<?php

declare(strict_types=1);

namespace App\Services;

use App\Http\Facade\SignRSA;
use App\Models\InfraManagement;
use Illuminate\Support\Facades\Log;

/**
 * VsphereHostSshService
 *
 * Executes pre-deployed PowerShell scripts on the vSphere Windows host
 * via native SSH (sshpass).  No phpseclib dependency.
 *
 * Scripts in C:/CLISave/ accept 5 positional params:
 *   VM_ID  NEW_PASSWORD  VCENTER_HOST  VCENTER_USER  VCENTER_PASSWORD
 *
 * Scripts only output "SUCCESS" or "FAIL".
 */
final class VsphereHostSshService
{
    private const SCRIPT_DIR     = 'C:\\CLISave'; // backslash required for Windows cmd.exe
    private const SCRIPT_LINUX   = 'changePasswordLinux.ps1';
    private const SCRIPT_WINDOWS = 'changePasswordWindows.ps1';

    private const ASSIGN_DIR            = 'C:\\CLISave\\AssignIP';
    private const SCRIPT_ASSIGN_LINUX   = 'assignIPLinux.ps1';
    private const SCRIPT_ASSIGN_WINDOWS = 'assignIPWindows.ps1';
    private const SCRIPT_VERIFY_LINUX   = 'verifyIPLinux.ps1';
    private const SCRIPT_VERIFY_WINDOWS = 'verifyIPWindows.ps1';

    private const CHANGE_PWD_DIR            = 'C:\\CLISave\\changePassword';
    private const SCRIPT_CHANGE_PWD_LINUX   = 'changePwdLinux.ps1';
    private const SCRIPT_CHANGE_PWD_WINDOWS = 'changePwdWindows.ps1';

    private const CONNECT_TIMEOUT = 20;
    private const MAX_RETRIES     = 5;
    private const RETRY_DELAY     = 5;

    // ─────────────────────────────────────────────────────────────────────────

    /**
     * Run the OS-appropriate PS1 script on the vSphere host.
     *
     * @throws \RuntimeException on SSH failure
     */
    public function changePassword(
        string $vmId,
        string $newPassword,
        string $osFamily,
        string $vcenterHost,
        string $vcenterUser,
        string $vcenterPassword,
    ): string {
        $script = strtoupper($osFamily) === VmProvisionService::OS_WINDOWS
            ? self::SCRIPT_WINDOWS
            : self::SCRIPT_LINUX;
        $powerCliVmId = $this->powerCliVmId($vmId);

        $remoteCmd = strtoupper($osFamily) === VmProvisionService::OS_WINDOWS
            ? $this->windowsPowerShellCommand(self::SCRIPT_DIR, $script, [
                $powerCliVmId,
                $newPassword,
                $vcenterHost,
                $vcenterUser,
                $vcenterPassword,
            ])
            : sprintf(
                'cd %s && powershell -ExecutionPolicy Bypass -NonInteractive -File %s %s %s %s %s %s',
                self::SCRIPT_DIR,
                $script,
                $this->warg($powerCliVmId),
                $this->warg($newPassword),
                $this->warg($vcenterHost),
                $this->warg($vcenterUser),
                $this->warg($vcenterPassword),
            );

        Log::info('VsphereHostSshService: executing script', [
            'vm_id'        => $vmId,
            'script'       => $script,
            'vcenter_host' => $vcenterHost,
        ]);

        $output = $this->sshExec($remoteCmd);

        Log::info('VsphereHostSshService: script output', [
            'vm_id'  => $vmId,
            'output' => trim($output),
        ]);

        return $output;
    }

    // ─────────────────────────────────────────────────────────────────────────

    /**
     * Assign a static IP to the VM guest OS via PS1 script.
     * Calls assignIPLinux.ps1 or assignIPWindows.ps1 in C:\CLISave\AssignIP\.
     *
     * Script params:
     *   VmId IP Gateway Cidr VCenterHost VCenterUser VCenterPassword GuestPassword
     *
     * Script output: JSON {"status":"ok"} or {"status":"error","message":"..."}
     */
    public function assignIp(
        string $vmId,
        string $ip,
        string $gateway,
        string $cidr,
        string $vcenterHost,
        string $vcenterUser,
        string $vcenterPassword,
        string $guestPassword,
        string $osFamily,
        string $dns,
        string $guestUser,
    ): string {
        $isWindows = strtoupper($osFamily) === VmProvisionService::OS_WINDOWS;
        $script    = $isWindows ? self::SCRIPT_ASSIGN_WINDOWS : self::SCRIPT_ASSIGN_LINUX;
        $powerCliVmId = $this->powerCliVmId($vmId);

        $remoteCmd = $isWindows
            ? $this->windowsPowerShellCommand(self::ASSIGN_DIR, $script, [
                $powerCliVmId,
                $ip,
                $gateway,
                $cidr,
                $vcenterHost,
                $vcenterUser,
                $vcenterPassword,
                $guestPassword,
            ])
            : sprintf(
                'cd %s && powershell -ExecutionPolicy Bypass -NonInteractive -File %s %s %s %s %s %s %s %s %s',
                self::ASSIGN_DIR,
                $script,
                $this->warg($powerCliVmId),
                $this->warg($ip),
                $this->warg($gateway),
                $this->warg($cidr),
                $this->warg($vcenterHost),
                $this->warg($vcenterUser),
                $this->warg($vcenterPassword),
                $this->warg($guestPassword),
            );

        Log::info('VsphereHostSshService: executing assignIp', [
            'vm_id'   => $vmId,
            'powercli_vm_id' => $powerCliVmId,
            'ip'      => $ip,
            'script'  => $script,
            'os'      => $osFamily,
        ]);

        $output = $this->sshExec($remoteCmd);

        Log::info('VsphereHostSshService: assignIp output', [
            'vm_id'  => $vmId,
            'ip'     => $ip,
            'output' => trim($output),
        ]);

        return $output;
    }

    /**
     * Verify that an IP is active inside the VM guest OS.
     * Calls verifyIPLinux.ps1 or verifyIPWindows.ps1 in C:\CLISave\AssignIP\.
     *
     * Script params:
     *   VmId IP VCenterHost VCenterUser VCenterPassword GuestPassword
     *
     * Script output: JSON {"status":"ok"} or {"status":"error","message":"..."}
     */
    public function verifyIpInGuest(
        string $vmId,
        string $ip,
        string $vcenterHost,
        string $vcenterUser,
        string $vcenterPassword,
        string $guestPassword,
        string $osFamily,
        string $guestUser,
    ): string {
        $isWindows = strtoupper($osFamily) === VmProvisionService::OS_WINDOWS;
        $script    = $isWindows ? self::SCRIPT_VERIFY_WINDOWS : self::SCRIPT_VERIFY_LINUX;
        $powerCliVmId = $this->powerCliVmId($vmId);

        $remoteCmd = $isWindows
            ? $this->windowsPowerShellCommand(self::ASSIGN_DIR, $script, [
                $powerCliVmId,
                $ip,
                $vcenterHost,
                $vcenterUser,
                $vcenterPassword,
                $guestPassword,
            ])
            : sprintf(
                'cd %s && powershell -ExecutionPolicy Bypass -NonInteractive -File %s %s %s %s %s %s %s',
                self::ASSIGN_DIR,
                $script,
                $this->warg($powerCliVmId),
                $this->warg($ip),
                $this->warg($vcenterHost),
                $this->warg($vcenterUser),
                $this->warg($vcenterPassword),
                $this->warg($guestPassword),
            );

        Log::info('VsphereHostSshService: executing verifyIpInGuest', [
            'vm_id'  => $vmId,
            'powercli_vm_id' => $powerCliVmId,
            'ip'     => $ip,
            'script' => $script,
            'os'     => $osFamily,
        ]);

        $output = $this->sshExec($remoteCmd);

        Log::info('VsphereHostSshService: verifyIpInGuest output', [
            'vm_id'  => $vmId,
            'ip'     => $ip,
            'output' => trim($output),
        ]);

        return $output;
    }

    // ─────────────────────────────────────────────────────────────────────────

    /**
     * Run a command on the vSphere SSH host via sshpass.
     * Retries up to MAX_RETRIES times on connection failure.
     *
     * @throws \RuntimeException
     */
    private function sshExec(string $remoteCmd): string
    {
        $ssh = $this->sshConfig();

        // Full native SSH command executed on local shell
        $sshCmd = sprintf(
            'sshpass -p %s ssh -o StrictHostKeyChecking=no -o ConnectTimeout=%d -p %d %s@%s %s 2>&1',
            escapeshellarg($ssh['password']),
            self::CONNECT_TIMEOUT,
            $ssh['port'],
            escapeshellarg($ssh['username']),
            escapeshellarg($ssh['host']),
            escapeshellarg($remoteCmd),
        );

        for ($attempt = 1; $attempt <= self::MAX_RETRIES; $attempt++) {
            $output = shell_exec($sshCmd);

            if ($output === null) {
                Log::warning('VsphereHostSshService: shell_exec returned null', [
                    'attempt' => $attempt,
                ]);
            } else {
                Log::info('VsphereHostSshService: SSH executed', ['attempt' => $attempt]);
                return $output;
            }

            if ($attempt < self::MAX_RETRIES) {
                sleep(self::RETRY_DELAY);
            }
        }

        throw new \RuntimeException(
            'SSH exec to ' . $ssh['host'] . ' failed after ' . self::MAX_RETRIES . ' attempts',
        );
    }

    /**
     * @return array{host:string, port:int, username:string, password:string}
     */
    private function sshConfig(): array
    {
        $infra = InfraManagement::where('type', 'jumphost')
            ->where('status', true)
            ->first();

        if (!$infra) {
            throw new \RuntimeException('No active jumphost configuration found in InfraManagement.');
        }

        return [
            'host' => $infra->host,
            'port' => (int) ($infra->meta_data['port'] ?? 22),
            'username' => $infra->username,
            'password' => SignRSA::DecryptFunc($infra->password),
        ];
    }

    /**
     * Customer-initiated VM password change.
     *
     * Calls changePwdLinux.ps1 / changePwdWindows.ps1 in C:\CLISave\changePassword\.
     *
     * Param order (matches PS1 declaration):
     *   $vm           vm_id / vmware display name   double-quoted
     *   $password     new password                   single-quoted
     *   $vcenter_host vCenter host                   double-quoted
     *   $vcenter_user vCenter user                   double-quoted
     *   $vcenter_password vCenter password           single-quoted
     *   $guest_password   current guest password     single-quoted
     *
     * PS1 outputs "SUCCESS" or "ERROR".
     */
    public function changePasswordCustomer(
        string $vmId,
        string $newPassword,
        string $currentGuestPassword,
        string $osFamily,
        string $vcenterHost,
        string $vcenterUser,
        string $vcenterPassword,
    ): string {
        $script = strtoupper($osFamily) === VmProvisionService::OS_WINDOWS
            ? self::SCRIPT_CHANGE_PWD_WINDOWS
            : self::SCRIPT_CHANGE_PWD_LINUX;
        $powerCliVmId = $this->powerCliVmId($vmId);

        $remoteCmd = strtoupper($osFamily) === VmProvisionService::OS_WINDOWS
            ? $this->windowsPowerShellCommand(self::CHANGE_PWD_DIR, $script, [
                $powerCliVmId,
                $newPassword,
                $vcenterHost,
                $vcenterUser,
                $vcenterPassword,
                $currentGuestPassword,
            ])
            : sprintf(
                'cd %s && powershell -ExecutionPolicy Bypass -NonInteractive -File %s %s %s %s %s %s %s',
                self::CHANGE_PWD_DIR,
                $script,
                $this->warg($powerCliVmId),
                $this->warg($newPassword),
                $this->warg($vcenterHost),
                $this->warg($vcenterUser),
                $this->warg($vcenterPassword),
                $this->warg($currentGuestPassword),
            );

        Log::info('VsphereHostSshService: changePasswordCustomer', [
            'vm_id'  => $vmId,
            'script' => $script,
            'os'     => $osFamily,
        ]);

        $output = $this->sshExec($remoteCmd);

        Log::info('VsphereHostSshService: changePasswordCustomer output', [
            'vm_id'  => $vmId,
            'output' => trim($output),
        ]);

        return $output;
    }

    // ─────────────────────────────────────────────────────────────────────────

    /**
     * @param array<int, string> $arguments
     */
    private function windowsPowerShellCommand(string $workingDirectory, string $script, array $arguments): string
    {
        return sprintf(
            'cd %s && powershell -ExecutionPolicy Bypass -File %s %s',
            $workingDirectory,
            $script,
            implode(' ', array_map(
                fn (string $argument): string => $this->warg($argument),
                $arguments,
            )),
        );
    }

    /**
     * Windows cmd.exe safe argument: wrap in double quotes, escape inner double quotes.
     */
    private function warg(string $value): string
    {
        return '"' . str_replace('"', '\\"', $value) . '"';
    }

    /**
     * vCenter REST returns MoRef strings like "vm-3340"; PowerCLI scripts build
     * IDs as "VirtualMachine-$vmId", so keep the MoRef intact.
     */
    private function powerCliVmId(string $vmId): string
    {
        return $vmId;
    }

}