<?php

namespace App\Traits;

use App\Models\User;

/**
 * Trait for models with multi-tier approval workflows.
 *
 * Usage:
 * 1. Add `use HasApprovalWorkflow;` to your model
 * 2. Define STATUS_* constants for each approval stage
 * 3. Define STATUS_REJECTED constant
 * 4. Override methods as needed for custom approval logic
 */
trait HasApprovalWorkflow
{
    /**
     * Check if document/payment is rejected
     */
    public function isRejected(): bool
    {
        return $this->status === static::STATUS_REJECTED;
    }

    /**
     * Check if document/payment is pending (initial state)
     */
    public function isPending(): bool
    {
        return $this->status === static::STATUS_PENDING;
    }

    /**
     * Check if self-approval is being attempted
     * Prevents users from approving their own submissions
     *
     * @param User|null $user The user attempting to approve
     * @param string $submitterField The field containing the submitter's user ID
     */
    protected function isSelfApproval(?User $user, string $submitterField = 'submitted_by_user_id'): bool
    {
        if (! $user) {
            return false;
        }

        $submitterId = $this->{$submitterField};

        return $submitterId && $submitterId === $user->id;
    }

    /**
     * Get the human-readable status label
     * Override in model for custom labels
     */
    public function getStatusLabelAttribute(): string
    {
        return ucfirst(str_replace('_', ' ', $this->status));
    }

    /**
     * Check if approval can proceed based on current status
     *
     * @param string $requiredStatus The status required before this approval
     * @param User|null $user The user attempting to approve
     * @param bool $checkSelfApproval Whether to check for self-approval
     */
    protected function canProceedWithApproval(
        string $requiredStatus,
        ?User $user = null,
        bool $checkSelfApproval = true
    ): bool {
        if ($this->status !== $requiredStatus) {
            return false;
        }

        if ($checkSelfApproval && $this->isSelfApproval($user)) {
            return false;
        }

        return true;
    }

    /**
     * Get the rejection details
     */
    public function getRejectionDetails(): ?array
    {
        if (! $this->isRejected()) {
            return null;
        }

        return [
            'reason' => $this->rejection_reason ?? null,
            'rejected_by' => $this->rejectedBy ?? null,
            'rejected_at' => $this->rejected_at ?? null,
        ];
    }

    /**
     * Check if model can be rejected
     * Default: can reject if not already rejected
     */
    public function canBeRejected(): bool
    {
        return ! $this->isRejected();
    }

    /**
     * Get the next approver role required
     * Override in model to implement specific logic
     */
    public function getNextApproverRole(): ?string
    {
        return null;
    }

    /**
     * Get approval history
     * Returns array of approval stages that have been completed
     */
    public function getApprovalHistory(): array
    {
        $history = [];

        // This should be overridden in each model to provide specific fields
        // Example structure:
        // [
        //     ['stage' => 'cashier', 'user' => User, 'at' => Carbon],
        //     ['stage' => 'accountant', 'user' => User, 'at' => Carbon],
        // ]

        return $history;
    }
}