invoiceninja/app/models/Invoice.php

<?php

class Invoice extends EntityModel
{
    public function account()
    {
        return $this->belongsTo('Account');
    }

    public function user()
    {
        return $this->belongsTo('User');
    }

    public function client()
    {
        return $this->belongsTo('Client')->withTrashed();
    }

    public function invoice_items()
    {
        return $this->hasMany('InvoiceItem')->orderBy('id');
    }

    public function invoice_status()
    {
        return $this->belongsTo('InvoiceStatus');
    }

    public function invoice_design()
    {
        return $this->belongsTo('InvoiceDesign');
    }

    public function invitations()
    {
        return $this->hasMany('Invitation')->orderBy('invitations.contact_id');
    }

    public function getName()
    {
        return $this->invoice_number;
    }

    public function getLink()
    {
        return link_to('invoices/'.$this->public_id, $this->invoice_number);
    }

    public function getEntityType()
    {
        return $this->is_quote ? ENTITY_QUOTE : ENTITY_INVOICE;
    }

    public function isSent()
    {
        return $this->invoice_status_id >= INVOICE_STATUS_SENT;
    }

    public function isViewed()
    {
        return $this->invoice_status_id >= INVOICE_STATUS_VIEWED;
    }

    public function isPaid()
    {
        return $this->invoice_status_id >= INVOICE_STATUS_PAID;
    }

    public function hidePrivateFields()
    {
        $this->setVisible([
            'invoice_number',
            'discount',
            'is_amount_discount',
            'po_number',
            'invoice_date',
            'due_date',
            'terms',
            'invoice_footer',
            'public_notes',
            'amount',
            'balance',
            'invoice_items',
            'client',
            'tax_name',
            'tax_rate',
            'account',
            'invoice_design',
            'invoice_design_id',
            'is_pro',
            'is_quote',
            'custom_value1',
            'custom_value2',
            'custom_taxes1',
            'custom_taxes2',
        ]);

        $this->client->setVisible([
            'name',
            'id_number',
            'vat_number',
            'address1',
            'address2',
            'city',
            'state',
            'postal_code',
            'work_phone',
            'payment_terms',
            'contacts',
            'country',
            'currency_id',
            'custom_value1',
            'custom_value2',
        ]);

        $this->account->setVisible([
            'name',
            'id_number',
            'vat_number',
            'address1',
            'address2',
            'city',
            'state',
            'postal_code',
            'work_phone',
            'work_email',
            'country',
            'currency_id',
            'custom_label1',
            'custom_value1',
            'custom_label2',
            'custom_value2',
            'custom_client_label1',
            'custom_client_label2',
            'primary_color',
            'secondary_color',
            'hide_quantity',
            'hide_paid_to_date',
            'custom_invoice_label1',
            'custom_invoice_label2',
            'pdf_email_attachment',
        ]);

        foreach ($this->invoice_items as $invoiceItem) {
            $invoiceItem->setVisible([
                'product_key',
                'notes',
                'cost',
                'qty',
                'tax_name',
                'tax_rate',
            ]);
        }

        foreach ($this->client->contacts as $contact) {
            $contact->setVisible([
                'first_name',
                'last_name',
                'email',
                'phone',
            ]);
        }

        return $this;
    }

    public function shouldSendToday()
    {
        if (!$this->start_date || strtotime($this->start_date) > strtotime('now')) {
            return false;
        }

        if ($this->end_date && strtotime($this->end_date) < strtotime('now')) {
            return false;
        }

        $dayOfWeekToday = date('w');
        $dayOfWeekStart = date('w', strtotime($this->start_date));

        $dayOfMonthToday = date('j');
        $dayOfMonthStart = date('j', strtotime($this->start_date));

        if (!$this->last_sent_date) {
            return true;
        } else {
            $date1 = new DateTime($this->last_sent_date);
            $date2 = new DateTime();
            $diff = $date2->diff($date1);
            $daysSinceLastSent = $diff->format("%a");
            $monthsSinceLastSent = ($diff->format('%y') * 12) + $diff->format('%m');

            if ($daysSinceLastSent == 0) {
                return false;
            }
        }

        switch ($this->frequency_id) {
            case FREQUENCY_WEEKLY:
                return $daysSinceLastSent >= 7;
            case FREQUENCY_TWO_WEEKS:
                return $daysSinceLastSent >= 14;
            case FREQUENCY_FOUR_WEEKS:
                return $daysSinceLastSent >= 28;
            case FREQUENCY_MONTHLY:
                return $monthsSinceLastSent >= 1;
            case FREQUENCY_THREE_MONTHS:
                return $monthsSinceLastSent >= 3;
            case FREQUENCY_SIX_MONTHS:
                return $monthsSinceLastSent >= 6;
            case FREQUENCY_ANNUALLY:
                return $monthsSinceLastSent >= 12;
            default:
                return false;
        }

        return false;
    }
}

Invoice::created(function ($invoice) {
    $invoice->account->incrementCounter($invoice->invoice_number, $invoice->is_quote, $invoice->recurring_invoice_id);
    Activity::createInvoice($invoice);
});

Invoice::updating(function ($invoice) {
    Activity::updateInvoice($invoice);
});

Invoice::deleting(function ($invoice) {
    Activity::archiveInvoice($invoice);
});

Invoice::restoring(function ($invoice) {
    Activity::restoreInvoice($invoice);
});