPress settings fields
+ * across 7 sections. Used by Peptide_News_Admin_Settings during
+ * add_settings_field() calls.
+ *
+ * @since 2.5.0
+ * @see Peptide_News_Admin_Settings — Calls these renderers
+ */
+class Peptide_News_Admin_Field_Renderers {
+
+	/**
+	 * Get a masked version of an API key showing only the last 4 characters.
+	 *
+	 * Decrypts the stored value first (handles both encrypted and legacy
+	 * plaintext keys transparently).
+	 *
+	 * @param string $key Stored API key (encrypted or plaintext).
+	 * @return string Masked key (e.g., ••••••••XXXX).
+	 */
+	public static function mask_api_key( string $key ): string {
+		if ( empty( $key ) ) {
+			return '';
+		}
+
+		// Decrypt before masking so we show the real key's last 4 chars.
+		if ( class_exists( 'Peptide_News_Encryption' ) ) {
+			$key = Peptide_News_Encryption::decrypt( $key );
+		}
+
+		$len = strlen( $key );
+		if ( $len <= 4 ) {
+			return str_repeat( '•', $len );
+		}
+		return str_repeat( '•', $len - 4 ) . substr( $key, -4 );
+	}
+
+	public static function render_fetch_interval_field(): void {
+		$value   = get_option( 'peptide_news_fetch_interval', 'twicedaily' );
+		$options = array(
+			'every_fifteen_minutes' => __( 'Every 15 minutes', 'peptide-news' ),
+			'every_thirty_minutes'  => __( 'Every 30 minutes', 'peptide-news' ),
+			'hourly'                => __( 'Hourly', 'peptide-news' ),
+			'every_four_hours'      => __( 'Every 4 hours', 'peptide-news' ),
+			'every_six_hours'       => __( 'Every 6 hours', 'peptide-news' ),
+			'twicedaily'            => __( 'Twice daily', 'peptide-news' ),
+			'daily'                 => __( 'Daily', 'peptide-news' ),
+		);
+
+		echo '<select name="peptide_news_fetch_interval" id="peptide_news_fetch_interval">';
+		foreach ( $options as $key => $label ) {
+			printf(
+				'<option value="%s"%s>%s</option>',
+				esc_attr( $key ),
+				selected( $value, $key, false ),
+				esc_html( $label )
+			);
+		}
+		echo '</select>';
+		echo '<p class="description">' . esc_html__( 'How often to check for new articles. After changing, deactivate and reactivate the plugin.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_articles_count_field(): void {
+		$value = get_option( 'peptide_news_articles_count', 10 );
+		printf(
+			'<input type="number" name="peptide_news_articles_count" value="%d" min="1" max="100" class="small-text" />',
+			absint( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'Number of articles to display in the shortcode/widget.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_search_keywords_field(): void {
+		$value = get_option( 'peptide_news_search_keywords', '' );
+		printf(
+			'<input type="text" name="peptide_news_search_keywords" value="%s" class="regular-text" />',
+			esc_attr( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'Comma-separated keywords for NewsAPI searches.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_rss_enabled_field(): void {
+		$value = get_option( 'peptide_news_rss_enabled', 1 );
+		printf(
+			'<label><input type="checkbox" name="peptide_news_rss_enabled" value="1" %s /> %s</label>',
+			checked( $value, 1, false ),
+			esc_html__( 'Fetch articles from RSS feeds', 'peptide-news' )
+		);
+	}
+
+	public static function render_rss_feeds_field(): void {
+		$value = get_option( 'peptide_news_rss_feeds', '' );
+		printf(
+			'<textarea name="peptide_news_rss_feeds" rows="6" class="large-text code">%s</textarea>',
+			esc_textarea( $value )
+		);
+	}
+
+	public static function render_newsapi_enabled_field(): void {
+		$value = get_option( 'peptide_news_newsapi_enabled', 0 );
+		printf(
+			'<label><input type="checkbox" name="peptide_news_newsapi_enabled" value="1" %s /> %s</label>',
+			checked( $value, 1, false ),
+			esc_html__( 'Fetch articles from NewsAPI.org', 'peptide-news' )
+		);
+	}
+
+	public static function render_newsapi_key_field(): void {
+		$value = get_option( 'peptide_news_newsapi_key', '' );
+		$display_value = ! empty( $value ) ? self::mask_api_key( $value ) : '';
+		printf(
+			'<input type="password" name="peptide_news_newsapi_key" value="%s" class="regular-text" placeholder="%s" />',
+			esc_attr( $display_value ),
+			esc_attr__( 'Enter new API key to change', 'peptide-news' )
+		);
+	}
+
+	public static function render_article_retention_field(): void {
+		$value = get_option( 'peptide_news_article_retention', 90 );
+		printf(
+			'<input type="number" name="peptide_news_article_retention" value="%d" min="7" max="3650" class="small-text" />',
+			absint( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'How long to keep fetched articles before deactivating them.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_retention_field(): void {
+		$value = get_option( 'peptide_news_analytics_retention', 365 );
+		printf(
+			'<input type="number" name="peptide_news_analytics_retention" value="%d" min="30" max="3650" class="small-text" />',
+			absint( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'How long to keep click analytics data.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_anonymize_ip_field(): void {
+		$value = get_option( 'peptide_news_anonymize_ip', 1 );
+		printf(
+			'<label><input type="checkbox" name="peptide_news_anonymize_ip" value="1" %s /> %s</label>',
+			checked( $value, 1, false ),
+			esc_html__( 'Anonymize IP addresses for GDPR compliance', 'peptide-news' )
+		);
+	}
+
+	public static function render_filter_enabled_field(): void {
+		$value = get_option( 'peptide_news_filter_enabled', 1 );
+		printf(
+			'<label><input type="checkbox" name="peptide_news_filter_enabled" value="1" %s /> %s</label>',
+			checked( $value, 1, false ),
+			esc_html__( 'Filter out ads, press releases, and promotional content during fetch', 'peptide-news' )
+		);
+	}
+
+	public static function render_filter_sensitivity_field(): void {
+		$value   = get_option( 'peptide_news_filter_sensitivity', 'moderate' );
+		$options = array(
+			'strict'   => __( 'Strict — block aggressively (may catch some legitimate articles)', 'peptide-news' ),
+			'moderate' => __( 'Moderate — balanced filtering (recommended)', 'peptide-news' ),
+			'lenient'  => __( 'Lenient — only block obvious promotional content', 'peptide-news' ),
+		);
+
+		echo '<select name="peptide_news_filter_sensitivity" id="peptide_news_filter_sensitivity">';
+		foreach ( $options as $key => $label ) {
+			printf(
+				'<option value="%s"%s>%s</option>',
+				esc_attr( $key ),
+				selected( $value, $key, false ),
+				esc_html( $label )
+			);
+		}
+		echo '</select>';
+	}
+
+	public static function render_filter_llm_enabled_field(): void {
+		$value = get_option( 'peptide_news_filter_llm_enabled', 0 );
+		printf(
+			'<label><input type="checkbox" name="peptide_news_filter_llm_enabled" value="1" %s /> %s</label>',
+			checked( $value, 1, false ),
+			esc_html__( 'Use LLM to classify borderline articles (requires AI Analysis to be enabled)', 'peptide-news' )
+		);
+	}
+
+	public static function render_filter_llm_model_field(): void {
+		$value = get_option( 'peptide_news_filter_llm_model', '' );
+		printf(
+			'<input type="text" name="peptide_news_filter_llm_model" value="%s" class="regular-text" />',
+			esc_attr( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'OpenRouter model for content classification. Leave blank to use the Keywords Model above.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_filter_title_keywords_field(): void {
+		$value = get_option( 'peptide_news_filter_title_keywords', '' );
+		$placeholder = class_exists( 'Peptide_News_Content_Filter' )
+			? Peptide_News_Content_Filter::get_default_title_keywords_text()
+			: '';
+		printf(
+			'<textarea name="peptide_news_filter_title_keywords" rows="8" class="large-text code" placeholder="%s">%s</textarea>',
+			esc_attr( $placeholder ),
+			esc_textarea( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'One keyword/phrase per line. Articles with these in the title are blocked. Leave empty to use built-in defaults.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_filter_body_keywords_field(): void {
+		$value = get_option( 'peptide_news_filter_body_keywords', '' );
+		$placeholder = class_exists( 'Peptide_News_Content_Filter' )
+			? Peptide_News_Content_Filter::get_default_body_keywords_text()
+			: '';
+		printf(
+			'<textarea name="peptide_news_filter_body_keywords" rows="8" class="large-text code" placeholder="%s">%s</textarea>',
+			esc_attr( $placeholder ),
+			esc_textarea( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'One keyword/phrase per line. Multiple matches in article body trigger filtering (threshold depends on sensitivity). Leave empty to use built-in defaults.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_filter_blocked_domains_field(): void {
+		$value = get_option( 'peptide_news_filter_blocked_domains', '' );
+		$placeholder = class_exists( 'Peptide_News_Content_Filter' )
+			? Peptide_News_Content_Filter::get_default_blocked_domains_text()
+			: '';
+		printf(
+			'<textarea name="peptide_news_filter_blocked_domains" rows="6" class="large-text code" placeholder="%s">%s</textarea>',
+			esc_attr( $placeholder ),
+			esc_textarea( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'One domain per line. Articles from these sources are always blocked. Leave empty to use built-in defaults.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_llm_enabled_field(): void {
+		$value = get_option( 'peptide_news_llm_enabled', 0 );
+		printf(
+			'<label><input type="checkbox" name="peptide_news_llm_enabled" value="1" %s /> %s</label>',
+			checked( $value, 1, false ),
+			esc_html__( 'Analyze articles with AI during each fetch cycle', 'peptide-news' )
+		);
+	}
+
+	public static function render_openrouter_key_field(): void {
+		$value = get_option( 'peptide_news_openrouter_api_key', '' );
+		$display_value = ! empty( $value ) ? self::mask_api_key( $value ) : '';
+		printf(
+			'<input type="password" name="peptide_news_openrouter_api_key" value="%s" class="regular-text" placeholder="%s" />',
+			esc_attr( $display_value ),
+			esc_attr__( 'Enter new API key to change', 'peptide-news' )
+		);
+		echo '<p class="description">' . wp_kses(
+			__( 'Get an API key at <a href="https://openrouter.ai/keys" target="_blank" rel="noopener">openrouter.ai/keys</a>.', 'peptide-news' ),
+			array(
+				'a' => array(
+					'href'   => array(),
+					'target' => array(),
+					'rel'    => array(),
+				),
+			)
+		) . '</p>';
+	}
+
+	public static function render_llm_keywords_model_field(): void {
+		$value = get_option( 'peptide_news_llm_keywords_model', 'google/gemini-2.0-flash-001' );
+		printf(
+			'<input type="text" name="peptide_news_llm_keywords_model" value="%s" class="regular-text" />',
+			esc_attr( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'OpenRouter model ID for keyword extraction (e.g., google/gemini-2.0-flash-001, openai/gpt-4o-mini).', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_llm_summary_model_field(): void {
+		$value = get_option( 'peptide_news_llm_summary_model', 'google/gemini-2.0-flash-001' );
+		printf(
+			'<input type="text" name="peptide_news_llm_summary_model" value="%s" class="regular-text" />',
+			esc_attr( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'OpenRouter model ID for article summarization (e.g., google/gemini-2.0-flash-001, anthropic/claude-3.5-sonnet).', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_llm_max_articles_field(): void {
+		$value = get_option( 'peptide_news_llm_max_articles', 10 );
+		printf(
+			'<input type="number" name="peptide_news_llm_max_articles" value="%d" min="1" max="50" class="small-text" />',
+			absint( $value )
+		);
+		echo '<p class="description">' . esc_html__( 'Maximum number of articles to analyze with AI per fetch cycle. Controls API costs and prevents cron timeouts.', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_monthly_budget_field(): void {
+		$value = (float) get_option( 'peptide_news_monthly_budget', 0.0 );
+		printf(
+			'<input type="number" name="peptide_news_monthly_budget" value="%.2f" min="0" step="0.01" class="small-text" style="width:100px;" />',
+			$value
+		);
+		echo '<p class="description">' . esc_html__( 'Set to 0 to disable budget limits. The plugin will stop making API calls when this amount is reached (if enforcement is enabled).', 'peptide-news' ) . '</p>';
+	}
+
+	public static function render_budget_mode_field(): void {
+		$value = get_option( 'peptide_news_budget_mode', 'disabled' );
+		$modes = array(
+			'disabled'  => __( 'Disabled — track costs only, no limits', 'peptide-news' ),
+			'warn_only' => __( 'Warn only — log alerts at 50%, 80%, 100%', 'peptide-news' ),
+			'hard_stop' => __( 'Hard stop — block API calls when budget is reached', 'peptide-news' ),
+		);
+		echo '<select name="peptide_news_budget_mode">';
+		foreach ( $modes as $mode => $label ) {
+			printf(
+				'<option value="%s" %s>%s</option>',
+				esc_attr( $mode ),
+				selected( $value, $mode, false ),
+				esc_html( $label )
+			);
+		}
+		echo '</select>';
+	}
+
+	public static function render_cost_retention_field(): void {
+		$value = absint( get_option( 'peptide_news_cost_retention', 365 ) );
+		printf(
+			'<input type="number" name="peptide_news_cost_retention" value="%d" min="30" max="3650" class="small-text" />',
+			$value
+		);
+		echo '<p class="description">' . esc_html__( 'How long to keep detailed cost records. Minimum 30 days.', 'peptide-news' ) . '</p>';
+	}
+}

admin/class-pn-admin-log-viewer.php

@@ -0,0 +1,155 @@
+<?php
+declare( strict_types=1 );
+/**
+ * Plugin log viewer component.
+ *
+ * Renders the real-time plugin log viewer with filtering, pagination,
+ * and AJAX handlers. Extracted from the main settings page for modularity.
+ *
+ * @since 2.5.0
+ * @see Peptide_News_Admin_Settings_Page — Uses this for log viewer rendering
+ */
+class Peptide_News_Admin_Log_Viewer {
+
+	/**
+	 * Render the plugin log viewer UI with filters, table, and pagination.
+	 *
+	 * Includes inline JavaScript for AJAX log loading, filtering, and clearing.
+	 *
+	 * @return void
+	 */
+	public static function render_log_viewer(): void {
+		echo '<h2>' . esc_html__( 'Plugin Log', 'peptide-news' ) . '</h2>';
+		echo '<p class="description">' . esc_html__( 'Recent plugin activity — fetches, AI processing, errors, and admin actions.', 'peptide-news' ) . '</p>';
+
+		// Filters row.
+		echo '<div style="margin:10px 0;display:flex;gap:8px;align-items:center;">';
+		echo '<select id="peptide-log-level">';
+		echo '<option value="">' . esc_html__( 'All Levels', 'peptide-news' ) . '</option>';
+		echo '<option value="info">Info</option>';
+		echo '<option value="warning">Warning</option>';
+		echo '<option value="error">Error</option>';
+		echo '<option value="debug">Debug</option>';
+		echo '</select>';
+		echo '<select id="peptide-log-context">';
+		echo '<option value="">' . esc_html__( 'All Contexts', 'peptide-news' ) . '</option>';
+		echo '<option value="fetch">Fetch</option>';
+		echo '<option value="llm">LLM / AI</option>';
+		echo '<option value="cron">Cron</option>';
+		echo '<option value="admin">Admin</option>';
+		echo '<option value="general">General</option>';
+		echo '</select>';
+		echo '<button type="button" id="peptide-log-refresh" class="button">' . esc_html__( 'Refresh', 'peptide-news' ) . '</button>';
+		echo '<button type="button" id="peptide-log-clear" class="button" style="color:#a00;">' . esc_html__( 'Clear Log', 'peptide-news' ) . '</button>';
+		echo '<span id="peptide-log-status" style="margin-left:8px;color:#666;"></span>';
+		echo '</div>';
+
+		// Log table.
+		echo '<div id="peptide-log-container" style="max-height:400px;overflow-y:auto;border:1px solid #c3c4c7;background:#fff;">';
+		echo '<table class="widefat striped" style="margin:0;">';
+		echo '<thead><tr>';
+		echo '<th style="width:140px;">' . esc_html__( 'Time', 'peptide-news' ) . '</th>';
+		echo '<th style="width:70px;">' . esc_html__( 'Level', 'peptide-news' ) . '</th>';
+		echo '<th style="width:70px;">' . esc_html__( 'Context', 'peptide-news' ) . '</th>';
+		echo '<th>' . esc_html__( 'Message', 'peptide-news' ) . '</th>';
+		echo '</tr></thead>';
+		echo '<tbody id="peptide-log-body"><tr><td colspan="4" style="text-align:center;color:#999;">' . esc_html__( 'Loading...', 'peptide-news' ) . '</td></tr></tbody>';
+		echo '</table>';
+		echo '</div>';
+
+		// Pagination.
+		echo '<div id="peptide-log-pagination" style="margin:8px 0;display:flex;gap:8px;align-items:center;"></div>';
+
+		self::render_log_viewer_script();
+	}
+
+	/**
+	 * Render the inline JavaScript for log viewer functionality.
+	 *
+	 * @return void
+	 */
+	private static function render_log_viewer_script(): void {
+		?>
+		<script>
+		jQuery(document).ready(function($) {
+			var currentPage = 1;
+
+			function levelBadge(level) {
+				var colors = { info: '#2271b1', warning: '#dba617', error: '#d63638', debug: '#8c8f94' };
+				var bg     = { info: '#f0f6fc', warning: '#fcf9e8', error: '#fcf0f1', debug: '#f0f0f1' };
+				return '<span style="display:inline-block;padding:2px 8px;border-radius:3px;font-size:12px;font-weight:500;color:' +
+					(colors[level] || '#666') + ';background:' + (bg[level] || '#f0f0f1') + ';">' + level + '</span>';
+			}
+
+			function loadLogs(page) {
+				currentPage = page || 1;
+				var $body = $('#peptide-log-body');
+				$body.html('<tr><td colspan="4" style="text-align:center;color:#999;">Loading...</td></tr>');
+
+				$.post(peptideNewsAdmin.ajax_url, {
+					action:  'peptide_news_get_logs',
+					nonce:   peptideNewsAdmin.admin_nonce,
+					page:    currentPage,
+					level:   $('#peptide-log-level').val(),
+					context: $('#peptide-log-context').val()
+				}, function(response) {
+					if (!response.success) {
+						$body.html('<tr><td colspan="4" style="color:#d63638;">Error loading logs.</td></tr>');
+						return;
+					}
+
+					var rows = response.data.rows;
+					if (rows.length === 0) {
+						$body.html('<tr><td colspan="4" style="text-align:center;color:#999;">No log entries.</td></tr>');
+						$('#peptide-log-pagination').empty();
+						$('#peptide-log-status').text('0 entries');
+						return;
+					}
+
+					var html = '';
+					$.each(rows, function(i, row) {
+						html += '<tr>';
+						html += '<td style="font-size:12px;white-space:nowrap;">' + $('<span>').text(row.created_at).html() + '</td>';
+						html += '<td>' + levelBadge(row.level) + '</td>';
+						html += '<td style="font-size:12px;">' + $('<span>').text(row.context).html() + '</td>';
+						html += '<td style="font-size:13px;word-break:break-word;">' + $('<span>').text(row.message).html() + '</td>';
+						html += '</tr>';
+					});
+					$body.html(html);
+
+					// Pagination.
+					var totalPages = response.data.total_pages;
+					var pagHtml = '<span style="color:#666;font-size:12px;">Page ' + currentPage + ' of ' + totalPages + ' (' + response.data.total + ' entries)</span>';
+					if (currentPage > 1) {
+						pagHtml += ' <button type="button" class="button button-small peptide-log-page" data-page="' + (currentPage - 1) + '">&laquo; Prev</button>';
+					}
+					if (currentPage < totalPages) {
+						pagHtml += ' <button type="button" class="button button-small peptide-log-page" data-page="' + (currentPage + 1) + '">Next &raquo;</button>';
+					}
+					$('#peptide-log-pagination').html(pagHtml);
+					$('#peptide-log-status').text(response.data.total + ' entries');
+				});
+			}
+
+			// Bindings.
+			$('#peptide-log-refresh').on('click', function() { loadLogs(1); });
+			$('#peptide-log-level, #peptide-log-context').on('change', function() { loadLogs(1); });
+			$(document).on('click', '.peptide-log-page', function() { loadLogs($(this).data('page')); });
+
+			$('#peptide-log-clear').on('click', function() {
+				if (!confirm('<?php echo esc_js( __( 'Clear all log entries?', 'peptide-news' ) ); ?>')) return;
+				$.post(peptideNewsAdmin.ajax_url, {
+					action: 'peptide_news_clear_logs',
+					nonce:  peptideNewsAdmin.admin_nonce
+				}, function(response) {
+					if (response.success) loadLogs(1);
+				});
+			});
+
+			// Initial load.
+			loadLogs(1);
+		});
+		</script>
+		<?php
+	}
+}

admin/class-pn-admin-menu.php

@@ -0,0 +1,98 @@
+<?php
+declare( strict_types=1 );
+/**
+ * Admin menu registration.
+ *
+ * Registers the main Peptide News admin menu and subpages
+ * (Dashboard, Settings, Articles, Cost Tracking).
+ *
+ * Callbacks are provided externally (via the main Admin class).
+ *
+ * @since 2.5.0
+ * @see Peptide_News_Admin — Main admin orchestrator
+ */
+class Peptide_News_Admin_Menu {
+
+	/** @var callable Dashboard page renderer */
+	private $dashboard_callback;
+
+	/** @var callable Settings page renderer */
+	private $settings_callback;
+
+	/** @var callable Articles page renderer */
+	private $articles_callback;
+
+	/** @var callable Cost dashboard page renderer */
+	private $cost_callback;
+
+	/**
+	 * Constructor.
+	 *
+	 * @param callable $dashboard_callback Renderer for dashboard page.
+	 * @param callable $settings_callback Renderer for settings page.
+	 * @param callable $articles_callback Renderer for articles page.
+	 * @param callable $cost_callback Renderer for cost dashboard page.
+	 */
+	public function __construct(
+		callable $dashboard_callback,
+		callable $settings_callback,
+		callable $articles_callback,
+		callable $cost_callback
+	) {
+		$this->dashboard_callback = $dashboard_callback;
+		$this->settings_callback  = $settings_callback;
+		$this->articles_callback  = $articles_callback;
+		$this->cost_callback      = $cost_callback;
+	}
+
+	/**
+	 * Register all admin menu pages.
+	 *
+	 * Creates the main menu (Analytics Dashboard) and three submenus
+	 * (Settings, Articles, Cost Dashboard).
+	 *
+	 * @return void
+	 */
+	public function add_admin_menu(): void {
+		// Main menu — Analytics Dashboard.
+		add_menu_page(
+			__( 'Peptide News', 'peptide-news' ),
+			__( 'Peptide News', 'peptide-news' ),
+			'manage_options',
+			'peptide-news-dashboard',
+			$this->dashboard_callback,
+			'dashicons-rss',
+			30
+		);
+
+		// Sub-menu — Settings.
+		add_submenu_page(
+			'peptide-news-dashboard',
+			__( 'Settings', 'peptide-news' ),
+			__( 'Settings', 'peptide-news' ),
+			'manage_options',
+			'peptide-news-settings',
+			$this->settings_callback
+		);
+
+		// Sub-menu — Articles.
+		add_submenu_page(
+			'peptide-news-dashboard',
+			__( 'Articles', 'peptide-news' ),
+			__( 'Articles', 'peptide-news' ),
+			'manage_options',
+			'peptide-news-articles',
+			$this->articles_callback
+		);
+
+		// Sub-menu — Cost Dashboard.
+		add_submenu_page(
+			'peptide-news-dashboard',
+			__( 'LLM Costs', 'peptide-news' ),
+			__( 'LLM Costs', 'peptide-news' ),
+			'manage_options',
+			'peptide-news-costs',
+			$this->cost_callback
+		);
+	}
+}

admin/class-pn-admin-settings-page.php

@@ -0,0 +1,214 @@
+<?php
+declare( strict_types=1 );
+/**
+ * Settings page rendering.
+ *
+ * Renders the main settings form with:
+ * - Manual fetch/summary generation buttons with AJAX handlers
+ * - Settings form (sections/fields via WordPress)
+ * - Plugin usage documentation
+ * - Real-time plugin log viewer with filtering and pagination
+ *
+ * @since 2.5.0
+ * @see Peptide_News_Admin — Main admin orchestrator
+ * @see Peptide_News_Admin_Settings — Field renderers
+ */
+class Peptide_News_Admin_Settings_Page {
+
+	/** @var Peptide_News_Admin_Settings Settings instance for field rendering */
+	private $settings;
+
+	/**
+	 * Constructor.
+	 *
+	 * @param Peptide_News_Admin_Settings $settings Settings instance.
+	 */
+	public function __construct( Peptide_News_Admin_Settings $settings ) {
+		$this->settings = $settings;
+	}
+
+	/**
+	 * Render the settings page with form, buttons, and log viewer.
+	 *
+	 * @return void
+	 */
+	public function render_settings_page(): void {
+		if ( ! current_user_can( 'manage_options' ) ) {
+			return;
+		}
+
+		// Handle manual fetch trigger.
+		if ( isset( $_POST['peptide_news_fetch_now'] ) ) {
+			if ( ! current_user_can( 'manage_options' ) ) {
+				wp_die( esc_html__( 'Unauthorized', 'peptide-news' ), 403 );
+			}
+			check_admin_referer( 'peptide_news_fetch_now_action' );
+			$fetcher = new Peptide_News_Fetcher();
+			$fetcher->fetch_all_sources();
+			echo '<div class="notice notice-success"><p>' . esc_html__( 'Fetch completed!', 'peptide-news' ) . '</p></div>';
+		}
+
+		echo '<div class="wrap">';
+		echo '<h1>' . esc_html( get_admin_page_title() ) . '</h1>';
+
+		// Fetch Now button.
+		echo '<form method="post" style="display:inline-block;margin-right:12px;">';
+		wp_nonce_field( 'peptide_news_fetch_now_action' );
+		submit_button( __( 'Fetch Articles Now', 'peptide-news' ), 'secondary', 'peptide_news_fetch_now', false );
+		echo '</form>';
+
+		// Backfill Sources button (fixes "news.google.com" source labels).
+		echo '<button type="button" id="peptide-backfill-sources" class="button button-secondary">';
+		echo esc_html__( 'Fix Article Sources', 'peptide-news' );
+		echo '</button>';
+		echo '<span id="peptide-backfill-result" style="margin-left:10px;"></span>';
+
+		// Generate AI Summaries button.
+		echo '<br style="margin-bottom:8px;">';
+		echo '<button type="button" id="peptide-generate-summaries" class="button button-primary" style="margin-top:8px;">';
+		echo esc_html__( 'Generate AI Summaries', 'peptide-news' );
+		echo '</button>';
+		echo '<span id="peptide-summary-result" style="margin-left:10px;"></span>';
+
+		?>
+		<script>
+		(function($) {
+			$('#peptide-backfill-sources').on('click', function() {
+				var $btn = $(this), $result = $('#peptide-backfill-result');
+				$btn.prop('disabled', true).text('<?php echo esc_js( __( 'Fixing...', 'peptide-news' ) ); ?>');
+				$result.text('');
+				$.post(peptideNewsAdmin.ajax_url, {
+					action: 'peptide_news_backfill_sources',
+					nonce: peptideNewsAdmin.admin_nonce
+				}, function(response) {
+					$btn.prop('disabled', false).text('<?php echo esc_js( __( 'Fix Article Sources', 'peptide-news' ) ); ?>');
+					if (response.success) {
+						$result.text(response.data.updated + ' article(s) updated.');
+					} else {
+						$result.text('Error: ' + (response.data || 'Unknown error'));
+					}
+				}).fail(function() {
+					$btn.prop('disabled', false).text('<?php echo esc_js( __( 'Fix Article Sources', 'peptide-news' ) ); ?>');
+					$result.text('Request failed.');
+				});
+			});
+
+			// Generate AI Summaries — loops in batches until all articles are done.
+			// Uses a 3-second delay between batches to respect free-tier rate limits,
+			// and retries up to 3 times when a batch fails before giving up.
+			$('#peptide-generate-summaries').on('click', function() {
+				var $btn = $(this), $result = $('#peptide-summary-result');
+				var totalProcessed = 0;
+				var retries = 0;
+				var maxRetries = 3;
+
+				$btn.prop('disabled', true);
+				$result.text('<?php echo esc_js( __( 'Starting...', 'peptide-news' ) ); ?>');
+
+				function runBatch() {
+					$btn.text('<?php echo esc_js( __( 'Generating...', 'peptide-news' ) ); ?>');
+					$.post(peptideNewsAdmin.ajax_url, {
+						action: 'peptide_news_generate_summaries',
+						nonce: peptideNewsAdmin.admin_nonce
+					}, function(response) {
+						if (response.success) {
+							totalProcessed += response.data.processed;
+							var remaining = response.data.remaining;
+							$result.text(totalProcessed + ' summarized, ' + remaining + ' remaining...');
+
+							if (remaining > 0 && response.data.processed > 0) {
+								// Success — reset retry counter and continue after a delay
+								// to respect the free-tier rate limit (20 req/min).
+								retries = 0;
+								setTimeout(runBatch, 3000);
+							} else if (remaining > 0 && retries < maxRetries) {
+								// No progress — likely rate limited. Wait longer and retry.
+								retries++;
+								$result.text(totalProcessed + ' summarized, ' + remaining + ' remaining... (rate limited, retrying in 10s, attempt ' + retries + '/' + maxRetries + ')');
+								setTimeout(runBatch, 10000);
+							} else {
+								// Done — either all processed or exhausted retries.
+								$btn.prop('disabled', false).text('<?php echo esc_js( __( 'Generate AI Summaries', 'peptide-news' ) ); ?>');
+								if (remaining === 0) {
+									$result.text('Done! ' + totalProcessed + ' article(s) summarized.');
+								} else {
+									var errMsg = totalProcessed + ' summarized. ' + remaining + ' could not be processed.';
+									if (response.data.errors && response.data.errors.length > 0) {
+										errMsg += ' Error: ' + response.data.errors[0];
+									}
+									$result.text(errMsg);
+								}
+							}
+						} else {
+							$btn.prop('disabled', false).text('<?php echo esc_js( __( 'Generate AI Summaries', 'peptide-news' ) ); ?>');
+							$result.text('Error: ' + (response.data || 'Unknown error'));
+						}
+					}).fail(function() {
+						if (retries < maxRetries) {
+							retries++;
+							$result.text(totalProcessed + ' completed. Request failed, retrying in 10s... (attempt ' + retries + '/' + maxRetries + ')');
+							setTimeout(runBatch, 10000);
+						} else {
+							$btn.prop('disabled', false).text('<?php echo esc_js( __( 'Generate AI Summaries', 'peptide-news' ) ); ?>');
+							$result.text('Request failed. ' + totalProcessed + ' completed before failure.');
+						}
+					});
+				}
+
+				runBatch();
+			});
+
+		})(jQuery);
+		</script>
+		<?php
+
+		// Last fetch info.
+		$last_fetch = get_option( 'peptide_news_last_fetch' );
+		if ( $last_fetch ) {
+			$extra_info = '';
+			if ( isset( $last_fetch['filtered_out'] ) && $last_fetch['filtered_out'] > 0 ) {
+				$extra_info .= sprintf(
+					' | %s: %d',
+					esc_html__( 'Filtered out', 'peptide-news' ),
+					$last_fetch['filtered_out']
+				);
+			}
+			if ( isset( $last_fetch['ai_processed'] ) ) {
+				$extra_info .= sprintf(
+					' | %s: %d',
+					esc_html__( 'AI analyzed', 'peptide-news' ),
+					$last_fetch['ai_processed']
+				);
+			}
+			printf(
+				'<p class="description">%s: %s | %s: %d | %s: %d%s</p>',
+				esc_html__( 'Last fetch', 'peptide-news' ),
+				esc_html( $last_fetch['time'] ),
+				esc_html__( 'Found', 'peptide-news' ),
+				intval( $last_fetch['found'] ),
+				esc_html__( 'New stored', 'peptide-news' ),
+				intval( $last_fetch['new_stored'] ),
+				esc_html( $extra_info )
+			);
+		}
+
+		// Settings form.
+		echo '<form method="post" action="options.php">';
+		settings_fields( 'peptide_news_settings_group' );
+		do_settings_sections( 'peptide-news-settings' );
+		submit_button();
+		echo '</form>';
+
+		// Shortcode usage info.
+		echo '<h2>' . esc_html__( 'Usage', 'peptide-news' ) . '</h2>';
+		echo '<p><strong>' . esc_html__( 'Shortcode:', 'peptide-news' ) . '</strong> <code>[peptide_news]</code> ' .
+			esc_html__( 'or', 'peptide-news' ) . ' <code>[peptide_news count="5"]</code></p>';
+		echo '<p><strong>' . esc_html__( 'Widget:', 'peptide-news' ) . '</strong> ' .
+			esc_html__( 'Add "Peptide News" from Appearance > Widgets.', 'peptide-news' ) . '</p>';
+
+		// ── Plugin Log Viewer ──────────────────────────────────────────
+		Peptide_News_Admin_Log_Viewer::render_log_viewer();
+
+		echo '</div>';
+	}
+}

admin/class-pn-admin-settings.php

@@ -0,0 +1,289 @@
+<?php
+declare( strict_types=1 );
+/**
+ * Settings registration and sanitization.
+ *
+ * Registers all WordPress settings (7 sections, 25+ fields) and provides
+ * sanitization callbacks. Field rendering is delegated to
+ * Peptide_News_Admin_Field_Renderers for modularity.
+ *
+ * @since 2.5.0
+ * @see Peptide_News_Admin_Field_Renderers — For field rendering
+ * @see Peptide_News_Encryption — For API key encryption
+ * @see Peptide_News_Cost_Tracker — For budget status in section header
+ */
+class Peptide_News_Admin_Settings {
+
+	/**
+	 * Register all WordPress settings and sections.
+	 *
+	 * @return void
+	 */
+	public function register_settings(): void {
+
+		// --- General section ---
+		add_settings_section(
+			'peptide_news_general',
+			__( 'General Settings', 'peptide-news' ),
+			function () {
+				echo '<p>' . esc_html__( 'Configure how and when peptide news articles are fetched.', 'peptide-news' ) . '</p>';
+			},
+			'peptide-news-settings'
+		);
+
+		$this->add_setting( 'fetch_interval', __( 'Fetch Interval', 'peptide-news' ), 'render_fetch_interval_field', 'peptide_news_general' );
+		$this->add_setting( 'articles_count', __( 'Articles to Display', 'peptide-news' ), 'render_articles_count_field', 'peptide_news_general' );
+		$this->add_setting( 'search_keywords', __( 'Search Keywords', 'peptide-news' ), 'render_search_keywords_field', 'peptide_news_general' );
+
+		// --- RSS section ---
+		add_settings_section(
+			'peptide_news_rss',
+			__( 'RSS Feed Sources', 'peptide-news' ),
+			function () {
+				echo '<p>' . esc_html__( 'Add RSS feed URLs, one per line.', 'peptide-news' ) . '</p>';
+			},
+			'peptide-news-settings'
+		);
+
+		$this->add_setting( 'rss_enabled', __( 'Enable RSS Feeds', 'peptide-news' ), 'render_rss_enabled_field', 'peptide_news_rss' );
+		$this->add_setting( 'rss_feeds', __( 'RSS Feed URLs', 'peptide-news' ), 'render_rss_feeds_field', 'peptide_news_rss' );
+
+		// --- NewsAPI section ---
+		add_settings_section(
+			'peptide_news_newsapi',
+			__( 'NewsAPI.org', 'peptide-news' ),
+			function () {
+				echo '<p>' . esc_html__( 'Optional. Get a free API key at newsapi.org.', 'peptide-news' ) . '</p>';
+			},
+			'peptide-news-settings'
+		);
+
+		$this->add_setting( 'newsapi_enabled', __( 'Enable NewsAPI', 'peptide-news' ), 'render_newsapi_enabled_field', 'peptide_news_newsapi' );
+		$this->add_setting( 'newsapi_key', __( 'API Key', 'peptide-news' ), 'render_newsapi_key_field', 'peptide_news_newsapi' );
+
+		// --- Analytics section ---
+		add_settings_section(
+			'peptide_news_analytics_section',
+			__( 'Analytics', 'peptide-news' ),
+			function () {
+				echo '<p>' . esc_html__( 'Configure click tracking and data retention.', 'peptide-news' ) . '</p>';
+			},
+			'peptide-news-settings'
+		);
+
+		$this->add_setting( 'article_retention', __( 'Article Retention (days)', 'peptide-news' ), 'render_article_retention_field', 'peptide_news_analytics_section' );
+		$this->add_setting( 'analytics_retention', __( 'Analytics Data Retention (days)', 'peptide-news' ), 'render_retention_field', 'peptide_news_analytics_section' );
+		$this->add_setting( 'anonymize_ip', __( 'Anonymize IPs', 'peptide-news' ), 'render_anonymize_ip_field', 'peptide_news_analytics_section' );
+
+		// --- Content Filter section ---
+		add_settings_section(
+			'peptide_news_filter_section',
+			__( 'Content Filter', 'peptide-news' ),
+			function () {
+				echo '<p>' . esc_html__( 'Filter out ads, press releases, and promotional content during fetch. Articles that match the rules are discarded before being saved.', 'peptide-news' ) . '</p>';
+				$last_run = get_option( 'peptide_news_filter_last_run' );
+				if ( $last_run && is_array( $last_run ) ) {
+					printf(
+						'<p class="description"><strong>%s:</strong> %s | %s: %d | %s: %d | %s: %d | %s: %d</p>',
+						esc_html__( 'Last filter run', 'peptide-news' ),
+						esc_html( $last_run['time'] ),
+						esc_html__( 'Evaluated', 'peptide-news' ),
+						absint( $last_run['total'] ),
+						esc_html__( 'Removed', 'peptide-news' ),
+						absint( $last_run['removed'] ),
+						esc_html__( 'LLM checked', 'peptide-news' ),
+						absint( $last_run['llm_checked'] ),
+						esc_html__( 'Passed', 'peptide-news' ),
+						absint( $last_run['passed'] )
+					);
+				}
+			},
+			'peptide-news-settings'
+		);
+
+		$this->add_setting( 'filter_enabled', __( 'Enable Content Filter', 'peptide-news' ), 'render_filter_enabled_field', 'peptide_news_filter_section' );
+		$this->add_setting( 'filter_sensitivity', __( 'Filter Sensitivity', 'peptide-news' ), 'render_filter_sensitivity_field', 'peptide_news_filter_section' );
+		$this->add_setting( 'filter_llm_enabled', __( 'LLM Classification', 'peptide-news' ), 'render_filter_llm_enabled_field', 'peptide_news_filter_section' );
+		$this->add_setting( 'filter_llm_model', __( 'Filter LLM Model', 'peptide-news' ), 'render_filter_llm_model_field', 'peptide_news_filter_section' );
+		$this->add_setting( 'filter_title_keywords', __( 'Title Keywords', 'peptide-news' ), 'render_filter_title_keywords_field', 'peptide_news_filter_section' );
+		$this->add_setting( 'filter_body_keywords', __( 'Body Keywords', 'peptide-news' ), 'render_filter_body_keywords_field', 'peptide_news_filter_section' );
+		$this->add_setting( 'filter_blocked_domains', __( 'Blocked Domains', 'peptide-news' ), 'render_filter_blocked_domains_field', 'peptide_news_filter_section' );
+
+		// --- AI / LLM section ---
+		add_settings_section(
+			'peptide_news_llm_section',
+			__( 'AI Analysis (OpenRouter)', 'peptide-news' ),
+			function () {
+				echo '<p>' . esc_html__( 'Configure LLM-powered keyword extraction and article summarization via OpenRouter.', 'peptide-news' ) . '</p>';
+			},
+			'peptide-news-settings'
+		);
+
+		$this->add_setting( 'llm_enabled', __( 'Enable AI Analysis', 'peptide-news' ), 'render_llm_enabled_field', 'peptide_news_llm_section' );
+		$this->add_setting( 'openrouter_api_key', __( 'OpenRouter API Key', 'peptide-news' ), 'render_openrouter_key_field', 'peptide_news_llm_section' );
+		$this->add_setting( 'llm_keywords_model', __( 'Keywords Model', 'peptide-news' ), 'render_llm_keywords_model_field', 'peptide_news_llm_section' );
+		$this->add_setting( 'llm_summary_model', __( 'Summary Model', 'peptide-news' ), 'render_llm_summary_model_field', 'peptide_news_llm_section' );
+		$this->add_setting( 'llm_max_articles', __( 'Max Articles per Cycle', 'peptide-news' ), 'render_llm_max_articles_field', 'peptide_news_llm_section' );
+
+		// --- Cost Tracking / Budget section ---
+		add_settings_section(
+			'peptide_news_cost_section',
+			__( 'Cost Tracking & Budget', 'peptide-news' ),
+			function () {
+				echo '<p>' . esc_html__( 'Monitor and control LLM API spending. Set a monthly budget to prevent unexpected charges.', 'peptide-news' ) . '</p>';
+				if ( class_exists( 'Peptide_News_Cost_Tracker' ) ) {
+					$month_spend = Peptide_News_Cost_Tracker::get_current_month_spend();
+					$budget      = (float) get_option( 'peptide_news_monthly_budget', 0.0 );
+					printf(
+						'<p class="description"><strong>%s:</strong> $%.4f',
+						esc_html__( 'This month\'s spend', 'peptide-news' ),
+						$month_spend
+					);
+					if ( $budget > 0 ) {
+						printf(
+							' / $%.2f (%.1f%%)',
+							$budget,
+							( $month_spend / $budget ) * 100
+						);
+					}
+					echo '</p>';
+				}
+			},
+			'peptide-news-settings'
+		);
+
+		$this->add_setting( 'monthly_budget', __( 'Monthly Budget (USD)', 'peptide-news' ), 'render_monthly_budget_field', 'peptide_news_cost_section' );
+		$this->add_setting( 'budget_mode', __( 'Budget Enforcement', 'peptide-news' ), 'render_budget_mode_field', 'peptide_news_cost_section' );
+		$this->add_setting( 'cost_retention', __( 'Cost Log Retention (days)', 'peptide-news' ), 'render_cost_retention_field', 'peptide_news_cost_section' );
+	}
+
+	/**
+	 * Helper: register a single setting with a field callback.
+	 *
+	 * @param string $key Setting key (without prefix).
+	 * @param string $label Field label.
+	 * @param string $callback Render method name in Peptide_News_Admin_Field_Renderers.
+	 * @param string $section Settings section ID.
+	 * @return void
+	 */
+	private function add_setting( string $key, string $label, string $callback, string $section ): void {
+		$option_name = "peptide_news_{$key}";
+
+		$sanitize_cb = $this->get_sanitize_callback( $key );
+
+		register_setting( 'peptide_news_settings_group', $option_name, array(
+			'sanitize_callback' => $sanitize_cb,
+		) );
+
+		add_settings_field(
+			$option_name,
+			$label,
+			array( 'Peptide_News_Admin_Field_Renderers', $callback ),
+			'peptide-news-settings',
+			$section
+		);
+	}
+
+	/**
+	 * Return the appropriate sanitize callback for a given setting key.
+	 *
+	 * @param string $key Setting key (without prefix).
+	 * @return callable
+	 */
+	private function get_sanitize_callback( string $key ) {
+		$callbacks = array(
+			'fetch_interval'        => 'sanitize_text_field',
+			'articles_count'        => 'absint',
+			'search_keywords'       => 'sanitize_text_field',
+			'rss_enabled'           => 'absint',
+			'rss_feeds'             => 'sanitize_textarea_field',
+			'newsapi_enabled'       => 'absint',
+			'newsapi_key'           => function ( $value ) {
+				return $this->sanitize_api_key( $value, 'peptide_news_newsapi_key' );
+			},
+			'article_retention'     => 'absint',
+			'analytics_retention'   => 'absint',
+			'anonymize_ip'          => 'absint',
+			'filter_enabled'        => 'absint',
+			'filter_sensitivity'    => 'sanitize_text_field',
+			'filter_llm_enabled'    => 'absint',
+			'filter_llm_model'      => array( $this, 'sanitize_model_id' ),
+			'filter_title_keywords' => 'sanitize_textarea_field',
+			'filter_body_keywords'  => 'sanitize_textarea_field',
+			'filter_blocked_domains' => 'sanitize_textarea_field',
+			'llm_enabled'           => 'absint',
+			'openrouter_api_key'    => function ( $value ) {
+				return $this->sanitize_api_key( $value, 'peptide_news_openrouter_api_key' );
+			},
+			'llm_keywords_model'    => array( $this, 'sanitize_model_id' ),
+			'llm_summary_model'     => array( $this, 'sanitize_model_id' ),
+			'llm_max_articles'      => 'absint',
+			'monthly_budget'        => function ( $value ) {
+				return max( 0.0, (float) $value );
+			},
+			'budget_mode'           => function ( $value ) {
+				$valid = array( 'disabled', 'hard_stop', 'warn_only' );
+				return in_array( $value, $valid, true ) ? $value : 'disabled';
+			},
+			'cost_retention'        => function ( $value ) {
+				return max( 30, absint( $value ) );
+			},
+		);
+
+		return isset( $callbacks[ $key ] ) ? $callbacks[ $key ] : 'sanitize_text_field';
+	}
+
+	/**
+	 * Sanitize and validate an OpenRouter model ID.
+	 *
+	 * @param string $value Raw input.
+	 * @return string Sanitized model ID or default.
+	 */
+	public function sanitize_model_id( string $value ): string {
+		$value = sanitize_text_field( $value );
+		if ( ! empty( $value ) && class_exists( 'Peptide_News_LLM' ) && ! Peptide_News_LLM::is_valid_model( $value ) ) {
+			add_settings_error(
+				'peptide_news_settings_group',
+				'invalid_model',
+				sprintf(
+					/* translators: %s: model ID */
+					__( 'Invalid model ID format: %s. Expected format: provider/model-name', 'peptide-news' ),
+					esc_html( $value )
+				),
+				'error'
+			);
+			return 'google/gemini-2.0-flash-001';
+		}
+		return $value;
+	}
+
+	/**
+	 * Sanitize and encrypt API keys before storage.
+	 *
+	 * If a masked key is submitted (••••••••XXXX format), the existing
+	 * encrypted value is preserved. New plaintext keys are encrypted
+	 * via Peptide_News_Encryption before being written to wp_options.
+	 *
+	 * @param string $value Raw input from the settings form.
+	 * @param string $option_name The wp_options key for this API key.
+	 * @return string Encrypted API key or existing stored value.
+	 */
+	public function sanitize_api_key( string $value, string $option_name ): string {
+		$value = sanitize_text_field( $value );
+		if ( empty( $value ) ) {
+			return '';
+		}
+
+		// If masked format detected (starts with bullets), keep existing stored value.
+		if ( mb_strpos( $value, '••••••' ) === 0 ) {
+			return get_option( $option_name, '' );
+		}
+
+		// Encrypt the new plaintext key before storing.
+		if ( class_exists( 'Peptide_News_Encryption' ) ) {
+			return Peptide_News_Encryption::encrypt( $value );
+		}
+
+		return $value;
+	}
+}

includes/class-peptide-news.php

@@ -44,6 +44,13 @@ class Peptide_News {
 		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'includes/class-peptide-news-logger.php';
 		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'includes/class-peptide-news-content-filter.php';
 		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'includes/class-peptide-news-cost-tracker.php';
+		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'admin/class-pn-admin-assets.php';
+		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'admin/class-pn-admin-menu.php';
+		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'admin/class-pn-admin-field-renderers.php';
+		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'admin/class-pn-admin-settings.php';
+		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'admin/class-pn-admin-log-viewer.php';
+		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'admin/class-pn-admin-settings-page.php';
+		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'admin/class-pn-admin-dashboard-pages.php';
 		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'admin/class-peptide-news-admin.php';
 		require_once PEPTIDE_NEWS_PLUGIN_DIR . 'public/class-peptide-news-public.php';