<?php

/**
 * @package koko-analytics
 * @license GPL-3.0+
 * @author Danny van Kooten
 */

namespace KokoAnalytics\Admin;

use DateTimeImmutable;

class Data_Export
{
    /** @var \wpdb */
    private $db;

    public function __construct()
    {
        $this->db = $GLOBALS['wpdb'];
    }

    public function action_listener(): void
    {
        if (!current_user_can('manage_koko_analytics')) {
            return;
        }

        check_admin_referer('koko_analytics_export_data');

        $this->run();
    }

    public function run(): void
    {
        // write to HTTP stream
        $date = (new DateTimeImmutable('now', wp_timezone()))->format("Y-m-d");
        $site_url = parse_url(get_site_url(), PHP_URL_HOST);

        header('Content-Type: application/sql');
        header("Content-Disposition: attachment;filename={$site_url}-koko-analytics-export-{$date}.sql");
        $fh = fopen('php://output', 'w');

        // add header - this is also used to detect file is correct during import
        fwrite($fh, "-- Koko Analytics database export from {$date}\n\n");

        $this->export_database_version($fh);
        $this->export_site_stats($fh);
        $this->export_paths($fh);
        $this->export_post_stats($fh);
        $this->export_referrer_urls($fh);
        $this->export_referrer_stats($fh);

        do_action('koko_analytics_write_data_export', $fh);

        fclose($fh);
        exit;
    }

    private function export_database_version($stream): void
    {
        $version = get_option('koko_analytics_version', '0.0.0');
        fwrite($stream, "DELETE FROM {$this->db->options} WHERE option_name = 'koko_analytics_version';\n");
        fwrite($stream, "INSERT INTO {$this->db->options} (option_name, option_value, autoload) VALUES ('koko_analytics_version', '{$version}', 'on');\n");
    }

    private function export_site_stats($stream): void
    {
        // table schema
        fwrite($stream, "DROP TABLE IF EXISTS {$this->db->prefix}koko_analytics_site_stats;\n");
        $create_table_sql = $this->db->get_var("SHOW CREATE TABLE {$this->db->prefix}koko_analytics_site_stats", 1);
        fwrite($stream, $create_table_sql);
        fwrite($stream, ";\n");

        // table contents
        $rows = $this->db->get_results("SELECT * FROM {$this->db->prefix}koko_analytics_site_stats;");
        if (!$rows) {
            return;
        }

        fwrite($stream, "INSERT INTO {$this->db->prefix}koko_analytics_site_stats (date, visitors, pageviews) VALUES ");
        $prefix = '';
        foreach ($rows as $s) {
            fwrite($stream, "{$prefix}(\"{$s->date}\",{$s->visitors},{$s->pageviews})");
            $prefix = ',';
        }
        fwrite($stream, ";\n");
        unset($rows);
    }

    private function export_paths($stream): void
    {
        // table schema
        fwrite($stream, "DROP TABLE IF EXISTS {$this->db->prefix}koko_analytics_paths;\n");
        $create_table_sql = $this->db->get_var("SHOW CREATE TABLE {$this->db->prefix}koko_analytics_paths", 1);
        fwrite($stream, $create_table_sql);
        fwrite($stream, ";\n");

        // table contents
        $rows = $this->db->get_results("SELECT * FROM {$this->db->prefix}koko_analytics_paths;");
        if (!$rows) {
            return;
        }

        fwrite($stream, "INSERT INTO {$this->db->prefix}koko_analytics_paths (id, path) VALUES ");
        $prefix = '';
        foreach ($rows as $s) {
            fprintf($stream, "{$prefix}({$s->id},\"%s\")", esc_sql($s->path));
            $prefix = ',';
        }
        fwrite($stream, ";\n");
        unset($rows);
    }

    private function export_post_stats($stream): void
    {
        // table schema
        fwrite($stream, "DROP TABLE IF EXISTS {$this->db->prefix}koko_analytics_post_stats;\n");
        $create_table_sql = $this->db->get_var("SHOW CREATE TABLE {$this->db->prefix}koko_analytics_post_stats", 1);
        fwrite($stream, $create_table_sql);
        fwrite($stream, ";\n");

        // table contents
        $rows = $this->db->get_results("SELECT * FROM {$this->db->prefix}koko_analytics_post_stats;");
        if (!$rows) {
            return;
        }

        fwrite($stream, "INSERT INTO {$this->db->prefix}koko_analytics_post_stats (date, path_id, post_id, visitors, pageviews) VALUES ");
        $prefix = '';
        foreach ($rows as $s) {
            fwrite($stream, "{$prefix}(\"{$s->date}\",{$s->path_id},{$s->post_id},{$s->visitors},{$s->pageviews})");
            $prefix = ',';
        }
        fwrite($stream, ";\n");
        unset($rows);
    }

    private function export_referrer_urls($stream): void
    {
        // table schema
        fwrite($stream, "DROP TABLE IF EXISTS {$this->db->prefix}koko_analytics_referrer_urls;\n");
        $create_table_sql = $this->db->get_var("SHOW CREATE TABLE {$this->db->prefix}koko_analytics_referrer_urls", 1);
        fwrite($stream, $create_table_sql);
        fwrite($stream, ";\n");

        // table contents
        $rows = $this->db->get_results("SELECT * FROM {$this->db->prefix}koko_analytics_referrer_urls;");
        if (!$rows) {
            return;
        }

        fwrite($stream, "INSERT INTO {$this->db->prefix}koko_analytics_referrer_urls (id, url) VALUES ");
        $prefix = '';
        foreach ($rows as $s) {
            fprintf($stream, "{$prefix}({$s->id},\"%s\")", esc_sql($s->url));
            $prefix = ',';
        }
        fwrite($stream, ";\n");
        unset($rows);
    }

    private function export_referrer_stats($stream): void
    {
        // table schema
        fwrite($stream, "DROP TABLE IF EXISTS {$this->db->prefix}koko_analytics_referrer_stats;\n");
        $create_table_sql = $this->db->get_var("SHOW CREATE TABLE {$this->db->prefix}koko_analytics_referrer_stats", 1);
        fwrite($stream, $create_table_sql);
        fwrite($stream, ";\n");

        // table contents
        $rows = $this->db->get_results("SELECT * FROM {$this->db->prefix}koko_analytics_referrer_stats;");
        if (!$rows) {
            return;
        }

        fwrite($stream, "INSERT INTO {$this->db->prefix}koko_analytics_referrer_stats (date, id, visitors, pageviews) VALUES ");
        $prefix = '';
        foreach ($rows as $s) {
            fwrite($stream, "{$prefix}(\"{$s->date}\",{$s->id},{$s->visitors},{$s->pageviews})");
            $prefix = ',';
        }
        fwrite($stream, ";\n");
        unset($rows);
    }
}