ScoDoc/app/scodoc/sco_bulletins_generator.py

# -*- mode: python -*-
# -*- coding: utf-8 -*-

##############################################################################
#
# Gestion scolarite IUT
#
# Copyright (c) 1999 - 2022 Emmanuel Viennet.  All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
#   Emmanuel Viennet      emmanuel.viennet@gmail.com
#
##############################################################################

"""Génération des bulletins de note: super-classe pour les générateurs (HTML et PDF)

class BulletinGenerator:
 description
 supported_formats = [ 'pdf', 'html' ]
 .bul_title_pdf()
 .bul_table(format)
 .bul_part_below(format)
 .bul_signatures_pdf()

 .__init__ et .generate(format) methodes appelees par le client (sco_bulletin)

La préférence 'bul_class_name' donne le nom de la classe generateur.
La préférence 'bul_pdf_class_name' est obsolete (inutilisée).


"""
import collections
import io
import time
import traceback


import reportlab
from reportlab.platypus import SimpleDocTemplate, Paragraph, Spacer, Frame, PageBreak
from reportlab.platypus import Table, TableStyle, Image, KeepInFrame

from flask import request
from flask_login import current_user

from app.scodoc import sco_utils as scu
from app.scodoc.sco_exceptions import NoteProcessError
from app import log
from app.scodoc import sco_formsemestre
from app.scodoc import sco_pdf
from app.scodoc.sco_pdf import PDFLOCK
import sco_version

# Liste des types des classes de générateurs de bulletins PDF:
BULLETIN_CLASSES = collections.OrderedDict()


def register_bulletin_class(klass):
    BULLETIN_CLASSES[klass.__name__] = klass


def bulletin_class_descriptions():
    return [x.description for x in BULLETIN_CLASSES.values()]


def bulletin_class_names():
    return list(BULLETIN_CLASSES.keys())


def bulletin_default_class_name():
    return bulletin_class_names()[0]


def bulletin_get_class(class_name):
    return BULLETIN_CLASSES[class_name]


def bulletin_get_class_name_displayed(formsemestre_id):
    """Le nom du générateur utilisé, en clair"""
    from app.scodoc import sco_preferences

    bul_class_name = sco_preferences.get_preference("bul_class_name", formsemestre_id)
    try:
        gen_class = bulletin_get_class(bul_class_name)
        return gen_class.description
    except:
        return "invalide ! (voir paramètres)"


class BulletinGenerator(object):
    "Virtual superclass for PDF bulletin generators" ""
    # Here some helper methods
    # see sco_bulletins_standard.BulletinGeneratorStandard subclass for real methods
    supported_formats = []  # should list supported formats, eg [ 'html', 'pdf' ]
    description = "superclass for bulletins"  # description for user interface

    def __init__(
        self,
        infos,
        authuser=None,
        version="long",
        filigranne=None,
        server_name=None,
    ):
        from app.scodoc import sco_preferences

        if not version in scu.BULLETINS_VERSIONS:
            raise ValueError("invalid version code !")
        self.infos = infos
        self.authuser = authuser  # nécessaire pour version HTML qui contient liens dépendant de l'utilisateur
        self.version = version
        self.filigranne = filigranne
        self.server_name = server_name
        # Store preferences for convenience:
        formsemestre_id = self.infos["formsemestre_id"]
        self.preferences = sco_preferences.SemPreferences(formsemestre_id)
        self.diagnostic = None  # error message if any problem
        # Common PDF styles:
        #  - Pour tous les champs du bulletin sauf les cellules de table:
        self.FieldStyle = reportlab.lib.styles.ParagraphStyle({})
        self.FieldStyle.fontName = self.preferences["SCOLAR_FONT_BUL_FIELDS"]
        self.FieldStyle.fontSize = self.preferences["SCOLAR_FONT_SIZE"]
        self.FieldStyle.firstLineIndent = 0
        #  - Pour les cellules de table:
        self.CellStyle = reportlab.lib.styles.ParagraphStyle({})
        self.CellStyle.fontSize = self.preferences["SCOLAR_FONT_SIZE"]
        self.CellStyle.fontName = self.preferences["SCOLAR_FONT"]
        self.CellStyle.leading = (
            1.0 * self.preferences["SCOLAR_FONT_SIZE"]
        )  # vertical space
        # Marges du document PDF
        self.margins = (
            self.preferences["left_margin"],
            self.preferences["top_margin"],
            self.preferences["right_margin"],
            self.preferences["bottom_margin"],
        )

    def get_filename(self):
        """Build a filename to be proposed to the web client"""
        sem = sco_formsemestre.get_formsemestre(self.infos["formsemestre_id"])
        return scu.bul_filename(sem, self.infos["etud"], "pdf")

    def generate(self, format="", stand_alone=True):
        """Return bulletin in specified format"""
        if not format in self.supported_formats:
            raise ValueError("unsupported bulletin format (%s)" % format)
        try:
            PDFLOCK.acquire()  # this lock is necessary since reportlab is not re-entrant
            if format == "html":
                return self.generate_html()
            elif format == "pdf":
                return self.generate_pdf(stand_alone=stand_alone)
            else:
                raise ValueError("invalid bulletin format (%s)" % format)
        finally:
            PDFLOCK.release()

    def generate_html(self):
        """Return bulletin as an HTML string"""
        H = ['<div class="notes_bulletin">']
        # table des notes:
        H.append(self.bul_table(format="html"))  # pylint: disable=no-member
        # infos sous la table:
        H.append(self.bul_part_below(format="html"))  # pylint: disable=no-member
        H.append("</div>")
        return "\n".join(H)

    def generate_pdf(self, stand_alone=True):
        """Build PDF bulletin from distinct parts
        Si stand_alone, génère un doc PDF complet et renvoie une string
        Sinon, renvoie juste une liste d'objets PLATYPUS pour intégration
        dans un autre document.
        """
        from app.scodoc import sco_preferences

        formsemestre_id = self.infos["formsemestre_id"]

        # partie haute du bulletin
        objects = self.bul_title_pdf()  # pylint: disable=no-member
        # table des notes
        objects += self.bul_table(format="pdf")  # pylint: disable=no-member
        # infos sous la table
        objects += self.bul_part_below(format="pdf")  # pylint: disable=no-member
        # signatures
        objects += self.bul_signatures_pdf()  # pylint: disable=no-member

        # Réduit sur une page
        objects = [KeepInFrame(0, 0, objects, mode="shrink")]
        #
        if not stand_alone:
            objects.append(PageBreak())  # insert page break at end
            return objects
        else:
            # Generation du document PDF
            sem = sco_formsemestre.get_formsemestre(formsemestre_id)
            report = io.BytesIO()  # in-memory document, no disk file
            document = sco_pdf.BaseDocTemplate(report)
            document.addPageTemplates(
                sco_pdf.ScolarsPageTemplate(
                    document,
                    author="%s %s (E. Viennet) [%s]"
                    % (sco_version.SCONAME, sco_version.SCOVERSION, self.description),
                    title="Bulletin %s de %s"
                    % (sem["titremois"], self.infos["etud"]["nomprenom"]),
                    subject="Bulletin de note",
                    margins=self.margins,
                    server_name=self.server_name,
                    filigranne=self.filigranne,
                    preferences=sco_preferences.SemPreferences(formsemestre_id),
                )
            )
            document.build(objects)
            data = report.getvalue()
        return data

    def buildTableObject(self, P, pdfTableStyle, colWidths):
        """Utility used by some old-style generators.
        Build a platypus Table instance from a nested list of cells, style and widths.
        P: table, as a list of lists
        PdfTableStyle: commandes de style pour la table (reportlab)
        """
        try:
            # put each table cell in a Paragraph
            Pt = [
                [Paragraph(sco_pdf.SU(x), self.CellStyle) for x in line] for line in P
            ]
        except:
            # enquête sur exception intermittente...
            log("*** bug in PDF buildTableObject:")
            log("P=%s" % P)
            # compris: reportlab is not thread safe !
            #   see http://two.pairlist.net/pipermail/reportlab-users/2006-June/005037.html
            # (donc maintenant protégé dans ScoDoc par un Lock global)
            self.diagnostic = "erreur lors de la génération du PDF<br/>"
            self.diagnostic += "<pre>" + traceback.format_exc() + "</pre>"
            return []
        return Table(Pt, colWidths=colWidths, style=pdfTableStyle)


# ---------------------------------------------------------------------------
def make_formsemestre_bulletinetud(
    infos,
    version="long",  # short, long, selectedevals
    format="pdf",  # html, pdf
    stand_alone=True,
):
    """Bulletin de notes

    Appelle une fonction générant le bulletin au format spécifié à partir des informations infos,
    selon les préférences du semestre.

    """
    from app.scodoc import sco_preferences

    if not version in scu.BULLETINS_VERSIONS:
        raise ValueError("invalid version code !")

    formsemestre_id = infos["formsemestre_id"]
    bul_class_name = sco_preferences.get_preference("bul_class_name", formsemestre_id)
    try:
        gen_class = bulletin_get_class(bul_class_name)
    except:
        raise ValueError(
            "Type de bulletin PDF invalide (paramètre: %s)" % bul_class_name
        )

    try:
        PDFLOCK.acquire()
        bul_generator = gen_class(
            infos,
            authuser=current_user,
            version=version,
            filigranne=infos["filigranne"],
            server_name=request.url_root,
        )
        if format not in bul_generator.supported_formats:
            # use standard generator
            log(
                "Bulletin format %s not supported by %s, using %s"
                % (format, bul_class_name, bulletin_default_class_name())
            )
            bul_class_name = bulletin_default_class_name()
            gen_class = bulletin_get_class(bul_class_name)
            bul_generator = gen_class(
                infos,
                authuser=current_user,
                version=version,
                filigranne=infos["filigranne"],
                server_name=request.url_root,
            )

        data = bul_generator.generate(format=format, stand_alone=stand_alone)
    finally:
        PDFLOCK.release()

    if bul_generator.diagnostic:
        log("bul_error: %s" % bul_generator.diagnostic)
        raise NoteProcessError(bul_generator.diagnostic)

    filename = bul_generator.get_filename()

    return data, filename