<?php

namespace App\Http\Controllers;

use App\Actions\Git\BuildSuggestedTicketBranchName;
use App\Actions\Git\ResolveTicketBranchMatches;
use App\Actions\Git\ResolveTicketPullRequestMatches;
use App\Actions\Permissions\PermissionService;
use App\Actions\Tickets\UpdateProjectTicket;
use App\Enums\Permission;
use App\Http\Requests\UpdateProjectTicketRequest;
use App\Models\Project;
use App\Models\Ticket;
use App\Models\TicketLink;
use App\Models\User;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Arr;
use Inertia\Inertia;
use Inertia\Response;

class ProjectTicketController extends Controller
{
    public function __construct(
        private readonly BuildSuggestedTicketBranchName $buildSuggestedTicketBranchName,
        private readonly PermissionService $permissionService,
        private readonly ResolveTicketBranchMatches $resolveTicketBranchMatches,
        private readonly ResolveTicketPullRequestMatches $resolveTicketPullRequestMatches,
        private readonly UpdateProjectTicket $updateProjectTicket,
    ) {}

    public function show(Request $request, Project $project, Ticket $ticket): Response
    {
        $user = $request->user();

        abort_unless(
            $this->permissionService->allows($user, Permission::ProjectRead, $project),
            403,
        );

        $canEditTicket = $this->permissionService->allows($user, Permission::ProjectWrite, $project);
        $canManageProject = $this->permissionService->allows($user, Permission::ProjectAdmin, $project);
        $excludedParentIds = [$ticket->id, ...$this->descendantIds($ticket)];
        $displayTicket = $ticket->load([
            'assignee',
            'author',
            'fieldValues.ticketFieldDefinition',
            'fieldValues.userValue',
            'parentTicket',
            'ticketPriority',
            'ticketStatus.boardColumn',
            'ticketType',
            'worklogEntries.actor',
        ]);

        if (! $project->show_author && ! $canManageProject) {
            $displayTicket->setRelation('author', null);
            $displayTicket->author_user_id = null;
        }

        return Inertia::render('projects/Ticket', [
            'canEditTicket' => $canEditTicket,
            'canManageProject' => $canManageProject,
            'childTicketTree' => $this->buildChildTicketTree($ticket),
            'linkedTickets' => $this->linkedTickets($ticket),
            'parentTicketOptions' => Ticket::query()
                ->where('project_id', $project->id)
                ->whereNotIn('id', $excludedParentIds)
                ->whereHas('ticketType', fn ($query) => $query->where('is_parent', true))
                ->orderByDesc('sequence_number')
                ->get()
                ->map(fn (Ticket $parentTicket): array => [
                    'id' => $parentTicket->id,
                    'ticket_key' => $parentTicket->ticket_key,
                    'title' => $parentTicket->title,
                ]),
            'project' => $project,
            'repositoryBranches' => $this->resolveTicketBranchMatches->handle(
                $user,
                $project,
                $ticket,
            ),
            'repositoryPullRequests' => $this->resolveTicketPullRequestMatches->handle(
                $user,
                $project,
                $ticket,
            ),
            'status' => session('status'),
            'suggestedBranchName' => $this->buildSuggestedTicketBranchName->handle($ticket),
            'ticket' => $displayTicket,
            'ticketFieldDefinitions' => $project->ticketFieldDefinitions()->get(),
            'ticketLinkOptions' => Ticket::query()
                ->where('project_id', $project->id)
                ->whereKeyNot($ticket->id)
                ->orderByDesc('sequence_number')
                ->get()
                ->map(fn (Ticket $linkedTicket): array => [
                    'id' => $linkedTicket->id,
                    'ticket_key' => $linkedTicket->ticket_key,
                    'title' => $linkedTicket->title,
                ]),
            'ticketLinkTypes' => $project->ticketLinkTypes()->get(),
            'ticketPriorities' => $project->ticketPriorities()->get(),
            'ticketTypes' => $project->ticketTypes()->get(),
            'users' => User::query()
                ->orderBy('name')
                ->get(),
        ]);
    }

    public function update(
        UpdateProjectTicketRequest $request,
        Project $project,
        Ticket $ticket,
    ): RedirectResponse {

        $user = $request->user();
        abort_unless(
            $this->permissionService->allows($user, Permission::ProjectWrite, $project),
            403,
        );

        $validated = $request->validated();
        $fieldValues = Arr::get($validated, 'field_values', []);
        $ticketAttributes = [
            'acceptance_criteria' => Arr::get($validated, 'acceptance_criteria'),
            'assignee_user_id' => Arr::exists($validated, 'assignee_user_id')
                ? Arr::get($validated, 'assignee_user_id')
                : $ticket->assignee_user_id,
            'author_user_id' => Arr::exists($validated, 'author_user_id')
                ? Arr::get($validated, 'author_user_id')
                : $ticket->author_user_id,
            'blocked_comment' => Arr::get($validated, 'blocked_comment'),
            'description' => Arr::get($validated, 'description'),
            'is_blocked' => Arr::get($validated, 'is_blocked', false),
            'parent_ticket_id' => Arr::get($validated, 'parent_ticket_id'),
            'story_points' => Arr::exists($validated, 'story_points')
                ? Arr::get($validated, 'story_points')
                : $ticket->story_points,
            'ticket_priority_id' => Arr::get($validated, 'ticket_priority_id'),
            'ticket_type_id' => Arr::get($validated, 'ticket_type_id'),
            'title' => Arr::get($validated, 'title'),
        ];

        $wasUpdated = $this->updateProjectTicket->handle(
            $ticket,
            $user,
            $ticketAttributes,
            $fieldValues,
        );

        $statusMessage = $wasUpdated
            ? "{$ticket->ticket_key} was updated."
            : 'No ticket changes were detected.';

        return to_route('projects.tickets.show', [$project, $ticket])
            ->with('status', $statusMessage);
    }

    /**
     * @return array<int, array{
     *     children: array<int, mixed>,
     *     id: int,
     *     ticket_key: string,
     *     ticket_type_name: string|null,
     *     title: string
     * }>
     */
    private function buildChildTicketTree(Ticket $ticket): array
    {
        return $ticket->childTickets()
            ->with('ticketType')
            ->get()
            ->map(fn (Ticket $childTicket): array => [
                'children' => $this->buildChildTicketTree($childTicket),
                'id' => $childTicket->id,
                'ticket_key' => $childTicket->ticket_key,
                'ticket_type_name' => $childTicket->ticketType?->name,
                'title' => $childTicket->title,
            ])
            ->all();
    }

    /**
     * @return array<int, int>
     */
    private function descendantIds(Ticket $ticket): array
    {
        return $ticket->childTickets()
            ->get()
            ->flatMap(function (Ticket $childTicket): array {
                return [$childTicket->id, ...$this->descendantIds($childTicket)];
            })
            ->values()
            ->all();
    }

    /**
     * @return array<int, array{
     *     created_at: string|null,
     *     id: int,
     *     linked_ticket: array{id: int, ticket_key: string, title: string},
     *     source_ticket_id: int,
     *     target_ticket_id: int,
     *     ticket_link_type: mixed,
     *     ticket_link_type_id: int,
     *     updated_at: string|null
     * }>
     */
    private function linkedTickets(Ticket $ticket): array
    {
        return TicketLink::query()
            ->with(['sourceTicket', 'targetTicket', 'ticketLinkType'])
            ->where(function ($query) use ($ticket): void {
                $query
                    ->where('source_ticket_id', $ticket->id)
                    ->orWhere('target_ticket_id', $ticket->id);
            })
            ->orderBy('id')
            ->get()
            ->map(function (TicketLink $ticketLink) use ($ticket): array {
                $linkedTicket = $ticketLink->source_ticket_id === $ticket->id
                    ? $ticketLink->targetTicket
                    : $ticketLink->sourceTicket;

                return [
                    'created_at' => $ticketLink->created_at?->toISOString(),
                    'id' => $ticketLink->id,
                    'linked_ticket' => [
                        'id' => $linkedTicket->id,
                        'ticket_key' => $linkedTicket->ticket_key,
                        'title' => $linkedTicket->title,
                    ],
                    'source_ticket_id' => $ticketLink->source_ticket_id,
                    'target_ticket_id' => $ticketLink->target_ticket_id,
                    'ticket_link_type' => $ticketLink->ticketLinkType,
                    'ticket_link_type_id' => $ticketLink->ticket_link_type_id,
                    'updated_at' => $ticketLink->updated_at?->toISOString(),
                ];
            })
            ->all();
    }
}