PyInvoice/pyinvoice/templates.py

from __future__ import unicode_literals
from datetime import datetime, date
from decimal import Decimal

from reportlab.lib import colors
from reportlab.lib.enums import TA_CENTER, TA_RIGHT
from reportlab.lib.pagesizes import letter
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.units import inch
from reportlab.platypus import SimpleDocTemplate, Paragraph, Table, Spacer

from pyinvoice.components import SimpleTable, TableWithHeader, PaidStamp
from pyinvoice.models import PDFInfo, Item, Transaction, InvoiceInfo, ServiceProviderInfo, ClientInfo


class SimpleInvoice(SimpleDocTemplate):
    default_pdf_info = PDFInfo(title='Invoice', author='CiCiApp.com', subject='Invoice')

    def __init__(self, invoice_path, pdf_info=None):
        if not pdf_info:
            pdf_info = self.default_pdf_info

        SimpleDocTemplate.__init__(
            self,
            invoice_path,
            pagesize=letter,
            rightMargin=inch,
            leftMargin=inch,
            topMargin=inch,
            bottomMargin=inch,
            **pdf_info.__dict__
        )

        self._defined_styles = getSampleStyleSheet()
        self._defined_styles.add(
            ParagraphStyle('RightHeading1', parent=self._defined_styles.get('Heading1'), alignment=TA_RIGHT)
        )
        self._defined_styles.add(
            ParagraphStyle('TableParagraph', parent=self._defined_styles.get('Normal'), alignment=TA_CENTER)
        )

        self.invoice_info = None
        self.service_provider_info = None
        self.client_info = None
        self.is_paid = False
        self._items = []
        self._item_tax_rate = None
        self._transactions = []
        self._story = []
        self._bottom_tip = None
        self._bottom_tip_align = None

    @property
    def items(self):
        return self._items[:]

    def add_item(self, item):
        if isinstance(item, Item):
            self._items.append(item)

    def set_item_tax_rate(self, rate):
        self._item_tax_rate = rate

    @property
    def transactions(self):
        return self._transactions[:]

    def add_transaction(self, t):
        if isinstance(t, Transaction):
            self._transactions.append(t)

    def set_bottom_tip(self, text, align=TA_CENTER):
        self._bottom_tip = text
        self._bottom_tip_align = align

    @staticmethod
    def _format_value(value):
        if isinstance(value, datetime):
            value = value.strftime('%Y-%m-%d %H:%M')
        elif isinstance(value, date):
            value = value.strftime('%Y-%m-%d')
        return value

    def _attribute_to_table_data(self, instance, attribute_verbose_name_list):
        data = []

        for property_name, verbose_name in attribute_verbose_name_list:
            attr = getattr(instance, property_name)
            if attr:
                attr = self._format_value(attr)
                data.append(['{0}:'.format(verbose_name), attr])

        return data

    def _invoice_info_data(self):
        if isinstance(self.invoice_info, InvoiceInfo):
            props = [('invoice_id', 'Invoice id'), ('invoice_datetime', 'Invoice date'),
                     ('due_datetime', 'Invoice due date')]

            return self._attribute_to_table_data(self.invoice_info, props)

        return []

    def _build_invoice_info(self):
        invoice_info_data = self._invoice_info_data()
        if invoice_info_data:
            self._story.append(Paragraph('Invoice', self._defined_styles.get('RightHeading1')))
            self._story.append(SimpleTable(invoice_info_data, horizontal_align='RIGHT'))

    def _service_provider_data(self):
        if isinstance(self.service_provider_info, ServiceProviderInfo):
            props = [('name', 'Name'), ('street', 'Street'), ('city', 'City'), ('state', 'State'),
                     ('country', 'Country'), ('post_code', 'Post code'), ('vat_tax_number', 'Vat/Tax number')]

            return self._attribute_to_table_data(self.service_provider_info, props)

        return []

    def _build_service_provider_info(self):
        # Merchant
        service_provider_info_data = self._service_provider_data()
        if service_provider_info_data:
            self._story.append(Paragraph('Merchant', self._defined_styles.get('RightHeading1')))
            self._story.append(SimpleTable(service_provider_info_data, horizontal_align='RIGHT'))

    def _client_info_data(self):
        if not isinstance(self.client_info, ClientInfo):
            return []

        props = [('name', 'Name'), ('street', 'Street'), ('city', 'City'), ('state', 'State'),
                 ('country', 'Country'), ('post_code', 'Post code'), ('email', 'Email'), ('client_id', 'Client id')]
        return self._attribute_to_table_data(self.client_info, props)

    def _build_client_info(self):
        # ClientInfo
        client_info_data = self._client_info_data()
        if client_info_data:
            self._story.append(Paragraph('Client', self._defined_styles.get('Heading1')))
            self._story.append(SimpleTable(client_info_data, horizontal_align='LEFT'))

    def _build_service_provider_and_client_info(self):
        if isinstance(self.service_provider_info, ServiceProviderInfo) and isinstance(self.client_info, ClientInfo):
            # Merge Table
            table_data = [
                [
                    Paragraph('Service Provider', self._defined_styles.get('Heading1')), '',
                    '',
                    Paragraph('Client', self._defined_styles.get('Heading1')), ''
                ]
            ]
            table_style = [
                ('SPAN', (0, 0), (1, 0)),
                ('SPAN', (3, 0), (4, 0)),
                ('LINEBELOW', (0, 0), (1, 0), 1, colors.gray),
                ('LINEBELOW', (3, 0), (4, 0), 1, colors.gray),
                ('LEFTPADDING', (0, 0), (-1, -1), 0),
            ]
            client_info_data = self._client_info_data()
            service_provider_data = self._service_provider_data()
            diff = abs(len(client_info_data) - len(service_provider_data))
            if diff > 0:
                if len(client_info_data) < len(service_provider_data):
                    client_info_data.extend([["", ""]]*diff)
                else:
                    service_provider_data.extend([["", ""]*diff])
            for d in zip(service_provider_data, client_info_data):
                d[0].append('')
                d[0].extend(d[1])
                table_data.append(d[0])
            self._story.append(
                Table(table_data, style=table_style)
            )
        else:
            self._build_service_provider_info()
            self._build_client_info()

    def _item_raw_data_and_subtotal(self):
        item_data = []
        item_subtotal = 0

        for item in self._items:
            if not isinstance(item, Item):
                continue

            item_data.append(
                (
                    item.name,
                    Paragraph(item.description, self._defined_styles.get('TableParagraph')),
                    item.units,
                    item.unit_price,
                    item.amount
                )
            )
            item_subtotal += item.amount

        return item_data, item_subtotal

    def _item_data_and_style(self):
        # Items
        item_data, item_subtotal = self._item_raw_data_and_subtotal()
        style = []

        if not item_data:
            return item_data, style

        self._story.append(
            Paragraph('Detail', self._defined_styles.get('Heading1'))
        )

        item_data_title = ('Name', 'Description', 'Units', 'Unit Price', 'Amount')
        item_data.insert(0, item_data_title)  # Insert title

        # Summary field
        sum_start_y_index = len(item_data)
        sum_end_x_index = -1 - 1
        sum_start_x_index = len(item_data_title) - abs(sum_end_x_index)

        # ##### Subtotal #####
        item_data.append(
            ('Subtotal', '', '', '', item_subtotal)
        )

        style.append(('SPAN', (0, sum_start_y_index), (sum_start_x_index, sum_start_y_index)))
        style.append(('ALIGN', (0, sum_start_y_index), (sum_end_x_index, -1), 'RIGHT'))

        # Tax total
        if self._item_tax_rate is not None:
            tax_total = item_subtotal * (Decimal(str(self._item_tax_rate)) / Decimal('100'))
            item_data.append(
                ('Vat/Tax ({0}%)'.format(self._item_tax_rate), '', '', '', tax_total)
            )
            sum_start_y_index += 1
            style.append(('SPAN', (0, sum_start_y_index), (sum_start_x_index, sum_start_y_index)))
            style.append(('ALIGN', (0, sum_start_y_index), (sum_end_x_index, -1), 'RIGHT'))
        else:
            tax_total = None

        # Total
        total = item_subtotal + (tax_total if tax_total else Decimal('0'))
        item_data.append(('Total', '', '', '', total))
        sum_start_y_index += 1
        style.append(('SPAN', (0, sum_start_y_index), (sum_start_x_index, sum_start_y_index)))
        style.append(('ALIGN', (0, sum_start_y_index), (sum_end_x_index, -1), 'RIGHT'))

        return item_data, style

    def _build_items(self):
        item_data, style = self._item_data_and_style()
        if item_data:
            self._story.append(TableWithHeader(item_data, horizontal_align='LEFT', style=style))

    def _transactions_data(self):
        transaction_table_data = [
            (
                t.transaction_id,
                Paragraph(t.gateway, self._defined_styles.get('TableParagraph')),
                self._format_value(t.transaction_datetime),
                t.amount,
            ) for t in self._transactions if isinstance(t, Transaction)
        ]

        if transaction_table_data:
            transaction_table_data.insert(0, ('Transaction id', 'Gateway', 'Transaction date', 'Amount'))

        return transaction_table_data

    def _build_transactions(self):
        # Transaction
        transaction_table_data = self._transactions_data()

        if transaction_table_data:
            self._story.append(Paragraph('Transaction', self._defined_styles.get('Heading1')))
            self._story.append(TableWithHeader(transaction_table_data, horizontal_align='LEFT'))

    def _build_bottom_tip(self):
        if self._bottom_tip:
            self._story.append(Spacer(5, 5))
            self._story.append(
                Paragraph(
                    self._bottom_tip,
                    ParagraphStyle(
                        'BottomTip',
                        parent=self._defined_styles.get('Normal'),
                        alignment=self._bottom_tip_align
                    )
                )
            )

    def finish(self):
        self._story = []

        self._build_invoice_info()
        self._build_service_provider_and_client_info()
        self._build_items()
        self._build_transactions()
        self._build_bottom_tip()

        kwargs = {}
        if self.is_paid:
            kwargs['onFirstPage'] = PaidStamp(7 * inch, 5.8 * inch)

        self.build(self._story, **kwargs)