# Copyright 1999-2012 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

import errno
import io
import re
import warnings

import portage
portage.proxy.lazyimport.lazyimport(globals(),
	'portage.checksum:hashfunc_map,perform_multiple_checksums,' + \
		'verify_all,_filter_unaccelarated_hashes',
	'portage.util:write_atomic',
)

from portage import os
from portage import _encodings
from portage import _unicode_decode
from portage import _unicode_encode
from portage.exception import DigestException, FileNotFound, \
	InvalidDataType, MissingParameter, PermissionDenied, \
	PortageException, PortagePackageException
from portage.const import (MANIFEST1_HASH_FUNCTIONS, MANIFEST2_HASH_DEFAULTS,
	MANIFEST2_HASH_FUNCTIONS, MANIFEST2_IDENTIFIERS, MANIFEST2_REQUIRED_HASH)
from portage.localization import _

# Characters prohibited by repoman's file.name check.
_prohibited_filename_chars_re = re.compile(r'[^a-zA-Z0-9._\-+:]')

class FileNotInManifestException(PortageException):
	pass

def manifest2AuxfileFilter(filename):
	filename = filename.strip(os.sep)
	mysplit = filename.split(os.path.sep)
	if "CVS" in mysplit:
		return False
	for x in mysplit:
		if x[:1] == '.':
			return False
		if _prohibited_filename_chars_re.search(x) is not None:
			return False
	return not filename[:7] == 'digest-'

def manifest2MiscfileFilter(filename):
	filename = filename.strip(os.sep)
	if _prohibited_filename_chars_re.search(filename) is not None:
		return False
	return not (filename in ["CVS", ".svn", "files", "Manifest"] or filename.endswith(".ebuild"))

def guessManifestFileType(filename):
	""" Perform a best effort guess of which type the given filename is, avoid using this if possible """
	if filename.startswith("files" + os.sep + "digest-"):
		return None
	if filename.startswith("files" + os.sep):
		return "AUX"
	elif filename.endswith(".ebuild"):
		return "EBUILD"
	elif filename in ["ChangeLog", "metadata.xml"]:
		return "MISC"
	else:
		return "DIST"

def guessThinManifestFileType(filename):
	type = guessManifestFileType(filename)
	if type != "DIST":
		return None
	return "DIST"

def parseManifest2(mysplit):
	myentry = None
	if len(mysplit) > 4 and mysplit[0] in MANIFEST2_IDENTIFIERS:
		mytype = mysplit[0]
		myname = mysplit[1]
		try:
			mysize = int(mysplit[2])
		except ValueError:
			return None
		myhashes = dict(zip(mysplit[3::2], mysplit[4::2]))
		myhashes["size"] = mysize
		myentry = Manifest2Entry(type=mytype, name=myname, hashes=myhashes)
	return myentry

class ManifestEntry(object):
	__slots__ = ("type", "name", "hashes")
	def __init__(self, **kwargs):
		for k, v in kwargs.items():
			setattr(self, k, v)

class Manifest2Entry(ManifestEntry):
	def __str__(self):
		myline = " ".join([self.type, self.name, str(self.hashes["size"])])
		myhashkeys = list(self.hashes)
		myhashkeys.remove("size")
		myhashkeys.sort()
		for h in myhashkeys:
			myline += " " + h + " " + str(self.hashes[h])
		return myline

	def __eq__(self, other):
		if not isinstance(other, Manifest2Entry) or \
			self.type != other.type or \
			self.name != other.name or \
			self.hashes != other.hashes:
			return False
		return True

	def __ne__(self, other):
		return not self.__eq__(other)

class Manifest(object):
	parsers = (parseManifest2,)
	def __init__(self, pkgdir, distdir, fetchlist_dict=None,
		manifest1_compat=DeprecationWarning, from_scratch=False, thin=False,
			allow_missing=False, allow_create=True, hashes=None):
		""" Create new Manifest instance for package in pkgdir.
		    Do not parse Manifest file if from_scratch == True (only for internal use)
			The fetchlist_dict parameter is required only for generation of
			a Manifest (not needed for parsing and checking sums).
			If thin is specified, then the manifest carries only info for
			distfiles."""

		if manifest1_compat is not DeprecationWarning:
			warnings.warn("The manifest1_compat parameter of the "
				"portage.manifest.Manifest constructor is deprecated.",
				DeprecationWarning, stacklevel=2)

		self.pkgdir = _unicode_decode(pkgdir).rstrip(os.sep) + os.sep
		self.fhashdict = {}
		self.hashes = set()

		if hashes is None:
			hashes = MANIFEST2_HASH_DEFAULTS

		self.hashes.update(hashes.intersection(MANIFEST2_HASH_FUNCTIONS))
		self.hashes.difference_update(hashname for hashname in \
			list(self.hashes) if hashname not in hashfunc_map)
		self.hashes.add("size")
		self.hashes.add(MANIFEST2_REQUIRED_HASH)
		for t in MANIFEST2_IDENTIFIERS:
			self.fhashdict[t] = {}
		if not from_scratch:
			self._read()
		if fetchlist_dict != None:
			self.fetchlist_dict = fetchlist_dict
		else:
			self.fetchlist_dict = {}
		self.distdir = distdir
		self.thin = thin
		if thin:
			self.guessType = guessThinManifestFileType
		else:
			self.guessType = guessManifestFileType
		self.allow_missing = allow_missing
		self.allow_create = allow_create

	def getFullname(self):
		""" Returns the absolute path to the Manifest file for this instance """
		return os.path.join(self.pkgdir, "Manifest")
	
	def getDigests(self):
		""" Compability function for old digest/manifest code, returns dict of filename:{hashfunction:hashvalue} """
		rval = {}
		for t in MANIFEST2_IDENTIFIERS:
			rval.update(self.fhashdict[t])
		return rval
	
	def getTypeDigests(self, ftype):
		""" Similar to getDigests(), but restricted to files of the given type. """
		return self.fhashdict[ftype]

	def _readManifest(self, file_path, myhashdict=None, **kwargs):
		"""Parse a manifest.  If myhashdict is given then data will be added too it.
		   Otherwise, a new dict will be created and returned."""
		try:
			fd = io.open(_unicode_encode(file_path,
				encoding=_encodings['fs'], errors='strict'), mode='r',
				encoding=_encodings['repo.content'], errors='replace')
			if myhashdict is None:
				myhashdict = {}
			self._parseDigests(fd, myhashdict=myhashdict, **kwargs)
			fd.close()
			return myhashdict
		except (OSError, IOError) as e:
			if e.errno == errno.ENOENT:
				raise FileNotFound(file_path)
			else:
				raise

	def _read(self):
		""" Parse Manifest file for this instance """
		try:
			self._readManifest(self.getFullname(), myhashdict=self.fhashdict)
		except FileNotFound:
			pass

	def _parseManifestLines(self, mylines):
		"""Parse manifest lines and return a list of manifest entries."""
		for myline in mylines:
			myentry = None
			mysplit = myline.split()
			for parser in self.parsers:
				myentry = parser(mysplit)
				if myentry is not None:
					yield myentry
					break # go to the next line

	def _parseDigests(self, mylines, myhashdict=None, mytype=None):
		"""Parse manifest entries and store the data in myhashdict.  If mytype
		is specified, it will override the type for all parsed entries."""
		if myhashdict is None:
			myhashdict = {}
		for myentry in self._parseManifestLines(mylines):
			if mytype is None:
				myentry_type = myentry.type
			else:
				myentry_type = mytype
			myhashdict.setdefault(myentry_type, {})
			myhashdict[myentry_type].setdefault(myentry.name, {})
			myhashdict[myentry_type][myentry.name].update(myentry.hashes)
		return myhashdict

	def _getDigestData(self, distlist):
		"""create a hash dict for a specific list of files"""
		myhashdict = {}
		for myname in distlist:
			for mytype in self.fhashdict:
				if myname in self.fhashdict[mytype]:
					myhashdict.setdefault(mytype, {})
					myhashdict[mytype].setdefault(myname, {})
					myhashdict[mytype][myname].update(self.fhashdict[mytype][myname])
		return myhashdict

	def _createManifestEntries(self):
		valid_hashes = set(MANIFEST2_HASH_FUNCTIONS)
		valid_hashes.add('size')
		mytypes = list(self.fhashdict)
		mytypes.sort()
		for t in mytypes:
			myfiles = list(self.fhashdict[t])
			myfiles.sort()
			for f in myfiles:
				myentry = Manifest2Entry(
					type=t, name=f, hashes=self.fhashdict[t][f].copy())
				for h in list(myentry.hashes):
					if h not in valid_hashes:
						del myentry.hashes[h]
				yield myentry

	def checkIntegrity(self):
		for t in self.fhashdict:
			for f in self.fhashdict[t]:
				if MANIFEST2_REQUIRED_HASH not in self.fhashdict[t][f]:
					raise MissingParameter(_("Missing %s checksum: %s %s") %
						(MANIFEST2_REQUIRED_HASH, t, f))

	def write(self, sign=False, force=False):
		""" Write Manifest instance to disk, optionally signing it """
		if not self.allow_create:
			return
		self.checkIntegrity()
		try:
			myentries = list(self._createManifestEntries())
			update_manifest = True
			if myentries and not force:
				try:
					f = io.open(_unicode_encode(self.getFullname(),
						encoding=_encodings['fs'], errors='strict'),
						mode='r', encoding=_encodings['repo.content'],
						errors='replace')
					oldentries = list(self._parseManifestLines(f))
					f.close()
					if len(oldentries) == len(myentries):
						update_manifest = False
						for i in range(len(oldentries)):
							if oldentries[i] != myentries[i]:
								update_manifest = True
								break
				except (IOError, OSError) as e:
					if e.errno == errno.ENOENT:
						pass
					else:
						raise

			if update_manifest:
				if myentries or not (self.thin or self.allow_missing):
					# If myentries is empty, don't write an empty manifest
					# when thin or allow_missing is enabled. Except for
					# thin manifests with no DIST entries, myentries is
					# non-empty for all currently known use cases.
					write_atomic(self.getFullname(), "".join("%s\n" %
						str(myentry) for myentry in myentries))
				else:
					# With thin manifest, there's no need to have
					# a Manifest file if there are no DIST entries.
					try:
						os.unlink(self.getFullname())
					except OSError as e:
						if e.errno != errno.ENOENT:
							raise

			if sign:
				self.sign()
		except (IOError, OSError) as e:
			if e.errno == errno.EACCES:
				raise PermissionDenied(str(e))
			raise

	def sign(self):
		""" Sign the Manifest """
		raise NotImplementedError()
	
	def validateSignature(self):
		""" Validate signature on Manifest """
		raise NotImplementedError()
	
	def addFile(self, ftype, fname, hashdict=None, ignoreMissing=False):
		""" Add entry to Manifest optionally using hashdict to avoid recalculation of hashes """
		if ftype == "AUX" and not fname.startswith("files/"):
			fname = os.path.join("files", fname)
		if not os.path.exists(self.pkgdir+fname) and not ignoreMissing:
			raise FileNotFound(fname)
		if not ftype in MANIFEST2_IDENTIFIERS:
			raise InvalidDataType(ftype)
		if ftype == "AUX" and fname.startswith("files"):
			fname = fname[6:]
		self.fhashdict[ftype][fname] = {}
		if hashdict != None:
			self.fhashdict[ftype][fname].update(hashdict)
		if not MANIFEST2_REQUIRED_HASH in self.fhashdict[ftype][fname]:
			self.updateFileHashes(ftype, fname, checkExisting=False, ignoreMissing=ignoreMissing)
	
	def removeFile(self, ftype, fname):
		""" Remove given entry from Manifest """
		del self.fhashdict[ftype][fname]
	
	def hasFile(self, ftype, fname):
		""" Return whether the Manifest contains an entry for the given type,filename pair """
		return (fname in self.fhashdict[ftype])
	
	def findFile(self, fname):
		""" Return entrytype of the given file if present in Manifest or None if not present """
		for t in MANIFEST2_IDENTIFIERS:
			if fname in self.fhashdict[t]:
				return t
		return None
	
	def create(self, checkExisting=False, assumeDistHashesSometimes=False,
		assumeDistHashesAlways=False, requiredDistfiles=[]):
		""" Recreate this Manifest from scratch.  This will not use any
		existing checksums unless assumeDistHashesSometimes or
		assumeDistHashesAlways is true (assumeDistHashesSometimes will only
		cause DIST checksums to be reused if the file doesn't exist in
		DISTDIR).  The requiredDistfiles parameter specifies a list of
		distfiles to raise a FileNotFound exception for (if no file or existing
		checksums are available), and defaults to all distfiles when not
		specified."""
		if not self.allow_create:
			return
		if checkExisting:
			self.checkAllHashes()
		if assumeDistHashesSometimes or assumeDistHashesAlways:
			distfilehashes = self.fhashdict["DIST"]
		else:
			distfilehashes = {}
		self.__init__(self.pkgdir, self.distdir,
			fetchlist_dict=self.fetchlist_dict, from_scratch=True,
			thin=self.thin, allow_missing=self.allow_missing,
			allow_create=self.allow_create, hashes=self.hashes)
		pn = os.path.basename(self.pkgdir.rstrip(os.path.sep))
		cat = self._pkgdir_category()

		pkgdir = self.pkgdir
		if self.thin:
			cpvlist = self._update_thin_pkgdir(cat, pn, pkgdir)
		else:
			cpvlist = self._update_thick_pkgdir(cat, pn, pkgdir)

		distlist = set()
		for cpv in cpvlist:
			distlist.update(self._getCpvDistfiles(cpv))

		if requiredDistfiles is None:
			# This allows us to force removal of stale digests for the
			# ebuild --force digest option (no distfiles are required).
			requiredDistfiles = set()
		elif len(requiredDistfiles) == 0:
			# repoman passes in an empty list, which implies that all distfiles
			# are required.
			requiredDistfiles = distlist.copy()
		required_hash_types = set()
		required_hash_types.add("size")
		required_hash_types.add(MANIFEST2_REQUIRED_HASH)
		for f in distlist:
			fname = os.path.join(self.distdir, f)
			mystat = None
			try:
				mystat = os.stat(fname)
			except OSError:
				pass
			if f in distfilehashes and \
				not required_hash_types.difference(distfilehashes[f]) and \
				((assumeDistHashesSometimes and mystat is None) or \
				(assumeDistHashesAlways and mystat is None) or \
				(assumeDistHashesAlways and mystat is not None and \
				set(distfilehashes[f]) == set(self.hashes) and \
				distfilehashes[f]["size"] == mystat.st_size)):
				self.fhashdict["DIST"][f] = distfilehashes[f]
			else:
				try:
					self.fhashdict["DIST"][f] = perform_multiple_checksums(fname, self.hashes)
				except FileNotFound:
					if f in requiredDistfiles:
						raise

	def _is_cpv(self, cat, pn, filename):
		if not filename.endswith(".ebuild"):
			return None
		pf = filename[:-7]
		ps = portage.versions._pkgsplit(pf)
		cpv = "%s/%s" % (cat, pf)
		if not ps:
			raise PortagePackageException(
				_("Invalid package name: '%s'") % cpv)
		if ps[0] != pn:
			raise PortagePackageException(
				_("Package name does not "
				"match directory name: '%s'") % cpv)
		return cpv

	def _update_thin_pkgdir(self, cat, pn, pkgdir):
		for pkgdir, pkgdir_dirs, pkgdir_files in os.walk(pkgdir):
			break
		cpvlist = []
		for f in pkgdir_files:
			try:
				f = _unicode_decode(f,
					encoding=_encodings['fs'], errors='strict')
			except UnicodeDecodeError:
				continue
			if f[:1] == '.':
				continue
			pf = self._is_cpv(cat, pn, f)
			if pf is not None:
				cpvlist.append(pf)
		return cpvlist

	def _update_thick_pkgdir(self, cat, pn, pkgdir):
		cpvlist = []
		for pkgdir, pkgdir_dirs, pkgdir_files in os.walk(pkgdir):
			break
		for f in pkgdir_files:
			try:
				f = _unicode_decode(f,
					encoding=_encodings['fs'], errors='strict')
			except UnicodeDecodeError:
				continue
			if f[:1] == ".":
				continue
			pf = self._is_cpv(cat, pn, f)
			if pf is not None:
				mytype = "EBUILD"
				cpvlist.append(pf)
			elif manifest2MiscfileFilter(f):
				mytype = "MISC"
			else:
				continue
			self.fhashdict[mytype][f] = perform_multiple_checksums(self.pkgdir+f, self.hashes)
		recursive_files = []

		pkgdir = self.pkgdir
		cut_len = len(os.path.join(pkgdir, "files") + os.sep)
		for parentdir, dirs, files in os.walk(os.path.join(pkgdir, "files")):
			for f in files:
				try:
					f = _unicode_decode(f,
						encoding=_encodings['fs'], errors='strict')
				except UnicodeDecodeError:
					continue
				full_path = os.path.join(parentdir, f)
				recursive_files.append(full_path[cut_len:])
		for f in recursive_files:
			if not manifest2AuxfileFilter(f):
				continue
			self.fhashdict["AUX"][f] = perform_multiple_checksums(
				os.path.join(self.pkgdir, "files", f.lstrip(os.sep)), self.hashes)
		return cpvlist

	def _pkgdir_category(self):
		return self.pkgdir.rstrip(os.sep).split(os.sep)[-2]

	def _getAbsname(self, ftype, fname):
		if ftype == "DIST":
			absname = os.path.join(self.distdir, fname)
		elif ftype == "AUX":
			absname = os.path.join(self.pkgdir, "files", fname)
		else:
			absname = os.path.join(self.pkgdir, fname)
		return absname	
	
	def checkAllHashes(self, ignoreMissingFiles=False):
		for t in MANIFEST2_IDENTIFIERS:
			self.checkTypeHashes(t, ignoreMissingFiles=ignoreMissingFiles)
	
	def checkTypeHashes(self, idtype, ignoreMissingFiles=False):
		for f in self.fhashdict[idtype]:
			self.checkFileHashes(idtype, f, ignoreMissing=ignoreMissingFiles)
	
	def checkFileHashes(self, ftype, fname, ignoreMissing=False):
		try:
			ok, reason = verify_all(self._getAbsname(ftype, fname),
				_filter_unaccelarated_hashes(self.fhashdict[ftype][fname]))
			if not ok:
				raise DigestException(tuple([self._getAbsname(ftype, fname)]+list(reason)))
			return ok, reason
		except FileNotFound as e:
			if not ignoreMissing:
				raise
			return False, _("File Not Found: '%s'") % str(e)

	def checkCpvHashes(self, cpv, checkDistfiles=True, onlyDistfiles=False, checkMiscfiles=False):
		""" check the hashes for all files associated to the given cpv, include all
		AUX files and optionally all MISC files. """
		if not onlyDistfiles:
			self.checkTypeHashes("AUX", ignoreMissingFiles=False)
			if checkMiscfiles:
				self.checkTypeHashes("MISC", ignoreMissingFiles=False)
			ebuildname = "%s.ebuild" % self._catsplit(cpv)[1]
			self.checkFileHashes("EBUILD", ebuildname, ignoreMissing=False)
		if checkDistfiles or onlyDistfiles:
			for f in self._getCpvDistfiles(cpv):
				self.checkFileHashes("DIST", f, ignoreMissing=False)
	
	def _getCpvDistfiles(self, cpv):
		""" Get a list of all DIST files associated to the given cpv """
		return self.fetchlist_dict[cpv]

	def getDistfilesSize(self, fetchlist):
		total_bytes = 0
		for f in fetchlist:
			total_bytes += int(self.fhashdict["DIST"][f]["size"])
		return total_bytes

	def updateFileHashes(self, ftype, fname, checkExisting=True, ignoreMissing=True, reuseExisting=False):
		""" Regenerate hashes for the given file """
		if checkExisting:
			self.checkFileHashes(ftype, fname, ignoreMissing=ignoreMissing)
		if not ignoreMissing and fname not in self.fhashdict[ftype]:
			raise FileNotInManifestException(fname)
		if fname not in self.fhashdict[ftype]:
			self.fhashdict[ftype][fname] = {}
		myhashkeys = list(self.hashes)
		if reuseExisting:
			for k in [h for h in self.fhashdict[ftype][fname] if h in myhashkeys]:
				myhashkeys.remove(k)
		myhashes = perform_multiple_checksums(self._getAbsname(ftype, fname), myhashkeys)
		self.fhashdict[ftype][fname].update(myhashes)
	
	def updateTypeHashes(self, idtype, checkExisting=False, ignoreMissingFiles=True):
		""" Regenerate all hashes for all files of the given type """
		for fname in self.fhashdict[idtype]:
			self.updateFileHashes(idtype, fname, checkExisting)
	
	def updateAllHashes(self, checkExisting=False, ignoreMissingFiles=True):
		""" Regenerate all hashes for all files in this Manifest. """
		for idtype in MANIFEST2_IDENTIFIERS:
			self.updateTypeHashes(idtype, checkExisting=checkExisting,
				ignoreMissingFiles=ignoreMissingFiles)

	def updateCpvHashes(self, cpv, ignoreMissingFiles=True):
		""" Regenerate all hashes associated to the given cpv (includes all AUX and MISC
		files)."""
		self.updateTypeHashes("AUX", ignoreMissingFiles=ignoreMissingFiles)
		self.updateTypeHashes("MISC", ignoreMissingFiles=ignoreMissingFiles)
		ebuildname = "%s.ebuild" % self._catsplit(cpv)[1]
		self.updateFileHashes("EBUILD", ebuildname, ignoreMissingFiles=ignoreMissingFiles)
		for f in self._getCpvDistfiles(cpv):
			self.updateFileHashes("DIST", f, ignoreMissingFiles=ignoreMissingFiles)

	def updateHashesGuessType(self, fname, *args, **kwargs):
		""" Regenerate hashes for the given file (guesses the type and then
		calls updateFileHashes)."""
		mytype = self.guessType(fname)
		if mytype == "AUX":
			fname = fname[len("files" + os.sep):]
		elif mytype is None:
			return
		myrealtype = self.findFile(fname)
		if myrealtype is not None:
			mytype = myrealtype
		return self.updateFileHashes(mytype, fname, *args, **kwargs)

	def getFileData(self, ftype, fname, key):
		""" Return the value of a specific (type,filename,key) triple, mainly useful
		to get the size for distfiles."""
		return self.fhashdict[ftype][fname][key]

	def getVersions(self):
		""" Returns a list of manifest versions present in the manifest file. """
		rVal = []
		mfname = self.getFullname()
		if not os.path.exists(mfname):
			return rVal
		myfile = io.open(_unicode_encode(mfname,
			encoding=_encodings['fs'], errors='strict'),
			mode='r', encoding=_encodings['repo.content'], errors='replace')
		lines = myfile.readlines()
		myfile.close()
		for l in lines:
			mysplit = l.split()
			if len(mysplit) == 4 and mysplit[0] in MANIFEST1_HASH_FUNCTIONS \
				and 1 not in rVal:
				rVal.append(1)
			elif len(mysplit) > 4 and mysplit[0] in MANIFEST2_IDENTIFIERS \
				and ((len(mysplit) - 3) % 2) == 0 and not 2 in rVal:
				rVal.append(2)
		return rVal

	def _catsplit(self, pkg_key):
		"""Split a category and package, returning a list of [cat, pkg].
		This is compatible with portage.catsplit()"""
		return pkg_key.split("/", 1)