# Copyright (c) 2013 - present Facebook, Inc.
# All rights reserved.
#
# This source code is licensed under the BSD style license found in the
# LICENSE file in the root directory of this source tree. An additional grant
# of patent rights can be found in the PATENTS file in the same directory.

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals

import argparse
import codecs
import csv
import glob
import json
import logging
import multiprocessing
import os
import shutil
import subprocess
import sys
import time

from . import config, issues, jwlib, utils

# Increase the limit of the CSV parser to sys.maxlimit
csv.field_size_limit(sys.maxsize)

INFER_ANALYZE_BINARY = "InferAnalyze"


def get_infer_version():
    try:
        return subprocess.check_output([
            utils.get_cmd_in_bin_dir(INFER_ANALYZE_BINARY), '-version'])
    except:
        print("Failed to run {0} binary, exiting".
              format(INFER_ANALYZE_BINARY))
        sys.exit(os.EX_UNAVAILABLE)


# https://github.com/python/cpython/blob/aa8ea3a6be22c92e774df90c6a6ee697915ca8ec/Lib/argparse.py
class VersionAction(argparse._VersionAction):
    def __call__(self, parser, namespace, values, option_string=None):
        # set self.version so that argparse version action knows it
        self.version = get_infer_version()
        super(VersionAction, self).__call__(parser,
                                            namespace,
                                            values,
                                            option_string)


class ConfirmIncrementalAction(argparse._StoreTrueAction):
    def __call__(self, parser, namespace, values, option_string=None):
        if not getattr(namespace, 'incremental'):
            parser.error('-ic/--changed-only should only be used with -i')
        super(ConfirmIncrementalAction, self).__call__(parser,
                                                       namespace,
                                                       values,
                                                       option_string)


base_parser = argparse.ArgumentParser(add_help=False)
base_group = base_parser.add_argument_group('global arguments')
base_group.add_argument('-o', '--out', metavar='<directory>',
                        default=config.DEFAULT_INFER_OUT, dest='infer_out',
                        action=utils.AbsolutePathAction,
                        help='Set the Infer results directory')
base_group.add_argument('-i', '--incremental', action='store_true',
                        help='''Analyze only changed procedures and their
                        dependencies''')
base_group.add_argument('-ic', '--changed-only',
                        action=ConfirmIncrementalAction,
                        help='''Same as -i, but does not analyze
                        dependencies of changed procedures.''')
base_group.add_argument('--debug-exceptions', action='store_true',
                        help='''Generate lightweight debugging information:
                        just print the internal exceptions during analysis''')
base_group.add_argument('-g', '--debug', action='store_true',
                        help='Generate all debugging information')
base_group.add_argument('-a', '--analyzer',
                        help='Select the analyzer within: {0}'.format(
                            ', '.join(config.ANALYZERS)),
                        default=config.ANALYZER_INFER)
base_group.add_argument('-nf', '--no-filtering', action='store_true',
                        help='''Also show the results from the experimental
                        checks. Warning: some checks may contain many false
                        alarms''')
base_group.add_argument('--fail-on-bug', action='store_true',
                        help='''Exit with error code %d if Infer found
                        something to report'''
                        % config.BUG_FOUND_ERROR_CODE)

base_group.add_argument('--android-harness', action='store_true',
                        help='''[experimental] Create harness to detect bugs
                        involving the Android lifecycle''')

base_group.add_argument('-l', '--llvm', action='store_true',
                        help='''[experimental] Analyze C or C++ file using the
                        experimental LLVM frontend''')

base_group.add_argument('--log_to_stderr', action='store_true',
                        help='''When set, all logging will go to stderr instead
                        of the log file''')
base_parser.add_argument('-v', '--version',
                         help='''Print the version of Infer and exit''',
                         action=VersionAction)


infer_parser = argparse.ArgumentParser(parents=[base_parser])
infer_group = infer_parser.add_argument_group('backend arguments')
infer_group.add_argument('-j', '--multicore', metavar='n', type=int,
                           default=multiprocessing.cpu_count(),
                           dest='multicore', help='Set the number of cores to '
                           'be used for the analysis (default uses all cores)')
infer_group.add_argument('-x', '--project', metavar='<projectname>',
                           help='Project name, for recording purposes only')

infer_group.add_argument('-r', '--revision', metavar='<githash>',
                           help='The githash, for recording purposes only')

infer_group.add_argument('--buck', action='store_true', dest='buck',
                           help='To use when run with buck')

infer_group.add_argument('--infer_cache', metavar='<directory>',
                           help='Select a directory to contain the infer cache')

infer_group.add_argument('-pr', '--project_root',
                          dest='project_root',
                          default=os.getcwd(),
                          help='Location of the project root '
                          '(default is current directory)')

infer_group.add_argument('--absolute-paths',
                          action='store_true',
                          default=False,
                          help='Report errors with absolute paths')

infer_group.add_argument('--ml_buckets',
                         dest='ml_buckets',
                         help='memory leak buckets to be checked, '
                              'separated by commas. The possible '
                              'buckets are cf (Core Foundation), '
                              'arc, narc (No arc), cpp, unknown_origin')

infer_group.add_argument('-npb', '--no-progress-bar', action='store_true',
                         help='Do not show a progress bar in the analysis')

infer_group.add_argument('--specs-dir',
                          metavar='<dir>',
                          action='append',
                          dest='specs_dirs',
                          help='add dir to the list of directories to be '
                               'searched for spec files. Repeat the argument '
                               'in case multiple folders are needed')
infer_group.add_argument('--specs-dir-list-file',
                         metavar='<file>',
                         help='add the newline-separated directories listed '
                              'in <file> to the list of directories to be '
                              'searched for spec files')

def detect_javac(args):
    for index, arg in enumerate(args):
        if arg == 'javac':
            return index


def get_infer_args(args):
    index = detect_javac(args)
    if index is None:
        cmd_args = args
    else:
        cmd_args = args[:index]
    return infer_parser.parse_args(cmd_args)


def get_javac_args(args):
    javac_args = args[detect_javac(args) + 1:]
    if len(javac_args) == 0:
        return None
    else:
        # replace any -g:.* flag with -g to preserve debugging symbols
        args = map(lambda arg: '-g' if '-g:' in arg else arg, javac_args)
        # skip -Werror
        args = filter(lambda arg: arg != '-Werror', args)
        return args


def remove_infer_out(infer_out):
    # it is safe to ignore errors here because recreating the infer_out
    # directory will fail later
    shutil.rmtree(infer_out, True)


def create_results_dir(results_dir):
    utils.mkdir_if_not_exists(results_dir)
    utils.mkdir_if_not_exists(os.path.join(results_dir, 'specs'))
    utils.mkdir_if_not_exists(os.path.join(results_dir, 'captured'))
    utils.mkdir_if_not_exists(os.path.join(results_dir, 'sources'))


def clean(infer_out):
    directories = ['multicore', 'classnames', 'sources', jwlib.FILELISTS]
    extensions = ['.cfg', '.cg']

    for root, dirs, files in os.walk(infer_out):
        for d in dirs:
            if d in directories:
                path = os.path.join(root, d)
                shutil.rmtree(path)
        for f in files:
            for ext in extensions:
                if f.endswith(ext):
                    path = os.path.join(root, f)
                    os.remove(path)


def help_exit(message):
    print(message)
    infer_parser.print_usage()
    exit(1)


def run_command(cmd, debug_mode, javac_arguments, step, analyzer):
    if debug_mode:
        print('\n{0}\n'.format(' '.join(cmd)))
    try:
        return subprocess.check_call(cmd)
    except subprocess.CalledProcessError as e:
        error_msg = 'Failure during {0}, original command was\n\n{1}\n\n'
        infer_cmd = ['infer', '-g', '-a', analyzer]
        failing_cmd = infer_cmd + ['--', 'javac'] + javac_arguments
        logging.error(error_msg.format(
            step,
            failing_cmd
        ))
        raise e


class Infer:

    def __init__(self, args, javac_args):
        self.args = args
        if self.args.analyzer not in config.ANALYZERS:
            help_exit('Unknown analysis mode \"{0}\"'
                      .format(self.args.analyzer))

        utils.configure_logging(self.args.debug)

        self.javac = jwlib.CompilerCall(javac_args)

        if not self.javac.args.version:
            if javac_args is None:
                help_exit('No javac command detected')

            if self.args.infer_out is None:
                help_exit('Expect Infer results directory')

            if self.args.buck:
                self.args.infer_out = os.path.join(
                    self.javac.args.classes_out,
                    config.BUCK_INFER_OUT)
                self.args.infer_out = os.path.abspath(self.args.infer_out)

            try:
                os.mkdir(self.args.infer_out)
            except OSError as e:
                if not os.path.isdir(self.args.infer_out):
                    raise e

            self.stats = {'int': {}}
            self.timing = {}

        if self.args.specs_dirs:
            # Each dir passed in input is prepended by '-lib'.
            # Convert each path to absolute because when running from
            # cluster Makefiles (multicore mode) InferAnalyze creates the wrong
            # absolute path from within the multicore folder
            self.args.specs_dirs = [item
                                    for argument in
                                    (['-lib', os.path.abspath(path)] for path in
                                     self.args.specs_dirs)
                                    for item in argument]
        if self.args.specs_dir_list_file:
            # Convert the path to the file list to an absolute path, because
            # the analyzer will run from different paths and may not find the
            # file otherwise.
            self.args.specs_dir_list_file = \
                ['-specs-dir-list-file',
                 os.path.abspath(self.args.specs_dir_list_file)]


    def clean_exit(self):
        if os.path.isdir(self.args.infer_out):
            print('removing', self.args.infer_out)
            shutil.rmtree(self.args.infer_out)
        exit(os.EX_OK)

    def run_infer_frontend(self):

        infer_cmd = [utils.get_cmd_in_bin_dir('InferJava')]

        if not self.args.absolute_paths:
            infer_cmd += ['-project_root', self.args.project_root]

        infer_cmd += [
            '-results_dir', self.args.infer_out,
            '-verbose_out', self.javac.verbose_out,
        ]

        if os.path.isfile(config.MODELS_JAR):
            infer_cmd += ['-models', config.MODELS_JAR]

        infer_cmd.append('-no-static_final')

        if self.args.debug:
            infer_cmd.append('-debug')
        if self.args.analyzer == config.ANALYZER_TRACING:
            infer_cmd.append('-tracing')
        if self.args.android_harness:
            infer_cmd.append('-harness')

        return run_command(
            infer_cmd,
            self.args.debug,
            self.javac.original_arguments,
            'frontend',
            self.args.analyzer
        )

    def compile(self):
        return self.javac.run()

    def analyze(self):
        logging.info('Starting analysis')
        infer_analyze = [
            utils.get_cmd_in_bin_dir(INFER_ANALYZE_BINARY),
            '-results_dir',
            self.args.infer_out
        ]
        infer_options = []

        # remove specs if possible so that old issues are less likely
        # to be reported
        infer_options += ['-allow_specs_cleanup']

        if self.args.analyzer == config.ANALYZER_ERADICATE:
            infer_options += ['-checkers', '-eradicate']
        elif self.args.analyzer == config.ANALYZER_CHECKERS:
            infer_options += ['-checkers']
        else:
            if self.args.analyzer == config.ANALYZER_TRACING:
                infer_options.append('-tracing')
            if os.path.isfile(config.MODELS_JAR):
                infer_options += ['-models', config.MODELS_JAR]

        if self.args.infer_cache:
            infer_options += ['-infer_cache', self.args.infer_cache]

        if self.args.ml_buckets:
            infer_options += ['-ml_buckets', self.args.ml_buckets]

        if self.args.no_progress_bar:
            infer_options += ['-no_progress_bar']

        if self.args.debug:
            infer_options += [
                '-developer_mode',
                '-html',
                '-dotty',
                '-print_types',
                '-trace_error',
                '-print_buckets',
                '-notest'
            ]
            self.args.no_filtering = True

        elif self.args.debug_exceptions:
            infer_options.append('-developer_mode')
            self.args.no_filtering = True

        if self.args.incremental:
            if self.args.changed_only:
                infer_options.append('-incremental_changed_only')
            else:
                infer_options.append('-incremental')

        if self.args.specs_dirs:
            infer_options += self.args.specs_dirs

        if self.args.specs_dir_list_file:
            infer_options += self.args.specs_dir_list_file

        exit_status = os.EX_OK

        if self.args.buck:
            infer_options += ['-project_root', os.getcwd(), '-java']
            if self.javac.args.classpath is not None:
                for path in self.javac.args.classpath.split(os.pathsep):
                    if os.path.isfile(path):
                        infer_options += ['-ziplib', os.path.abspath(path)]
        elif self.args.project_root:
            infer_options += ['-project_root', self.args.project_root]

        if self.args.multicore == 1:
            analysis_start_time = time.time()
            analyze_cmd = infer_analyze + infer_options
            exit_status = run_command(
                analyze_cmd,
                self.args.debug,
                self.javac.original_arguments,
                'analysis',
                self.args.analyzer
            )
            elapsed = utils.elapsed_time(analysis_start_time)
            self.timing['analysis'] = elapsed
            self.timing['makefile_generation'] = 0

        else:
            if self.args.analyzer == config.ANALYZER_ERADICATE:
                infer_analyze.append('-intraprocedural')
            if self.args.analyzer == config.ANALYZER_CHECKERS:
                os.environ['INFER_ONDEMAND'] = 'Y'

            os.environ['INFER_OPTIONS'] = ' '.join(infer_options)

            multicore_dir = os.path.join(self.args.infer_out, 'multicore')
            pwd = os.getcwd()
            if os.path.isdir(multicore_dir):
                shutil.rmtree(multicore_dir)
            os.mkdir(multicore_dir)
            os.chdir(multicore_dir)
            analyze_cmd = infer_analyze + ['-makefile', 'Makefile']
            analyze_cmd += infer_options
            makefile_generation_start_time = time.time()
            makefile_status = run_command(
                analyze_cmd,
                self.args.debug,
                self.javac.original_arguments,
                'create_makefile',
                self.args.analyzer
            )
            elapsed = utils.elapsed_time(makefile_generation_start_time)
            self.timing['makefile_generation'] = elapsed
            exit_status += makefile_status
            if makefile_status == os.EX_OK:
                make_cmd = ['make', '-k', '-j', str(self.args.multicore)]
                if not self.args.debug:
                    make_cmd += ['-s']
                analysis_start_time = time.time()
                make_status = run_command(
                    make_cmd,
                    self.args.debug,
                    self.javac.original_arguments,
                    'run_makefile',
                    self.args.analyzer
                )
                elapsed = utils.elapsed_time(analysis_start_time)
                self.timing['analysis'] = elapsed
                os.chdir(pwd)
                exit_status += make_status

        if self.args.buck and exit_status == os.EX_OK:
            clean(self.args.infer_out)

        return exit_status

    def update_stats_with_warnings(self, csv_report):
        with open(csv_report, 'r') as file_in:
            reader = utils.locale_csv_reader(file_in)
            rows = [row for row in reader][1:]
            for row in rows:
                key = row[issues.CSV_INDEX_TYPE]
                previous_value = self.stats['int'].get(key, 0)
                self.stats['int'][key] = previous_value + 1

    def create_report(self):
        """Report statistics about the computation and create a CSV file
        containing the list or errors found during the analysis"""

        out_dir = self.args.infer_out
        csv_report = os.path.join(out_dir, config.CSV_REPORT_FILENAME)
        json_report = os.path.join(out_dir, config.JSON_REPORT_FILENAME)
        procs_report = os.path.join(self.args.infer_out, 'procs.csv')

        infer_print_cmd = [utils.get_cmd_in_bin_dir('InferPrint')]
        infer_print_options = [
            '-q',
            '-results_dir', self.args.infer_out,
            '-bugs', csv_report,
            '-bugs_json', json_report,
            '-procs', procs_report,
            '-analyzer', self.args.analyzer
        ]
        if self.javac.annotations_out is not None:
            infer_print_options += [
                '-local_config', self.javac.annotations_out]
        exit_status = subprocess.check_call(
            infer_print_cmd + infer_print_options
        )
        if exit_status != os.EX_OK:
            logging.error('Error with InferPrint with the command: '
                          + infer_print_cmd)
        else:
            issues.clean_csv(self.args, csv_report)
            issues.clean_json(self.args, json_report)
            self.update_stats_with_warnings(csv_report)

        return exit_status

    def read_proc_stats(self):
        proc_stats_path = os.path.join(
            self.args.infer_out,
            config.PROC_STATS_FILENAME)

        # capture and compile mode do not create proc_stats.json
        if os.path.isfile(proc_stats_path):
            proc_stats = utils.load_json_from_path(proc_stats_path)
            self.stats['int'].update(proc_stats)

    def save_stats(self):
        """Print timing information to infer_out/stats.json"""
        self.stats['float'] = {
            'capture_time': self.timing.get('capture', 0.0),
            'makefile_generation_time': self.timing.get(
                'makefile_generation', 0.0),
            'analysis_time': self.timing.get('analysis', 0.0),
            'reporting_time': self.timing.get('reporting', 0.0),
        }
        self.stats['normal'] = {
            'analyzer': self.args.analyzer,
            'infer_version': utils.infer_version()
        }

        stats_path = os.path.join(self.args.infer_out, config.STATS_FILENAME)
        utils.dump_json_to_path(self.stats, stats_path)


    def close(self):
        os.remove(self.javac.verbose_out)
        os.remove(self.javac.annotations_out)

    def analyze_and_report(self):
        should_print_errors = False
        if self.args.analyzer not in [config.ANALYZER_COMPILE,
                                      config.ANALYZER_CAPTURE]:
            if self.analyze() == os.EX_OK:
                reporting_start_time = time.time()
                report_status = self.create_report()
                elapsed = utils.elapsed_time(reporting_start_time)
                self.timing['reporting'] = elapsed
                self.read_proc_stats()
                self.print_analysis_stats()
                if report_status == os.EX_OK and not self.args.buck:
                    json_report = os.path.join(self.args.infer_out,
                                               config.JSON_REPORT_FILENAME)
                    bugs_out = os.path.join(self.args.infer_out,
                                            config.BUGS_FILENAME)
                    issues.print_and_save_errors(json_report, bugs_out)

    def print_analysis_stats(self):
        procs_total = self.stats['int']['procedures']
        files_total = self.stats['int']['files']
        procs_str = utils.get_plural('procedure', procs_total)
        files_str = utils.get_plural('file', files_total)
        print('Analyzed %s in %s' % (procs_str, files_str))

    def start(self):
        if self.javac.args.version:
            if self.args.buck:
                key = self.args.analyzer
                print(utils.infer_key(key), file=sys.stderr)
            else:
                return self.javac.run()
        else:
            start_time = time.time()

            self.compile()
            if self.args.analyzer == config.ANALYZER_COMPILE:
                return os.EX_OK

            self.run_infer_frontend()
            self.timing['capture'] = utils.elapsed_time(start_time)
            if self.args.analyzer == config.ANALYZER_CAPTURE:
                return os.EX_OK

            self.analyze_and_report()
            self.close()
            self.timing['total'] = utils.elapsed_time(start_time)
            self.save_stats()

            return self.stats