<?php

declare(strict_types=1);

namespace App\Services\TenantConfiguration;

use App\Models\ManagedEnvironment;
use App\Models\ProviderConnection;
use App\Support\Providers\ProviderReasonCodes;
use Illuminate\Support\Facades\Cache;
use Throwable;

final class ExchangePowerShellProductionRunner implements ExchangePowerShellCommandRunner
{
    public function __construct(
        private readonly ExchangePowerShellRuntimeReadinessChecker $runtimeReadiness,
        private readonly ExchangePowerShellCredentialReferenceResolver $credentials,
        private readonly ExchangePowerShellPermissionEvidenceEvaluator $permissions,
        private readonly ExchangePowerShellProcessCommandBuilder $commands,
        private readonly ExchangePowerShellProcessExecutor $executor,
        private readonly ExchangePowerShellOutputGuard $outputGuard,
    ) {}

    public function run(
        ExchangePowerShellCommandContract $commandContract,
        ExchangePowerShellInvocationContext $context,
    ): ExchangePowerShellInvocationResult {
        if ($context->runnerMode !== ExchangePowerShellInvocationGate::RUNNER_MODE_PRODUCTION) {
            return $this->blocked('execution_blocked_runner_mode_invalid', ['runner_mode' => $context->runnerMode]);
        }

        if (! (bool) config(ExchangePowerShellInvocationGate::PRODUCTION_RUNNER_CONFIG_PATH, false)) {
            return $this->blocked('execution_blocked_production_runner_disabled', [
                'runner_mode' => $context->runnerMode,
                'execution_enabled' => false,
            ]);
        }

        $connection = ProviderConnection::query()
            ->whereKey($context->providerConnectionId)
            ->first();
        $environment = ManagedEnvironment::query()
            ->whereKey($context->managedEnvironmentId)
            ->first();

        if (! $connection instanceof ProviderConnection || ! $environment instanceof ManagedEnvironment) {
            return $this->blocked('scope_blocked_provider_connection_missing', ['scope_state' => 'missing']);
        }

        if ((int) $connection->workspace_id !== $context->workspaceId
            || (int) $connection->managed_environment_id !== $context->managedEnvironmentId
            || (int) $environment->workspace_id !== $context->workspaceId
        ) {
            return $this->blocked('scope_blocked_provider_connection_mismatch', ['scope_state' => 'mismatch']);
        }

        $credentialGate = $this->credentials->resolve($connection);

        if (! $credentialGate->allowed) {
            return $this->blockedFromGate($credentialGate);
        }

        $permissionGate = $this->permissions->evaluate($environment, $connection);

        if (! $permissionGate->allowed) {
            return $this->blockedFromGate($permissionGate);
        }

        $runtimePolicy = ExchangePowerShellRuntimePolicy::fromConfig();
        $runtimeGate = $this->runtimeReadiness->check($runtimePolicy);

        if (! $runtimeGate->allowed) {
            return $this->blockedFromGate($runtimeGate);
        }

        $build = $this->commands->build($commandContract, $runtimePolicy);

        if (! $build->successful || ! $build->command instanceof ExchangePowerShellProcessCommand) {
            return $this->blockedFromBuild($build);
        }

        $workspaceLock = Cache::lock('exchange-powershell:workspace:'.$context->workspaceId, $runtimePolicy->lockTtlSeconds);
        $providerLock = Cache::lock('exchange-powershell:provider:'.$context->providerConnectionId, $runtimePolicy->lockTtlSeconds);
        $workspaceAcquired = false;
        $providerAcquired = false;

        try {
            $workspaceAcquired = $workspaceLock->get();

            if (! $workspaceAcquired) {
                return $this->blocked('execution_blocked_concurrency_workspace', [
                    'concurrency_state' => 'workspace_busy',
                ]);
            }

            $providerAcquired = $providerLock->get();

            if (! $providerAcquired) {
                return $this->blocked('execution_blocked_concurrency_provider', [
                    'concurrency_state' => 'provider_busy',
                ]);
            }

            $process = $this->executor->run($build->command);
            $result = $this->outputGuard->guard($process, $commandContract, $runtimePolicy);

            return $this->mergeResultContext($result, array_filter([
                'runner_mode' => ExchangePowerShellInvocationGate::RUNNER_MODE_PRODUCTION,
                'execution_enabled' => true,
                'runtime_state' => $runtimeGate->context['runtime_state'] ?? null,
                'credential_state' => $credentialGate->context['credential_state'] ?? null,
                'permission_evidence_state' => $permissionGate->context['permission_evidence_state'] ?? null,
                'command_builder_state' => $build->context['command_builder_state'] ?? null,
                'concurrency_state' => 'released',
                'duration_ms' => $result->context['duration_ms'] ?? null,
                'item_count' => $result->context['item_count'] ?? null,
            ], static fn (mixed $value): bool => $value !== null && $value !== ''));
        } catch (Throwable) {
            return ExchangePowerShellInvocationResult::failed(
                reasonCode: ProviderReasonCodes::UnknownError,
                failureCode: 'execution_failed_unexpected_exception',
                message: 'Exchange PowerShell production runner failed safely.',
                context: [
                    'runner_mode' => ExchangePowerShellInvocationGate::RUNNER_MODE_PRODUCTION,
                    'execution_enabled' => true,
                    'failure_mode' => 'unexpected_exception',
                    'concurrency_state' => 'release_attempted',
                ],
            );
        } finally {
            if ($providerAcquired) {
                optional($providerLock)->release();
            }

            if ($workspaceAcquired) {
                optional($workspaceLock)->release();
            }
        }
    }

    /**
     * @param  array<string, mixed>  $context
     */
    private function blocked(string $failureCode, array $context = []): ExchangePowerShellInvocationResult
    {
        return ExchangePowerShellInvocationResult::blocked(
            reasonCode: ProviderReasonCodes::ProviderBindingUnsupported,
            failureCode: $failureCode,
            message: 'Exchange PowerShell production runner was blocked.',
            context: $context,
        );
    }

    private function blockedFromGate(ExchangePowerShellGateResult $gate): ExchangePowerShellInvocationResult
    {
        return ExchangePowerShellInvocationResult::blocked(
            reasonCode: $gate->reasonCode ?? ProviderReasonCodes::ProviderBindingUnsupported,
            failureCode: $gate->failureCode ?? 'execution_blocked_gate',
            message: $gate->message ?? 'Exchange PowerShell production runner gate blocked execution.',
            context: [
                'runner_mode' => ExchangePowerShellInvocationGate::RUNNER_MODE_PRODUCTION,
                'execution_enabled' => false,
                ...$gate->context,
            ],
        );
    }

    private function blockedFromBuild(ExchangePowerShellProcessCommandBuilderResult $build): ExchangePowerShellInvocationResult
    {
        return ExchangePowerShellInvocationResult::blocked(
            reasonCode: $build->reasonCode ?? ProviderReasonCodes::ProviderBindingUnsupported,
            failureCode: $build->failureCode ?? 'command_contract_rejected',
            message: $build->message ?? 'Exchange PowerShell command construction was rejected.',
            context: [
                'runner_mode' => ExchangePowerShellInvocationGate::RUNNER_MODE_PRODUCTION,
                'execution_enabled' => false,
                ...$build->context,
            ],
        );
    }

    /**
     * @param  array<string, mixed>  $context
     */
    private function mergeResultContext(ExchangePowerShellInvocationResult $result, array $context): ExchangePowerShellInvocationResult
    {
        if ($result->successful) {
            return ExchangePowerShellInvocationResult::succeeded(
                items: is_array($result->collection) ? $result->collection : [],
                summaryCounts: $result->summaryCounts,
                context: [
                    ...$result->context,
                    ...$context,
                ],
            );
        }

        if ($result->blocked) {
            return ExchangePowerShellInvocationResult::blocked(
                reasonCode: $result->reasonCode ?? ProviderReasonCodes::ProviderBindingUnsupported,
                failureCode: $result->failureCode ?? 'execution_blocked',
                message: $result->message,
                context: [
                    ...$result->context,
                    ...$context,
                ],
            );
        }

        return ExchangePowerShellInvocationResult::failed(
            reasonCode: $result->reasonCode ?? ProviderReasonCodes::UnknownError,
            failureCode: $result->failureCode ?? 'execution_failed',
            message: $result->message,
            summaryCounts: $result->summaryCounts,
            context: [
                ...$result->context,
                ...$context,
            ],
        );
    }
}