<?php
// File: backend/auth/otp/verify.php
// Unified OTP verification endpoint

require_once __DIR__ . '/../../core/bootstrap.php';
require_once __DIR__ . '/../../functions.php';

// 0. Rate Limiting: 3 محاولات OTP كل 5 دقائق لكل IP
$rateLimiter = new RateLimiter($redis);
$rateLimiter->enforce(RateLimiter::identifier(), 'otp_verify');

// 1. Fetch input parameters
$phone_number = filterRequest("phone_number");
if (empty($phone_number)) {
    $phone_number = filterRequest("receiver");
}

$token_code   = filterRequest("token_code");
if (empty($token_code)) {
    $token_code = filterRequest("token");
}

$user_type    = filterRequest("user_type");
$context      = filterRequest("context");   // token_change | login (default)

// user_type is taken from request only (JWT not trusted without signature verification)

if (empty($phone_number)) {
    jsonError("Phone number is required.");
    exit;
}

if (empty($token_code)) {
    jsonError("Verification token code is required.");
    exit;
}

if (empty($user_type)) {
    if (strpos($_SERVER['REQUEST_URI'], 'driver') !== false) {
        $user_type = 'driver';
    } else {
        $user_type = 'passenger';
    }
}

if (empty($user_type) || !in_array($user_type, ['passenger', 'driver', 'admin', 'service'])) {
    jsonError("User type must be 'passenger', 'driver', 'admin', or 'service'.");
    exit;
}

// 2. Establish DB Connection
try {
    $con = Database::get('main');
} catch (Exception $e) {
    http_response_code(500);
    exit(json_encode(['error' => 'Database connection failed']));
}

// 3. Encrypt data to query
// 4. Verify based on user type
try {
    if ($user_type === 'admin') {
        $sql = "SELECT * FROM token_verification_admin 
                WHERE expiration_time >= NOW() AND verified = 0";
        $stmt = $con->prepare($sql);
        $stmt->execute();
        $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
        
        $matchedRow = null;
        foreach ($rows as $row) {
            $decryptedPhone = $encryptionHelper->decryptData($row['phone_number']);
            $decryptedToken = $encryptionHelper->decryptData($row['token']);
            if ($decryptedPhone === $phone_number && $decryptedToken === $token_code) {
                $matchedRow = $row;
                break;
            }
        }
        
        if ($matchedRow) {
            $deviceNumber = filterRequest("device_number") ?? '';
            // adminUser stores unencrypted phone
            $checkAdmin = $con->prepare("SELECT * FROM adminUser WHERE name = ?");
            $checkAdmin->execute([$phone_number]);
            $now = date("Y-m-d H:i:s");
            
            // Mark token as verified
            $updateToken = $con->prepare("UPDATE token_verification_admin SET verified = 1 WHERE phone_number = ? AND token = ?");
            $updateToken->execute([$matchedRow['phone_number'], $matchedRow['token']]);
            
            if ($checkAdmin->rowCount() > 0) {
                $update = $con->prepare("UPDATE adminUser SET device_number = ?, updated_at = ? WHERE name = ?");
                $update->execute([$deviceNumber, $now, $phone_number]);
                jsonSuccess(["message" => "verified and updated existing admin"]);
            } else {
                $insert = $con->prepare("INSERT INTO adminUser (device_number, name, created_at, updated_at) VALUES (?, ?, ?, ?)");
                $insert->execute([$deviceNumber, $phone_number, $now, $now]);
                jsonSuccess(["message" => "verified and new admin created"]);
            }
        } else {
            jsonError("Your phone number could not be verified or the code is expired. Please try again.");
        }
    } elseif ($user_type === 'service') {
        $sql = "SELECT `id`, `phone_number`, `token_code` FROM `phone_verification_service` 
                WHERE `expiration_time` > NOW() AND `is_verified` = 0";
        $stmt = $con->prepare($sql);
        $stmt->execute();
        $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
        
        $matchedRowId = null;
        foreach ($rows as $row) {
            $decryptedPhone = $encryptionHelper->decryptData($row['phone_number']);
            $decryptedToken = $encryptionHelper->decryptData($row['token_code']);
            if ($decryptedPhone === $phone_number && $decryptedToken === $token_code) {
                $matchedRowId = $row['id'];
                break;
            }
        }
        
        if ($matchedRowId) {
            $sqlUpdate = "UPDATE `phone_verification_service` SET `is_verified` = 1 WHERE `id` = :id";
            $stmtUpd = $con->prepare($sqlUpdate);
            $stmtUpd->bindParam(':id', $matchedRowId, PDO::PARAM_INT);
            $stmtUpd->execute();
            jsonSuccess(null, "Your phone number has been verified.");
        } else {
            jsonError("Your phone number could not be verified or the code is expired. Please try again.");
        }
    } elseif ($user_type === 'driver') {
        if ($context === 'token_change') {
            $sql = "SELECT `id`, `phone_number`, `token` FROM `token_verification_driver` 
                    WHERE `expiration_time` > NOW() AND `verified` = 0";
            $stmt = $con->prepare($sql);
            $stmt->execute();
            $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
            
            $matchedRowId = null;
            foreach ($rows as $row) {
                $decryptedPhone = $encryptionHelper->decryptData($row['phone_number']);
                $decryptedToken = $encryptionHelper->decryptData($row['token']);
                if ($decryptedPhone === $phone_number && $decryptedToken === $token_code) {
                    $matchedRowId = $row['id'];
                    break;
                }
            }
            
            if ($matchedRowId) {
                $sqlUpdate = "UPDATE `token_verification_driver` SET `verified` = 1 WHERE `id` = :id";
                $stmtUpd = $con->prepare($sqlUpdate);
                $stmtUpd->bindParam(':id', $matchedRowId, PDO::PARAM_INT);
                $stmtUpd->execute();
                jsonSuccess(null, "Your phone number has been verified.");
            } else {
                jsonError("Your phone number could not be verified or the code is expired. Please try again.");
            }
        } else {
            $sql = "SELECT `id`, `phone_number`, `token_code` FROM `phone_verification` 
                    WHERE `expiration_time` > NOW() AND `is_verified` = 0";
            $stmt = $con->prepare($sql);
            $stmt->execute();
            $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
            
            $matchedRowId = null;
            foreach ($rows as $row) {
                $decryptedPhone = $encryptionHelper->decryptData($row['phone_number']);
                $decryptedToken = $encryptionHelper->decryptData($row['token_code']);
                if ($decryptedPhone === $phone_number && $decryptedToken === $token_code) {
                    $matchedRowId = $row['id'];
                    break;
                }
            }
            
            if ($matchedRowId) {
                $sqlUpdate = "UPDATE `phone_verification` SET `is_verified` = 1 WHERE `id` = :id";
                $stmtUpd = $con->prepare($sqlUpdate);
                $stmtUpd->bindParam(':id', $matchedRowId, PDO::PARAM_INT);
                $stmtUpd->execute();
                
                // Check registration status
                $isRegistered = false;
                $driverData = null;
                
                $chkStmt = $con->prepare("SELECT id, first_name, last_name, email, phone FROM driver WHERE phone = ?");
                $chkStmt->execute([$encryptionHelper->encryptData($phone_number)]);
                $driver = $chkStmt->fetch(PDO::FETCH_ASSOC);
                
                // Generate driverID for unregistered users (hash of phone)
                $driverID = '';
                if ($driver) {
                    $isRegistered = true;
                    $driver['first_name'] = $encryptionHelper->decryptData($driver['first_name']);
                    $driver['last_name'] = $encryptionHelper->decryptData($driver['last_name']);
                    $driver['email'] = $encryptionHelper->decryptData($driver['email']);
                    $driver['phone'] = $encryptionHelper->decryptData($driver['phone']);
                    $driverData = $driver;
                    $driverID = (string)$driver['id'];
                } else {
                    // driverID ثابت ومشتق من رقم الهاتف (نفس الرقم = نفس الـ ID)
                    $driverID = substr(md5($phone_number), 0, 16);
                }
                
                jsonSuccess([
                    "isRegistered" => $isRegistered,
                    "driver" => $driverData,
                    "driverID" => $driverID
                ], "Your phone number has been verified.");
            } else {
                jsonError("Your phone number could not be verified or the code is expired. Please try again.");
            }
        }
    } else {
        if ($context === 'token_change') {
            $sql = "SELECT `id`, `phone_number`, `token` FROM `token_verification` 
                    WHERE `expiration_time` > NOW() AND `verified` = 0";
            $stmt = $con->prepare($sql);
            $stmt->execute();
            $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
            
            $matchedRowId = null;
            foreach ($rows as $row) {
                $decryptedPhone = $encryptionHelper->decryptData($row['phone_number']);
                $decryptedToken = $encryptionHelper->decryptData($row['token']);
                if ($decryptedPhone === $phone_number && $decryptedToken === $token_code) {
                    $matchedRowId = $row['id'];
                    break;
                }
            }
            
            if ($matchedRowId) {
                $sqlUpdate = "UPDATE `token_verification` SET `verified` = 1 WHERE `id` = :id";
                $stmtUpd = $con->prepare($sqlUpdate);
                $stmtUpd->bindParam(':id', $matchedRowId, PDO::PARAM_INT);
                $stmtUpd->execute();
                jsonSuccess(null, "Your phone number has been verified.");
            } else {
                jsonError("Your phone number could not be verified or the code is expired. Please try again.");
            }
        } else {
            $sql = "SELECT `id`, `phone_number`, `token` FROM `phone_verification_passenger` 
                    WHERE `expiration_time` > NOW() AND `verified` = 0";
            $stmt = $con->prepare($sql);
            $stmt->execute();
            $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
            
            $matchedRowId = null;
            foreach ($rows as $row) {
                $decryptedPhone = $encryptionHelper->decryptData($row['phone_number']);
                $decryptedToken = $encryptionHelper->decryptData($row['token']);
                if ($decryptedPhone === $phone_number && $decryptedToken === $token_code) {
                    $matchedRowId = $row['id'];
                    break;
                }
            }
            
            if ($matchedRowId) {
                $sqlUpdate = "UPDATE `phone_verification_passenger` SET `verified` = 1 WHERE `id` = :id";
                $stmtUpd = $con->prepare($sqlUpdate);
                $stmtUpd->bindParam(':id', $matchedRowId, PDO::PARAM_INT);
                $stmtUpd->execute();
                
                // Check registration status
                $isRegistered = false;
                $passengerData = null;
                
                $chkStmt = $con->prepare("SELECT id, first_name, last_name, email, phone FROM passengers WHERE phone = ?");
                $chkStmt->execute([$encryptionHelper->encryptData($phone_number)]);
                $passenger = $chkStmt->fetch(PDO::FETCH_ASSOC);
                
                if ($passenger) {
                    $isRegistered = true;
                    $passenger['first_name'] = $encryptionHelper->decryptData($passenger['first_name']);
                    $passenger['last_name'] = $encryptionHelper->decryptData($passenger['last_name']);
                    $passenger['email'] = $encryptionHelper->decryptData($passenger['email']);
                    $passenger['phone'] = $encryptionHelper->decryptData($passenger['phone']);
                    $passengerData = $passenger;
                }
                
                jsonSuccess([
                    "isRegistered" => $isRegistered,
                    "passenger" => $passengerData
                ], "Your phone number has been verified.");
            } else {
                jsonError("Your phone number could not be verified or the code is expired. Please try again.");
            }
        }
    }
} catch (PDOException $e) {
    error_log("⚠️ [OTP DB Verify] Error: " . $e->getMessage());
    jsonError("An error occurred during verification. Please try again.");
}