<?php

namespace Modules\Core\Shipping\Extensions;

use Filament\Schemas\Schema;
use Filament\Schemas\Components\Component;
use Filament\Schemas\Components\Concerns\HasChildComponents;
use Filament\Schemas\Components\Utilities\Get;
use InvalidArgumentException;
use Filament\Forms\Components\Select;
use Filament\Tables\Columns\TextColumn;
use Filament\Tables\Table;
use Lunar\Admin\Support\Extending\ResourceExtension;
use Lunar\Admin\Support\Forms\Components\TranslatedText;
use Lunar\Shipping\Facades\Shipping;
use Modules\Core\Shipping\Contracts\SupportsLivePricing;
use Modules\Core\Shipping\Support\ShippingMethodName;

class ShippingMethodResourceExtension extends ResourceExtension
{
    public function extendForm(Schema $schema): Schema
    {
        return $schema->components(
            $this->replaceChargeByField(
                $this->replaceNameField(
                    $this->replaceDriverField($schema->getComponents())
                )
            )
        );
    }

    /**
     * Replaces the vendor's plain-string `name` TextInput with
     * Lunar's own TranslatedText — `name` is now a locale-keyed JSON
     * column (see database/migrations/..._make_shipping_methods_name_translatable.php),
     * same shape/resolution as PaymentMethod.name and Product/Collection
     * names (Lunar\Base\Traits\HasTranslations).
     */
    private function replaceNameField(array $components): array
    {
        return array_map(function (Component $component) {
            if (method_exists($component, 'getName') && $component->getName() === 'name') {
                return self::translatedNameField();
            }

            if (in_array(HasChildComponents::class, class_uses_recursive($component), true)) {
                $component->schema($this->replaceNameField($component->getDefaultChildComponents()));
            }

            return $component;
        }, $components);
    }

    /**
     * ShippingMethod.name is a locale-keyed JSON column (see database/
     * migrations/..._make_shipping_methods_name_translatable.php), but
     * ShippingMethod is a vendor Eloquent model with no cast declared for
     * it — Lunar\Shipping\Models\ShippingMethod only casts `data`, and
     * there's no ModelManifest contract wired up to swap in a first-party
     * subclass that adds one (Contracts\ShippingMethod exists but is
     * never bound — see this class's own git history/nameColumn() for
     * the same gap on the read side). TranslatedText itself round-trips
     * plain array state, so afterStateHydrated()/dehydrateStateUsing()
     * decode/encode the raw JSON string at the field boundary instead —
     * the model attribute is a string on the way in and out, only ever
     * an array while Filament's schema state holds it.
     */
    /**
     * Also called directly by Modules\Core\Shipping\Extensions\
     * ShippingMethodListExtension — the create action's form is built
     * inline by the vendor's ListShippingMethod page rather than through
     * this class's own extendForm() pipeline, so it needs the same
     * translated field wired in separately.
     */
    public static function translatedNameField(): TranslatedText
    {
        $field = TranslatedText::make('name')
            ->label('Name')
            ->required()
            ->afterStateHydrated(function (TranslatedText $component, $state) {
                // On create there is no record yet, so Filament hydrates
                // this from the field's own default/current state — already
                // an array (or null), never the raw JSON string edit gets
                // from the model attribute. Only decode when it's a string.
                if (is_string($state)) {
                    $state = json_decode($state, true);
                }

                $component->state(is_array($state) ? $state : []);
            })
            ->dehydrateStateUsing(fn ($state) => json_encode(is_array($state) ? $state : []));

        $field->expanded = true;

        return $field;
    }

    /**
     * Extend the vendor's cart_total/weight charge_by Select with a third
     * "live" option — only offered when the currently selected driver
     * supports live pricing (see SupportsLivePricing). Picking it is what
     * tells the driver to call its carrier API instead of resolving a
     * price break.
     */
    private function replaceChargeByField(array $components): array
    {
        return array_map(function (Component $component) {
            if (method_exists($component, 'getName') && $component->getName() === 'charge_by') {
                return $this->chargeBySelect();
            }

            if (in_array(HasChildComponents::class, class_uses_recursive($component), true)) {
                $component->schema(
                    $this->replaceChargeByField($component->getDefaultChildComponents())
                );
            }

            return $component;
        }, $components);
    }

    private function chargeBySelect(): Select
    {
        return Select::make('charge_by')
            ->label('Charge by')
            ->options(function (Get $get) {
                $options = [
                    'cart_total' => 'Cart Total',
                    'weight' => 'Weight',
                ];

                // "charge_by" is nested inside a Group with
                // ->statePath('data'), while "driver" sits one level up, at
                // the form root. Note: an *absolute* path here would need to
                // additionally account for the page's own form wrapper
                // (EditRecord::getFormStatePath() === 'data'), which relative
                // paths never cross — so "../driver" (relative) is the
                // correct, page-independent way to reach it, not an
                // absolute 'driver' string.
                if ($this->driverSupportsLivePricing($get('../driver'))) {
                    $options['live'] = 'Live API pricing';
                }

                return $options;
            })
            ->live();
    }

    private function driverSupportsLivePricing(?string $driver): bool
    {
        if (! $driver) {
            return false;
        }

        try {
            return Shipping::driver($driver) instanceof SupportsLivePricing;
        } catch (InvalidArgumentException) {
            return false;
        }
    }

    public function extendTable(Table $table): Table
    {
        return $table->columns(
            array_map(function ($column) {
                if (method_exists($column, 'getName') && $column->getName() === 'driver') {
                    return $this->driverColumn();
                }

                if (method_exists($column, 'getName') && $column->getName() === 'name') {
                    return $this->nameColumn();
                }

                return $column;
            }, $table->getColumns())
        );
    }

    private function driverColumn(): TextColumn
    {
        return TextColumn::make('driver')
            ->label('Type')
            ->formatStateUsing(fn ($state) => $this->driverLabel($state));
    }

    /**
     * `name` is a locale-keyed JSON column (see Modules\Core\Shipping\
     * Support\ShippingMethodName's own docblock for why it needs manual
     * decoding rather than a model cast). Uses ->state() rather than
     * ->formatStateUsing(), which would otherwise have Filament iterate a
     * would-be array state as a multi-value list (one formatted cell per
     * locale) instead of a single string.
     */
    private function nameColumn(): TextColumn
    {
        return TextColumn::make('name')
            ->label('Name')
            ->state(fn ($record) => ShippingMethodName::resolve($record));
    }

    private function driverLabel(string $key): string
    {
        $driver = collect(Shipping::getSupportedDrivers())->get($key);

        return $driver?->name() ?? $key;
    }

    /**
     * Recursively walk the form tree and replace the hardcoded driver
     * Select (nested inside Section > Group) with one listing every
     * registered driver, built-in or custom.
     *
     * @param array<Component> $components
     * @return array<Component>
     */
    private function replaceDriverField(array $components): array
    {
        return array_map(function (Component $component) {
            if (method_exists($component, 'getName') && $component->getName() === 'driver') {
                return $this->driverSelect();
            }

            if (in_array(HasChildComponents::class, class_uses_recursive($component), true)) {
                $component->schema(
                    $this->replaceDriverField($component->getDefaultChildComponents())
                );
            }

            return $component;
        }, $components);
    }

    private function driverSelect(): Select
    {
        return Select::make('driver')
            ->label('Type')
            ->options(fn () => collect(Shipping::getSupportedDrivers())
                ->mapWithKeys(fn ($driver, $key) => [$key => $driver->name()]))
            ->default('acs')
            ->live();
    }
}