#!/usr/bin/python

"""Copyright 2011 Gentoo Foundation
Distributed under the terms of the GNU General Public License v2
"""

from __future__ import print_function

"""
TODO:
- custom url handlers (portscout)
  - sourceforge: use rss feeds
- respect robots.txt (portscout)
- check other distros (youri)
- clean blacklist system
"""

# Meta:
__author__ = "Corentin Chary (iksaif)"
__email__ = "corentin.chary@gmail.com"
__version__ = "git"
__productname__ = "euscan"
__description__ = "A tool to detect new upstream releases."

# =======
# Imports
# =======

import os
import sys
import re
import time
import getopt
import errno
import random
import urllib2
import StringIO

import pkg_resources

import portage
from portage.output import white, yellow, turquoise, green, teal, red, EOutput
from portage.dbapi.porttree import _parse_uri_map

import gentoolkit.pprinter as pp
from gentoolkit import errors
from gentoolkit.query import Query
from gentoolkit.eclean.search import (port_settings)

# =======
# Globals
# =======

QUERY_OPTS = {"include_masked": True}

BLACKLIST_PACKAGES = ['sys-kernel/usermode-sources', 'sys-kernel/xbox-sources',
		      'sys-kernel/cell-sources', 'sys-libs/libstdc++-v3']

SCANDIR_BLACKLIST_URLS = ['mirror://rubygems/(.*)', 'mirror://gentoo/(.*)']

BRUTEFORCE_BLACKLIST_PACKAGES = ['dev-util/patchelf', 'net-zope/plonepopoll']
BRUTEFORCE_BLACKLIST_URLS = ['http://(.*)dockapps.org/download.php/id/(.*)']

# =========
# Functions
# =========

def cast_int_components(version):
        for i, obj in enumerate(version):
		try:
			version[i] = int(obj)
		except ValueError:
			pass
	return version

def parse_version(version):
	version = pkg_resources.parse_version(version)
	#version = list(version)
	#return cast_int_components(version)
	return version


def template_from_url(url, version):
	prefix, chunks = url.split('://')
	chunks = chunks.split('/')

	for i in range(len(chunks)):
		chunk = chunks[i]

		if not chunk:
			continue

		# If it's the full version, it's easy
		if version in chunk:
			chunk = chunk.replace(version, '${PV}')
		# For directories made from a part of the version
		elif version.startswith(chunk):
			full = split_version(version)
			part = split_version(chunk)

			for j in range(min(len(full), len(part))):

				if part[j] != full[j]:
					break
				part[j] = '${%d}' % j

			chunk = join_version(part)
			chunk = chunk.replace('}$', '}.$')

		chunks[i] = chunk

	return prefix + "://" + "/".join(chunks)

def url_from_template(url, version):
	components = split_version(version)

	url = url.replace('${PV}', version)
	for i in range(len(components)):
		url = url.replace('${%d}' % i, str(components[i]))

	return url

# Stolen from distutils.LooseVersion
# Used for brute force to increment the version
def split_version(version):
    component_re = re.compile(r'(\d+ | [a-z]+ | \.)', re.VERBOSE)
    components = filter(lambda x: x and x != '.', component_re.split(version))
    for i in range(len(components)):
            try:
		    components[i] = int(components[i])
            except ValueError:
		    pass
    return components

def join_version(components):
	version = ""
	for i in range(len(components)):
		version += str(components[i])
		if i >= len(components) - 1:
			break
		if type(components[i]) != str and type(components[i + 1]) != str:
			version += "."
	return version

def increment_version(components, level):
	n = len(components)

	if level > n - 1 or level < 0:
		raise Exception

	for i in range(n, level + 1, -1):
		if type(components[i - 1]) == int:
			components[i - 1] = 0

	if type(components[level]) == int:
		components[level] += 1

	return components

def gen_versions(components, level):
	n = len(components)
	depth = level
	level = min(level, n)

	if not n:
		return []

	versions = []

	for i in range(n, n - level, -1):
		increment_version(components, i - 1)
		for j in range(depth):
			versions.append(list(components))
			increment_version(components, i - 1)

	return versions

def tryurl(fileurl, output, regex):
	result = False

	output.ebegin("Trying: " + fileurl)

	try:
		basename = os.path.basename(fileurl)

		fp = urllib2.urlopen(fileurl, None, 5)
		headers = fp.info()

		if 'Content-disposition' in headers and basename not in headers['Content-disposition']:
			result = False
		elif 'Content-Length' in headers and headers['Content-Length'] == '0':
			result = False
		elif 'text/html' in headers['Content-Type']:
			result = False
		elif fp.geturl() != fileurl:
			basename2 = os.path.basename(fp.geturl())

			# Redirect to another (earlier?) version
			if basename != basename2 and re.match(regex, fp.geturl()):
				result = False
			else:
				result = True
		else:
			result = True
	except urllib2.URLError:
		result = False
	except IOError:
		result = False

	output.eend(errno.ENOENT if not result else 0)

	return result

def regex_from_template(template):
	template = re.escape(template)
	template = template.replace('\$\{', '${')
        template = template.replace('\}', '}')
        template = template.replace('}\.$', '}.$')
	template = re.sub(r'(\$\{\d+\}\.?)+', r'([\w\.\-]+?)', template)
	#template = re.sub(r'(\$\{\d+\}\.+)+', '(.+?)\.', template)
	#template = re.sub(r'(\$\{\d+\})+', '(.+?)', template)
	template = template.replace('${PV}', r'((\d+)((\.\d+)*)([a-zA-Z]?)(((-|_)(pre|p|beta|b|alpha|a|rc|r)\d*)*))')
	template = template + r'/?$'
	return template

def basedir_from_template(template):
	idx = template.find('${')
	if idx == -1:
		return template

	idx = template[0:idx].rfind('/')
	if idx == -1:
		return ""

	return template[0:idx]

def generate_scan_paths(url):
        prefix, chunks = url.split('://')
        chunks = chunks.split('/')

        steps = []

	path = prefix + ":/"
        for chunk in chunks:
                if '${' in chunk:
                        steps.append((path, regex_from_template(chunk)))
			path = ""
		else:
			path += "/"
			path += chunk
        return steps

def scan_directory_recursive(url, steps, vmin, vmax, output):
	if not steps:
		return []

	url += steps[0][0]
	pattern = steps[0][1]

	steps = steps[1:]

	output.einfo("Scanning: %s" % url)

	try:
		fp = urllib2.urlopen(url, None, 5)
	except urllib2.URLError:
		return []
	except IOError:
		return []

	data = fp.read()

	results = []

	if re.search("<\s*a\s+[^>]*href", data):
		from BeautifulSoup import BeautifulSoup

		soup = BeautifulSoup(data)

		for link in soup.findAll('a'):
			href = link.get("href")
			if not href:
				continue
			if href.startswith(url):
				href = href.replace(url, "", 1)

			match = re.match(pattern, href, re.I)
			if match:
				results.append((match.group(1), match.group(0)))

	elif url.startswith('ftp://'): # Probably a FTP Server
		buf = StringIO.StringIO(data)
		for line in buf.readlines():
			line = line.replace("\n", "").replace("\r", "")
			match = re.search(pattern, line, re.I)
			if match:
				results.append((match.group(1), match.group(0)))
		# add url

	versions = []

	for version, path in results:
		ver = parse_version(version)

		if vmin and ver <= vmin:
			continue
		if vmax and ver >= vmax:
			continue

		# Try to skip nightly builds when not wanted (www-apps/moodle)
		if len(vmin) != len(ver) and len(ver) == 2 and len(ver[0]) == len('yyyymmdd'):
			continue

		if not url.endswith('/') and not path.startswith('/'):
			path = url + '/' + path
		else:
			path = url + path

		versions.append((path, version))
		if steps:
			ret = scan_directory_recursive(path, steps, vmin, vmax, output)
			versions.extend(ret)
	return versions

def scan_directory(cpv, fileurl, options, output, limit=None):
	# Ftp: list dir
	# Handle mirrors
	if not options["scan-dir"]:
		return []

	catpkg, ver, rev = portage.pkgsplit(cpv)

	template = template_from_url(fileurl, ver)
	if '${' not in template:
		output.einfo("Url doesn't seems to depend on version: %s not found in %s"
			     % (ver, fileurl))
		return []
	else:
		output.einfo("Scanning: %s" % template)

	vmin = parse_version(ver)

	steps = generate_scan_paths(template)
	return scan_directory_recursive("", steps, vmin, limit, output)

def brute_force(cpv, fileurl, options, output, limit=None):
	if options["brute-force"] <= 0:
		return []

	catpkg, ver, rev = portage.pkgsplit(cpv)

	for bp in BRUTEFORCE_BLACKLIST_PACKAGES:
		if re.match(bp, catpkg):
			output.einfo("%s is blacklisted by rule %s" % (catpkg, bp))
			return []

	for bp in BRUTEFORCE_BLACKLIST_URLS:
		if re.match(bp, fileurl):
			output.einfo("%s is blacklisted by rule %s" % (catpkg, bp))
			return []

	components = split_version(ver)
	versions = gen_versions(components, options["brute-force"])

	output.einfo("Generating version from " + ver)

	if not versions:
		output.einfo("Can't generate new versions from " + ver)
		return []

	template = template_from_url(fileurl, ver)

	if '${PV}' not in template:
		output.einfo("Url doesn't seems to depend on full version: %s not found in %s"
			     % (ver, fileurl))
		return []
	else:
		output.einfo("Brute forcing: %s" % template)

	result = []

	i = 0
	done = []

	while i < len(versions):
		components = versions[i]
		i += 1
		if components in done:
			continue
		done.append(tuple(components))

		vstring = join_version(components)
		version = parse_version(vstring)

		if limit and version >= limit:
			continue

		url = url_from_template(template, vstring)
		regex = regex_from_template(template)

		if not tryurl(url, output, regex):
			continue

		result.append([url, vstring])

		if options["brute-force-recursive"]:
			for v in gen_versions(components, options["brute-force"]):
				if v not in versions and tuple(v) not in done:
					versions.append(v)

		if options["oneshot"]:
			break

	return result


def parseMirror(uri, output):
	from random import shuffle

	mirrors = portage.settings.thirdpartymirrors()

	if not uri.startswith("mirror://"):
		return uri

	eidx = uri.find("/", 9)
	if eidx == -1:
		output.einfo("Invalid mirror definition in SRC_URI:\n")
		output.einfo("  %s\n" % (uri))
		return None

	mirrorname = uri[9:eidx]
	path = uri[eidx+1:]

	if mirrorname in mirrors:
		mirrors = mirrors[mirrorname]
		shuffle(mirrors)
		uri = mirrors[0].strip("/") + "/" + path
	else:
		output.einfo("No known mirror by the name: %s\n" % (mirrorname))
		return None

        return uri

def setupSignals():
    """ This block ensures that ^C interrupts are handled quietly. """
    import signal

    def exithandler(signum,frame):
        signal.signal(signal.SIGINT, signal.SIG_IGN)
        signal.signal(signal.SIGTERM, signal.SIG_IGN)
	print ()
	sys.exit(errno.EINTR)

    signal.signal(signal.SIGINT, exithandler)
    signal.signal(signal.SIGTERM, exithandler)
    signal.signal(signal.SIGPIPE, signal.SIG_DFL)


def printVersion():
	"""Output the version info."""
	print( "%s (%s) - %s" \
			% (__productname__, __version__, __description__))
	print()
	print("Author: %s <%s>" % (__author__,__email__))
	print("Copyright 2011 Gentoo Foundation")
	print("Distributed under the terms of the GNU General Public License v2")


def printUsage(_error=None, help=None):
	"""Print help message. May also print partial help to stderr if an
	error from {'options'} is specified."""

	out = sys.stdout
	if _error:
		out = sys.stderr
	if not _error in ('global-options', 'packages',):
		_error = None
	if not _error and not help: help = 'all'
	if _error in ('global-options',):
		print( pp.error("Wrong option on command line."), file=out)
		print( file=out)
	if _error in ('packages',):
		print( pp.error("You need to specify exactly one package."), file=out)
		print( file=out)
	print( white("Usage:"), file=out)
	if _error in ('global-options', 'packages',) or help == 'all':
		print( " "+turquoise(__productname__),
			yellow("[options]"),
			green("<package>"), file=out)
	if _error in ('global-options',) or help == 'all':
	   	print( " "+turquoise(__productname__),
	   	        yellow("[--help, --version]"), file=out)

	print(file=out)
	if _error in ('global-options',) or help:
		print( "Available ", yellow("options")+":", file=out)
		print( yellow(" -C, --nocolor")+
			"             - turn off colors on output", file=out)
		print( yellow(" -q, --quiet")+
			"               - be as quiet as possible", file=out)
		print( yellow(" -h, --help")+ \
			"                - display the help screen", file=out)
		print( yellow(" -V, --version")+
			"             - display version info", file=out)
		print( file=out)
		print( yellow(" -1, --oneshot")+
			"             - stop as soon as a new version is found", file=out)
		print( yellow(" -b, --brute-force=<level>")+
			" - define the brute force "+yellow("<level>")+" (default: 2)\n" +
			" " * 29  + "bigger levels will generate more versions numbers\n" +
			" " * 29  + "0 means disabled", file=out)
		print( file=out)
 	if _error in ('packages',) or help:
		print( green(" package")+
			"                   - the package (or ebuild) you want to scan", file=out)
		print( file=out)
	#print( "More detailed instruction can be found in",
	#		turquoise("`man %s`" % __productname__), file=out)


class ParseArgsException(Exception):
	"""For parseArgs() -> main() communications."""
	def __init__(self, value):
		self.value = value # sdfgsdfsdfsd
	def __str__(self):
		return repr(self.value)


def parseArgs(options={}):
	"""Parse the command line arguments. Raise exceptions on
	errors. Returns package and affect the options dict.
	"""

	def optionSwitch(option,opts):
		"""local function for interpreting command line options
		and setting options accordingly"""
		return_code = True
		for o, a in opts:
			if o in ("-h", "--help"):
			   	raise ParseArgsException('help')
			elif o in ("-V", "--version"):
				raise ParseArgsException('version')
			elif o in ("-C", "--nocolor"):
				options['nocolor'] = True
				pp.output.nocolor()
			elif o in ("-q", "--quiet"):
				options['quiet'] = True
				options['verbose'] = False
			elif o in ("-1", "--oneshot"):
				options['oneshot'] = True
			elif o in ("-b", "--brute-force"):
				options['brute-force'] = int(a)
			elif o in ("-v", "--verbose") and not options['quiet']:
					options['verbose'] = True
			else:
				return_code = False

		return return_code

	# here are the different allowed command line options (getopt args)
	getopt_options = {'short':{}, 'long':{}}
	getopt_options['short']['global'] = "hVCqv1b:"
	getopt_options['long']['global'] = ["help", "version", "nocolor", "quiet",
					    "verbose", "oneshot", "brute-force="]
	# set default options, except 'nocolor', which is set in main()
	options['quiet'] = False
	options['verbose'] = False
	options['brute-force'] = 2
	options['oneshot'] = False
	options['brute-force-recursive'] = True # FIXME add an option
	options['scan-dir'] = True # FIXME add an option

	short_opts = getopt_options['short']['global']
	long_opts = getopt_options['long']['global']
	opts_mode = 'global'

	# apply getopts to command line, show partial help on failure
	try:
		opts, args = getopt.getopt(sys.argv[1:], short_opts, long_opts)
	except:
		raise ParseArgsException(opts_mode+'-options')

	# set options accordingly
	optionSwitch(options,opts)

	if len(args) != 1:
	   	raise ParseArgsException('packages')

	return args[0]


def scanUpstream(options, package, output):
        matches = Query(package).find(
                include_masked=QUERY_OPTS['include_masked'],
                in_installed=False
        )

        if not matches:
                sys.stderr.write(pp.warn("No package matching '%s'" % pp.pkgquery(package)))
                sys.exit(errno.ENOENT)

	matches = sorted(matches)
        pkg = matches.pop()

	if pkg.version == '9999':
		if len(matches) == 0:
			sys.stderr.write(pp.warn("Package '%s' only have a dev version (9999)" % pp.pkgquery(package)))
			sys.exit(errno.ENOENT)
		else:
			pkg = matches.pop()

	if pkg.cp in BLACKLIST_PACKAGES:
		sys.stderr.write(pp.warn("Package '%s' is blacklisted" % pp.pkgquery(package)))
		sys.exit(errno.ENOENT)

        pp.uprint(" * %s [%s]" % (pp.cpv(pkg.cpv), pp.section(pkg.repo_name())))
	pp.uprint()

        ebuild_path = pkg.ebuild_path()
        if ebuild_path:
                pp.uprint('Ebuild: ' + pp.path(os.path.normpath(ebuild_path)))

        pp.uprint('Repository: ' + pkg.repo_name())
        pp.uprint('Homepage: ' + pkg.environment("HOMEPAGE"))
        pp.uprint('Description: ' + pkg.environment("DESCRIPTION"))
	pp.uprint()

	cpv = pkg.cpv
	metadata = {
		"EAPI"    : port_settings["EAPI"],
		"SRC_URI" : pkg.environment("SRC_URI", False),
	}
	use = frozenset(port_settings["PORTAGE_USE"].split())
	try:
		alist = _parse_uri_map(cpv, metadata, use=use)
		aalist = _parse_uri_map(cpv, metadata)
	except InvalidDependString as e:
                sys.stderr.write(pp.warn("%s\n" % str(e)))
                sys.stderr.write(pp.warn("Invalid SRC_URI for '%s'" % pp.pkgquery(cpv)))
                sys.exit(errno.ENOENT)

	if "mirror" in portage.settings.features:
		fetchme = aalist
	else:
		fetchme = alist

	versions = []

	for filename in fetchme:
		for fileurl in fetchme[filename]:
			skipscan = False

			output.einfo("SRC_URI is '%s'" % fileurl)

			if '://' not in fileurl:
				output.einfo("Invalid url '%s'" % fileurl)
				continue

			for bp in SCANDIR_BLACKLIST_URLS:
				if re.match(bp, fileurl):
					output.einfo("%s is blacklisted by rule %s" % (fileurl, bp))
					skipscan = True

                        url = parseMirror(fileurl, output)

			# Try list dir, but not for gentoo mirrors, it's too slow
			if not skipscan:
				versions.extend(scan_directory(cpv, url, options, output))

			if versions and options['oneshot']:
				break

			# Try manual bump
			versions.extend(brute_force(cpv, url, options, output))

			if versions and options['oneshot']:
				break

	newversions = {}

	for url, version in versions:
		if version in newversions and len(url) < len(newversions[version]):
			continue
		newversions[version] = url

	print ()

	for version in newversions:
		print ("Upstream Version: " + pp.number("%s" % version) + pp.path(" %s" % newversions[version]))
	if not len(newversions):
		print (pp.warn("Didn't find any new version, check package's homepage for " +
			       "more informations"));
	return versions


def main():
	"""Parse command line and execute all actions."""
	# set default options
	options = {}
	options['nocolor'] = (port_settings["NOCOLOR"] in ('yes','true')
		or not sys.stdout.isatty())
	if options['nocolor']:
		pp.output.nocolor()
	# parse command line options and actions
	try:
		package = parseArgs(options)
	# filter exception to know what message to display
	except ParseArgsException as e:
		if e.value == 'help':
			printUsage(help='all')
			sys.exit(0)
		elif e.value[:5] == 'help-':
			printUsage(help=e.value[5:])
			sys.exit(0)
		elif e.value == 'version':
			printVersion()
			sys.exit(0)
		else:
			printUsage(e.value)
			sys.exit(errno.EINVAL)

	output = EOutput(options['quiet'])
	scanUpstream(options, package, output)


if __name__ == "__main__":
	try:
                setupSignals()
		main()
	except KeyboardInterrupt:
		print( "Aborted.")
		sys.exit(errno.EINTR)
	sys.exit(0)