<?php
/**
 * 2UA run API endpoints.
 *
 * @package TwoUA_SEO_Release_Guard
 */

declare(strict_types=1);

namespace TwoUA\SeoReleaseGuard;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

final class RunApiClient {
	private ApiClient $transport;

	public function __construct( ApiClient $transport ) {
		$this->transport = $transport;
	}

	public function capabilities(): RunCapabilities {
		$response     = $this->transport->send_signed( new ApiRequest( 'GET', '/installation', '', null ) );
		$data         = $this->data( $response );
		$capabilities = $data['capabilities'] ?? null;
		if ( ! is_array( $capabilities ) ) {
			throw new ApiException( '2UA returned incomplete run capabilities.' );
		}

		return new RunCapabilities(
			$this->required_int( $capabilities, 'max_urls_per_run' ),
			$this->required_int( $capabilities, 'manual_runs_remaining' ),
			$this->required_bool( $capabilities, 'automatic_runs_enabled' ),
			new RunAccountAccess(
				$this->required_bool( $data, 'connected' ),
				$this->required_int( $capabilities, 'history_days' )
			)
		);
	}

	public function queue( ReleaseEvent $event, ModuleSelection $modules ): RunSummary {
		$request = new ApiRequest(
			'POST',
			'/runs',
			$this->encode( $this->payload( $event, $modules ) ),
			'two-ua-run-' . substr( hash( 'sha256', $event->external_id ), 0, 48 )
		);
		$data    = $this->data( $this->transport->send_signed( $request ) );

		return $this->summary( $data );
	}

	public function status( string $public_id ): RunSummary {
		$path = '/runs/' . rawurlencode( $public_id );
		$data = $this->data( $this->transport->send_signed( new ApiRequest( 'GET', $path, '', null ) ) );

		return $this->summary( $data );
	}

	public function handoff( string $public_id, string $purpose ): RunHandoff {
		$body    = $this->encode(
			array(
				'run_public_id' => $public_id,
				'purpose'       => $purpose,
			)
		);
		$key     = 'two-ua-handoff-' . substr( hash( 'sha256', $public_id . '|' . $purpose ), 0, 48 );
		$data    = $this->data(
			$this->transport->send_signed( new ApiRequest( 'POST', '/handoffs', $body, $key ) )
		);
		$handoff = RunHandoff::from_payload( $data, $public_id, $purpose );
		if ( ! $handoff instanceof RunHandoff ) {
			throw new ApiException( '2UA returned an invalid result link.' );
		}

		return $handoff;
	}

	/** @return array<string, mixed> API boundary payload. */
	private function payload( ReleaseEvent $event, ModuleSelection $modules ): array {
		return array(
			'event'   => array(
				'type'        => $event->type,
				'external_id' => $event->external_id,
				'occurred_at' => $event->occurred_at,
			),
			'modules' => $modules->to_payload(),
			'urls'    => array_map( static fn ( RunUrl $url ): array => $url->to_payload(), $event->urls ),
			'client'  => array(
				'client_version'   => TWO_UA_SEO_RELEASE_GUARD_VERSION,
				'platform_version' => get_bloginfo( 'version' ),
			),
		);
	}

	/** @param array<string, mixed> $payload JSON object payload. */
	private function encode( array $payload ): string {
		$encoded = wp_json_encode( $payload );
		if ( ! is_string( $encoded ) ) {
			throw new ApiException( '2UA request data could not be encoded.' );
		}

		return $encoded;
	}

	/** @return array<string, mixed> Decoded API response data. */
	private function data( ApiResponse $response ): array {
		$decoded = json_decode( $response->body, true );
		$data    = is_array( $decoded ) ? ( $decoded['data'] ?? null ) : null;
		if ( ! is_array( $data ) ) {
			throw new ApiException( '2UA returned an invalid response.' );
		}

		return $data;
	}

	/** @param array<string, mixed> $data Decoded API data. */
	private function required_string( array $data, string $key ): string {
		$value = $data[ $key ] ?? null;
		if ( ! is_string( $value ) || '' === $value ) {
			throw new ApiException( '2UA returned an incomplete run response.' );
		}

		return $value;
	}

	/** @param array<string, mixed> $data Decoded API data. */
	private function required_int( array $data, string $key ): int {
		$value = $data[ $key ] ?? null;
		if ( ! is_int( $value ) ) {
			throw new ApiException( '2UA returned incomplete run capabilities.' );
		}

		return $value;
	}

	/** @param array<string, mixed> $data Decoded API data. */
	private function required_bool( array $data, string $key ): bool {
		$value = $data[ $key ] ?? null;
		if ( ! is_bool( $value ) ) {
			throw new ApiException( '2UA returned incomplete run capabilities.' );
		}

		return $value;
	}

	/** @param array<string, mixed> $data Decoded API data. */
	private function summary( array $data ): RunSummary {
		$summary = RunSummary::from_payload( $data );
		if ( ! $summary instanceof RunSummary ) {
			throw new ApiException( '2UA returned an incomplete run response.' );
		}

		return $summary;
	}
}