<?php

namespace App\Services\Care;

use App\Models\Branch;
use App\Models\Member;
use App\Models\Organization;
use Illuminate\Http\Request;
use Illuminate\Support\Collection;

/**
 * Resolves which Care branch the current user is working in.
 *
 * Staff with a member.branch_id stay locked to that site. Hospital admins (and
 * similar all-branch roles) pick a branch via the queue filters; that choice is
 * remembered in session so Patient / Pharmacy / Lab / Billing queues stay aligned.
 */
class BranchContext
{
    public const SESSION_KEY = 'care.preferred_branch_id';

    public function __construct(
        protected OrganizationResolver $organizations,
    ) {}

    public function canSwitch(?Member $member): bool
    {
        return $this->organizations->branchScope($member) === null;
    }

    /**
     * Active branches the member may see (one site for scoped staff, all for admins).
     *
     * @return Collection<int, Branch>
     */
    public function branches(Request $request, Organization $organization, ?Member $member): Collection
    {
        $scope = $this->organizations->branchScope($member);

        return Branch::owned((string) $request->user()->public_id)
            ->where('organization_id', $organization->id)
            ->where('is_active', true)
            ->when($scope, fn ($q) => $q->where('id', $scope))
            ->orderBy('name')
            ->get();
    }

    /**
     * Preferred working branch id (0 when the org has no active branches).
     * Persists admin selections from ?branch_id= into the session.
     */
    public function resolve(Request $request, Organization $organization, ?Member $member): int
    {
        $branches = $this->branches($request, $organization, $member);
        $allowed = $branches->pluck('id')->map(fn ($id) => (int) $id)->all();
        if ($allowed === []) {
            return 0;
        }

        $scope = $this->organizations->branchScope($member);
        if ($scope !== null) {
            return (int) $scope;
        }

        if ($request->filled('branch_id')) {
            $requested = (int) $request->input('branch_id');
            if (in_array($requested, $allowed, true)) {
                $request->session()->put(self::SESSION_KEY, $requested);

                return $requested;
            }
        }

        $preferred = (int) $request->session()->get(self::SESSION_KEY, 0);
        if ($preferred > 0 && in_array($preferred, $allowed, true)) {
            return $preferred;
        }

        $fallback = (int) $branches->first()->id;
        $request->session()->put(self::SESSION_KEY, $fallback);

        return $fallback;
    }
}