python3+PyQt5 implements document printing function

#!/usr/bin/env python3
import math
import sys
import html
from PyQt5.QtPrintSupport import QPrinter,QPrintDialog
from PyQt5.QtCore import (QDate, QRectF, Qt)
from PyQt5.QtWidgets import (QApplication,QDialog, 
 QHBoxLayout,QPushButton, QTableWidget, QTableWidgetItem,QVBoxLayout)
from PyQt5.QtGui import (QFont,QFontMetrics,QPainter,QTextCharFormat,
    QTextCursor, QTextDocument, QTextFormat,
    QTextOption, QTextTableFormat,
    QPixmap,QTextBlockFormat)
import qrc_resources


from PyQt5.QtPrintSupport import QPrinter,QPrintDialog
from PyQt5.QtCore import (QDate, QRectF, Qt)
from PyQt5.QtWidgets import (QApplication,QDialog, 
 QHBoxLayout,QPushButton, QTableWidget, QTableWidgetItem,QVBoxLayout)
from PyQt5.QtGui import (QFont,QFontMetrics,QPainter,QTextCharFormat,
    QTextCursor, QTextDocument, QTextFormat,
    QTextOption, QTextTableFormat,
    QPixmap,QTextBlockFormat)
import qrc_resources
DATE_FORMAT = "MMM d, yyyy"


class Statement(object):

 def __init__(self, company, contact, address):
 self.company = company
 self.contact = contact
 self.address = address
 self.transactions = [] # List of (QDate, float) two-tuples


 def balance(self):
 return sum([amount for date, amount in self.transactions])


class Form(QDialog):

 def __init__(self, parent=None):
 super(Form, self).__init__(parent)

 self.printer = QPrinter()
 self.printer.setPageSize(QPrinter.Letter)
 self.generateFakeStatements()
 self.table = QTableWidget()
 self.populateTable()

 cursorButton = QPushButton("Print via Q&Cursor")
 htmlButton = QPushButton("Print via &HTML")
 painterButton = QPushButton("Print via Q&Painter")
 quitButton = QPushButton("&Quit")

 buttonLayout = QHBoxLayout()
 buttonLayout.addWidget(cursorButton)
 buttonLayout.addWidget(htmlButton)
 buttonLayout.addWidget(painterButton)
 buttonLayout.addStretch()
 buttonLayout.addWidget(quitButton)
 layout = QVBoxLayout()
 layout.addWidget(self.table)
 layout.addLayout(buttonLayout)
 self.setLayout(layout)

 cursorButton.clicked.connect(self.printViaQCursor)
 htmlButton.clicked.connect(self.printViaHtml)
 painterButton.clicked.connect(self.printViaQPainter)
 quitButton.clicked.connect(self.accept)

 self.setWindowTitle("Printing")


 def generateFakeStatements(self):
 self.statements = []
 statement = Statement("Consality", "Ms S. Royal",
  "234 Rue Saint Hyacinthe, 750201, Paris")
 statement.transactions.append((QDate(2007, 8, 11), 2342))
 statement.transactions.append((QDate(2007, 9, 10), 2342))
 statement.transactions.append((QDate(2007, 10, 9), 2352))
 statement.transactions.append((QDate(2007, 10, 17), -1500))
 statement.transactions.append((QDate(2007, 11, 12), 2352))
 statement.transactions.append((QDate(2007, 12, 10), 2352))
 statement.transactions.append((QDate(2007, 12, 20), -7500))
 statement.transactions.append((QDate(2007, 12, 20), 250))
 statement.transactions.append((QDate(2008, 1, 10), 2362))
 self.statements.append(statement)

 statement = Statement("Demamitur Plc", "Mr G. Brown",
  "14 Tall Towers, Tower Hamlets, London, WC1 3BX")
 statement.transactions.append((QDate(2007, 5, 21), 871))
 statement.transactions.append((QDate(2007, 6, 20), 542))
 statement.transactions.append((QDate(2007, 7, 20), 1123))
 statement.transactions.append((QDate(2007, 7, 20), -1928))
 statement.transactions.append((QDate(2007, 8, 13), -214))
 statement.transactions.append((QDate(2007, 9, 15), -3924))
 statement.transactions.append((QDate(2007, 9, 15), 2712))
 statement.transactions.append((QDate(2007, 9, 15), -273))
 #statement.transactions.append((QDate(2007, 11, 8), -728))
 #statement.transactions.append((QDate(2008, 2, 7), 228))
 #statement.transactions.append((QDate(2008, 3, 13), -508))
 #statement.transactions.append((QDate(2008, 3, 22), -2481))
 #statement.transactions.append((QDate(2008, 4, 5), 195))
 self.statements.append(statement)


 def populateTable(self):
 headers = ["Company", "Contact", "Address", "Balance"]
 self.table.setColumnCount(len(headers))
 self.table.setHorizontalHeaderLabels(headers)
 self.table.setRowCount(len(self.statements))
 for row, statement in enumerate(self.statements):
  self.table.setItem(row, 0, QTableWidgetItem(statement.company))
  self.table.setItem(row, 1, QTableWidgetItem(statement.contact))
  self.table.setItem(row, 2, QTableWidgetItem(statement.address))
  item = QTableWidgetItem("$ {0:,.2f}".format(float(statement.balance())))
  item.setTextAlignment(Qt.AlignRight|Qt.AlignVCenter)
  self.table.setItem(row, 3, item)
 self.table.resizeColumnsToContents()


 def printViaHtml(self):
 htmltext = ""
 for statement in self.statements:
  date = QDate.currentDate().toString(DATE_FORMAT)
  address = html.escape(statement.address).replace(
   ",", "<br>")
  contact = html.escape(statement.contact)
  balance = statement.balance()
  htmltext += ("<p align=right><img src=':/logo.png'></p>"
   "<p align=right>Greasy Hands Ltd."
   "<br>New Lombard Street"
   "<br>London<br>WC13 4PX<br>{0}</p>"
   "<p>{1}</p><p>Dear {2},</p>"
   "<p>The balance of your account is $ {3:,.2f}.").format(
   date, address, contact, float(balance))
  if balance < 0:
  htmltext += (" <p><font color=red><b>Please remit the "
    "amount owing immediately.</b></font>")
  else:
  htmltext += (" We are delighted to have done business "
    "with you.")
  htmltext += ("</p><p> </p><p>"
   "<table border=1 cellpadding=2 "
   "cellspacing=2><tr><td colspan=3>"
   "Transactions</td></tr>")
  for date, amount in statement.transactions:
  color, status = "black", "Credit"
  if amount < 0:
   color, status = "red", "Debit"
  htmltext += ("<tr><td align=right>{0}</td>"
    "<td>{1}</td><td align=right>"
    "<font color={2}>$ {3:,.2f}</font></td></tr>".format(
    date.toString(DATE_FORMAT), status, color,float(abs(amount))))
  htmltext += ("</table></p><p style='page-break-after:always;'>"
   "We hope to continue doing "
   "business with you,<br>Yours sincerely,"
   "<br><br>K. Longrey, Manager</p>")
 dialog = QPrintDialog(self.printer, self)
 if dialog.exec_():
  document = QTextDocument()
  document.setHtml(htmltext)
  document.print_(self.printer)

 def printViaQCursor(self):
 dialog = QPrintDialog(self.printer, self)
 if not dialog.exec_():
  return
 logo = QPixmap(":/logo.png")
 headFormat = QTextBlockFormat()
 headFormat.setAlignment(Qt.AlignLeft)
 headFormat.setTextIndent(
  self.printer.pageRect().width() - logo.width() - 216)
 bodyFormat = QTextBlockFormat()
 bodyFormat.setAlignment(Qt.AlignJustify)
 lastParaBodyFormat = QTextBlockFormat(bodyFormat)
 lastParaBodyFormat.setPageBreakPolicy(
  QTextFormat.PageBreak_AlwaysAfter)
 rightBodyFormat = QTextBlockFormat()
 rightBodyFormat.setAlignment(Qt.AlignRight)
 headCharFormat = QTextCharFormat()
 headCharFormat.setFont(QFont("Helvetica", 10))
 bodyCharFormat = QTextCharFormat()
 bodyCharFormat.setFont(QFont("Times", 11))
 redBodyCharFormat = QTextCharFormat(bodyCharFormat)
 redBodyCharFormat.setForeground(Qt.red)
 tableFormat = QTextTableFormat()
 tableFormat.setBorder(1)
 tableFormat.setCellPadding(2)

 document = QTextDocument()
 cursor = QTextCursor(document)
 mainFrame = cursor.currentFrame()
 page = 1
 for statement in self.statements:
  cursor.insertBlock(headFormat, headCharFormat)
  cursor.insertImage(":/logo.png")
  for text in ("Greasy Hands Ltd.", "New Lombard Street",
    "London", "WC13 4PX",
    QDate.currentDate().toString(DATE_FORMAT)):
  cursor.insertBlock(headFormat, headCharFormat)
  cursor.insertText(text)
  for line in statement.address.split(", "):
  cursor.insertBlock(bodyFormat, bodyCharFormat)
  cursor.insertText(line)
  cursor.insertBlock(bodyFormat)
  cursor.insertBlock(bodyFormat, bodyCharFormat)
  cursor.insertText("Dear {0},".format(statement.contact))
  cursor.insertBlock(bodyFormat)
  cursor.insertBlock(bodyFormat, bodyCharFormat)
  balance = statement.balance()
  cursor.insertText("The balance of your account is $ {0:,.2f}.".format(float(balance)))
  if balance < 0:
  cursor.insertBlock(bodyFormat, redBodyCharFormat)
  cursor.insertText("Please remit the amount owing "
     "immediately.")
  else:
  cursor.insertBlock(bodyFormat, bodyCharFormat)
  cursor.insertText("We are delighted to have done "
     "business with you.")
  cursor.insertBlock(bodyFormat, bodyCharFormat)
  cursor.insertText("Transactions:")
  table = cursor.insertTable(len(statement.transactions), 3,
     tableFormat)
  row = 0
  for date, amount in statement.transactions:
  cellCursor = table.cellAt(row, 0).firstCursorPosition()
  cellCursor.setBlockFormat(rightBodyFormat)
  cellCursor.insertText(date.toString(DATE_FORMAT),
     bodyCharFormat)
  cellCursor = table.cellAt(row, 1).firstCursorPosition()
  if amount > 0:
   cellCursor.insertText("Credit", bodyCharFormat)
  else:
   cellCursor.insertText("Debit", bodyCharFormat)
  cellCursor = table.cellAt(row, 2).firstCursorPosition()
  cellCursor.setBlockFormat(rightBodyFormat)
  format = bodyCharFormat
  if amount < 0:
   format = redBodyCharFormat
  cellCursor.insertText("$ {0:,.2f}".format(float(amount)), format)
  row += 1
  cursor.setPosition(mainFrame.lastPosition())
  cursor.insertBlock(bodyFormat, bodyCharFormat)
  cursor.insertText("We hope to continue doing business "
    "with you,")
  cursor.insertBlock(bodyFormat, bodyCharFormat)
  cursor.insertText("Yours sincerely")
  cursor.insertBlock(bodyFormat)
  if page == len(self.statements):
  cursor.insertBlock(bodyFormat, bodyCharFormat)
  else:
  cursor.insertBlock(lastParaBodyFormat, bodyCharFormat)
  cursor.insertText("K. Longrey, Manager")
  page += 1
 document.print_(self.printer)


 def printViaQPainter(self):
 dialog = QPrintDialog(self.printer, self)
 if not dialog.exec_():
  return
 LeftMargin = 72
 sansFont = QFont("Helvetica", 10)
 sansLineHeight = QFontMetrics(sansFont).height()
 serifFont = QFont("Times", 11)
 fm = QFontMetrics(serifFont)
 DateWidth = fm.width(" September 99, 2999 ")
 CreditWidth = fm.width(" Credit ")
 AmountWidth = fm.width(" W999999.99 ")
 serifLineHeight = fm.height()
 logo = QPixmap(":/logo.png")
 painter = QPainter(self.printer)
 pageRect = self.printer.pageRect()
 page = 1
 for statement in self.statements:
  painter.save()
  y = 0
  x = pageRect.width() - logo.width() - LeftMargin
  painter.drawPixmap(x, 0, logo)
  y += logo.height() + sansLineHeight
  painter.setFont(sansFont)
  painter.drawText(x, y, "Greasy Hands Ltd.")
  y += sansLineHeight
  painter.drawText(x, y, "New Lombard Street")
  y += sansLineHeight
  painter.drawText(x, y, "London")
  y += sansLineHeight
  painter.drawText(x, y, "WC13 4PX")
  y += sansLineHeight
  painter.drawText(x, y,
   QDate.currentDate().toString(DATE_FORMAT))
  y += sansLineHeight
  painter.setFont(serifFont)
  x = LeftMargin
  for line in statement.address.split(", "):
  painter.drawText(x, y, line)
  y += serifLineHeight
  y += serifLineHeight
  painter.drawText(x, y, "Dear {0},".format(statement.contact))
  y += serifLineHeight

  balance = statement.balance()
  painter.drawText(x, y, "The balance of your account is $ {0:,.2f}".format(float(balance)))
  y += serifLineHeight
  if balance < 0:
  painter.setPen(Qt.red)
  text = "Please remit the amount owing immediately."
  else:
  text = ("We are delighted to have done business "
   "with you.")
  painter.drawText(x, y, text)
  painter.setPen(Qt.black)
  y += int(serifLineHeight * 1.5)
  painter.drawText(x, y, "Transactions:")
  y += serifLineHeight

  option = QTextOption(Qt.AlignRight|Qt.AlignVCenter)
  for date, amount in statement.transactions:
  x = LeftMargin
  h = int(fm.height() * 1.3)
  painter.drawRect(x, y, DateWidth, h)
  painter.drawText(
   QRectF(x + 3, y + 3, DateWidth - 6, h - 6),
   date.toString(DATE_FORMAT), option)
  x += DateWidth
  painter.drawRect(x, y, CreditWidth, h)
  text = "Credit"
  if amount < 0:
   text = "Debit"
  painter.drawText(
   QRectF(x + 3, y + 3, CreditWidth - 6, h - 6),
   text, option)
  x += CreditWidth
  painter.drawRect(x, y, AmountWidth, h)
  if amount < 0:
   painter.setPen(Qt.red)
  painter.drawText(
   QRectF(x + 3, y + 3, AmountWidth - 6, h - 6),
   "$ {0:,.2f}".format(float(amount)),
   option)
  painter.setPen(Qt.black)
  y += h
  y += serifLineHeight
  x = LeftMargin
  painter.drawText(x, y, "We hope to continue doing "
     "business with you,")
  y += serifLineHeight
  painter.drawText(x, y, "Yours sincerely")
  y += serifLineHeight * 3
  painter.drawText(x, y, "K. Longrey, Manager")
  x = LeftMargin
  y = pageRect.height() - 72
  painter.drawLine(x, y, pageRect.width() - LeftMargin, y)
  y += 2
  font = QFont("Helvetica", 9)
  font.setItalic(True)
  painter.setFont(font)
  option = QTextOption(Qt.AlignCenter)
  option.setWrapMode(QTextOption.WordWrap)
  painter.drawText(
   QRectF(x, y, pageRect.width() - 2 * LeftMargin, 31),
   "The contents of this letter are for information "
   "only and do not form part of any contract.",
   option)
  page += 1
  if page <= len(self.statements):
  self.printer.newPage()
  painter.restore()


if __name__ == "__main__":
 app = QApplication(sys.argv)
 form = Form()
 form.show()
 app.exec_()