#!/usr/bin/env python3
"""
Script add PIT mutation plugin to maven files and run mutations.
"""
import argparse
import os
import os.path
import shutil
import subprocess
import sys
import xml.etree.ElementTree as ET

PIT_GROUP_ID = 'org.pitest'
PIT_ARTIFACT_ID = 'pitest-maven'
PIT_VERSION = '1.14.4'
PIT_JUNIT5_ARTIFACT_ID = 'pitest-junit5-plugin'
PIT_JUNIT5_VERSION = '1.2.0'
NAMESPACES = {'': 'http://maven.apache.org/POM/4.0.0'}
for prefix, url in NAMESPACES.items():
    ET.register_namespace(prefix, url)

MUTATORS = [
    'STRONGER'
]
OPEN_COMMAND = 'x-www-browser' # or xdg-open


def create_args():
    parser = argparse.ArgumentParser()
    parser.add_argument('-pl', '--projects')
    parser.add_argument('-pn', '--project-name')
    parser.add_argument('-am', '--also-make', action='store_true')
    parser.add_argument('-q', '--quiet', action='store_true')
    parser.add_argument('globs', nargs='+')
    return parser


def get_pom_files():
    for root, dirs, files in os.walk('.'):
        for file in files:
            if file == 'pom.xml':
                yield os.path.join(root, file)


def make_file_backup(file):
    dst = '%s.bak.%d' % (file, os.getpid())
    shutil.copyfile(file, dst)
    return file, dst


def update_pom(file, project, globs):
    tree = ET.parse(file)
    root = tree.getroot()

    artifact_id = root.find('./artifactId', NAMESPACES).text

    build = root.find('./build', NAMESPACES)
    if build is None:
        build = ET.SubElement(root, 'build')
    plugins = build.find('./plugins', NAMESPACES)
    if plugins is None:
        plugins = ET.SubElement(build, 'plugins')

    plugin = ET.SubElement(plugins, 'plugin')
    ET.SubElement(plugin, 'groupId').text = PIT_GROUP_ID
    ET.SubElement(plugin, 'artifactId').text = PIT_ARTIFACT_ID
    ET.SubElement(plugin, 'version').text = PIT_VERSION

    dependencies = ET.SubElement(plugin, 'dependencies')
    dependency = ET.SubElement(dependencies, 'dependency')
    ET.SubElement(dependency, 'groupId').text = PIT_GROUP_ID
    ET.SubElement(dependency, 'artifactId').text = PIT_JUNIT5_ARTIFACT_ID
    ET.SubElement(dependency, 'version').text = PIT_JUNIT5_VERSION

    configuration = ET.SubElement(plugin, 'configuration')

    if artifact_id == project or project is None:
        ET.SubElement(configuration, 'skip').text = 'False'
        target_classes = ET.SubElement(configuration, 'targetClasses')
        target_tests = ET.SubElement(configuration, 'targetTests')
        for glob in globs:
            ET.SubElement(target_classes, 'param').text = glob
            ET.SubElement(target_tests, 'param').text = glob
        mutators = ET.SubElement(configuration, 'mutators')
        for mutator in MUTATORS:
            ET.SubElement(mutators, 'mutator').text = mutator
        formats = ET.SubElement(configuration, 'outputFormats')
        ET.SubElement(formats, 'outputFormat').text = 'HTML'
        ET.SubElement(formats, 'outputFormat').text = 'XML'
    else:
        ET.SubElement(configuration, 'skip').text = 'True'

    tree.write(file)


def run_mutation_coverage(args):
    command = ['mvn', '--batch-mode', 'test-compile', 'org.pitest:pitest-maven:mutationCoverage']
    if args.also_make:
        command.append('--also-make')
    if args.projects:
        command.append('--projects')
        command.append(args.projects)
    if args.quiet:
        command.append('--quiet')
    subprocess.call(' '.join(command), shell=True, stdout=sys.stdout, stderr=sys.stderr)


def print_details(filename):
    subprocess.call(['pandoc', '--to', 'plain', filename], stdout=sys.stdout, stderr=sys.stderr)


def open_result(project):
    target = os.path.join(project, 'target', 'pit-reports')
    dirs = os.listdir(target)
    if dirs:
        last_dir = sorted(dirs)[-1]
        index_file = os.path.join(target, last_dir, 'index.html')
        if os.path.isfile(index_file):
            print_details(index_file)
            print('Report:', os.path.abspath(index_file))
            subprocess.call([OPEN_COMMAND, os.path.abspath(index_file)])


def update_pom_files(args):
    backup_files = []
    try:
        for file in get_pom_files():
            backup_files.append(make_file_backup(file))
            update_pom(file, args.project_name or args.projects, args.globs)

        run_mutation_coverage(args)
        open_result(args.projects)
    finally:
        for orig, backup in backup_files:
            shutil.move(backup, orig)


def main():
    args = create_args().parse_args()
    update_pom_files(args)


if __name__ == '__main__':
    main()