#! /usr/bin/env python
# -*- Mode: python; tab-width: 4; indent-tabs-mode: t -*-
#
# This file is part of the LibreOffice project.
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#

"""
This script generates precompiled headers for a given
module and library.

Given a gmake makefile that belongs to some LO module:
1) Process the makefile to find source files (process_makefile).
2) For every source file, find all includes (process_source).
3) Uncommon and rare includes are filtered (remove_rare).
4) Conflicting headers are excluded (filter_ignore).
5) Local files to the source are excluded (Filter_Local).
6) Fixup missing headers that sources expect (fixup).
7) The resulting includes are sorted by category (sort_by_category).
8) The pch file is generated (generate).
"""

import sys
import re
import os
import unittest

CUTOFF = 1
EXCLUDE_MODULE = False
EXCLUDE_LOCAL = False
EXCLUDE_SYSTEM = True
SILENT = False

# System includes: oox, sal, sd, svl, vcl

INCLUDE = False
EXCLUDE = True
DEFAULTS = \
{
#    module.library : (min, system, module, local), best time
    'accessibility.acc'                 : ( 4, EXCLUDE, INCLUDE, INCLUDE), #   7.8
    'basctl.basctl'                     : ( 3, EXCLUDE, INCLUDE, EXCLUDE), #  11.9
    'basegfx.basegfx'                   : ( 3, EXCLUDE, EXCLUDE, INCLUDE), #   3.8
    'basic.sb'                          : ( 2, EXCLUDE, EXCLUDE, INCLUDE), #  10.7
    'chart2.chartcontroller'            : ( 6, EXCLUDE, INCLUDE, INCLUDE), #  18.4
    'chart2.chartcore'                  : ( 3, EXCLUDE, EXCLUDE, INCLUDE), #  22.5
    'chart2.chartopengl'                : (12, EXCLUDE, EXCLUDE, EXCLUDE), #   5.3
    'comphelper.comphelper'             : ( 4, EXCLUDE, INCLUDE, INCLUDE), #   7.6
    'configmgr.configmgr'               : ( 6, EXCLUDE, INCLUDE, INCLUDE), #   6.0
    'connectivity.ado'                  : ( 2, EXCLUDE, EXCLUDE, EXCLUDE), #   6.4
    'connectivity.calc'                 : ( 2, EXCLUDE, EXCLUDE, EXCLUDE), #   4.6
    'connectivity.dbase'                : ( 2, EXCLUDE, INCLUDE, INCLUDE), #   5.2
    'connectivity.dbpool2'              : ( 5, EXCLUDE, INCLUDE, EXCLUDE), #   3.0
    'connectivity.dbtools'              : ( 2, EXCLUDE, EXCLUDE, INCLUDE), #   0.8
    'connectivity.file'                 : ( 2, EXCLUDE, INCLUDE, EXCLUDE), #   5.1
    'connectivity.firebird_sdbc'        : ( 2, EXCLUDE, EXCLUDE, EXCLUDE), #   5.1
    'connectivity.flat'                 : ( 2, EXCLUDE, INCLUDE, INCLUDE), #   4.6
    'connectivity.mysql'                : ( 4, EXCLUDE, INCLUDE, EXCLUDE), #   3.4
    'connectivity.odbc'                 : ( 2, EXCLUDE, EXCLUDE, INCLUDE), #   5.0
    'connectivity.postgresql-sdbc-impl' : ( 3, EXCLUDE, EXCLUDE, EXCLUDE), #   6.7
    'cppcanvas.cppcanvas'               : (11, EXCLUDE, INCLUDE, INCLUDE), #   4.8
    'cppuhelper.cppuhelper'             : ( 3, EXCLUDE, EXCLUDE, EXCLUDE), #   4.6
    'cui.cui'                           : ( 8, EXCLUDE, INCLUDE, EXCLUDE), #  19.7
    'dbaccess.dba'                      : ( 6, EXCLUDE, INCLUDE, INCLUDE), #  13.8
    'dbaccess.dbaxml'                   : ( 2, EXCLUDE, EXCLUDE, EXCLUDE), #   6.5
    'dbaccess.dbmm'                     : (10, EXCLUDE, INCLUDE, EXCLUDE), #   4.3
    'dbaccess.dbu'                      : (12, EXCLUDE, EXCLUDE, EXCLUDE), #  23.6
    'dbaccess.sdbt'                     : ( 1, EXCLUDE, INCLUDE, EXCLUDE), #   2.9
    'desktop.deployment'                : ( 3, EXCLUDE, EXCLUDE, EXCLUDE), #   6.1
    'desktop.deploymentgui'             : ( 3, EXCLUDE, EXCLUDE, EXCLUDE), #   5.7
    'desktop.deploymentmisc'            : ( 3, EXCLUDE, EXCLUDE, EXCLUDE), #   3.4
    'desktop.sofficeapp'                : ( 6, EXCLUDE, INCLUDE, INCLUDE), #   6.5
    'drawinglayer.drawinglayer'         : ( 4, EXCLUDE, EXCLUDE, EXCLUDE), #   7.4
    'editeng.editeng'                   : ( 5, EXCLUDE, INCLUDE, EXCLUDE), #  13.0
    'forms.frm'                         : ( 2, EXCLUDE, EXCLUDE, EXCLUDE), #  14.2
    'framework.fwe'                     : (10, EXCLUDE, INCLUDE, EXCLUDE), #   5.5
    'framework.fwi'                     : ( 9, EXCLUDE, INCLUDE, EXCLUDE), #   3.4
    'framework.fwk'                     : ( 7, EXCLUDE, INCLUDE, INCLUDE), #  14.8
    'framework.fwl'                     : ( 5, EXCLUDE, INCLUDE, INCLUDE), #   5.1
    'hwpfilter.hwp'                     : ( 3, EXCLUDE, INCLUDE, INCLUDE), #   6.0
    'lotuswordpro.lwpft'                : ( 2, EXCLUDE, EXCLUDE, EXCLUDE), #  11.6
    'oox.oox'                           : ( 6, EXCLUDE, EXCLUDE, INCLUDE), #  28.2
    'package.package2'                  : ( 3, EXCLUDE, INCLUDE, INCLUDE), #   4.5
    'package.xstor'                     : ( 2, EXCLUDE, INCLUDE, EXCLUDE), #   3.8
    'reportdesign.rpt'                  : ( 9, EXCLUDE, INCLUDE, INCLUDE), #   9.4
    'reportdesign.rptui'                : ( 4, EXCLUDE, INCLUDE, INCLUDE), #  13.1
    'reportdesign.rptxml'               : ( 2, EXCLUDE, EXCLUDE, INCLUDE), #   7.6
    'sal.sal'                           : ( 2, EXCLUDE, EXCLUDE, INCLUDE), #   4.2
    'sc.sc'                             : (12, EXCLUDE, INCLUDE, INCLUDE), #  92.6
    'sc.scfilt'                         : ( 4, EXCLUDE, EXCLUDE, INCLUDE), #  39.9
    'sc.scui'                           : ( 1, EXCLUDE, EXCLUDE, INCLUDE), #  15.0
    'sc.vbaobj'                         : ( 1, EXCLUDE, EXCLUDE, INCLUDE), #  17.3
    'sd.sd'                             : ( 4, EXCLUDE, EXCLUDE, INCLUDE), #  47.4
    'sd.sdui'                           : ( 4, EXCLUDE, INCLUDE, INCLUDE), #   9.4
    'sdext.PresentationMinimizer'       : ( 2, EXCLUDE, INCLUDE, INCLUDE), #   4.1
    'sdext.PresenterScreen'             : ( 2, EXCLUDE, INCLUDE, EXCLUDE), #   7.1
    'sfx2.sfx'                          : ( 3, EXCLUDE, EXCLUDE, EXCLUDE), #  27.4
    'slideshow.slideshow'               : ( 4, EXCLUDE, INCLUDE, EXCLUDE), #  10.8
    'sot.sot'                           : ( 5, EXCLUDE, EXCLUDE, INCLUDE), #   3.1
    'starmath.sm'                       : ( 5, EXCLUDE, EXCLUDE, INCLUDE), #  10.9
    'svgio.svgio'                       : ( 8, EXCLUDE, EXCLUDE, INCLUDE), #   4.3
    'svl.svl'                           : ( 6, EXCLUDE, EXCLUDE, EXCLUDE), #   7.6
    'svtools.svt'                       : ( 4, EXCLUDE, INCLUDE, EXCLUDE), #  17.6
    'svx.svx'                           : ( 3, EXCLUDE, EXCLUDE, INCLUDE), #  20.7
    'svx.svxcore'                       : ( 7, EXCLUDE, INCLUDE, EXCLUDE), #  37.0
    'sw.msword'                         : ( 4, EXCLUDE, INCLUDE, INCLUDE), #  22.4
    'sw.sw'                             : ( 7, EXCLUDE, EXCLUDE, INCLUDE), # 129.6
    'sw.swui'                           : ( 3, EXCLUDE, INCLUDE, INCLUDE), #  26.1
    'sw.vbaswobj'                       : ( 4, EXCLUDE, INCLUDE, INCLUDE), #  13.1
    'tools.tl'                          : ( 5, EXCLUDE, EXCLUDE, EXCLUDE), #   4.2
    'unotools.utl'                      : ( 3, EXCLUDE, EXCLUDE, INCLUDE), #   7.0
    'unoxml.unoxml'                     : ( 1, EXCLUDE, EXCLUDE, EXCLUDE), #   4.6
    'uui.uui'                           : ( 4, EXCLUDE, EXCLUDE, EXCLUDE), #   4.9
    'vbahelper.msforms'                 : ( 3, EXCLUDE, INCLUDE, INCLUDE), #   5.2
    'vbahelper.vbahelper'               : ( 3, EXCLUDE, EXCLUDE, INCLUDE), #   7.0
    'vcl.vcl'                           : ( 6, EXCLUDE, INCLUDE, INCLUDE), #  35.7
    'writerfilter.writerfilter'         : ( 5, EXCLUDE, EXCLUDE, EXCLUDE), #  19.7/27.3
    'xmloff.xo'                         : ( 7, EXCLUDE, INCLUDE, INCLUDE), #  22.1
    'xmloff.xof'                        : ( 1, EXCLUDE, EXCLUDE, INCLUDE), #   4.4
    'xmlscript.xmlscript'               : ( 4, EXCLUDE, EXCLUDE, INCLUDE), #   3.6
    'xmlsecurity.xmlsecurity'           : ( 6, EXCLUDE, INCLUDE, INCLUDE), #   5.1
    'xmlsecurity.xsec_fw'               : ( 2, EXCLUDE, INCLUDE, EXCLUDE), #   2.7
    'xmlsecurity.xsec_xmlsec'           : ( 2, EXCLUDE, INCLUDE, INCLUDE), #   4.4
}

def remove_rare(raw, min_use=-1):
    """ Remove headers not commonly included.
        The minimum threshold is min_use.
    """
    # The minimum number of times a header
    # must be included to be in the PCH.
    min_use = min_use if min_use >= 0 else CUTOFF

    out = []
    if not raw or not len(raw):
        return out

    inc = sorted(raw)
    last = inc[0]
    count = 1
    for x in range(1, len(inc)):
        i = inc[x]
        if i == last:
            count += 1
        else:
            if count >= min_use:
                out.append(last)
            last = i
            count = 1

    # Last group.
    if count >= min_use:
        out.append(last)

    return out

def process_list(list, callable):
    """ Given a list and callable
        we pass each entry through
        the callable and only add to
        the output if not blank.
    """
    out = []
    for i in list:
        line = callable(i)
        if line and len(line):
            out.append(line)
    return out

def find_files(path, recurse=True):
    list = []
    for root, dir, files in os.walk(path):
        list += map(lambda x: os.path.join(root, x), files)
    return list

def get_filename(line):
    """ Strips the line from the
        '#include' and angled brakets
        and return the filename only.
    """
    if not len(line) or line[0] != '#':
        return line
    return re.sub(r'(.*#include\s*)<(.*)>(.*)', r'\2', line)

def is_c_runtime(inc):
    """ Heuristic-based detection of C/C++
        runtime headers.
        They are all-lowercase, with .h or
        no extension, filename only.
    """
    inc = get_filename(inc)

    if inc.endswith('.hxx') or inc.endswith('.hpp'):
        return False

    for c in inc:
        if c == '/':
            return False
        if c == '.':
            return inc.endswith('.h')
        if c.isupper():
            return False

    return True

def sanitize(raw):
    """ There are two forms of includes,
        those with <> and "".
        Technically, the difference is that
        the compiler can use an internal
        representation for an angled include,
        such that it doesn't have to be a file.
        For our purposes, there is no difference.
        Here, we convert everything to angled.
    """
    if not raw or not len(raw):
        return ''
    raw = raw.strip()
    if not len(raw):
        return ''
    return re.sub(r'(.*#include\s*)\"(.*)\"(.*)', r'#include <\2>', raw)

class Filter_Local(object):
    """ Filter headers local to a module.
        allow_public: allows include/module/file.hxx
                      #include <module/file.hxx>
        allow_module: allows module/inc/file.hxx
                      #include <file.hxx>
        allow_locals: allows module/source/file.hxx and
                             module/source/inc/file.hxx
                      #include <file.hxx>
    """
    def __init__(self, root, module, allow_public=True, allow_module=True, allow_locals=True):
        self.root = root
        self.module = module
        self.allow_public = allow_public
        self.allow_module = allow_module
        self.allow_locals = allow_locals
        self.public_prefix = '<' + self.module + '/'

        all = find_files(os.path.join(root, module))
        self.module = []
        self.locals = []
        mod_prefix = module + '/inc/'
        for i in all:
            if mod_prefix in i:
                self.module.append(i)
            else:
                self.locals.append(i)

    def is_public(self, line):
        return self.public_prefix in line

    def is_module(self, line):
        """ Returns True if in module/inc/... """
        filename = get_filename(line)
        for i in self.module:
            if i.endswith(filename):
                return True
        return False

    def is_local(self, line):
        """ Returns True if in module/source/... """
        filename = get_filename(line)
        for i in self.locals:
            if i.endswith(filename):
                return True
        return False

    def is_external(self, line):
        return is_c_runtime(line) and \
               not self.is_public(line) and \
               not self.is_module(line) and \
               not self.is_local(line)

    def find_local_file(self, line):
        """ Finds the header file in the module dir,
            but doesn't validate.
        """
        filename = get_filename(line)
        for i in self.locals:
            if i.endswith(filename):
                return i
        for i in self.module:
            if i.endswith(filename):
                return i
        return None

    def proc(self, line):
        assert line and len(line)
        assert line[0] != '<' and line[0] != '#'

        filename = get_filename(line)

        # Local with relative path.
        if filename.startswith('..'):
            # Exclude for now as we don't have cxx path.
            return ''

        # Locals are included first (by the compiler).
        if self.is_local(filename):
            return line if self.allow_locals and '/inc/' in filename else ''

        # Module headers are next.
        if self.is_module(filename):
            return line if self.allow_module else ''

        # Public headers are last.
        if self.is_public(line):
            return line if self.allow_public else ''

        # Leave out potentially unrelated files local
        # to some other module we can't include directly.
        if '/' not in filename and not self.is_external(filename):
            return ''

        # Unfiltered.
        return line

def filter_ignore(line, module):
    """ Filters includes from known
        problematic ones.
        Expects sanitized input.
    """
    assert line and len(line)

    # Always include files without extension.
    if '.' not in line:
        return line

    # Extract filenames for ease of comparison.
    line = get_filename(line)

    # Filter out all files that are not normal headers.
    if not line.endswith('.h') and \
       not line.endswith('.hxx') and \
       not line.endswith('.hpp') and \
       not line.endswith('.hdl'):
       return ''

    ignore_list = [
            'LibreOfficeKit/LibreOfficeKitEnums.h', # Needs special directives
            'LibreOfficeKit/LibreOfficeKitTypes.h', # Needs special directives
            'jerror.h',     # c++ unfriendly
            'jpeglib.h',    # c++ unfriendly
            'boost/spirit/include/classic_core.hpp', # depends on BOOST_SPIRIT_DEBUG
            'svtools/editimplementation.hxx' # no direct include
        ]

    if module == 'accessibility':
        ignore_list += [
            # STR_SVT_ACC_LISTENTRY_SELCTED_STATE redefined from svtools.hrc
            'accessibility/extended/textwindowaccessibility.hxx',
            ]
    if module == 'basic':
        ignore_list += [
            'basic/vbahelper.hxx',
            ]
    if module == 'connectivity':
        ignore_list += [
            'com/sun/star/beans/PropertyAttribute.hpp', # OPTIONAL defined via objbase.h
            'com/sun/star/sdbcx/Privilege.hpp', # DELETE defined via objbase.h
            ]
    if module == 'reportdesign':
        ignore_list += [
            'editeng/eeitemid.hxx', # macro redefined in ui/misc/UITools.cxx
            ]
    if module == 'sc':
        ignore_list += [
            'progress.hxx', # special directives
            'scslots.hxx',  # special directives
           ]
    if module == 'sd':
        ignore_list += [
            'sdgslots.hxx', # special directives
            'sdslots.hxx',  # special directives
            'svtools/sores.hxx', # redefines BMP_PLUGIN defined in svtools.hrc
           ]
    if module == 'sfx2':
        ignore_list += [
            'sfx2/recentdocsview.hxx', # Redefines ApplicationType defined in objidl.h
            'sfx2/sidebar/Sidebar.hxx',
            'sfx2/sidebar/UnoSidebar.hxx',
            'sfxslots.hxx', # externally defined types
            ]
    if module == 'sot':
        ignore_list += [
            'sysformats.hxx',   # Windows headers
            ]
    if module == 'svx':
        ignore_list += [
            'tbunosearchcontrollers.hxx', # Anonymous namespace
            ]
    if module == 'vcl':
        ignore_list += [
            'accmgr.hxx',   # redefines ImplAccelList
            'image.h',
            'jobset.h',
            'opengl/gdiimpl.hxx',
            'opengl/salbmp.hxx',
            'openglgdiimpl',   # ReplaceTextA
            'printdlg.hxx',
            'salinst.hxx',  # GetDefaultPrinterA
            'salprn.hxx',   # SetPrinterDataA
            'vcl/jobset.hxx',
            'vcl/oldprintadaptor.hxx',
            'vcl/opengl/OpenGLContext.hxx',
            'vcl/opengl/OpenGLHelper.hxx',  # Conflicts with X header on *ix
            'vcl/print.hxx',
            'vcl/prntypes.hxx', # redefines Orientation from filter/jpeg/Exif.hxx
            'vcl/sysdata.hxx',
            ]
    if module == 'xmloff':
        ignore_list += [
            'SchXMLExport.hxx', # SchXMLAutoStylePoolP.hxx not found
            'SchXMLImport.hxx', # enums redefined in draw\sdxmlimp_impl.hxx
            'XMLEventImportHelper.hxx', # NameMap redefined in XMLEventExport.hxx
            'xmloff/XMLEventExport.hxx', # enums redefined
            ]
    if module == 'xmlsecurity':
        ignore_list += [
            'xmlsec/crypto.h',
            'xmlsecurity/xmlsec-wrapper.h',
            ]

    for i in ignore_list:
        if line.startswith(i):
            return ''
        if i[0] == '*' and line.endswith(i[1:]):
            return ''
        if i[-1] == '*' and line.startswith(i[:-1]):
            return ''

    return line

def fixup(includes, module):
    """ Here we add any headers
        necessary in the pch.
        These could be known to be very
        common but for technical reasons
        left out of the pch by this generator.
        Or, they could be missing from the
        source files where they are used
        (probably because they had been
        in the old pch, they were missed).
        Also, these could be headers
        that make the build faster but
        aren't added automatically.
    """
    fixes = []
    def append(inc):
        # Add a space to exclude from
        # ignore bisecting.
        line = ' #include <{}>'.format(inc)
        try:
            i = fixes.index(inc)
            fixes[i] = inc
        except:
            fixes.append(inc)

    if module == 'basctl':
        if 'basslots.hxx' in includes:
            append('sfx2/msg.hxx')

    #if module == 'sc':
    #    if 'scslots.hxx' in includes:
    #        append('sfx2/msg.hxx')
    return fixes

def sort_by_category(list, module, filter_local):
    """ Move all 'system' headers first.
        Core files of osl, rtl, sal, next.
        Everything non-module-specific third.
        Last, module-specific headers.
    """
    sys = []
    boo = []
    cor = []
    rst = []
    mod = []

    prefix = '<' + module + '/'
    for i in list:
        if is_c_runtime(i):
            sys.append(i)
        elif '<boost/' in i:
            boo.append(i)
        elif '<osl' in i or '<rtl' in i or '<sal' in i or '<vcl' in i:
            cor.append(i)
        elif prefix in i:
            mod.append(i)
        else:
            rst.append(i)

    out = []
    out += sorted(sys)
    out += sorted(boo)
    out += sorted(cor)
    out += sorted(rst)
    out += sorted(mod)
    return out

def parse_makefile(groups, lines, lineno, lastif, ifstack):

    inobjects = False
    inelse = False
    os_cond_re = re.compile('(ifeq|ifneq)\s*\(\$\(OS\)\,(\w*)\)')

    line = lines[lineno]
    if line.startswith('if'):
        lastif = line
        if ifstack == 0:
            # Correction if first line is an if.
            lineno = parse_makefile(groups, lines, lineno, line, ifstack+1)
    else:
        lineno -= 1

    while lineno + 1 < len(lines):
        lineno += 1
        line = lines[lineno].strip()
        line = line.rstrip('\\').strip()
        #print('line #{}: {}'.format(lineno, line))
        if len(line) == 0:
            continue

        if line == '))':
            inobjects = False
        elif 'add_exception_objects' in line or \
             'add_cxxobject' in line:
             inobjects = True
             #print('inobjects')
             #if ifstack and not SILENT:
                #sys.stderr.write('Sources in a conditional, ignoring for now.\n')
        elif line.startswith('if'):
            lineno = parse_makefile(groups, lines, lineno, line, ifstack+1)
            continue
        elif line.startswith('endif'):
            if ifstack:
                return lineno
            continue
        elif line.startswith('else'):
            inelse = True
        elif inobjects:
            if EXCLUDE_SYSTEM and ifstack:
                continue
            file = line + '.cxx'
            if ',' in line or '(' in line or ')' in line:
                #print('passing: ' + line)
                pass # $if() probably, or something similar
            else:
                osname = ''
                if lastif:
                    if 'filter' in lastif:
                        # We can't grok filter, yet.
                        continue
                    match = os_cond_re.match(lastif)
                    if not match:
                        # We only support OS conditionals.
                        continue
                    in_out = match.group(1)
                    osname = match.group(2) if match else ''
                    if (in_out == 'ifneq' and not inelse) or \
                       (in_out == 'ifeq' and inelse):
                        osname = '!' + osname

                if osname not in groups:
                    groups[osname] = []
                groups[osname].append(file)

    return groups

def process_makefile(root, module, makefile):
    """ Parse a gmake makefile and extract
        source filenames from it.
    """

    filename = os.path.join(os.path.join(root, module), makefile)
    if not os.path.isfile(filename):
        sys.stderr.write('Error: Module {} has no makefile at {}.'.format(module, filename))

    groups = {'':[], 'ANDROID':[], 'IOS':[], 'WNT':[], 'LINUX':[], 'MACOSX':[]}

    with open(filename, 'r') as f:
        lines = f.readlines()
        groups = parse_makefile(groups, lines, lineno=0, lastif=None, ifstack=0)

    return groups

def process_source(root, module, filename, maxdepth=0):
    """ Process a source file to extract
        included headers.
        For now, skip on compiler directives.
        maxdepth is used when processing headers
        which typically have protecting ifndef.
    """

    ifdepth = 0
    lastif = ''
    raw_includes = []
    with open(filename, 'r') as f:
        for line in f:
            line = line.strip()
            if line.startswith('#if'):
                ifdepth += 1
                lastif = line
            elif line.startswith('#endif'):
                ifdepth -= 1
                lastif = '#if'
            elif line.startswith('#include'):
                if ifdepth <= maxdepth:
                    line = sanitize(line)
                    if line:
                        line = get_filename(line)
                    if line and len(line):
                        raw_includes.append(line)
                elif not SILENT:
                    sys.stderr.write('#include in {} : {}\n'.format(lastif, line))

    return raw_includes

def explode(root, module, includes, tree, filter_local, recurse):
    incpath = os.path.join(root, 'include')

    for inc in includes:
        filename = get_filename(inc)
        if filename in tree or len(filter_local.proc(filename)) == 0:
            continue

        try:
            # Module or Local header.
            filepath = filter_local.find_local_file(inc)
            if filepath:
                #print('trying loc: ' + filepath)
                incs = process_source(root, module, filepath, maxdepth=1)
                incs = map(get_filename, incs)
                incs = process_list(incs, lambda x: filter_ignore(x, module))
                incs = process_list(incs, filter_local.proc)
                tree[filename] = incs
                if recurse:
                    tree = explode(root, module, incs, tree, filter_local, recurse)
                #print('{} => {}'.format(filepath, tree[filename]))
                continue
        except:
            pass

        try:
            # Public header.
            filepath = os.path.join(incpath, filename)
            #print('trying pub: ' + filepath)
            incs = process_source(root, module, filepath, maxdepth=1)
            incs = map(get_filename, incs)
            incs = process_list(incs, lambda x: filter_ignore(x, module))
            incs = process_list(incs, filter_local.proc)
            tree[filename] = incs
            if recurse:
                tree = explode(root, module, incs, tree, filter_local, recurse)
            #print('{} => {}'.format(filepath, tree[filename]))
            continue
        except:
            pass

        # Failed, but remember to avoid searching again.
        tree[filename] = []

    return tree

def make_command_line():
    args = sys.argv[:]
    # Remove command line flags and
    # use internal flags.
    for i in xrange(len(args)-1, 0, -1):
        if args[i].startswith('--'):
            args.pop(i)

    args.append('--cutoff=' + str(CUTOFF))
    if EXCLUDE_SYSTEM:
        args.append('--exclude:system')
    else:
        args.append('--include:system')
    if EXCLUDE_MODULE:
        args.append('--exclude:module')
    else:
        args.append('--include:module')
    if EXCLUDE_LOCAL:
        args.append('--exclude:local')
    else:
        args.append('--include:local')

    return ' '.join(args)

def generate_includes(includes):
    """Generates the include lines of the pch.
    """
    lines = []
    for osname, group in includes.iteritems():
        if not len(group):
            continue

        if len(osname):
            not_eq = ''
            if osname[0] == '!':
                not_eq = '!'
                osname = osname[1:]
            lines.append('')
            lines.append('#if {}defined({})'.format(not_eq, osname))

        for i in group:
            lines.append(i)

        if len(osname):
            lines.append('#endif')

    return lines

def generate(includes, libname, filename, module):
    header = \
"""/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

/*
 This file has been autogenerated by update_pch.sh. It is possible to edit it
 manually (such as when an include file has been moved/renamed/removed). All such
 manual changes will be rewritten by the next run of update_pch.sh (which presumably
 also fixes all possible problems, so it's usually better to use it).
"""

    footer = \
"""
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
"""
    import datetime

    with open(filename, 'w') as f:
        f.write(header)
        f.write('\n Generated on {} using:\n {}\n'.format(
                datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
                make_command_line()))
        f.write('\n If after updating build fails, use the following command to locate conflicting headers:\n ./bin/update_pch_bisect {} "make {}.build" --find-conflicts\n*/\n'.format(
                filename, module))

        # svx needs this (sendreportw32.cxx)
        if module == 'svx' and libname == 'svx':
            svx_define = """
#ifdef _WIN32
#   define UNICODE
#   define _UNICODE
#endif
"""
            f.write(svx_define)

        # Dump the headers.
        f.write('\n')
        for i in includes:
            f.write(i + '\n')

        # Some libraries pull windows headers that aren't self contained.
        if (module == 'connectivity' and libname == 'ado') or \
           (module == 'xmlsecurity' and libname == 'xsec_xmlsec'):
            ado_define = """
// Cleanup windows header macro pollution.
#if defined(_WIN32) && defined(WINAPI)
#   include <postwin.h>
#   undef RGB
#endif
"""
            f.write(ado_define)

        f.write(footer)

def remove_from_tree(filename, tree):
    # Remove this file, if top-level.
    incs = tree.pop(filename, [])
    for i in incs:
        tree = remove_from_tree(i, tree)

    # Also remove if included from another.
    for (k, v) in tree.iteritems():
        if filename in v:
            v.remove(filename)

    return tree

def tree_to_list(includes, filename, tree):
    if filename in includes:
        return includes
    includes.append(filename)
    #incs = tree.pop(filename, [])
    incs = tree[filename] if filename in tree else []
    for i in incs:
        tree_to_list(includes, i, tree)

    return includes

def promote(includes):
    """ Common library headers are heavily
        referenced, even if they are included
        from a few places.
        Here we separate them to promote
        their inclusion in the final pch.
    """
    promo = []
    for inc in includes:
        if inc.startswith('boost') or \
           inc.startswith('sal') or \
           inc.startswith('osl') or \
           inc.startswith('rtl'):
            promo.append(inc)
    return promo

def make_pch_filename(root, module, libname):
    """ PCH files are stored here:
        <root>/<module>/inc/pch/precompiled_<libname>.hxx
    """

    path = os.path.join(root, module)
    path = os.path.join(path, 'inc')
    path = os.path.join(path, 'pch')
    path = os.path.join(path, 'precompiled_' + libname + '.hxx')
    return path

def main():

    global CUTOFF
    global EXCLUDE_MODULE
    global EXCLUDE_LOCAL
    global EXCLUDE_SYSTEM
    global SILENT

    root = '.'
    module = sys.argv[1]
    libname = sys.argv[2]
    header = make_pch_filename(root, module, libname)

    if not os.path.exists(os.path.join(root, module)):
        raise Exception('Error: module [{}] not found.'.format(module))

    key = '{}.{}'.format(module, libname)
    if key in DEFAULTS:
        # Load the module-specific defaults.
        CUTOFF = DEFAULTS[key][0]
        EXCLUDE_SYSTEM = DEFAULTS[key][1]
        EXCLUDE_MODULE = DEFAULTS[key][2]
        EXCLUDE_LOCAL = DEFAULTS[key][3]

    force_update = False
    for x in xrange(3, len(sys.argv)):
        i = sys.argv[x]
        if i.startswith('--cutoff='):
            CUTOFF = int(i.split('=')[1])
        elif i.startswith('--exclude:'):
            cat = i.split(':')[1]
            if cat == 'module':
                EXCLUDE_MODULE = True
            elif cat == 'local':
                EXCLUDE_LOCAL = True
            elif cat == 'system':
                EXCLUDE_SYSTEM = True
        elif i.startswith('--include:'):
            cat = i.split(':')[1]
            if cat == 'module':
                EXCLUDE_MODULE = False
            elif cat == 'local':
                EXCLUDE_LOCAL = False
            elif cat == 'system':
                EXCLUDE_SYSTEM = False
        elif i == '--silent':
            SILENT = True
        elif i == '--force':
            force_update = True
        else:
            sys.stderr.write('Unknown option [{}].'.format(i))
            return 1

    filter_local = Filter_Local(root, module, \
                                not EXCLUDE_MODULE, \
                                not EXCLUDE_LOCAL)

    # Read input.
    makefile = 'Library_{}.mk'.format(libname)
    groups = process_makefile(root, module, makefile)

    generic = []
    for osname, group in groups.iteritems():
        if not len(group):
            continue

        includes = []
        for filename in group:
            includes += process_source(root, module, filename)

        # Save unique top-level includes.
        unique = set(includes)
        promoted = promote(unique)

        # Process includes.
        includes = remove_rare(includes)
        includes = process_list(includes, lambda x: filter_ignore(x, module))
        includes = process_list(includes, filter_local.proc)

        # Remove the already included ones.
        for inc in includes:
            unique.discard(inc)

        # Explode the excluded ones.
        tree = {i:[] for i in includes}
        tree = explode(root, module, unique, tree, filter_local, not EXCLUDE_MODULE)

        # Remove the already included ones from the tree.
        for inc in includes:
            filename = get_filename(inc)
            tree = remove_from_tree(filename, tree)

        extra = []
        for (k, v) in tree.iteritems():
            extra += tree_to_list([], k, tree)

        promoted += promote(extra)
        promoted = process_list(promoted, lambda x: filter_ignore(x, module))
        promoted = process_list(promoted, filter_local.proc)
        promoted = set(promoted)
        # If a promoted header includes others, remove the rest.
        for (k, v) in tree.iteritems():
            if k in promoted:
                for i in v:
                    promoted.discard(i)
        includes += [x for x in promoted]

        extra = remove_rare(extra)
        extra = process_list(extra, lambda x: filter_ignore(x, module))
        extra = process_list(extra, filter_local.proc)
        includes += extra

        includes = [x for x in set(includes)]
        fixes = fixup(includes, module)
        fixes = map(lambda x: '#include <' + x + '>', fixes)

        includes = map(lambda x: '#include <' + x + '>', includes)
        sorted = sort_by_category(includes, module, filter_local)
        includes = fixes + sorted

        if len(osname):
            for i in generic:
                if i in includes:
                    includes.remove(i)

        groups[osname] = includes
        if not len(osname):
            generic = includes

    # Open the old pch and compare its contents
    # with new includes.
    # Clobber only if they are different.
    with open(header, 'r') as f:
        old_pch_lines = [x.strip() for x in f.readlines()]
        new_lines = generate_includes(groups)
        # Find the first include in the old pch.
        start = -1
        for i in xrange(len(old_pch_lines)):
            if old_pch_lines[i].startswith('#include'):
                start = i
                break
        # Clobber if there is a mismatch.
        if force_update or start < 0 or (len(old_pch_lines) - start < len(new_lines)):
            generate(new_lines, libname, header, module)
            return 0
        else:
            for i in xrange(len(new_lines)):
                if new_lines[i] != old_pch_lines[start + i]:
                    generate(new_lines, libname, header, module)
                    return 0
            else:
                # Identical, but see if new pch removed anything.
                for i in xrange(start + len(new_lines), len(old_pch_lines)):
                    if '#include' in old_pch_lines[i]:
                        generate(new_lines, libname, header, module)
                        return 0

    # Didn't update.
    return 1

if __name__ == '__main__':
    """ Process all the includes in a Module
        to make into a PCH file.
        Run without arguments for unittests,
        and to see usage.
    """

    if len(sys.argv) >= 3:
        status = main()
        sys.exit(status)

    print('Usage: {} <Module name> <Library name> [options]'.format(sys.argv[0]))
    print('    Always run from the root of LO repository.\n')
    print('    Options:')
    print('    --cutoff=<count> - Threshold to excluding headers.')
    print('    --exclude:<category> - Exclude category-specific headers.')
    print('    --include:<category> - Include category-specific headers.')
    print('    --force - Force updating the pch even when nothing changes.')
    print('    Categories:')
    print('         module - Headers in /inc directory of a module.')
    print('         local  - Headers local to a source file.')
    print('         system - Platform-specific headers.')
    print('    --silent - print only errors.')
    print('\nRunning unit-tests...')


class TestMethods(unittest.TestCase):

    def test_sanitize(self):
        self.assertEqual(sanitize('#include "blah/file.cxx"'),
                                '#include <blah/file.cxx>')
        self.assertEqual(sanitize('  #include\t"blah/file.cxx" '),
                                '#include <blah/file.cxx>')
        self.assertEqual(sanitize('  '),
                                '')

    def test_filter_ignore(self):
        self.assertEqual(filter_ignore('blah/file.cxx', 'mod'),
                                     '')
        self.assertEqual(filter_ignore('vector', 'mod'),
                                     'vector')
        self.assertEqual(filter_ignore('file.cxx', 'mod'),
                                     '')

    def test_remove_rare(self):
        self.assertEqual(remove_rare([]),
                                [])

class TestMakefileParser(unittest.TestCase):

    def setUp(self):
        global EXCLUDE_SYSTEM
        EXCLUDE_SYSTEM = False

    def test_parse_singleline_eval(self):
        source = "$(eval $(call gb_Library_Library,sal))"
        lines = source.split('\n')
        groups = {'':[]}
        groups = parse_makefile(groups, lines, 0, None, 0)
        self.assertEqual(len(groups), 1)
        self.assertEqual(len(groups['']), 0)

    def test_parse_multiline_eval(self):
        source = """$(eval $(call gb_Library_set_include,sal,\\
	$$(INCLUDE) \\
	-I$(SRCDIR)/sal/inc \\
))
"""
        lines = source.split('\n')
        groups = {'':[]}
        groups = parse_makefile(groups, lines, 0, None, 0)
        self.assertEqual(len(groups), 1)
        self.assertEqual(len(groups['']), 0)

    def test_parse_multiline_eval_with_if(self):
        source = """$(eval $(call gb_Library_add_defs,sal,\\
	$(if $(filter $(OS),IOS), \\
		-DNO_CHILD_PROCESSES \\
	) \\
))
"""
        lines = source.split('\n')
        groups = {'':[]}
        groups = parse_makefile(groups, lines, 0, None, 0)
        self.assertEqual(len(groups), 1)
        self.assertEqual(len(groups['']), 0)

    def test_parse_multiline_add_with_if(self):
        source = """$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/osl/unx/time \\
        $(if $(filter DESKTOP,$(BUILD_TYPE)), sal/osl/unx/salinit) \\
))
"""
        lines = source.split('\n')
        groups = {'':[]}
        groups = parse_makefile(groups, lines, 0, None, 0)
        self.assertEqual(len(groups), 1)
        self.assertEqual(len(groups['']), 1)
        self.assertEqual(groups[''][0], 'sal/osl/unx/time.cxx')

    def test_parse_if_else(self):
        source = """ifeq ($(OS),MACOSX)
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/osl/mac/mac \\
))
else
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/osl/unx/uunxapi \\
))
endif
"""
        lines = source.split('\n')
        groups = {'':[]}
        groups = parse_makefile(groups, lines, 0, None, 0)
        self.assertEqual(len(groups), 3)
        self.assertEqual(len(groups['']), 0)
        self.assertEqual(len(groups['MACOSX']), 1)
        self.assertEqual(len(groups['!MACOSX']), 1)
        self.assertEqual(groups['MACOSX'][0], 'sal/osl/mac/mac.cxx')
        self.assertEqual(groups['!MACOSX'][0], 'sal/osl/unx/uunxapi.cxx')

    def test_parse_nested_if(self):
        source = """ifeq ($(OS),MACOSX)
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/osl/mac/mac \\
))
else
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/osl/unx/uunxapi \\
))

ifeq ($(OS),LINUX)
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/textenc/context \\
))
endif
endif
"""
        lines = source.split('\n')
        groups = {'':[]}
        groups = parse_makefile(groups, lines, 0, None, 0)
        self.assertEqual(len(groups), 4)
        self.assertEqual(len(groups['']), 0)
        self.assertEqual(len(groups['MACOSX']), 1)
        self.assertEqual(len(groups['!MACOSX']), 1)
        self.assertEqual(len(groups['LINUX']), 1)
        self.assertEqual(groups['MACOSX'][0], 'sal/osl/mac/mac.cxx')
        self.assertEqual(groups['!MACOSX'][0], 'sal/osl/unx/uunxapi.cxx')
        self.assertEqual(groups['LINUX'][0], 'sal/textenc/context.cxx')

    def test_parse_exclude_system(self):
        source = """ifeq ($(OS),MACOSX)
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/osl/mac/mac \\
))
else
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/osl/unx/uunxapi \\
))

ifeq ($(OS),LINUX)
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/textenc/context \\
))
endif
endif
"""
        global EXCLUDE_SYSTEM
        EXCLUDE_SYSTEM = True

        lines = source.split('\n')
        groups = {'':[]}
        groups = parse_makefile(groups, lines, 0, None, 0)
        self.assertEqual(len(groups), 1)
        self.assertEqual(len(groups['']), 0)

    def test_parse_filter(self):
        source = """ifneq ($(filter $(OS),MACOSX IOS),)
$(eval $(call gb_Library_add_exception_objects,sal,\\
	sal/osl/unx/osxlocale \\
))
endif
"""
        # Filter is still unsupported.
        lines = source.split('\n')
        groups = {'':[]}
        groups = parse_makefile(groups, lines, 0, None, 0)
        self.assertEqual(len(groups), 1)
        self.assertEqual(len(groups['']), 0)

unittest.main()

# vim: set et sw=4 ts=4 expandtab: