<?php

namespace Modules\IndustrialEngineering\Services;

use Illuminate\Support\Facades\DB;
use InvalidArgumentException;
use Modules\IndustrialEngineering\Models\Bom;
use Modules\IndustrialEngineering\Models\BomLine;
use Modules\IndustrialEngineering\Models\BomStructureTemplate;

class BomTemplateService
{
    public function __construct(
        protected BomTreeService $bomTreeService
    ) {
    }

    /**
     * Built-in structure presets (no DB row required).
     */
    public function builtinPresets(): array
    {
        return [
            'air_section_full' => [
                'key' => 'air_section_full',
                'name' => __('industrialengineering::lang.preset_air_section_full'),
                'description' => __('industrialengineering::lang.preset_air_section_full_desc'),
                'category' => 'air',
                'nodes' => [
                    [
                        'name' => __('industrialengineering::lang.preset_air_section_name'),
                        'item_type' => 'assembly',
                        'position_code' => 'M01-AIR',
                        'quantity' => 1,
                        'children' => [
                            [
                                'name' => __('industrialengineering::lang.preset_pump_name'),
                                'item_type' => 'subassembly',
                                'position_code' => 'M01-PMP',
                                'quantity' => 1,
                                'children' => [
                                    ['name' => __('industrialengineering::lang.preset_motor_electric'), 'item_type' => 'part', 'quantity' => 1],
                                    ['name' => __('industrialengineering::lang.preset_motor_gas'), 'item_type' => 'part', 'quantity' => 1],
                                    ['name' => __('industrialengineering::lang.preset_pressure_sensor'), 'item_type' => 'part', 'quantity' => 1],
                                    ['name' => __('industrialengineering::lang.preset_check_valve'), 'item_type' => 'part', 'quantity' => 1],
                                ],
                            ],
                            [
                                'name' => __('industrialengineering::lang.preset_dryer_name'),
                                'item_type' => 'subassembly',
                                'position_code' => 'M01-DRY',
                                'quantity' => 1,
                            ],
                            [
                                'name' => __('industrialengineering::lang.preset_tank_name'),
                                'item_type' => 'subassembly',
                                'position_code' => 'M01-TNK',
                                'quantity' => 1,
                            ],
                        ],
                    ],
                ],
            ],
            'air_section_children' => [
                'key' => 'air_section_children',
                'name' => __('industrialengineering::lang.preset_air_children'),
                'description' => __('industrialengineering::lang.preset_air_children_desc'),
                'category' => 'air',
                'nodes' => [
                    [
                        'name' => __('industrialengineering::lang.preset_pump_name'),
                        'item_type' => 'subassembly',
                        'position_code' => 'M01-PMP',
                        'quantity' => 1,
                        'children' => [
                            ['name' => __('industrialengineering::lang.preset_motor_electric'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_motor_gas'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_pressure_sensor'), 'item_type' => 'part', 'quantity' => 1],
                        ],
                    ],
                    [
                        'name' => __('industrialengineering::lang.preset_dryer_name'),
                        'item_type' => 'subassembly',
                        'position_code' => 'M01-DRY',
                        'quantity' => 1,
                    ],
                    [
                        'name' => __('industrialengineering::lang.preset_tank_name'),
                        'item_type' => 'subassembly',
                        'position_code' => 'M01-TNK',
                        'quantity' => 1,
                    ],
                ],
            ],
            'pump_kit' => [
                'key' => 'pump_kit',
                'name' => __('industrialengineering::lang.preset_pump_kit'),
                'description' => __('industrialengineering::lang.preset_pump_kit_desc'),
                'category' => 'pump',
                'nodes' => [
                    ['name' => __('industrialengineering::lang.preset_motor_electric'), 'item_type' => 'part', 'quantity' => 1],
                    ['name' => __('industrialengineering::lang.preset_motor_gas'), 'item_type' => 'part', 'quantity' => 1],
                    ['name' => __('industrialengineering::lang.preset_pressure_sensor'), 'item_type' => 'part', 'quantity' => 1],
                    ['name' => __('industrialengineering::lang.preset_check_valve'), 'item_type' => 'part', 'quantity' => 1],
                ],
            ],
            'compressor_station_20' => [
                'key' => 'compressor_station_20',
                'name' => __('industrialengineering::lang.preset_compressor_station_20'),
                'description' => __('industrialengineering::lang.preset_compressor_station_20_desc'),
                'category' => 'air',
                'nodes' => [
                    [
                        'name' => __('industrialengineering::lang.preset_air_pump'),
                        'item_type' => 'device',
                        'position_code' => 'DEV-PMP',
                        'quantity' => 1,
                        'children' => [
                            ['name' => __('industrialengineering::lang.preset_motor_55kw'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_pump_impeller'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_air_filter'), 'item_type' => 'consumable', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_mechanical_seal'), 'item_type' => 'consumable', 'quantity' => 1],
                        ],
                    ],
                    [
                        'name' => __('industrialengineering::lang.preset_industrial_vacuum'),
                        'item_type' => 'device',
                        'position_code' => 'DEV-VAC',
                        'quantity' => 1,
                        'children' => [
                            ['name' => __('industrialengineering::lang.preset_vacuum_pump'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_inlet_filter'), 'item_type' => 'consumable', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_solenoid_valve'), 'item_type' => 'part', 'quantity' => 1],
                        ],
                    ],
                    [
                        'name' => __('industrialengineering::lang.preset_piston_compressor'),
                        'item_type' => 'device',
                        'position_code' => 'DEV-PST',
                        'quantity' => 1,
                        'children' => [
                            ['name' => __('industrialengineering::lang.preset_cylinder'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_connecting_pipe'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_oil_filter'), 'item_type' => 'consumable', 'quantity' => 1],
                        ],
                    ],
                    [
                        'name' => __('industrialengineering::lang.preset_screw_compressor'),
                        'item_type' => 'device',
                        'position_code' => 'DEV-SCR',
                        'quantity' => 1,
                        'children' => [
                            ['name' => __('industrialengineering::lang.preset_rotor'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_separator'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_oil_filter'), 'item_type' => 'consumable', 'quantity' => 1],
                        ],
                    ],
                    [
                        'name' => __('industrialengineering::lang.preset_dryer_assembly'),
                        'item_type' => 'assembly',
                        'position_code' => 'ASM-DRY',
                        'quantity' => 1,
                        'children' => [
                            ['name' => __('industrialengineering::lang.preset_refrigerant_dryer'), 'item_type' => 'part', 'quantity' => 1],
                            ['name' => __('industrialengineering::lang.preset_condensate_drain'), 'item_type' => 'part', 'quantity' => 1],
                        ],
                    ],
                ],
            ],
        ];
    }

    public function listForBusiness(int $businessId): array
    {
        $builtins = array_values($this->builtinPresets());

        $saved = BomStructureTemplate::forBusiness($businessId)
            ->where('is_system', false)
            ->orderByDesc('updated_at')
            ->get()
            ->map(fn (BomStructureTemplate $t) => [
                'id' => $t->id,
                'key' => 'saved:'.$t->id,
                'name' => $t->name,
                'description' => $t->description,
                'category' => $t->category,
                'is_saved' => true,
                'updated_at' => $t->updated_at?->toDateTimeString(),
            ])
            ->all();

        return [
            'builtin' => $builtins,
            'saved' => $saved,
        ];
    }

    /**
     * Apply preset key or saved template id under a parent BOM line.
     *
     * @return array{created_count:int, lines:array<int, BomLine>}
     */
    public function apply(Bom $bom, ?int $parentLineId, string $templateKey): array
    {
        $nodes = $this->resolveTemplateNodes($bom->business_id, $templateKey);

        return $this->bulkAddNodes($bom, $parentLineId, $nodes);
    }

    /**
     * Recursively add multiple nodes under a parent.
     *
     * @param  array<int, array<string, mixed>>  $nodes
     * @return array{created_count:int, lines:array<int, BomLine>}
     */
    public function bulkAddNodes(Bom $bom, ?int $parentLineId, array $nodes): array
    {
        return DB::transaction(function () use ($bom, $parentLineId, $nodes) {
            $created = [];
            foreach ($nodes as $nodeDef) {
                $created = array_merge($created, $this->addNodeRecursive($bom, $parentLineId, $nodeDef));
            }

            return [
                'created_count' => count($created),
                'lines' => $created,
            ];
        });
    }

    public function saveFromBomLine(BomLine $line, string $name, ?string $description = null, ?string $category = 'custom'): BomStructureTemplate
    {
        $structure = $this->exportLineSubtree($line);

        return BomStructureTemplate::create([
            'business_id' => $line->business_id,
            'name' => $name,
            'description' => $description,
            'category' => $category ?: 'custom',
            'structure_json' => ['nodes' => [$structure]],
            'is_system' => false,
            'created_by' => auth()->id(),
        ]);
    }

    /**
     * Export a BOM line and its descendants to a portable node definition.
     */
    public function exportLineSubtree(BomLine $line): array
    {
        $line->loadMissing(['itemMaster', 'children.itemMaster']);

        $item = $line->itemMaster;

        $def = [
            'name' => $item?->name,
            'item_type' => $item?->item_type ?? 'part',
            'item_code' => $item?->item_code,
            'quantity' => (float) $line->quantity,
            'position_code' => $line->position_code,
            'find_number' => $line->find_number,
        ];

        if ($line->children->isNotEmpty()) {
            $def['children'] = $line->children
                ->sortBy('sort_order')
                ->map(fn (BomLine $child) => $this->exportLineSubtree($child))
                ->values()
                ->all();
        }

        return $def;
    }

    protected function resolveTemplateNodes(int $businessId, string $templateKey): array
    {
        if (str_starts_with($templateKey, 'saved:')) {
            $id = (int) substr($templateKey, 6);
            $template = BomStructureTemplate::forBusiness($businessId)->findOrFail($id);
            $json = $template->structure_json ?? [];

            return $json['nodes'] ?? (is_array($json) && isset($json[0]) ? $json : []);
        }

        $presets = $this->builtinPresets();
        if (! isset($presets[$templateKey])) {
            throw new InvalidArgumentException(__('industrialengineering::lang.template_not_found'));
        }

        return $presets[$templateKey]['nodes'] ?? [];
    }

    /**
     * @return array<int, BomLine>
     */
    protected function addNodeRecursive(Bom $bom, ?int $parentLineId, array $nodeDef): array
    {
        $children = $nodeDef['children'] ?? [];
        unset($nodeDef['children']);

        $line = $this->bomTreeService->addNode($bom, $parentLineId, $nodeDef);
        $created = [$line];

        foreach ($children as $childDef) {
            $created = array_merge($created, $this->addNodeRecursive($bom, $line->id, $childDef));
        }

        return $created;
    }
}