<?php

namespace App\Console\Commands\AMI;

use Illuminate\Console\Command;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Str;

/**
 * Generate AMI (Asterisk Manager Interface) credentials
 *
 * Generates a fresh username + secret, upserts the manager user directly
 * into the asterisk.manager table, and persists both values to the laravel
 * .env file so the application picks them up without needing a redeploy.
 *
 * Usage:
 *   php artisan ami:generate-credentials           # skip if creds already set
 *   php artisan ami:generate-credentials --force   # always regenerate
 */
class GenerateCredentialsCommand extends Command
{
    protected $signature = 'ami:generate-credentials
                            {--force : Regenerate even if credentials are already set in .env}';

    protected $description = 'Generate AMI manager credentials, register them in asterisk.manager, and write them to .env (non-interactive)';

    /** AMI permissions required by the application */
    protected const AMI_READ  = 'system,call,log,verbose,command,agent,user,config,dtmf,reporting,cdr,dialplan,originate';
    protected const AMI_WRITE = 'system,call,log,verbose,command,agent,user,config,dtmf,reporting,cdr,dialplan,originate';

    public function handle(): int
    {
        $envPath = base_path('.env');

        if (!file_exists($envPath)) {
            $this->error('.env file not found at: ' . $envPath);
            return self::FAILURE;
        }

        // Skip if credentials are already properly configured (unless --force)
        if (!$this->option('force')) {
            $existingUser   = $this->readEnvValue($envPath, 'AMI_USERNAME');
            $existingSecret = $this->readEnvValue($envPath, 'AMI_SECRET');

            if ($existingUser && $existingSecret && $existingUser !== 'theAMIManager') {
                $this->line('AMI credentials are already configured (AMI_USERNAME=' . $existingUser . ').');
                $this->line('Use --force to regenerate.');
                return self::SUCCESS;
            }
        }

        // Remove old manager user if regenerating
        if ($this->option('force')) {
            $oldUser = $this->readEnvValue($envPath, 'AMI_USERNAME');
            if ($oldUser) {
                try {
                    DB::table('asterisk.manager')->where('name', $oldUser)->delete();
                    $this->line('Removed old manager user: ' . $oldUser);
                } catch (\Exception $e) {
                    // Not fatal — table might not have the old user
                }
            }
        }

        // Generate credentials
        // Username: short, readable, no spaces (fits varchar(50))
        $username = 'ccs_ami_' . bin2hex(random_bytes(3));  // e.g. ccs_ami_a1b2c3
        $secret   = Str::random(24);                          // 24-char alphanumeric

        // Step 1 — Register in asterisk.manager (direct DB, no external dependency)
        try {
            $existing = DB::table('asterisk.manager')->where('name', $username)->first();

            if ($existing) {
                DB::table('asterisk.manager')
                    ->where('name', $username)
                    ->update(['secret' => $secret]);
            } else {
                DB::table('asterisk.manager')->insert([
                    'name'         => $username,
                    'secret'       => $secret,
                    'deny'         => '0.0.0.0/0.0.0.0',
                    'permit'       => '127.0.0.1/255.255.255.0',
                    'read'         => self::AMI_READ,
                    'write'        => self::AMI_WRITE,
                    'writetimeout' => 600,
                ]);
            }
        } catch (\Exception $e) {
            $this->error('Failed to register AMI user in asterisk.manager: ' . $e->getMessage());
            \Log::error('ami:generate-credentials failed', ['error' => $e->getMessage()]);
            return self::FAILURE;
        }

        // Step 2 — Write to .env
        try {
            $this->writeEnv($envPath, 'AMI_USERNAME', $username);
            $this->writeEnv($envPath, 'AMI_SECRET',   $secret);
            $this->writeEnv($envPath, 'AMI_PORT',   '5038'); // Ensure port is set (default AMI port)
        } catch (\Exception $e) {
            // Roll back the asterisk.manager entry to keep state consistent
            DB::table('asterisk.manager')->where('name', $username)->delete();
            $this->error('Failed to update .env: ' . $e->getMessage());
            return self::FAILURE;
        }

        // Step 3 — Reload the Asterisk manager module so the new user is live immediately
        $this->reloadManager();

        $this->line('AMI credentials generated successfully.');
        $this->line('  Username : ' . $username);
        $this->line('  Manager  : registered in asterisk.manager');
        $this->line('  .env     : AMI_USERNAME, AMI_SECRET, and AMI_PORT updated');

        \Log::info('ami:generate-credentials completed', ['username' => $username]);

        return self::SUCCESS;
    }

    /**
     * Read a single key's value directly from the .env file (bypasses config cache).
     */
    protected function readEnvValue(string $envPath, string $key): ?string
    {
        $content = file_get_contents($envPath);
        if ($content === false) {
            return null;
        }
        if (preg_match('/^' . preg_quote($key, '/') . '=(.*)$/m', $content, $matches)) {
            return trim($matches[1], " \t\"'");
        }
        return null;
    }

    /**
     * Update or append a key=value pair in the .env file.
     */
    protected function writeEnv(string $envPath, string $key, string $value): void
    {
        $content = file_get_contents($envPath);

        if ($content === false) {
            throw new \RuntimeException('Cannot read .env file');
        }

        // Escape any special characters in the value (spaces, quotes, etc.)
        $escaped = $this->escapeEnvValue($value);
        $line    = $key . '=' . $escaped;

        // Replace existing key (with or without quotes, any value)
        if (preg_match('/^' . preg_quote($key, '/') . '=.*/m', $content)) {
            $content = preg_replace('/^' . preg_quote($key, '/') . '=.*/m', $line, $content);
        } else {
            // Append at the end if the key doesn't exist
            $content = rtrim($content) . "\n" . $line . "\n";
        }

        if (file_put_contents($envPath, $content) === false) {
            throw new \RuntimeException('Cannot write .env file');
        }
    }

    /**
     * Wrap value in double-quotes if it contains spaces or special shell characters.
     */
    protected function escapeEnvValue(string $value): string
    {
        if (preg_match('/[\s"\'\\\\#$]/', $value)) {
            return '"' . addcslashes($value, '"\\') . '"';
        }
        return $value;
    }

    /**
     * Ask Asterisk to reload its manager configuration so the new user goes live.
     */
    protected function reloadManager(): void
    {
        // Try the Asterisk CLI first (covers both native installs and containers)
        $candidates = [
            ['/usr/sbin/asterisk', '-rx', 'manager reload'],
            ['/usr/bin/asterisk',  '-rx', 'manager reload'],
        ];

        foreach ($candidates as $cmd) {
            if (file_exists($cmd[0])) {
                $proc = new \Symfony\Component\Process\Process($cmd);
                $proc->setTimeout(10);
                $proc->run();

                if ($proc->isSuccessful()) {
                    $this->line('  Asterisk manager reloaded.');
                } else {
                    $this->warn('  Asterisk manager reload returned: ' . trim($proc->getOutput() ?: $proc->getErrorOutput()));
                }
                return;
            }
        }

        $this->warn('  Asterisk CLI not found — manager reload skipped. Restart Asterisk manually to activate the new user.');
    }
}