<?php
/**
 * Radio — track history + favourites (v0.5.0).
 *
 * Storage: two per-user `wp_usermeta` keys, separate from `radio_state`
 * so frequent track logging doesn't rewrite the whole state blob.
 *   radio_history    — capped FIFO list of recently played tracks
 *   radio_favourites — uncapped list of user-starred tracks
 *
 * Entry shape:
 *   array(
 *     'artist'     => string,
 *     'title'      => string,
 *     'station'    => string,    // display name e.g. "DEF CON Radio"
 *     'station_id' => string,    // e.g. "soma-defcon"
 *     'at'         => int,       // unix timestamp
 *   )
 */

if ( ! defined( 'ABSPATH' ) ) { exit; }

const RADIO_HISTORY_KEY    = 'radio_history';
const RADIO_FAVOURITES_KEY = 'radio_favourites';
const RADIO_HISTORY_CAP    = 500;

/** Current user's track history (oldest first). */
function radio_get_history( $user_id = 0 ) {
    $user_id = $user_id ? (int) $user_id : get_current_user_id();
    if ( ! $user_id ) { return array(); }
    $h = get_user_meta( $user_id, RADIO_HISTORY_KEY, true );
    return is_array( $h ) ? $h : array();
}

/** Current user's favourited tracks (oldest first). */
function radio_get_favourites( $user_id = 0 ) {
    $user_id = $user_id ? (int) $user_id : get_current_user_id();
    if ( ! $user_id ) { return array(); }
    $f = get_user_meta( $user_id, RADIO_FAVOURITES_KEY, true );
    return is_array( $f ) ? $f : array();
}

/** Normalise raw POSTed track data; returns null on junk input. */
function radio_sanitize_entry( $entry ) {
    if ( ! is_array( $entry ) ) { return null; }
    $artist     = isset( $entry['artist'] )     ? sanitize_text_field( wp_unslash( $entry['artist'] ) )     : '';
    $title      = isset( $entry['title'] )      ? sanitize_text_field( wp_unslash( $entry['title'] ) )      : '';
    $station    = isset( $entry['station'] )    ? sanitize_text_field( wp_unslash( $entry['station'] ) )    : '';
    $station_id = isset( $entry['station_id'] ) ? sanitize_key( wp_unslash( $entry['station_id'] ) )        : '';
    if ( ! $artist || ! $title )                   { return null; }
    if ( strtolower( $artist ) === '(unknown)' )   { return null; } // SomaFM promo / dead-air placeholder
    return array(
        'artist'     => mb_substr( $artist, 0, 200 ),
        'title'      => mb_substr( $title, 0, 200 ),
        'station'    => mb_substr( $station, 0, 100 ),
        'station_id' => $station_id,
        'at'         => time(),
    );
}

/** Dedup signature — artist|title|station_id, lowercased + trimmed. */
function radio_entry_signature( $entry ) {
    $a = isset( $entry['artist'] )     ? $entry['artist']     : '';
    $t = isset( $entry['title'] )      ? $entry['title']      : '';
    $s = isset( $entry['station_id'] ) ? $entry['station_id'] : '';
    return strtolower( trim( $a . '|' . $t . '|' . $s ) );
}

/** Append a track to the user's history, deduped against the last entry
 *  and capped at RADIO_HISTORY_CAP. Returns true if appended. */
function radio_log_track( $entry, $user_id = 0 ) {
    $user_id = $user_id ? (int) $user_id : get_current_user_id();
    if ( ! $user_id ) { return false; }
    $clean = radio_sanitize_entry( $entry );
    if ( ! $clean ) { return false; }

    $history = radio_get_history( $user_id );
    if ( ! empty( $history ) ) {
        $last_sig = radio_entry_signature( $history[ count( $history ) - 1 ] );
        if ( radio_entry_signature( $clean ) === $last_sig ) { return false; }
    }

    $history[] = $clean;
    if ( count( $history ) > RADIO_HISTORY_CAP ) {
        $history = array_slice( $history, -RADIO_HISTORY_CAP );
    }
    update_user_meta( $user_id, RADIO_HISTORY_KEY, $history );
    return true;
}

/** Toggle whether an entry is favourited. Returns the new state
 *  (true = now favourited, false = now unfavourited). */
function radio_toggle_favourite( $entry, $user_id = 0 ) {
    $user_id = $user_id ? (int) $user_id : get_current_user_id();
    if ( ! $user_id ) { return false; }
    $clean = radio_sanitize_entry( $entry );
    if ( ! $clean ) { return false; }
    $sig = radio_entry_signature( $clean );

    $favs  = radio_get_favourites( $user_id );
    $found = -1;
    foreach ( $favs as $i => $f ) {
        if ( radio_entry_signature( $f ) === $sig ) { $found = $i; break; }
    }
    if ( $found >= 0 ) {
        array_splice( $favs, $found, 1 );
        update_user_meta( $user_id, RADIO_FAVOURITES_KEY, $favs );
        return false;
    }
    $favs[] = $clean;
    update_user_meta( $user_id, RADIO_FAVOURITES_KEY, $favs );
    return true;
}

/** Clear the user's history (favourites preserved). */
function radio_clear_history_all( $user_id = 0 ) {
    $user_id = $user_id ? (int) $user_id : get_current_user_id();
    if ( ! $user_id ) { return false; }
    delete_user_meta( $user_id, RADIO_HISTORY_KEY );
    return true;
}

/** URL-build helpers for the four search providers. */
function radio_search_urls( $artist, $title ) {
    $enc = rawurlencode( trim( $artist . ' ' . $title ) );
    return array(
        'spotify'  => 'https://open.spotify.com/search/' . $enc,
        'youtube'  => 'https://www.youtube.com/results?search_query=' . $enc,
        'apple'    => 'https://music.apple.com/search?term=' . $enc,
        'bandcamp' => 'https://bandcamp.com/search?q=' . $enc,
    );
}

/** Render the History admin page (tabs: History / Favourites). */
function radio_render_history_page() {
    if ( ! current_user_can( 'read' ) ) {
        wp_die( esc_html__( 'You do not have permission to view this page.', 'radio' ) );
    }

    $tab = isset( $_GET['tab'] ) ? sanitize_key( wp_unslash( $_GET['tab'] ) ) : 'history'; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- tab-switch only, no state change
    if ( ! in_array( $tab, array( 'history', 'favourites' ), true ) ) { $tab = 'history'; }

    $all_history    = radio_get_history();
    $all_favourites = radio_get_favourites();
    $entries        = ( $tab === 'favourites' ) ? $all_favourites : $all_history;
    $entries        = array_reverse( $entries ); // newest first

    // Set of favourite signatures for fast lookup in the row render.
    $fav_sigs = array();
    foreach ( $all_favourites as $f ) { $fav_sigs[ radio_entry_signature( $f ) ] = true; }

    // Stations present in the current tab → filter dropdown options.
    $stations_in_list = array();
    foreach ( $entries as $e ) {
        if ( ! empty( $e['station_id'] ) && ! isset( $stations_in_list[ $e['station_id'] ] ) ) {
            $stations_in_list[ $e['station_id'] ] = $e['station'];
        }
    }
    asort( $stations_in_list );

    $base_url = admin_url( 'admin.php?page=radio-history' );
    $hist_url = $base_url . '&tab=history';
    $fav_url  = $base_url . '&tab=favourites';
    $nonce    = wp_create_nonce( 'radio_history' );
    ?>
    <div class="wrap radio-history-wrap">
        <h1><?php esc_html_e( 'Radio — Track history', 'radio' ); ?></h1>

        <h2 class="nav-tab-wrapper">
            <a href="<?php echo esc_url( $hist_url ); ?>" class="nav-tab <?php echo $tab === 'history' ? 'nav-tab-active' : ''; ?>">
                <?php esc_html_e( 'History', 'radio' ); ?>
                <span class="radio-tab-count">(<?php echo (int) count( $all_history ); ?>)</span>
            </a>
            <a href="<?php echo esc_url( $fav_url ); ?>" class="nav-tab <?php echo $tab === 'favourites' ? 'nav-tab-active' : ''; ?>">
                ★ <?php esc_html_e( 'Favourites', 'radio' ); ?>
                <span class="radio-tab-count">(<?php echo (int) count( $all_favourites ); ?>)</span>
            </a>
        </h2>

        <?php if ( empty( $entries ) ) : ?>
            <p class="radio-history-empty">
                <?php if ( $tab === 'favourites' ) : ?>
                    <?php esc_html_e( 'No favourites yet — star a track on the History tab to save it here.', 'radio' ); ?>
                <?php else : ?>
                    <?php esc_html_e( 'No tracks logged yet. Play some music in the Radio player — tracks will appear here as they play.', 'radio' ); ?>
                <?php endif; ?>
            </p>
        <?php else : ?>

            <div class="radio-history-toolbar">
                <input type="search" id="radio-history-search" placeholder="<?php esc_attr_e( 'Filter by artist or title…', 'radio' ); ?>" />
                <select id="radio-history-station">
                    <option value=""><?php esc_html_e( 'All stations', 'radio' ); ?></option>
                    <?php foreach ( $stations_in_list as $sid => $sname ) : ?>
                        <option value="<?php echo esc_attr( $sid ); ?>"><?php echo esc_html( $sname ); ?></option>
                    <?php endforeach; ?>
                </select>
                <?php if ( $tab === 'history' ) : ?>
                    <button type="button" id="radio-history-clear" class="button radio-history-clear" data-nonce="<?php echo esc_attr( $nonce ); ?>">
                        🗑 <?php esc_html_e( 'Clear history', 'radio' ); ?>
                    </button>
                <?php endif; ?>
            </div>

            <table class="widefat radio-history-table">
                <thead>
                    <tr>
                        <th class="when"><?php esc_html_e( 'When', 'radio' ); ?></th>
                        <th class="station"><?php esc_html_e( 'Station', 'radio' ); ?></th>
                        <th class="track"><?php esc_html_e( 'Artist — Title', 'radio' ); ?></th>
                        <th class="search"><?php esc_html_e( 'Search', 'radio' ); ?></th>
                        <th class="fav"><span class="screen-reader-text"><?php esc_html_e( 'Favourite', 'radio' ); ?></span>★</th>
                    </tr>
                </thead>
                <tbody>
                <?php foreach ( $entries as $e ) :
                    $sig    = radio_entry_signature( $e );
                    $is_fav = isset( $fav_sigs[ $sig ] );
                    $search = radio_search_urls( $e['artist'], $e['title'] );
                    $ago    = human_time_diff( (int) $e['at'], time() );
                    ?>
                    <tr class="radio-history-row" data-station-id="<?php echo esc_attr( $e['station_id'] ); ?>" data-search="<?php echo esc_attr( strtolower( $e['artist'] . ' ' . $e['title'] ) ); ?>">
                        <td class="when" title="<?php echo esc_attr( wp_date( 'j M Y, H:i', (int) $e['at'] ) ); ?>">
                            <?php printf( esc_html__( '%s ago', 'radio' ), esc_html( $ago ) ); ?>
                        </td>
                        <td class="station"><?php echo esc_html( $e['station'] ); ?></td>
                        <td class="track">
                            <strong><?php echo esc_html( $e['artist'] ); ?></strong> &mdash; <?php echo esc_html( $e['title'] ); ?>
                        </td>
                        <td class="search">
                            <a href="<?php echo esc_url( $search['spotify'] );  ?>" target="_blank" rel="noopener" class="radio-search-link radio-search-link--spotify">Spotify</a>
                            <a href="<?php echo esc_url( $search['youtube'] );  ?>" target="_blank" rel="noopener" class="radio-search-link radio-search-link--youtube">YouTube</a>
                            <a href="<?php echo esc_url( $search['apple'] );    ?>" target="_blank" rel="noopener" class="radio-search-link radio-search-link--apple">Apple</a>
                            <a href="<?php echo esc_url( $search['bandcamp'] ); ?>" target="_blank" rel="noopener" class="radio-search-link radio-search-link--bandcamp">Bandcamp</a>
                        </td>
                        <td class="fav">
                            <button type="button"
                                    class="radio-fav-btn <?php echo $is_fav ? 'is-fav' : ''; ?>"
                                    data-artist="<?php echo esc_attr( $e['artist'] ); ?>"
                                    data-title="<?php echo esc_attr( $e['title'] ); ?>"
                                    data-station="<?php echo esc_attr( $e['station'] ); ?>"
                                    data-station-id="<?php echo esc_attr( $e['station_id'] ); ?>"
                                    data-nonce="<?php echo esc_attr( $nonce ); ?>"
                                    aria-label="<?php echo $is_fav ? esc_attr__( 'Remove from favourites', 'radio' ) : esc_attr__( 'Add to favourites', 'radio' ); ?>">
                                <?php echo $is_fav ? '★' : '☆'; ?>
                            </button>
                        </td>
                    </tr>
                <?php endforeach; ?>
                </tbody>
            </table>

        <?php endif; ?>
    </div>
    <?php
}