#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Function
# Find duplicate class among java libs.
#
# @Usage
#   $ show-duplicate-java-classes # find jars from current dir
#   $ show-duplicate-java-classes path/to/lib_dir1 /path/to/lib_dir2
#   $ show-duplicate-java-classes -c path/to/class_dir1 -c /path/to/class_dir2
#
# @online-doc https://github.com/oldratlee/useful-scripts/blob/master/docs/java.md#-show-duplicate-java-classes
# @author tg123 (farmer1992 at gmail dot com)
# @author Jerry Lee (oldratlee at gmail dot com)

__author__ = 'tg123'

from glob import glob
from os import walk
from zipfile import ZipFile
from os.path import relpath, isdir
from optparse import OptionParser


def list_jar_file_under_lib_dirs(libs):
    jar_files = set()
    for lib in libs:
        if isdir(lib):
            jar_files |= {f for f in glob(lib + '/*.jar')}
        else:
            jar_files.add(lib)
    return jar_files


def list_class_under_jar_file(jar_file):
    return {f for f in ZipFile(jar_file).namelist() if f.lower().endswith('.class')}


def list_class_under_class_dir(class_dir):
    return {relpath(dir_path + "/" + filename, class_dir)
            for dir_path, _, file_names in walk(class_dir)
            for filename in file_names if filename.lower().endswith('.class')}


def expand_2_class_path(jar_files, class_dirs):
    java_class_2_class_paths = {}
    # list all classes in jar files
    for jar_file in jar_files:
        for class_file in list_class_under_jar_file(jar_file):
            java_class_2_class_paths.setdefault(class_file, set()).add(jar_file)
    # list all classes in class dir
    for class_dir in class_dirs:
        for class_file in list_class_under_class_dir(class_dir):
            java_class_2_class_paths.setdefault(class_file, set()).add(class_dir)

    return java_class_2_class_paths, jar_files | set(class_dirs)


def find_duplicate_classes(java_class_2_class_paths):
    class_path_2_duplicate_classes = {}

    for java_class, class_paths in list(java_class_2_class_paths.items()):
        if len(class_paths) > 1:
            classes = class_path_2_duplicate_classes.setdefault(frozenset(class_paths), set())
            classes.add(java_class)

    return class_path_2_duplicate_classes


def print_class_paths(class_paths):
    print()
    print("=" * 80)
    print("class paths to find:")
    print("=" * 80)
    for idx, class_path in enumerate(class_paths):
        print("%-3d: %s" % (idx + 1, class_path))


if __name__ == '__main__':
    optionParser = OptionParser('usage: %prog '
                                '[-c class-dir1 [-c class-dir2] ...] '
                                '[lib-dir1|jar-file1 [lib-dir2|jar-file2] ...]')
    optionParser.add_option("-c", "--class-dir", dest="class_dirs", default=[], action="append", help="add class dir")
    options, libs = optionParser.parse_args()

    if not options.class_dirs and not libs:
        libs = ['.']

    java_class_2_class_paths, class_paths = expand_2_class_path(
        list_jar_file_under_lib_dirs(libs), options.class_dirs)

    class_path_2_duplicate_classes = find_duplicate_classes(java_class_2_class_paths)

    if not class_path_2_duplicate_classes:
        print("COOL! No duplicate classes found!")
        print_class_paths(class_paths)
        exit()

    print("Found duplicate classes in below class path:")
    for idx, jars in enumerate(class_path_2_duplicate_classes):
        print("%-3d(%d@%d): %s" % (idx + 1, len(class_path_2_duplicate_classes[jars]), len(jars), " ".join(jars)))

    print()
    print("=" * 80)
    print("Duplicate classes detail info:")
    print("=" * 80)
    for idx, (jars, classes) in enumerate(class_path_2_duplicate_classes.items()):
        print("%-3d(%d@%d): %s" % (idx + 1, len(class_path_2_duplicate_classes[jars]), len(jars), " ".join(jars)))
        for i, c in enumerate(classes):
            print("\t%-3d %s" % (i + 1, c))

    print_class_paths(class_paths)
    exit(1)