<?php

namespace Ulmus\Ldap\Adapter;

use Ulmus\{Adapter\AdapterInterface,
    Common\PdoObject,
    Exception\AdapterConfigurationException,
    Ldap\Entity\User,
    Migration\FieldDefinition,
    Ulmus};

use Ulmus\Ldap\Common\LdapObject;

use function ldap_set_option, ldap_start_tls, ldap_bind, ldap_unbind, ldap_connect, ldap_close, ldap_get_entries;

class Ldap implements \Ulmus\Adapter\AdapterInterface {

    const ALLOWED_ATTRIBUTES = [
        ''
    ];

    public const IDENTIFIER_DN = 101;

    public const IDENTIFIER_FILTER = 102;

    public int $version = 3;

    public bool $encrypt;

    public bool $forceSSL = false;
    
    public array $hosts;
    
    public string $baseDn;

    public string $username;
    
    public string $password;
    
    public string $accountSuffix;

    public string $pathCertCrt;

    public string $pathCertKey;

    public LdapObject $ldapObject;

    public function __construct(
        ? string/*|array*/ $host = null,
        ? string $baseDn = null,
        ? string $username = null,
        ? string $password = null,
        ? string $accountSuffix = null
    ) {
        if ($host) {
            $this->hosts = is_array($host) ? $host : [ $host ];
        }

        if ($baseDn) {
            $this->baseDn = $baseDn;
        }

        if ($username) {
            $this->username = $username;
        }

        if ($password) {
            $this->password = $password;
        }

        if ($accountSuffix) {
            $this->accountSuffix = $accountSuffix;
        }
    }

    public function authenticate(string $dn, string $password) : bool
    {
        $this->ldapObject = $this->getLdapObject();

        return $this->ldapObject->bind($dn, $password);;
    }

    public function connect() : object
    {
        $this->ldapObject = $this->getLdapObject();

        $this->bindUser();

        return $this->ldapObject;
    }

    public function bindUser() : void
    {
        if ( ! $this->ldapObject->bind($this->username, $this->password) ) {
            throw new \Exception("LDAP bind failed with given user $usr.");
        }
    }

    protected function getLdapObject() : LdapObject
    {
        $ldapObject = new LdapObject();

        $ldapObject->connect($this->hosts[0], $this->baseDn);

        $ldapObject->setOptions([
            \LDAP_OPT_PROTOCOL_VERSION => $this->version,
            \LDAP_OPT_REFERRALS => 0,
        ]);

        if ( isset($this->pathCertCrt) && isset($this->pathCertKey) ) {
            $ldapObject->setOptions([
                \LDAP_OPT_X_TLS_CERTFILE => $this->pathCertCrt,
                \LDAP_OPT_X_TLS_KEYFILE => $this->pathCertKey,
            ], false);

            $ldapObject->startTLS();
        }
        elseif ($this->forceSSL) {
            $ldapObject->startTLS();
        }
        
        return $ldapObject;
    }

    public function buildDataSourceName() : string
    {
        return "";
    }
    
    public function setup(array $configuration) : void
    {
        $configuration = array_change_key_case($configuration, \CASE_LOWER);
     
        if ( false === ( $this->hosts = $configuration['hosts'] ?? false ) ) {
            throw new AdapterConfigurationException("Your `host` setting is missing. It is a mandatory parameter for this driver.");
        }
        elseif ( false === ( $this->baseDn = $configuration['base_dn'] ?? false ) ) {
            throw new AdapterConfigurationException("Your `base_dn` setting is missing. The adapter won't connect without it.");
        }
        elseif ( false === ( $this->username = $configuration['username'] ?? false ) ) {
            throw new AdapterConfigurationException("Your `username` is missing from your configuration array");
        }
        elseif ( false === ( $this->password = $configuration['password'] ?? false ) ) {
            throw new AdapterConfigurationException("Your `password` is missing from your configuration array");
        }
        elseif ( false === ( $this->accountSuffix = $configuration['account_suffix'] ?? false ) ) {
            throw new AdapterConfigurationException("Your `account_suffix` is missing from your configuration array");
        }

        if ( false !== ( $configuration['force_ssl'] ?? false ) ) {
            $this->forceSSL = true;
        }

        if ( getenv('DEBUG') ) {
            ldap_set_option(NULL, LDAP_OPT_DEBUG_LEVEL, 7);
        }
    }


    public function writableValue(/* mixed */ $value) /*: mixed*/
    {
        switch (true) {
            case is_object($value):
                return Ulmus::convertObject($value);
        }

        return $value;
    }
    
    public function escapeIdentifier(string $segment, int $type, string $ignore = "") : string
    {
        switch($type) {
            case static::IDENTIFIER_DN:
                return ldap_escape($segment, $ignore, LDAP_ESCAPE_DN);

            case static::IDENTIFIER_FILTER:
            case static::IDENTIFIER_FIELD:
                return ldap_escape($segment, $ignore, LDAP_ESCAPE_FILTER);

            default:
                return ldap_escape($segment, $ignore);
        }
    }

    public function defaultEngine(): ? string
    {
        return null;
    }

    public function repositoryClass() : string
    {
        return \Ulmus\Ldap\Repository::class;
    }

    public function queryBuilderClass() : string
    {
        return \Ulmus\Ldap\QueryBuilder::class;
    }

    public function tableSyntax() : array
    {
        return [
        ];
    }

    public function databaseName() : string
    {
        return $this->baseDn;
    }

    public function whitelistAttributes(array &$parameters) : void
    {
        $parameters = array_intersect_key($parameters, array_flip(static::ALLOWED_ATTRIBUTES));
    }

    public function generateAlterColumn(FieldDefinition $definition, array $field) : string|\Stringable
    {
        return implode(" ", [

        ]);
    }
}