<?php

namespace Modules\MaterialLogistics\Services;

use Modules\MaterialLogistics\Enums\DeploymentStatus;
use Modules\MaterialLogistics\Events\MaterialDelivered;
use Modules\MaterialLogistics\Events\MaterialRequested;
use Modules\MasterData\Models\Material;
use Modules\MaterialLogistics\Models\MaterialDeployment;
use Modules\MaterialLogistics\Models\ProjectInventory;

class InventoryService
{
    /**
     * Allocate stock to a project (add to on_hand).
     */
    public function allocate(int $projectId, int $materialId, float $quantity, ?float $unitCost = null): ProjectInventory
    {
        $material = Material::findOrFail($materialId);

        return ProjectInventory::updateOrCreate(
            ['project_id' => $projectId, 'material_id' => $materialId],
            [
                'on_hand_qty' => \DB::raw("on_hand_qty + {$quantity}"),
                'unit_cost' => $unitCost ?? $material->unit_cost,
            ]
        );
    }

    /**
     * Request a deployment (creates deployment record).
     */
    public function requestDeployment(
        int $projectId,
        int $materialId,
        float $quantity,
        ?int $requestedBy = null,
        ?string $notes = null,
    ): MaterialDeployment {
        $deployment = MaterialDeployment::create([
            'project_id' => $projectId,
            'material_id' => $materialId,
            'requested_by' => $requestedBy,
            'quantity' => $quantity,
            'status' => DeploymentStatus::Requested,
            'notes' => $notes,
        ]);

        MaterialRequested::dispatch($deployment);

        return $deployment;
    }

    /**
     * Dispatch deployment (guard: check inventory).
     */
    public function dispatch(MaterialDeployment $deployment): MaterialDeployment
    {
        $inventory = ProjectInventory::where('project_id', $deployment->project_id)
            ->where('material_id', $deployment->material_id)
            ->first();

        if (!$inventory || $inventory->available_qty < $deployment->quantity) {
            throw new \InvalidArgumentException(
                "Insufficient stock. Available: " . ($inventory?->available_qty ?? 0) . ", Requested: {$deployment->quantity}"
            );
        }

        // Allocate from inventory
        $inventory->increment('allocated_qty', $deployment->quantity);

        $deployment->transitionTo(DeploymentStatus::PendingDispatch);
        $deployment->transitionTo(DeploymentStatus::InTransit);

        return $deployment->fresh();
    }

    /**
     * Mark as delivered.
     */
    public function deliver(MaterialDeployment $deployment): MaterialDeployment
    {
        $deployment->transitionTo(DeploymentStatus::Delivered);
        MaterialDelivered::dispatch($deployment);
        return $deployment->fresh();
    }

    /**
     * Mark as consumed (deduct from inventory).
     */
    public function consume(MaterialDeployment $deployment): MaterialDeployment
    {
        $deployment->transitionTo(DeploymentStatus::Consumed);

        $inventory = ProjectInventory::where('project_id', $deployment->project_id)
            ->where('material_id', $deployment->material_id)
            ->first();

        if ($inventory) {
            $inventory->decrement('on_hand_qty', $deployment->quantity);
            $inventory->decrement('allocated_qty', $deployment->quantity);
            $inventory->increment('consumed_qty', $deployment->quantity);
        }

        return $deployment->fresh();
    }

    /**
     * Cancel a deployment.
     */
    public function cancel(MaterialDeployment $deployment): MaterialDeployment
    {
        // Release allocated stock if it was dispatched
        if (in_array($deployment->status, [DeploymentStatus::PendingDispatch, DeploymentStatus::InTransit])) {
            $inventory = ProjectInventory::where('project_id', $deployment->project_id)
                ->where('material_id', $deployment->material_id)
                ->first();

            if ($inventory) {
                $inventory->decrement('allocated_qty', $deployment->quantity);
            }
        }

        $deployment->transitionTo(DeploymentStatus::Cancelled);
        return $deployment->fresh();
    }
}