<?php

namespace App\Services;

use App\Models\Setting;
use Illuminate\Http\Client\PendingRequest;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\Http;

/**
 * Live status of the build/deploy pipeline for the currently-cut beta, for the dev Release page.
 * Queries GitHub (tag mirror + CI run) and the configured test server's /version.json. Each step is
 * cached briefly; any failure degrades to 'unknown' (never throws). The read-only GitHub token and the
 * private staging slug come from config (env) and are never rendered or put in a URL.
 */
class PipelineStatus
{
    private const TTL_SECONDS = 15;

    /**
     * @return array{tag:string, steps:array<int,array{key:string,state:string,detail:?string,url:?string}>, ciRunning:bool}|null
     */
    public function forTrackedBeta(): ?array
    {
        $version = (string) config('clusev.version');
        if (! str_contains($version, '-beta')) {
            return null;
        }
        $tag = 'v'.ltrim($version, 'vV');

        $mirror = $this->mirrorStep($tag);
        $ci = $this->ciStep($tag);
        $test = $this->testStep($tag, $version);

        $steps = [
            ['key' => 'tag', 'state' => 'done', 'detail' => $tag, 'url' => null],
            $mirror,
            $ci,
            $test,
        ];

        $ciRunning = $mirror['state'] === 'pending'
            || in_array($ci['state'], ['running', 'pending'], true);

        return ['tag' => $tag, 'steps' => $steps, 'ciRunning' => $ciRunning];
    }

    /** Forget the cached step results so the next read re-fetches (driven by the page poll). */
    public function refresh(): void
    {
        $version = (string) config('clusev.version');
        if (! str_contains($version, '-beta')) {
            return;
        }
        $tag = 'v'.ltrim($version, 'vV');
        foreach (['mirror', 'ci', 'test'] as $step) {
            Cache::forget("clusev:pipeline:{$tag}:{$step}");
        }
    }

    private function github(): PendingRequest
    {
        return Http::timeout(5)
            ->withToken((string) config('clusev.github_token'))
            ->acceptJson()
            ->withHeaders(['User-Agent' => 'Clusev-Panel']);
    }

    /** @return array{key:string,state:string,detail:?string,url:?string} */
    private function mirrorStep(string $tag): array
    {
        return Cache::remember("clusev:pipeline:{$tag}:mirror", self::TTL_SECONDS, function () use ($tag) {
            $token = (string) config('clusev.github_token');
            $slug = (string) config('clusev.staging_slug');
            if ($token === '' || $slug === '') {
                return ['key' => 'mirror', 'state' => 'unknown', 'detail' => null, 'url' => null];
            }
            try {
                $res = $this->github()->get("https://api.github.com/repos/{$slug}/git/refs/tags/{$tag}");
                $state = $res->status() === 404 ? 'pending' : ($res->successful() ? 'done' : 'unknown');

                return ['key' => 'mirror', 'state' => $state, 'detail' => null, 'url' => null];
            } catch (\Throwable $e) {
                report($e);

                return ['key' => 'mirror', 'state' => 'unknown', 'detail' => null, 'url' => null];
            }
        });
    }

    /** @return array{key:string,state:string,detail:?string,url:?string} */
    private function ciStep(string $tag): array
    {
        return Cache::remember("clusev:pipeline:{$tag}:ci", self::TTL_SECONDS, function () use ($tag) {
            $token = (string) config('clusev.github_token');
            $slug = (string) config('clusev.staging_slug');
            if ($token === '' || $slug === '') {
                return ['key' => 'ci', 'state' => 'unknown', 'detail' => null, 'url' => null];
            }
            try {
                $res = $this->github()->get("https://api.github.com/repos/{$slug}/actions/runs", ['per_page' => 30, 'event' => 'push']);
                if (! $res->successful()) {
                    return ['key' => 'ci', 'state' => 'unknown', 'detail' => null, 'url' => null];
                }
                $run = null;
                foreach ((array) ($res->json('workflow_runs') ?? []) as $r) {
                    if (is_array($r) && ($r['head_branch'] ?? null) === $tag) {
                        $run = $r; // workflow_runs are newest-first
                        break;
                    }
                }
                if ($run === null) {
                    return ['key' => 'ci', 'state' => 'pending', 'detail' => null, 'url' => null];
                }
                $status = (string) ($run['status'] ?? '');
                $conclusion = (string) ($run['conclusion'] ?? '');
                $url = is_string($run['html_url'] ?? null) ? $run['html_url'] : null;
                $state = match (true) {
                    in_array($status, ['queued', 'in_progress', 'waiting', 'requested', 'pending'], true) => 'running',
                    $status === 'completed' => $conclusion === 'success' ? 'done' : 'failed',
                    default => 'unknown',
                };

                return ['key' => 'ci', 'state' => $state, 'detail' => null, 'url' => $url];
            } catch (\Throwable $e) {
                report($e);

                return ['key' => 'ci', 'state' => 'unknown', 'detail' => null, 'url' => null];
            }
        });
    }

    /** @return array{key:string,state:string,detail:?string,url:?string} */
    private function testStep(string $tag, string $version): array
    {
        $url = trim((string) Setting::get('pipeline_test_server', ''));
        if ($url === '') {
            return ['key' => 'test', 'state' => 'unset', 'detail' => null, 'url' => null];
        }

        return Cache::remember("clusev:pipeline:{$tag}:test", self::TTL_SECONDS, function () use ($url, $version) {
            try {
                $res = Http::timeout(5)->acceptJson()->get(rtrim($url, '/').'/version.json');
                $running = $res->successful() ? (string) ($res->json('version') ?? '') : '';
                if ($running === '') {
                    return ['key' => 'test', 'state' => 'unknown', 'detail' => null, 'url' => null];
                }
                $state = version_compare(ltrim($running, 'vV'), ltrim($version, 'vV')) >= 0 ? 'done' : 'pending';

                return ['key' => 'test', 'state' => $state, 'detail' => $running, 'url' => null];
            } catch (\Throwable $e) {
                report($e);

                return ['key' => 'test', 'state' => 'unknown', 'detail' => null, 'url' => null];
            }
        });
    }
}