<?php

/**
* Author: Somik Khan
* @copyright 2019
* Permissions: Editing or non-commercial usage
* Prohibition: Sale or commercial usage.
* Updated script: https://somik.org/2019/10/19/php-ip-to-country-script/
*/

class ip2country_lite {
    // Actual DB file
    var $db_file = "./db/ip2location.sqlite";
    
    // Temporary file for IP database zip
    var $tmp_zip = "./db/tmp.zip";    
    
    // Link to ip2loc download
    var $link = "https://download.ip2location.com/lite/IP2LOCATION-LITE-DB1.CSV.ZIP";
    
    function __construct(){
        if(!file_exists($this->db_file)){
            $db_path = basename($this->db_file);
            if(!file_exists($db_path)){
                if(!mkdir($db_path,0755,TRUE)){
                    die("Cannot create \"db\" directory. Please create manually and ensure it is writable by php.");
                }
                else{
                    $this->update();
                }
            }
            else{
                $this->update();
            }
        }
    }
    
    function update(){
        // Get the CSV.ZIP from ip2loc
        $zip_contents = file_get_contents($this->link);
        file_put_contents($this->tmp_zip, $zip_contents);
        // Load the CSV into variable
        $csv_data = file_get_contents("zip://{$this->tmp_zip}#IP2LOCATION-LITE-DB1.CSV");
        // Delete the temp file
        unlink($this->tmp_zip);

        // Process the CSV into array. the format is "18939904","19005439","JP","Japan"
        preg_match_all('#"(\d*?)","(\d*?)","(.*?)","(.*?)"#',$csv_data,$arr_data);

        // Count the number of array items
        $count = count($arr_data[0]);
        // Remove old DB file
        @unlink($this->db_file);
        // Create a new DB file for writing
        $db = new SQLite3($this->db_file, SQLITE3_OPEN_CREATE | SQLITE3_OPEN_READWRITE);
        $db->busyTimeout(5000);

        // Create the table structures
        $db->query('CREATE TABLE IF NOT EXISTS "data" (
                        "start" INTEGER,
                        "end" INTEGER,
                        "country2" VARCHAR,
                        "country" VARCHAR
                    )');

        // Prepare DB insert statemetns but dont write to disk yet
        $db->exec('BEGIN');
        for($i=0;$i<$count;$i++){
            // Add the contents into DB still in memory
            $db->query('INSERT INTO "data" ("start", "end", "country2", "country")
                        VALUES ('.$arr_data[1][$i].', '.$arr_data[2][$i].', "'.$arr_data[3][$i].'", "'.$arr_data[4][$i].'" )');
        }
        // Write changes to DB in disk
        $db->exec('COMMIT');
        // Close the DB and complete.
        $db->close();
        
        echo "Updated";
    }
    
    function getCountry($ip){
        if($ip && file_exists($this->db_file)){
            // Check the IP is provided
            if(preg_match("/^(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/",$ip,$parts)){
                // Convert IP to number by multiplying
                $ip_num = ( pow(256,3) * $parts[1] ) + ( pow(256,2) * $parts[2] ) + ( pow(256,1) * $parts[3] ) + ( pow(256,0) * $parts[4] );
                
                // Load the database and find the IP number
                $db = new SQLite3($this->db_file, SQLITE3_OPEN_READONLY);
                $db->busyTimeout(5000);
                $row = $db->querySingle('SELECT * FROM "data" WHERE "start" < '.$ip_num.' AND "end" > '.$ip_num.' ',1);
                $db->close();
                
                // Output the country
                echo json_encode( array($ip, $row['country'], $row['country2'] ) );
            }
        }
    }
}


// ----------
// Usage
// ----------

$ip = $_REQUEST['ip'];
if($ip){
    $ip2c = new ip2country_lite;
    $ip2c->getCountry($ip);
}
elseif(isset($_REQUEST['update'])){
    $ip2c = new ip2country_lite;
    $ip2c->update();
}