# -*- mode: makefile; coding: utf-8 -*-
# Copyright © 2005-2010 Jonas Smedegaard <dr@jones.dk>
# Description: Check for changes to copyright notices in source
#
# 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, 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.

_cdbs_scripts_path ?= /usr/lib/cdbs
_cdbs_rules_path ?= /usr/share/cdbs/1/rules
_cdbs_class_path ?= /usr/share/cdbs/1/class

ifndef _cdbs_rules_copyright_check
_cdbs_rules_copyright_check := 1

include $(_cdbs_rules_path)/buildcore.mk$(_cdbs_makefile_suffix)

CDBS_BUILD_DEPENDS := $(CDBS_BUILD_DEPENDS), devscripts (>= 2.10.7)

# Set to yes to fail on changed/new hints are found
#DEB_COPYRIGHT_CHECK_STRICT = yes

# Single regular expression for files to include or ignore
DEB_COPYRIGHT_CHECK_REGEX ?= .*
#DEB_COPYRIGHT_CHECK_IGNORE_REGEX ?= ^\./(debian/.*|(.*/)?config\.(guess|sub|rpath)(\..*)?)$
DEB_COPYRIGHT_CHECK_IGNORE_REGEX ?= ^\./debian/(changelog|copyright(|_hints|_newhints))$

# number of lines from the top of each file to investigate
DEB_COPYRIGHT_CHECK_PARSELINES ?= 99999

DEB_COPYRIGHT_CHECK_SCRIPT ?= licensecheck
DEB_COPYRIGHT_CHECK_ARGS ?= -c '$(DEB_COPYRIGHT_CHECK_REGEX)' -r --copyright -i '$(DEB_COPYRIGHT_CHECK_IGNORE_REGEX)' -l '$(DEB_COPYRIGHT_CHECK_PARSELINES)' ./*
DEB_COPYRIGHT_CHECK_INVOKE ?= $(DEB_COPYRIGHT_CHECK_SCRIPT) $(DEB_COPYRIGHT_CHECK_ARGS)

pre-build:: debian/stamp-copyright-check

debian/stamp-copyright-check:
	@echo 'Scanning upstream source for new/changed copyright notices...'
	@echo $(DEB_COPYRIGHT_CHECK_INVOKE) \
		"| some-output-filtering..."

# Perl in shell in make requires extra care:
#  * Single-quoting ('...') protects against shell expansion
#  * Double-dollar ($$) expands to plain dollar ($) in make
	@$(DEB_COPYRIGHT_CHECK_INVOKE) \
		| LC_ALL=C perl -e \
	'print "Format-Specification: http://svn.debian.org/wsvn/dep/web/deps/dep5.mdwn?rev=135\n";'\
	'print "X-Draft: Autogenerated by CDBS snippet copyright-check.mk\n\n";'\
	'$$n=0; while (<>) {'\
	'	if (/^([^:\s][^:]+):[\s]+(\S.*?)\s*$$/) {'\
	'		$$files[$$n]{name}=$$1;'\
	'		$$files[$$n]{license}=$$2;'\
	'	};'\
	'	if (/^\s*\[Copyright:\s*(\S.*?)\s*\]/) {'\
	'		$$files[$$n]{copyright}=$$1;'\
	'	};'\
	'	/^$$/ and $$n++;'\
	'};'\
	'foreach $$file (@files) {'\
	'	$$file->{license} =~ s/\s*\(unversioned\/unknown version\)//;'\
	'	$$file->{license} =~ s/\s*\(with incorrect FSF address\)//;'\
	'	$$file->{license} =~ s/\s+\(v([^)]+) or later\)/-$$1+/;'\
	'	$$file->{license} =~ s/\s+\(v([^)]+)\)/-$$1/;'\
	'	$$file->{license} =~ s/\s*(\*No copyright\*)\s*// and $$file->{copyright} = $$1;'\
	'	$$file->{license} =~ s/^\s*(GENERATED FILE)/UNKNOWN/;'\
	'	$$file->{license} =~ s/\s+(GENERATED FILE)//;'\
	'	$$file->{copyright} =~ s/^&copy;\s*//;'\
	'	$$file->{copyright} =~ s/(?<=(\b\d{4}))(?{$$y=$$^N})\s*[,-]\s*((??{$$y+1}))\b/-$$2/g;'\
	'	$$file->{copyright} =~ s/(?<=\b\d{4})\s*-\s*\d{4}(?=\s*-\s*(\d{4})\b)//g;'\
	'	$$file->{copyright} =~ s/\b(\d{4}),?\s+([\S^\d])/$$1, $$2/g;'\
	'	my @ownerlines = grep {/\w\w/} split /\s\/\s/, $$file->{copyright};'\
	'	my @ownerlines_clean = ();'\
	'	my %owneryears = ();'\
	'	for $$ownerline ( @ownerlines ) {'\
	'		my ($$owneryear, $$owner) = $$ownerline =~ /^([\d-,\s]*)\s*+(.*)/;'\
	'		$$owner =~ s/^by\s+//;'\
	'		$$owner =~ s/,?\s+All Rights Reserved\.?//gi;'\
	'		push @ownerlines_clean, "$$owneryear$$owner";'\
	'		push @{ $$owneryears{"$$owner"} }, $$owneryear;'\
	'	};'\
	'	my @owners = sort keys %owneryears;'\
	'	my $$pattern = join ("\n", $$file->{license}, @owners);'\
	'	push @{ $$patternfiles{"$$pattern"} }, $$file->{name};'\
	'	push @{ $$patternownerlines{"$$pattern"} }, @ownerlines_clean;'\
	'	$$patternlicense{"$$pattern"} = $$file->{license};'\
	'};'\
	'foreach $$pattern ( sort {'\
	'			@{$$patternfiles{$$b}} <=> @{$$patternfiles{$$a}}'\
	'			||'\
	'			$$a cmp $$b'\
	'		} keys %patternfiles ) {'\
	'	my $$prev;'\
	'	@ownerlines_unique = grep($$_ ne $$prev && (($$prev) = $$_), sort @{ $$patternownerlines{$$pattern} });'\
	'	print "Files: ", join(",\n\t", sort @{ $$patternfiles{$$pattern} }), "\n";'\
	'	print "Copyright: ", join("\n\t", @ownerlines_unique), "\n";'\
	'	print "License: $$patternlicense{$$pattern}\n FIXME\n\n";'\
	'};'\
		> debian/copyright_newhints
	@patterncount="`cat debian/copyright_newhints | sed 's/^[^:]*://' | LANG=C sort -u | grep . -c -`"; \
		echo "Found $$patterncount different copyright and licensing combinations."
	@if [ ! -f debian/copyright_hints ]; then touch debian/copyright_hints; fi
	@newstrings=`diff -a -u debian/copyright_hints debian/copyright_newhints | sed '1,2d' | egrep -a '^\+' - | sed 's/^\+//'`; \
		if [ -n "$$newstrings" ]; then \
			echo "$(if $(DEB_COPYRIGHT_CHECK_STRICT),ERROR,WARNING): The following (and possibly more) new or changed notices discovered:"; \
			echo; \
			echo "$$newstrings" \
				| perl -ne '/^.{0,60}$$/ or s/^(.{0,60})\b.*$$/$$1…/;s/[^[:print:][:space:]…]//g;$$_ ne $$prev and (($$prev) = $$_) and print' \
				| sort -m \
				| head -n 200; \
			echo; \
			echo "To fix the situation please do the following:"; \
			echo "  1) Fully compare debian/copyright_hints with debian/copyright_newhints"; \
			echo "  2) Update debian/copyright as needed"; \
			echo "  3) Replace debian/copyright_hints with debian/copyright_newhints"; \
			$(if $(DEB_COPYRIGHT_CHECK_STRICT),exit 1,:); \
		else \
			echo 'No new copyright notices found - assuming no news is good news...'; \
			rm -f debian/copyright_newhints; \
		fi
	touch $@

clean::
	$(if $(DEB_COPYRIGHT_CHECK_STRICT),:,rm -f debian/copyright_newhints)
	rm -f debian/stamp-copyright-check

endif