<?php

namespace Filament\Forms\Components\Concerns;

use Closure;
use Filament\Forms\Components\Component;
use Filament\Forms\Get;
use Filament\Forms\Set;
use Illuminate\Contracts\Support\Arrayable;
use Illuminate\Support\Arr;
use Illuminate\Support\Str;
use Livewire\Livewire;

use function Livewire\store;

trait HasState
{
    protected ?Closure $afterStateHydrated = null;

    /**
     * @var array<Closure>
     */
    protected array $afterStateUpdated = [];

    protected ?Closure $beforeStateDehydrated = null;

    protected mixed $defaultState = null;

    protected ?Closure $dehydrateStateUsing = null;

    protected ?Closure $mutateDehydratedStateUsing = null;

    protected ?Closure $mutateStateForValidationUsing = null;

    protected bool $hasDefaultState = false;

    protected bool | Closure $isDehydrated = true;

    protected bool | Closure $isDehydratedWhenHidden = false;

    protected ?string $statePath = null;

    protected string $cachedAbsoluteStatePath;

    /**
     * @var string | array<string> | Closure | null
     */
    protected string | array | Closure | null $stripCharacters = null;

    /**
     * @var array<string>
     */
    protected array $cachedStripCharacters;

    public function afterStateHydrated(?Closure $callback): static
    {
        $this->afterStateHydrated = $callback;

        return $this;
    }

    public function clearAfterStateUpdatedHooks(): static
    {
        $this->afterStateUpdated = [];

        return $this;
    }

    public function afterStateUpdated(?Closure $callback): static
    {
        $this->afterStateUpdated[] = $callback;

        return $this;
    }

    public function beforeStateDehydrated(?Closure $callback): static
    {
        $this->beforeStateDehydrated = $callback;

        return $this;
    }

    public function callAfterStateHydrated(): static
    {
        if ($callback = $this->afterStateHydrated) {
            $this->evaluate($callback);
        }

        return $this;
    }

    public function callAfterStateUpdated(): static
    {
        foreach ($this->afterStateUpdated as $callback) {
            $runId = spl_object_id($callback) . md5(json_encode($this->getState()));

            if (store($this)->has('executedAfterStateUpdatedCallbacks', iKey: $runId)) {
                continue;
            }

            $this->callAfterStateUpdatedHook($callback);

            store($this)->push('executedAfterStateUpdatedCallbacks', value: $runId, iKey: $runId);
        }

        return $this;
    }

    protected function callAfterStateUpdatedHook(Closure $hook): void
    {
        $this->evaluate($hook, [
            'old' => $this->getOldState(),
        ]);
    }

    public function callBeforeStateDehydrated(): static
    {
        if ($callback = $this->beforeStateDehydrated) {
            $this->evaluate($callback);
        }

        return $this;
    }

    public function default(mixed $state): static
    {
        $this->defaultState = $state;
        $this->hasDefaultState = true;

        return $this;
    }

    public function dehydrated(bool | Closure $condition = true): static
    {
        $this->isDehydrated = $condition;

        return $this;
    }

    public function dehydratedWhenHidden(bool | Closure $condition = true): static
    {
        $this->isDehydratedWhenHidden = $condition;

        return $this;
    }

    public function formatStateUsing(?Closure $callback): static
    {
        $this->afterStateHydrated(fn (Component $component) => $component->state($component->evaluate($callback)));

        return $this;
    }

    /**
     * @return array<string, mixed>
     */
    public function getStateToDehydrate(): array
    {
        if ($callback = $this->dehydrateStateUsing) {
            return [$this->getStatePath() => $this->evaluate($callback)];
        }

        return [$this->getStatePath() => $this->getState()];
    }

    /**
     * @param  array<string, mixed>  $state
     */
    public function dehydrateState(array &$state, bool $isDehydrated = true): void
    {
        if (! ($isDehydrated && $this->isDehydrated())) {
            if ($this->hasStatePath()) {
                Arr::forget($state, $this->getStatePath());

                return;
            }

            // If the component is not dehydrated, but it has child components,
            // we need to dehydrate the child component containers while
            // informing them that they are not dehydrated, so that their
            // child components get removed from the state.
            foreach ($this->getChildComponentContainers() as $container) {
                $container->dehydrateState($state, isDehydrated: false);
            }

            return;
        }

        if ($this->getStatePath(isAbsolute: false)) {
            foreach ($this->getStateToDehydrate() as $key => $value) {
                Arr::set($state, $key, $value);
            }
        }

        foreach ($this->getChildComponentContainers() as $container) {
            if ($container->isHidden()) {
                continue;
            }

            $container->dehydrateState($state, $isDehydrated);
        }
    }

    public function dehydrateStateUsing(?Closure $callback): static
    {
        $this->dehydrateStateUsing = $callback;

        return $this;
    }

    /**
     * @param  array<string, mixed> | null  $hydratedDefaultState
     */
    public function hydrateState(?array &$hydratedDefaultState, bool $andCallHydrationHooks = true): void
    {
        $this->hydrateDefaultState($hydratedDefaultState);

        foreach ($this->getChildComponentContainers(withHidden: true) as $container) {
            $container->hydrateState($hydratedDefaultState, $andCallHydrationHooks);
        }

        if ($andCallHydrationHooks) {
            $this->callAfterStateHydrated();
        }
    }

    public function fill(): void
    {
        $defaults = [];

        $this->hydrateDefaultState($defaults);
    }

    /**
     * @param  array<string, mixed> | null  $hydratedDefaultState
     */
    public function hydrateDefaultState(?array &$hydratedDefaultState): void
    {
        if ($hydratedDefaultState === null) {
            $this->loadStateFromRelationships();

            $state = $this->getState();

            // Hydrate all arrayable state objects as arrays by converting
            // them to collections, then using `toArray()`.
            if (is_array($state) || $state instanceof Arrayable) {
                $this->state(collect($state)->toArray());
            }

            return;
        }

        $statePath = $this->getStatePath();

        if (Arr::has($hydratedDefaultState, $statePath)) {
            return;
        }

        if (! $this->hasDefaultState()) {
            $this->state(null);

            return;
        }

        $defaultState = $this->getDefaultState();

        $this->state($defaultState);

        Arr::set($hydratedDefaultState, $statePath, $defaultState);
    }

    public function fillStateWithNull(): void
    {
        if (! Arr::has((array) $this->getLivewire(), $this->getStatePath())) {
            $this->state(null);
        }

        foreach ($this->getChildComponentContainers(withHidden: true) as $container) {
            $container->fillStateWithNull();
        }
    }

    public function mutateDehydratedState(mixed $state): mixed
    {
        $state = $this->stripCharactersFromState($state);

        if (! $this->mutateDehydratedStateUsing) {
            return $state;
        }

        return $this->evaluate(
            $this->mutateDehydratedStateUsing,
            ['state' => $state],
        );
    }

    public function mutateStateForValidation(mixed $state): mixed
    {
        $state = $this->stripCharactersFromState($state);

        if (! $this->mutateStateForValidationUsing) {
            return $state;
        }

        return $this->evaluate(
            $this->mutateStateForValidationUsing,
            ['state' => $state],
        );
    }

    protected function stripCharactersFromState(mixed $state): mixed
    {
        if (! is_string($state)) {
            return $state;
        }

        $stripCharacters = $this->getStripCharacters();

        if (empty($stripCharacters)) {
            return $state;
        }

        return str_replace($stripCharacters, '', $state);
    }

    public function mutatesDehydratedState(): bool
    {
        return ($this->mutateDehydratedStateUsing instanceof Closure) || $this->hasStripCharacters();
    }

    public function mutatesStateForValidation(): bool
    {
        return ($this->mutateStateForValidationUsing instanceof Closure) || $this->hasStripCharacters();
    }

    public function hasStripCharacters(): bool
    {
        return filled($this->getStripCharacters());
    }

    public function mutateDehydratedStateUsing(?Closure $callback): static
    {
        $this->mutateDehydratedStateUsing = $callback;

        return $this;
    }

    public function mutateStateForValidationUsing(?Closure $callback): static
    {
        $this->mutateStateForValidationUsing = $callback;

        return $this;
    }

    public function state(mixed $state): static
    {
        $livewire = $this->getLivewire();

        data_set($livewire, $this->getStatePath(), $this->evaluate($state));

        return $this;
    }

    public function statePath(?string $path): static
    {
        $this->statePath = $path;

        return $this;
    }

    public function getDefaultState(): mixed
    {
        return $this->evaluate($this->defaultState);
    }

    public function getState(): mixed
    {
        $state = data_get($this->getLivewire(), $this->getStatePath());

        if (is_array($state)) {
            return $state;
        }

        if (blank($state)) {
            return null;
        }

        return $state;
    }

    public function getOldState(): mixed
    {
        if (! Livewire::isLivewireRequest()) {
            return null;
        }

        $state = $this->getLivewire()->getOldFormState($this->getStatePath());

        if (blank($state)) {
            return null;
        }

        return $state;
    }

    public function getStatePath(bool $isAbsolute = true): string
    {
        if (! $isAbsolute) {
            return $this->statePath ?? '';
        }

        if (isset($this->cachedAbsoluteStatePath)) {
            return $this->cachedAbsoluteStatePath;
        }

        $pathComponents = [];

        if ($containerStatePath = $this->getContainer()->getStatePath()) {
            $pathComponents[] = $containerStatePath;
        }

        if ($this->hasStatePath()) {
            $pathComponents[] = $this->statePath;
        }

        return $this->cachedAbsoluteStatePath = implode('.', $pathComponents);
    }

    public function hasStatePath(): bool
    {
        return filled($this->statePath);
    }

    protected function hasDefaultState(): bool
    {
        return $this->hasDefaultState;
    }

    public function isDehydrated(): bool
    {
        return (bool) $this->evaluate($this->isDehydrated);
    }

    public function isDehydratedWhenHidden(): bool
    {
        return (bool) $this->evaluate($this->isDehydratedWhenHidden);
    }

    public function isHiddenAndNotDehydrated(): bool
    {
        if (! $this->isHidden()) {
            return false;
        }

        return ! $this->isDehydratedWhenHidden();
    }

    public function getGetCallback(): Get
    {
        return new Get($this);
    }

    public function getSetCallback(): Set
    {
        return new Set($this);
    }

    public function generateRelativeStatePath(string | Component $path, bool $isAbsolute = false): string
    {
        if ($path instanceof Component) {
            return $path->getStatePath();
        }

        if ($isAbsolute) {
            return $path;
        }

        $containerPath = $this->getContainer()->getStatePath();

        while (str($path)->startsWith('../')) {
            $containerPath = Str::contains($containerPath, '.') ?
                (string) str($containerPath)->beforeLast('.') :
                null;

            $path = (string) str($path)->after('../');
        }

        if (blank($containerPath)) {
            return $path;
        }

        return "{$containerPath}.{$path}";
    }

    protected function flushCachedAbsoluteStatePath(): void
    {
        unset($this->cachedAbsoluteStatePath);
    }

    /**
     * @param  string | array<string> | Closure | null  $characters
     */
    public function stripCharacters(string | array | Closure | null $characters): static
    {
        $this->stripCharacters = $characters;

        return $this;
    }

    /**
     * @return array<string>
     */
    public function getStripCharacters(): array
    {
        return $this->cachedStripCharacters ??= Arr::wrap($this->evaluate($this->stripCharacters));
    }
}