# Utilities for layerindex-web
#
# Copyright (C) 2013 Intel Corporation
# Author: Paul Eggleton <paul.eggleton@linux.intel.com>
#
# Licensed under the MIT license, see COPYING.MIT for details
#
# SPDX-License-Identifier: MIT

import sys
import os
import tempfile
import subprocess
import logging
import time
import fcntl
import signal
import errno
import shutil
import codecs
import re
from datetime import datetime
from bs4 import BeautifulSoup

def get_branch(branchname):
    from layerindex.models import Branch
    res = list(Branch.objects.filter(name=branchname)[:1])
    if res:
        return res[0]
    return None

def get_layer(layername):
    from layerindex.models import LayerItem
    res = list(LayerItem.objects.filter(name=layername)[:1])
    if res:
        return res[0]
    return None

def get_layer_var(config_data, var, logger):
    collection = config_data.getVar('BBFILE_COLLECTIONS', True)
    if collection:
        collection = collection.strip()
        collection_list = collection.split()
        collection = collection_list[0]
        layerdir = config_data.getVar('LAYERDIR', True)
        if len(collection_list) > 1:
            if collection_list[0] == 'core':
                # Many layers append BBFILE_COLLECTIONS and therefore have 'core <layer>'
                collection = collection_list[1]
                logger.debug('%s: multiple collections found, ignoring the first one (\'core\') and handling (%s) only' % (layerdir, collection))
            else:
                logger.warn('%s: multiple collections found, handling first one (%s) only' % (layerdir, collection))
        if var == 'BBFILE_COLLECTIONS':
            return collection
    value = config_data.getVar('%s_%s' % (var, collection), True)
    if not value:
        value = config_data.getVar(var, True)
    return value or ''

def is_deps_satisfied(req_col, req_ver, collections):
    """ Check whether required collection and version are in collections"""
    for existed_col, existed_ver in collections:
        if req_col == existed_col:
            # If there is no version constraint, return True when collection matches
            if not req_ver:
                return True
            else:
                # If there is no version in the found layer, then don't use this layer.
                if not existed_ver:
                    continue
                (op, dep_version) = req_ver.split()
                success = bb.utils.vercmp_string_op(existed_ver, dep_version, op)
                if success:
                    return True
    # Return False when not found
    return False

def get_dependency_layer(depname, branch=None, version_str=None, logger=None):
    from layerindex.models import LayerItem, LayerBranch

    if branch:
        # Get LayerBranch with a layer that has a name that matches depname, or
        # a LayerBranch that has the collection name depname
        # AND also match branch [YOCTO #15221]
        res = list(LayerBranch.objects.filter(layer__name=depname,branch__name=branch)) + \
              list(LayerBranch.objects.filter(collection=depname,branch__name=branch))
    else:
        # Get any LayerBranch with a layer that has a name that matches depname, or
        # a LayerBranch that has the collection name depname.
        res = list(LayerBranch.objects.filter(layer__name=depname)) + \
              list(LayerBranch.objects.filter(collection=depname))

    # Nothing found, return.
    if not res:
        return None

    # If there is no version constraint, return the first one found.
    if not version_str:
        return res[0].layer

    (operator, dep_version) = version_str.split()
    for layerbranch in res:
        layer_ver = layerbranch.version

        # If there is no version in the found layer, then don't use this layer.
        if not layer_ver:
            continue

        try:
            success = bb.utils.vercmp_string_op(layer_ver, version_str, operator)
        except bb.utils.VersionStringException as vse:
            raise vse

        if success:
            return layerbranch.layer

    return None

def add_dependencies(layerbranch, config_data, logger=None):
    _add_dependency("LAYERDEPENDS", 'dependency', layerbranch, config_data, logger=logger)

def add_recommends(layerbranch, config_data, logger=None):
    _add_dependency("LAYERRECOMMENDS", 'recommends', layerbranch, config_data, logger=logger, required=False)

def _add_dependency(var, name, layerbranch, config_data, logger=None, required=True):
    from layerindex.models import LayerBranch, LayerDependency

    layer_name = layerbranch.layer.name
    branch_name = layerbranch.branch.name
    var_name = layer_name

    if layerbranch.collection:
        var_name = layerbranch.collection


    dep_list = config_data.getVar("%s_%s" % (var, var_name), True)

    if not dep_list:
        return

    try:
        dep_dict = bb.utils.explode_dep_versions2(dep_list)
    except bb.utils.VersionStringException as vse:
        logger.debug('Error parsing %s_%s for %s\n%s' % (var, var_name, layer_name, str(vse)))
        return

    need_remove = LayerDependency.objects.filter(layerbranch=layerbranch).filter(required=required)
    for dep, ver_list in list(dep_dict.items()):
        ver_str = None
        if ver_list:
            ver_str = ver_list[0]

        try:
            dep_layer = get_dependency_layer(dep, branch_name, ver_str, logger)
        except bb.utils.VersionStringException as vse:
            if logger:
                logger.error('Error getting %s %s for %s:%s\n%s' %(name, dep. layer_name, branch_name, str(vse)))
            continue

        # No layer found.
        if not dep_layer:
            if logger:
                if required:
                    logger.error('Cannot resolve %s %s (version %s) for %s' % (name, dep, ver_str, layer_name))
                else:
                    logger.warning('Cannot resolve %s %s (version %s) for %s' % (name, dep, ver_str, layer_name))
            continue

        # Preparing to remove obsolete ones
        if need_remove:
            need_remove = need_remove.exclude(dependency=dep_layer)

        # Skip existing entries.
        existing = list(LayerDependency.objects.filter(layerbranch=layerbranch).filter(required=required).filter(dependency=dep_layer))
        if existing:
            logger.debug('Skipping %s - already a dependency for %s' % (dep, layer_name))
            continue

        if logger:
            logger.debug('Adding %s %s to %s' % (name, dep_layer.name, layer_name))

        layerdep = LayerDependency()
        layerdep.layerbranch = layerbranch
        layerdep.dependency = dep_layer
        layerdep.required = required
        layerdep.save()

    if need_remove:
        import settings
        remove_layer_dependencies = getattr(settings, 'REMOVE_LAYER_DEPENDENCIES', False)
        if remove_layer_dependencies:
            logger.info('Removing obsolete dependencies "%s" for layer %s' % (need_remove, layer_name))
            need_remove.delete()
        else:
            logger.warn('Dependencies "%s" are not in %s\'s conf/layer.conf' % (need_remove, layer_name))
            logger.warn('Either set REMOVE_LAYER_DEPENDENCIES to remove them from the database, or fix conf/layer.conf')

def set_layerbranch_collection_version(layerbranch, config_data, logger=None):
    layerbranch.collection = get_layer_var(config_data, 'BBFILE_COLLECTIONS', logger)
    ver_str = "LAYERVERSION_"
    if layerbranch.collection:
        layerbranch.collection = layerbranch.collection.strip()
        ver_str += layerbranch.collection
        layerbranch.version = config_data.getVar(ver_str, True)

def setup_tinfoil(bitbakepath, enable_tracking, loglevel=None):
    sys.path.insert(0, bitbakepath + '/lib')
    import bb.tinfoil
    import bb.cooker
    import bb.data
    try:
        tinfoil = bb.tinfoil.Tinfoil(tracking=enable_tracking)
    except TypeError:
        # old API
        tinfoil = bb.tinfoil.Tinfoil()
        if enable_tracking:
            tinfoil.cooker.enableDataTracking()
    tinfoil.logger.setLevel(logging.WARNING)
    if loglevel:
        tinfoil.logger.setLevel(loglevel)
    try:
        tinfoil.prepare(config_only = True)
    except bb.BBHandledException:
        sys.exit(1)
    finally:
        # Handle any remaining events - needed if server failed and logged errors
        # FIXME tinfoil.prepare() should really be doing this for us!
        while True:
            event = tinfoil.wait_event()
            if not event:
                break
            if isinstance(event, logging.LogRecord):
                if event.taskpid == 0 or event.levelno > logging.INFO:
                    tinfoil.logger.handle(event)

    return tinfoil

def explode_dep_versions2(bitbakepath, deps):
    bblib = bitbakepath + '/lib'
    if not bblib in sys.path:
        sys.path.insert(0, bblib)
    import bb.utils
    return bb.utils.explode_dep_versions2(deps)

def is_commit_ancestor(repodir, commit, logger):
    """
    Check if the given SHA1 hash is an ancestor in the currently checked out branch.
    NOTE: This will not match commits which have been cherry-picked.
    """
    try:
        # check if commit is a sha1 hash
        if re.match('[0-9a-f]{40}', commit):
            # check if the commit is an ancestor
            cmd = "GIT_DIR=%s/.git git merge-base --is-ancestor %s HEAD" % (repodir, commit)
            logger.debug('Running "%s"' % cmd)
            ret, output = subprocess.getstatusoutput(cmd)
            if ret == 0:
                return True
            elif ret == 1:
                logger.debug('output: %s' % output)
                return False
            else:
                raise Exception('Failed to run command: %s: ret: %s, output: %s' % (cmd, ret, output))
        else:
            raise Exception('is_commit_ancestor: "commit" must be a SHA1 hash')
    except Exception as esc:
        logger.warn(esc)

def checkout_repo(repodir, commit, logger, force=False):
    """
    Check out a revision in a repository, ensuring that untracked/uncommitted
    files don't get in the way.
    WARNING: this will throw away any untracked/uncommitted files in the repo,
    so it is only suitable for use with repos where you don't care about such
    things (which we don't for the layer repos that we use)
    """
    if force:
        currentref = ''
    else:
        try:
            # The "git rev-parse HEAD" returns "fatal: ambiguous argument 'HEAD'"
            # when a repo is unable to check out after git clone:
            # git clone <url>
            # warning: remote HEAD refers to nonexistent ref, unable to checkout.
            # So check and avoid that
            currentref = runcmd(['git', 'rev-parse', 'HEAD'], repodir, logger=logger).strip()
        except Exception as esc:
            logger.warn(esc)
            currentref = ''
    if currentref != commit:
        # Reset in case there are added but uncommitted changes
        runcmd(['git', 'reset', '--hard'], repodir, logger=logger)
        # Drop any untracked files in case these cause problems (either because
        # they will exist in the revision we're checking out, or will otherwise
        # interfere with operation, e.g. stale pyc files)
        runcmd(['git', 'clean', '-qdfx'], repodir, logger=logger)
        # Now check out the revision
        runcmd(['git', 'checkout', commit], repodir, logger=logger)

def checkout_layer_branch(layerbranch, repodir, actual_branch=None, logger=None):
    if actual_branch:
        branchname = actual_branch
    else:
        branchname = layerbranch.get_checkout_branch()
    checkout_repo(repodir, 'origin/%s' % branchname, logger)

def is_layer_valid(layerdir):
    conf_file = os.path.join(layerdir, "conf", "layer.conf")
    if not os.path.isfile(conf_file):
        return False
    return True

def is_branch_valid(layerdir, branch):
    import git

    g = git.cmd.Git(layerdir)
    if g.rev_parse('--is-bare-repository') != 'false':
        raise Exception('is_branch_valid: git repository is a bare repository')
    try:
        g.rev_parse('--verify', 'origin/%s' % branch)
    except git.exc.GitCommandError:
        return False
    return True

def parse_conf(conf_file, d):
    if hasattr(bb.parse, "handle"):
        # Newer BitBake
        if hasattr(bb.parse.parse_py.ConfHandler, "__addpylib_regexp__"):
            data = bb.parse.handle(conf_file, d, include=True, baseconfig=True)
        else:
            data = bb.parse.handle(conf_file, d, include=True)
    else:
        # Older BitBake (1.18 and below)
        data = bb.cooker._parse(conf_file, d)
    return data

def parse_layer_conf(layerdir, data, logger=None):
    conf_file = os.path.join(layerdir, "conf", "layer.conf")

    if not is_layer_valid(layerdir):
        if logger:
            logger.error("Cannot find layer.conf: %s"% conf_file)
        return

    data.setVar('LAYERDIR', str(layerdir))
    data = parse_conf(conf_file, data)
    data.expandVarref('LAYERDIR')

child_pid = 0
def runcmd(cmd, destdir=None, printerr=True, outfile=None, logger=None, shell=False):
    """
        execute command, raise CalledProcessError if fail
        return output if succeed
    """
    if logger:
        logger.debug("run cmd '%s' in %s" % (cmd, os.getcwd() if destdir is None else destdir))
    if outfile:
        out = open(outfile, 'wb+')
    else:
        out = tempfile.TemporaryFile()

    def onsigusr2(sig, frame):
        # Kill the child process
        os.kill(child_pid, signal.SIGTERM)
    signal.signal(signal.SIGUSR2, onsigusr2)
    try:
        proc = subprocess.Popen(cmd, stdout=out, stderr=out, cwd=destdir, shell=shell)
        global child_pid
        child_pid = proc.pid
        proc.poll()
        while proc.returncode is None:
            proc.poll()
            time.sleep(0.05)
        if proc.returncode:
            out.seek(0)
            output = out.read()
            output = output.decode('utf-8', errors='replace').strip()
            if printerr:
                if logger:
                    logger.error("%s" % output)
                else:
                    sys.stderr.write("%s\n" % output)
            e = subprocess.CalledProcessError(proc.returncode, cmd)
            e.output = output
            raise e

        out.seek(0)
        output = out.read()
        output = output.decode('utf-8', errors='replace').strip()
        if logger:
            logger.debug("output: %s" % output.rstrip() )
    finally:
        signal.signal(signal.SIGUSR2, signal.SIG_DFL)
        if outfile:
            out.close()
    return output

def setup_django():
    import django
    # Get access to our Django model
    newpath = os.path.abspath(os.path.dirname(__file__) + '/..')
    sys.path.append(newpath)
    os.environ['DJANGO_SETTINGS_MODULE'] = 'settings'
    django.setup()

def logger_create(name):
    logger = logging.getLogger(name)
    loggerhandler = logging.StreamHandler()
    loggerhandler.setFormatter(logging.Formatter("%(levelname)s: %(message)s"))
    logger.addHandler(loggerhandler)
    logger.setLevel(logging.INFO)
    return logger

class ListHandler(logging.Handler):
    """Logging handler which accumulates formatted log records in a list, returning the list on demand"""
    def __init__(self):
        self.log = []
        logging.Handler.__init__(self, logging.WARNING)
    def emit(self, record):
        self.log.append('%s\n' % self.format(record))
    def read(self):
        log = self.log
        self.log = []
        return log


def lock_file(fn, timeout=30, logger=None):
    start = time.time()
    last = start
    counter = 1
    while True:
        lock = open(fn, 'w')
        try:
            fcntl.flock(lock, fcntl.LOCK_EX | fcntl.LOCK_NB)
            return lock
        except IOError:
            lock.close()
            current = time.time()
            if current - start > timeout:
                return None
            # Print a message in every 5 seconds
            if logger and (current - last > 5):
                last = current
                logger.info('Trying to get lock on %s (tried %s seconds) ...' % (fn, (5 * counter)))
                counter += 1

def unlock_file(lock):
    fcntl.flock(lock, fcntl.LOCK_UN)


def rmtree_force(pth):
    """
    Delete a directory tree ignoring any ENOENT errors.
    Mainly used to avoid errors when we're racing against bitbake deleting bitbake.lock/bitbake.sock
    (and anything else it happens to create in our temporary build directory in future)
    """
    def rmtree_force_onerror(fn, fullname, exc_info):
        if isinstance(exc_info[1], OSError) and exc_info[1].errno == errno.ENOENT:
            pass
        else:
            raise

    shutil.rmtree(pth, onerror=rmtree_force_onerror)


def chain_unique(*iterables):
    """Chain unique objects in a list of querysets, preserving order"""
    seen = set()
    for element in iterables:
        for item in element:
            k = item.id
            if k not in seen:
                seen.add(k)
                yield item

def setup_core_layer_sys_path(settings, branchname):
    """
    Add OE-Core's lib/oe directory to sys.path in order to allow importing
    OE python modules
    """
    core_layer = get_layer(settings.CORE_LAYER_NAME)
    core_layerbranch = core_layer.get_layerbranch(branchname)
    if core_layerbranch:
        core_urldir = core_layer.get_fetch_dir()
        core_repodir = os.path.join(settings.LAYER_FETCH_DIR, core_urldir)
        core_layerdir = os.path.join(core_repodir, core_layerbranch.vcs_subdir)
        sys.path.insert(0, os.path.join(core_layerdir, 'lib'))


def run_command_interruptible(cmd):
    """
    Run a command with output displayed on the console, but ensure any Ctrl+C is
    processed only by the child process.
    """
    def reenable_sigint():
        signal.signal(signal.SIGINT, signal.SIG_DFL)

    signal.signal(signal.SIGINT, signal.SIG_IGN)
    try:
        process = subprocess.Popen(
            cmd, cwd=os.path.dirname(sys.argv[0]), shell=True, preexec_fn=reenable_sigint, stdout=subprocess.PIPE, stderr=subprocess.STDOUT
        )

        reader = codecs.getreader('utf-8')(process.stdout, errors='surrogateescape')
        buf = ''
        while True:
            out = reader.read(1, 1)
            if out:
                sys.stdout.write(out)
                sys.stdout.flush()
                buf += out
            elif out == '' and process.poll() != None:
                break

    finally:
        signal.signal(signal.SIGINT, signal.SIG_DFL)
    return process.returncode, buf


def sanitise_html(html):
    soup = BeautifulSoup(html, "html.parser")
    for tag in soup.findAll(True):
        if tag.name not in ['strong', 'em', 'b', 'i', 'p', 'ul', 'ol', 'li', 'br', 'p']:
            tag.hidden = True
        elif tag.attrs:
            tag.attrs = []

    return soup.renderContents()

def squashspaces(string):
    return re.sub("\s+", " ", string).strip()

def sha256_file(ifn):
    import hashlib
    shash = hashlib.sha256()
    with open(ifn, 'rb') as f:
        for line in f:
            shash.update(line)
    return shash.hexdigest()

def timesince2(date, date2=None):
    # Based on http://www.didfinishlaunchingwithoptions.com/a-better-timesince-template-filter-for-django/
    if date2 is None:
        date2 = datetime.now()
    if date > date2:
        return '0 seconds'
    diff = date2 - date
    periods = (
        (diff.days // 365, 'year', 'years'),
        (diff.days // 30, 'month', 'months'),
        (diff.days // 7, 'week', 'weeks'),
        (diff.days, 'day', 'days'),
        (diff.seconds // 3600, 'hour', 'hours'),
        (diff.seconds // 60, 'minute', 'minutes'),
        (diff.seconds, 'second', 'seconds'),
    )
    for period, singular, plural in periods:
        if period:
            return '%d %s' % (period, singular if period == 1 else plural)
    return '0 seconds'

class ProgressWriter():
    def __init__(self, logdir, task_id, logger=None):
        self.logger = logger
        self.fn = os.path.join(logdir, '%s.progress' % task_id)
        self.last_value = None
        self.write('')

    def write(self, value):
        if self.fn is None:
            return
        if value == self.last_value:
            return
        try:
            with open(self.fn + '.temp', 'w') as f:
                f.write(str(value))
            os.rename(self.fn + '.temp', self.fn)
        except Exception as e:
            if self.logger is not None:
                self.logger.warning('Failed to write to progress file %s: %s' % (self.fn, str(e)))

class ProgressReader():
    def __init__(self, logdir, task_id, logger=None):
        self.fn = os.path.join(logdir, '%s.progress' % task_id)
        self.fd = None
        self.logger = logger
        self.last_mtime = None
        self.last_value = None

    def read(self):
        result = None
        try:
            mtime = os.path.getmtime(self.fn)
            if mtime != self.last_mtime:
                with open(self.fn, 'r') as f:
                    result = f.read()
        except Exception as e:
            if self.logger is not None:
                self.logger.warning('Failed to read progress: %s' % str(e))
        return result

def string_to_query(querystr, fieldnames):
    # Inspired by http://julienphalip.com/post/2825034077/adding-search-to-a-django-site-in-a-snap
    # (reimplemented a bit more simply)
    from django.db.models import Q
    keywords = [item for item in re.split(r"\s|\"(.*)?\"|'.*?'", querystr) if item]
    query = None
    for keyword in keywords:
        fquery = None
        for fieldname in fieldnames:
            q = Q(**{'%s__icontains' % fieldname: keyword})
            if fquery is None:
                fquery = q
            else:
                fquery = fquery | q
        if query is None:
            query = fquery
        else:
            query = query & fquery
    return query