/**
 * Plugin Name: SH Google Ads Longtail Export
 * Description: Erstellt Google-Ads-Keyword-CSV aus eigenen Product-Tag-, Produkt-View- und Awin-Klick-Statistiken.
 * Version: 2.1.0
 */

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

if (!is_admin()) {
    return;
}

/* ---------------------------------------------------
 * ADMIN MENÜ
 * --------------------------------------------------- */

add_action('admin_menu', function () {

    add_submenu_page(
        'sh-eigene-statistiken',
        'Google Ads Longtails',
        'Google Ads Longtails',
        'manage_options',
        'sh-google-ads-longtails',
        'sh_gads_page'
    );

}, 999);

/* ---------------------------------------------------
 * TABLE EXISTS
 * --------------------------------------------------- */

function sh_gads_table_exists($table): bool {

    global $wpdb;

    return (bool)$wpdb->get_var(
        $wpdb->prepare(
            "SHOW TABLES LIKE %s",
            $table
        )
    );
}

/* ---------------------------------------------------
 * UTF-8 CLEAN
 * --------------------------------------------------- */

function sh_gads_clean_keyword($text): string {

    $text = html_entity_decode(
        (string)$text,
        ENT_QUOTES | ENT_HTML5,
        'UTF-8'
    );

    /*
     * WICHTIG:
     * Keine Umlaut-Umwandlung mehr.
     *
     * Also:
     * ä bleibt ä
     * ö bleibt ö
     * ü bleibt ü
     * ß bleibt ß
     *
     * Google Ads kann UTF-8 problemlos.
     */

    $text = trim($text);

    /*
     * lowercase mit UTF-8
     */

    $text = mb_strtolower(
        $text,
        'UTF-8'
    );

    /*
     * Sonderzeichen entfernen
     * Umlaute bleiben erhalten
     */

    $text = preg_replace(
        '/[^\p{L}\p{N}\s\-]/u',
        ' ',
        $text
    );

    /*
     * doppelte Leerzeichen entfernen
     */

    $text = preg_replace(
        '/\s+/u',
        ' ',
        $text
    );

    return trim($text);
}

/* ---------------------------------------------------
 * KEYWORD SCORE
 * --------------------------------------------------- */

function sh_gads_keyword_score($row): float {

    $views = (int)($row->views ?? 0);

    $clicks = (int)($row->clicks ?? 0);

    $products = (int)($row->products ?? 0);

    return
        ($clicks * 20)
        +
        ($views * 2)
        +
        $products;
}

/* ---------------------------------------------------
 * KEYWORDS HOLEN
 * --------------------------------------------------- */

function sh_gads_get_keywords($limit = 300): array {

    global $wpdb;

    $tag_index =
        $wpdb->prefix
        . 'sh_product_tag_visit_index';

    if (
        !sh_gads_table_exists(
            $tag_index
        )
    ) {
        return [];
    }

    $rows = $wpdb->get_results("

        SELECT
            t.term_id,
            t.name,
            t.slug,
            i.views,
            i.clicks,
            i.products

        FROM {$tag_index} i

        INNER JOIN {$wpdb->terms} t
            ON t.term_id = i.term_id

        WHERE
            i.views > 0
            OR
            i.clicks > 0

        ORDER BY
            i.clicks DESC,
            i.views DESC,
            i.products DESC

        LIMIT " . (int)$limit
    );

    $keywords = [];

    foreach ($rows as $row) {

        $kw = sh_gads_clean_keyword(
            $row->name
        );

        if ($kw === '') {
            continue;
        }

        if (
            mb_strlen(
                $kw,
                'UTF-8'
            ) < 3
        ) {
            continue;
        }

        $term_link = get_term_link(
            (int)$row->term_id,
            'product_tag'
        );

        if (
            is_wp_error(
                $term_link
            )
        ) {
            continue;
        }

        $keywords[$kw] = [

            'keyword' => $kw,

            'ad_group' => mb_substr(
                $row->name,
                0,
                80,
                'UTF-8'
            ),

            'url' => $term_link,

            'views' => (int)$row->views,

            'clicks' => (int)$row->clicks,

            'products' => (int)$row->products,

            'score' => sh_gads_keyword_score(
                $row
            ),
        ];
    }

    uasort($keywords, function ($a, $b) {

        return
            $b['score']
            <=>
            $a['score'];
    });

    return array_values($keywords);
}

/* ---------------------------------------------------
 * CSV ESCAPE
 * --------------------------------------------------- */

function sh_gads_csv_escape($value): string {

    $value = (string)$value;

    $value = str_replace(
        '"',
        '""',
        $value
    );

    return '"' . $value . '"';
}

/* ---------------------------------------------------
 * CSV DOWNLOAD
 * --------------------------------------------------- */

function sh_gads_download_csv(
    $match_type = 'both',
    $limit = 300
) {

    $keywords =
        sh_gads_get_keywords($limit);

    $filename =
        'google-ads-longtails-'
        . date('Y-m-d')
        . '.csv';

    /*
     * OUTPUT BUFFER LEEREN
     */

    if (ob_get_length()) {
        ob_clean();
    }

    /*
     * UTF-8 CSV
     */

    header(
        'Content-Type: text/csv; charset=UTF-8'
    );

    header(
        'Content-Disposition: attachment; filename="' . $filename . '"'
    );

    /*
     * UTF-8 BOM
     * Wichtig für Excel + Umlaute
     */

    echo "\xEF\xBB\xBF";

    echo implode(',', [

        'Campaign',
        'Ad group',
        'Keyword',
        'Match type',
        'Final URL',
        'Views',
        'Affiliate Clicks',
        'Products'

    ]) . "\n";

    foreach ($keywords as $item) {

        $rows = [];

        /*
         * PHRASE
         */

        if (
            $match_type === 'phrase'
            ||
            $match_type === 'both'
        ) {

            $rows[] = [

                'match' => 'Phrase',

                'kw' =>
                    '"' .
                    $item['keyword'] .
                    '"',
            ];
        }

        /*
         * EXACT
         */

        if (
            $match_type === 'exact'
            ||
            $match_type === 'both'
        ) {

            $rows[] = [

                'match' => 'Exact',

                'kw' =>
                    '[' .
                    $item['keyword'] .
                    ']',
            ];
        }

        foreach ($rows as $r) {

            echo implode(',', [

                sh_gads_csv_escape(
                    'Gartenhaus Longtail'
                ),

                sh_gads_csv_escape(
                    $item['ad_group']
                ),

                sh_gads_csv_escape(
                    $r['kw']
                ),

                sh_gads_csv_escape(
                    $r['match']
                ),

                sh_gads_csv_escape(
                    $item['url']
                ),

                (int)$item['views'],

                (int)$item['clicks'],

                (int)$item['products'],

            ]) . "\n";
        }
    }

    exit;
}

/* ---------------------------------------------------
 * NEGATIVE KEYWORDS CSV
 * --------------------------------------------------- */

function sh_gads_download_negative_csv() {

    $negative = [

        'kostenlos',
        'gratis',
        'bauplan',
        'bauanleitung',
        'anleitung',
        'pdf',
        'zeichnung',
        'selber bauen',
        'gebraucht',
        'ebay',
        'amazon',
        'obi',
        'hornbach',
        'bauhaus',
        'toom',
        'kleinanzeigen',
        'forum',
        'bilder',
        'foto',
        'ideen',
        'minecraft',
        'spielzeug',
    ];

    if (ob_get_length()) {
        ob_clean();
    }

    header(
        'Content-Type: text/csv; charset=UTF-8'
    );

    header(
        'Content-Disposition: attachment; filename="google-ads-negative-keywords-' . date('Y-m-d') . '.csv"'
    );

    /*
     * UTF-8 BOM
     */

    echo "\xEF\xBB\xBF";

    echo
        "Campaign,Negative keyword,Match type\n";

    foreach ($negative as $kw) {

        echo implode(',', [

            sh_gads_csv_escape(
                'Gartenhaus Longtail'
            ),

            sh_gads_csv_escape($kw),

            sh_gads_csv_escape('Phrase'),

        ]) . "\n";
    }

    exit;
}

/* ---------------------------------------------------
 * EXPORT ROUTEN
 * --------------------------------------------------- */

add_action('admin_init', function () {

    if (
        !current_user_can(
            'manage_options'
        )
    ) {
        return;
    }

    if (isset($_GET['sh_gads_export'])) {

        $match = sanitize_text_field(
            $_GET['match'] ?? 'both'
        );

        $limit = max(
            10,
            min(
                2000,
                (int)(
                    $_GET['limit']
                    ?? 300
                )
            )
        );

        sh_gads_download_csv(
            $match,
            $limit
        );
    }

    if (
        isset(
            $_GET['sh_gads_negative_export']
        )
    ) {

        sh_gads_download_negative_csv();
    }
});

/* ---------------------------------------------------
 * ADMIN SEITE
 * --------------------------------------------------- */

function sh_gads_page() {

    $keywords =
        sh_gads_get_keywords(100);

    echo '<div class="wrap">';

    echo '<h1>
        Google Ads Longtails
    </h1>';

    echo '<p>
        Erstellt automatisch
        Google-Ads-Keywords aus
        deinen echten Produkt-
        und Product-Tag-Daten.
    </p>';

    echo '<p>';

    echo '<a class="button button-primary"
        href="' . esc_url(
            admin_url(
                'admin.php?page=sh-google-ads-longtails&sh_gads_export=1&match=both&limit=300'
            )
        ) . '">
        CSV Phrase + Exact
    </a> ';

    echo '<a class="button"
        href="' . esc_url(
            admin_url(
                'admin.php?page=sh-google-ads-longtails&sh_gads_export=1&match=phrase&limit=300'
            )
        ) . '">
        Nur Phrase
    </a> ';

    echo '<a class="button"
        href="' . esc_url(
            admin_url(
                'admin.php?page=sh-google-ads-longtails&sh_gads_export=1&match=exact&limit=300'
            )
        ) . '">
        Nur Exact
    </a> ';

    echo '<a class="button"
        href="' . esc_url(
            admin_url(
                'admin.php?page=sh-google-ads-longtails&sh_gads_negative_export=1'
            )
        ) . '">
        Negative Keywords
    </a>';

    echo '</p>';

    echo '<h2>
        Vorschau
    </h2>';

    echo '<table class="widefat striped">';

    echo '<thead><tr>';

    echo '<th>#</th>';
    echo '<th>Keyword</th>';
    echo '<th>Phrase</th>';
    echo '<th>Exact</th>';
    echo '<th>Views</th>';
    echo '<th>Klicks</th>';
    echo '<th>Produkte</th>';
    echo '<th>URL</th>';

    echo '</tr></thead><tbody>';

    if (empty($keywords)) {

        echo '<tr>';

        echo '<td colspan="8">
            Keine Daten gefunden.
        </td>';

        echo '</tr>';

    } else {

        $i = 1;

        foreach ($keywords as $item) {

            echo '<tr>';

            echo '<td>'
                . (int)$i
                . '</td>';

            echo '<td>
                <strong>'
                . esc_html(
                    $item['keyword']
                )
                . '</strong>
            </td>';

            echo '<td>
                <code>"'
                . esc_html(
                    $item['keyword']
                )
                . '"</code>
            </td>';

            echo '<td>
                <code>['
                . esc_html(
                    $item['keyword']
                )
                . ']</code>
            </td>';

            echo '<td>'
                . (int)$item['views']
                . '</td>';

            echo '<td>'
                . (int)$item['clicks']
                . '</td>';

            echo '<td>'
                . (int)$item['products']
                . '</td>';

            echo '<td>';

            echo '<a
                href="'
                . esc_url(
                    $item['url']
                )
                . '"
                target="_blank">
                öffnen
            </a>';

            echo '</td>';

            echo '</tr>';

            $i++;
        }
    }

    echo '</tbody></table>';

    echo '</div>';
}