<?php

namespace App\Http\Controllers;

use App\Actions\Permissions\PermissionService;
use App\Actions\Tickets\CreateTicketWorklogEntry;
use App\Enums\Permission;
use App\Http\Requests\DestroyProjectTicketTypeRequest;
use App\Http\Requests\StoreProjectNamedSettingRequest;
use App\Http\Requests\StoreProjectTicketTypeRequest;
use App\Http\Requests\StoreTicketFieldDefinitionRequest;
use App\Http\Requests\UpdateProjectNamedSettingRequest;
use App\Http\Requests\UpdateProjectTicketMetadataSettings;
use App\Http\Requests\UpdateProjectTicketTypeRequest;
use App\Http\Requests\UpdateTicketFieldDefinitionRequest;
use App\Models\Project;
use App\Models\Ticket;
use App\Models\TicketFieldDefinition;
use App\Models\TicketLinkType;
use App\Models\TicketPriority;
use App\Models\TicketType;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Arr;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;
use Inertia\Inertia;
use Inertia\Response;

class ProjectTicketMetadataSettingsController extends Controller
{
    public function __construct(
        private readonly CreateTicketWorklogEntry $createTicketWorklogEntry,
        private readonly PermissionService $permissionService,
    ) {}

    public function show(Request $request, Project $project): Response
    {
        $this->abortUnlessCanManage($request, $project);

        return Inertia::render('projects/settings/Metadata', [
            'fieldTypeOptions' => collect(TicketFieldDefinition::FIELD_TYPES)
                ->map(fn (string $fieldType): array => [
                    'label' => ucfirst($fieldType),
                    'value' => $fieldType,
                ])
                ->all(),
            'project' => $project,
            'error' => session('error'),
            'status' => session('status'),
            'ticketFieldDefinitions' => $project->ticketFieldDefinitions()->get(),
            'ticketLinkTypes' => $project->ticketLinkTypes()->get(),
            'ticketPriorities' => $project->ticketPriorities()->get(),
            'ticketTypes' => $project->ticketTypes()->withCount('tickets')->get(),
        ]);
    }

    public function update(UpdateProjectTicketMetadataSettings $request, Project $project): RedirectResponse
    {
        $this->abortUnlessCanManage($request, $project);

        $validated = $request->validated();

        $project->update([
            'show_author' => Arr::get($validated, 'show_author', false),
            'show_story_points' => Arr::get($validated, 'show_story_points', false),
        ]);

        return to_route('projects.settings.metadata', $project)
            ->with('status', 'Settings have been updated.');
    }

    public function storeType(StoreProjectTicketTypeRequest $request, Project $project): RedirectResponse
    {
        $this->abortUnlessCanManage($request, $project);

        $validated = $request->validated();

        $ticketType = DB::transaction(function () use ($project, $validated): TicketType {
            $ticketType = $project->ticketTypes()->create([
                'name' => Arr::get($validated, 'name'),
                'position' => $project->ticketTypes()->count() + 1,
                'is_parent' => Arr::get($validated, 'is_parent', false),
            ]);

            $this->reorderModels(
                $project->ticketTypes()->whereKeyNot($ticketType->id)->get()->values(),
                $ticketType,
                Arr::get($validated, 'position') ?? $project->ticketTypes()->count(),
            );

            return $ticketType;
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$ticketType->name} type was added.");
    }

    public function updateType(
        UpdateProjectTicketTypeRequest $request,
        Project $project,
        TicketType $ticketType,
    ): RedirectResponse {
        $this->abortUnlessCanManage($request, $project);

        $validated = $request->validated();

        DB::transaction(function () use ($project, $validated, $ticketType): void {
            $ticketType->update([
                'name' => Arr::get($validated, 'name'),
            ]);

            $this->reorderModels(
                $project->ticketTypes()->whereKeyNot($ticketType->id)->get()->values(),
                $ticketType,
                Arr::get($validated, 'position'),
            );
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$ticketType->fresh()->name} type was updated.");
    }

    public function destroyType(
        DestroyProjectTicketTypeRequest $request,
        Project $project,
        TicketType $ticketType,
    ): RedirectResponse {
        $this->abortUnlessCanManage($request, $project);

        if ($project->ticketTypes()->count() === 1) {
            return to_route('projects.settings.metadata', $project)
                ->with('error', true)
                ->with('status', 'The last ticket type cannot be deleted.');
        }

        $deletedName = $ticketType->name;
        $validated = $request->validated();

        DB::transaction(function () use ($deletedName, $project, $request, $ticketType, $validated): void {
            $replacementTicketTypeId = Arr::get($validated, 'replacement_ticket_type_id');

            if ($replacementTicketTypeId !== null) {
                $replacementTicketType = $project->ticketTypes()
                    ->findOrFail($replacementTicketTypeId);

                Ticket::query()
                    ->where('project_id', $project->id)
                    ->where('ticket_type_id', $ticketType->id)
                    ->with(['ticketType'])
                    ->get()
                    ->each(function (Ticket $ticket) use ($deletedName, $replacementTicketType, $request): void {
                        $ticket->update([
                            'ticket_type_id' => $replacementTicketType->id,
                        ]);

                        $this->createTicketWorklogEntry->handle(
                            $ticket->fresh(),
                            $request->user(),
                            'updated',
                            "Updated type because {$deletedName} type was deleted.",
                            [
                                'ticket_type' => [
                                    'from' => $deletedName,
                                    'to' => $replacementTicketType->name,
                                ],
                            ],
                        );
                    });
            }

            $ticketType->delete();

            $this->persistOrderedModels($project->ticketTypes()->get()->values());
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$deletedName} type was removed.");
    }

    public function storePriority(StoreProjectNamedSettingRequest $request, Project $project): RedirectResponse
    {
        $this->abortUnlessCanManage($request, $project);

        $validated = $request->validated();
        $name = Arr::get($validated, 'name');
        $position = Arr::get($validated, 'position');

        $ticketPriority = DB::transaction(function () use ($project, $name, $position): TicketPriority {
            $ticketPriority = $project->ticketPriorities()->create([
                'name' => $name,
                'position' => $project->ticketPriorities()->count() + 1,
            ]);

            $this->reorderModels(
                $project->ticketPriorities()->whereKeyNot($ticketPriority->id)->get()->values(),
                $ticketPriority,
                $position ?? $project->ticketPriorities()->count(),
            );

            return $ticketPriority;
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$ticketPriority->name} priority was added.");
    }

    public function updatePriority(
        UpdateProjectNamedSettingRequest $request,
        Project $project,
        TicketPriority $ticketPriority,
    ): RedirectResponse {
        $this->abortUnlessCanManage($request, $project);

        $validated = $request->validated();
        $name = Arr::get($validated, 'name');
        $position = Arr::get($validated, 'position');

        DB::transaction(function () use ($project, $name, $position, $ticketPriority): void {
            $ticketPriority->update([
                'name' => $name,
            ]);

            $this->reorderModels(
                $project->ticketPriorities()->whereKeyNot($ticketPriority->id)->get()->values(),
                $ticketPriority,
                $position,
            );
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$ticketPriority->fresh()->name} priority was updated.");
    }

    public function destroyPriority(
        Request $request,
        Project $project,
        TicketPriority $ticketPriority,
    ): RedirectResponse {
        $this->abortUnlessCanManage($request, $project);

        if ($project->ticketPriorities()->count() === 1) {
            return to_route('projects.settings.metadata', $project)
                ->with('error', true)
                ->with('status', 'The last ticket priority cannot be deleted.');
        }

        $deletedName = $ticketPriority->name;

        DB::transaction(function () use ($project, $ticketPriority): void {
            $ticketPriority->delete();

            $this->persistOrderedModels($project->ticketPriorities()->get()->values());
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$deletedName} priority was removed.");
    }

    public function storeFieldDefinition(
        StoreTicketFieldDefinitionRequest $request,
        Project $project,
    ): RedirectResponse {
        $this->abortUnlessCanManage($request, $project);

        $validated = $request->validated();

        $ticketFieldDefinition = DB::transaction(function () use ($project, $validated): TicketFieldDefinition {
            $ticketFieldDefinition = $project->ticketFieldDefinitions()->create([
                'field_type' => Arr::get($validated, 'field_type'),
                'label' => Arr::get($validated, 'label'),
                'position' => $project->ticketFieldDefinitions()->count() + 1,
            ]);

            $this->reorderModels(
                $project->ticketFieldDefinitions()->whereKeyNot($ticketFieldDefinition->id)->get()->values(),
                $ticketFieldDefinition,
                Arr::get($validated, 'position') ?? $project->ticketFieldDefinitions()->count(),
            );

            return $ticketFieldDefinition;
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$ticketFieldDefinition->label} field was added.");
    }

    public function updateFieldDefinition(
        UpdateTicketFieldDefinitionRequest $request,
        Project $project,
        TicketFieldDefinition $ticketFieldDefinition,
    ): RedirectResponse {
        $this->abortUnlessCanManage($request, $project);

        $validated = $request->validated();

        DB::transaction(function () use ($project, $ticketFieldDefinition, $validated): void {
            $ticketFieldDefinition->update([
                'field_type' => Arr::get($validated, 'field_type'),
                'label' => Arr::get($validated, 'label'),
            ]);

            $this->reorderModels(
                $project->ticketFieldDefinitions()->whereKeyNot($ticketFieldDefinition->id)->get()->values(),
                $ticketFieldDefinition,
                Arr::get($validated, 'position'),
            );
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$ticketFieldDefinition->fresh()->label} field was updated.");
    }

    public function destroyFieldDefinition(
        Request $request,
        Project $project,
        TicketFieldDefinition $ticketFieldDefinition,
    ): RedirectResponse {
        $this->abortUnlessCanManage($request, $project);

        $deletedLabel = $ticketFieldDefinition->label;

        DB::transaction(function () use ($project, $ticketFieldDefinition): void {
            $ticketFieldDefinition->delete();

            $this->persistOrderedModels($project->ticketFieldDefinitions()->get()->values());
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$deletedLabel} field was removed.");
    }

    public function storeLinkType(StoreProjectNamedSettingRequest $request, Project $project): RedirectResponse
    {
        $validated = $request->validated();
        $name = Arr::get($validated, 'name');
        $position = Arr::get($validated, 'position');

        $this->abortUnlessCanManage($request, $project);

        $ticketLinkType = DB::transaction(function () use ($project, $position, $name): TicketLinkType {
            $ticketLinkType = $project->ticketLinkTypes()->create([
                'label' => $name,
                'position' => $project->ticketLinkTypes()->count() + 1,
            ]);

            $this->reorderModels(
                $project->ticketLinkTypes()->whereKeyNot($ticketLinkType->id)->get()->values(),
                $ticketLinkType,
                $position ?? $project->ticketLinkTypes()->count(),
            );

            return $ticketLinkType;
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$ticketLinkType->label} link type was added.");
    }

    public function updateLinkType(
        UpdateProjectNamedSettingRequest $request,
        Project $project,
        TicketLinkType $ticketLinkType,
    ): RedirectResponse {

        $validated = $request->validated();
        $name = Arr::get($validated, 'name');
        $position = Arr::get($validated, 'position');

        $this->abortUnlessCanManage($request, $project);

        DB::transaction(function () use ($project, $name, $position, $ticketLinkType): void {
            $ticketLinkType->update([
                'label' => $name,
            ]);

            $this->reorderModels(
                $project->ticketLinkTypes()->whereKeyNot($ticketLinkType->id)->get()->values(),
                $ticketLinkType,
                $position,
            );
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$ticketLinkType->fresh()->label} link type was updated.");
    }

    public function destroyLinkType(
        Request $request,
        Project $project,
        TicketLinkType $ticketLinkType,
    ): RedirectResponse {
        $this->abortUnlessCanManage($request, $project);

        $deletedLabel = $ticketLinkType->label;

        DB::transaction(function () use ($project, $ticketLinkType): void {
            $ticketLinkType->delete();

            $this->persistOrderedModels($project->ticketLinkTypes()->get()->values());
        });

        return to_route('projects.settings.metadata', $project)
            ->with('status', "{$deletedLabel} link type was removed.");
    }

    private function abortUnlessCanManage(Request $request, Project $project): void
    {
        abort_unless(
            $this->permissionService->allows($request->user(), Permission::ProjectAdmin, $project),
            403,
        );
    }

    /**
     * @param  Collection<int, Model>  $models
     */
    private function persistOrderedModels(Collection $models): void
    {
        $temporaryOffset = ((int) $models->max('position')) + $models->count() + 1;

        $models->each(function (Model $model, int $index) use ($temporaryOffset): void {
            $model->forceFill([
                'position' => $temporaryOffset + $index,
            ])->saveQuietly();
        });

        $models->each(function (Model $model, int $index): void {
            $model->forceFill([
                'position' => $index + 1,
            ])->saveQuietly();
        });
    }

    /**
     * @param  Collection<int, Model>  $existingModels
     */
    private function reorderModels(Collection $existingModels, Model $movingModel, int $desiredPosition): void
    {
        $insertAt = max(0, min($desiredPosition - 1, $existingModels->count()));

        $existingModels->splice($insertAt, 0, [$movingModel]);

        $this->persistOrderedModels($existingModels->values());
    }
}