<?php

namespace App\Services;

use App\Models\User;
use Illuminate\Support\Facades\DB;

class PartnershipMilestones
{
    /** @return array<int,string> Creation keys are private to the actor who submitted them. */
    public function creationKeys(User $actor, int $partnership, int $room): array
    {
        $keys = [];
        $events = DB::table('partnership_events')->where('partnership_id', $partnership)->where('actor_id', $actor->id)
            ->where('event_type', 'partnership_milestone.changed.v1')->whereRaw("payload->'payload'->>'room_id' = ?", [(string) $room])
            ->whereRaw("payload->'payload'->>'client_key' IS NOT NULL")->get(['payload']);
        foreach ($events as $event) {
            $payload = json_decode($event->payload, true, 512, JSON_THROW_ON_ERROR)['payload'];
            $keys[(int) $payload['milestone_id']] = $payload['client_key'];
        }

        return $keys;
    }

    /** @param array<string,mixed> $data
     * @return array{saved:bool,milestone_id:int,version:int,replayed:bool}
     */
    public function save(User $actor, int $roomId, array $data, ?int $milestone = null): array
    {
        $command = ['title' => $data['title'], 'responsible_id' => (int) $data['responsible_id'], 'due_date' => $data['due_date'] ?? null,
            'status' => $data['status'], 'evidence' => $data['evidence'] ?? null];
        $creationHash = hash('sha256', json_encode($command, JSON_THROW_ON_ERROR));

        return DB::transaction(function () use ($actor, $roomId, $data, $milestone, $command, $creationHash) {
            $exchange = app(PartnershipExchange::class);
            $context = $exchange->room($actor, $roomId);
            abort_unless($exchange->owns($actor, $context['partnership']) || $exchange->owns($actor, $context['interest']), 403);
            $room = DB::table('partnership_rooms')->where('id', $roomId)->lockForUpdate()->first();
            abort_unless($room !== null, 404);
            if ($milestone === null && ($data['client_key'] ?? null)) {
                // The room lock serializes this actor/room key check and its event, including legacy clients.
                $previous = DB::table('partnership_events')->where('partnership_id', $context['partnership']->id)->where('actor_id', $actor->id)
                    ->where('event_type', 'partnership_milestone.changed.v1')->whereRaw("payload->'payload'->>'room_id' = ?", [(string) $roomId])
                    ->whereRaw("payload->'payload'->>'client_key' = ?", [$data['client_key']])->first(['payload']);
                if ($previous) {
                    $payload = json_decode($previous->payload, true, 512, JSON_THROW_ON_ERROR)['payload'];
                    abort_unless($payload['creation_hash'] === $creationHash, 409, 'Chave de criação de marco já utilizada com outro conteúdo.');
                    $saved = DB::table('partnership_milestones')->where('room_id', $roomId)->where('id', $payload['milestone_id'])->first();
                    abort_unless($saved !== null, 409, 'O marco original não está disponível para reconciliar a criação.');

                    return ['saved' => true, 'milestone_id' => (int) $saved->id, 'version' => (int) $saved->version, 'replayed' => true];
                }
            }
            abort_unless(in_array($room->status, ['agreement_recorded', 'agreed', 'execution'], true), 409, 'O estado da sala não permite alterar marcos.');
            $responsible = User::query()->whereKey($command['responsible_id'])->first();
            abort_unless($responsible !== null && ($exchange->owns($responsible, $context['partnership']) || $exchange->owns($responsible, $context['interest'])), 422, 'Responsável deve ser participante identificado.');
            $previousResponsible = null;
            $version = 1;
            if ($milestone !== null) {
                $existing = DB::table('partnership_milestones')->where('room_id', $roomId)->where('id', $milestone)->lockForUpdate()->first();
                abort_unless($existing !== null, 404);
                abort_unless((int) $existing->version === (int) $data['version'], 409, 'O marco foi alterado. Compare com os dados actuais.');
                $previousResponsible = (int) $existing->responsible_id;
                $version = (int) $existing->version + 1;
                DB::table('partnership_milestones')->where('id', $milestone)->update([...$command, 'version' => $version, 'updated_at' => now()]);
            } else {
                $milestone = (int) DB::table('partnership_milestones')->insertGetId([...$command, 'room_id' => $roomId, 'created_at' => now(), 'updated_at' => now()]);
            }
            $metadata = ['room_id' => $roomId, 'milestone_id' => $milestone, 'status' => $command['status'], 'previous_responsible_id' => $previousResponsible, 'responsible_id' => $command['responsible_id']];
            if ($version === 1 && ($data['client_key'] ?? null)) {
                $metadata += ['client_key' => $data['client_key'], 'creation_hash' => $creationHash];
            }
            $exchange->event($context['partnership'], $actor, 'partnership_milestone.changed.v1', $metadata, 'Marco atualizado', [$context['partnership']->user_id, $context['interest']->user_id]);

            return ['saved' => true, 'milestone_id' => $milestone, 'version' => $version, 'replayed' => false];
        });
    }
}