#!/usr/bin/env python3
#
# This file is part of the MicroPython project, http://micropython.org/
#
# The MIT License (MIT)
#
# Copyright (c) 2020 Damien P. George
# Copyright (c) 2020 Jim Mussared
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

import argparse
import glob
import itertools
import os
import re
import subprocess

# Relative to top-level repo dir.
PATHS = [
 # C
 "extmod/*.[ch]",
 "extmod/btstack/*.[ch]",
 "extmod/nimble/*.[ch]",
 "lib/mbedtls_errors/tester.c",
 "lib/netutils/*.[ch]",
 "lib/timeutils/*.[ch]",
 "lib/utils/*.[ch]",
 "mpy-cross/*.[ch]",
 "ports/*/*.[ch]",
 "ports/windows/msvc/**/*.[ch]",
 "py/*.[ch]",
 # Python
 "drivers/**/*.py",
 "examples/**/*.py",
 "extmod/**/*.py",
 "ports/**/*.py",
 "py/**/*.py",
 "tools/**/*.py",
 "tests/**/*.py",
]

EXCLUSIONS = [
 # STM32 build includes generated Python code.
 "ports/*/build*",
 # gitignore in ports/unix ignores *.py, so also do it here.
 "ports/unix/*.py",
 # not real python files
 "tests/**/repl_*.py",
 # needs careful attention before applying automatic formatting
 "tests/basics/*.py",
]

# Path to repo top-level dir.
TOP = os.path.abspath(os.path.join(os.path.dirname(__file__), ".."))

UNCRUSTIFY_CFG = os.path.join(TOP, "tools/uncrustify.cfg")

C_EXTS = (
 ".c",
 ".h",
)
PY_EXTS = (".py",)


def list_files(paths, exclusions=None, prefix=""):
 files = set()
 for pattern in paths:
 files.update(glob.glob(os.path.join(prefix, pattern), recursive=True))
 for pattern in exclusions or []:
 files.difference_update(glob.fnmatch.filter(files, os.path.join(prefix, pattern)))
 return sorted(files)


def fixup_c(filename):
 # Read file.
 with open(filename) as f:
 lines = f.readlines()

 # Write out file with fixups.
 with open(filename, "w", newline="") as f:
 dedent_stack = []
 while lines:
 # Get next line.
 l = lines.pop(0)

 # Dedent #'s to match indent of following line (not previous line).
 m = re.match(r"( +)#(if |ifdef |ifndef |elif |else|endif)", l)
 if m:
 indent = len(m.group(1))
 directive = m.group(2)
 if directive in ("if ", "ifdef ", "ifndef "):
 l_next = lines[0]
 indent_next = len(re.match(r"( *)", l_next).group(1))
 if indent - 4 == indent_next and re.match(r" +(} else |case )", l_next):
 # This #-line (and all associated ones) needs dedenting by 4 spaces.
 l = l[4:]
 dedent_stack.append(indent - 4)
 else:
 # This #-line does not need dedenting.
 dedent_stack.append(-1)
 else:
 if dedent_stack[-1] >= 0:
 # This associated #-line needs dedenting to match the #if.
 indent_diff = indent - dedent_stack[-1]
 assert indent_diff >= 0
 l = l[indent_diff:]
 if directive == "endif":
 dedent_stack.pop()

 # Write out line.
 f.write(l)

 assert not dedent_stack, filename


def main():
 cmd_parser = argparse.ArgumentParser(description="Auto-format C and Python files.")
 cmd_parser.add_argument("-c", action="store_true", help="Format C code only")
 cmd_parser.add_argument("-p", action="store_true", help="Format Python code only")
 cmd_parser.add_argument("-v", action="store_true", help="Enable verbose output")
 cmd_parser.add_argument("files", nargs="*", help="Run on specific globs")
 args = cmd_parser.parse_args()

 # Setting only one of -c or -p disables the other. If both or neither are set, then do both.
 format_c = args.c or not args.p
 format_py = args.p or not args.c

 # Expand the globs passed on the command line, or use the default globs above.
 files = []
 if args.files:
 files = list_files(args.files)
 else:
 files = list_files(PATHS, EXCLUSIONS, TOP)

 # Extract files matching a specific language.
 def lang_files(exts):
 for file in files:
 if os.path.splitext(file)[1].lower() in exts:
 yield file

 # Run tool on N files at a time (to avoid making the command line too long).
 def batch(cmd, files, N=200):
 while True:
 file_args = list(itertools.islice(files, N))
 if not file_args:
 break
 subprocess.check_call(cmd + file_args)

 # Format C files with uncrustify.
 if format_c:
 command = ["uncrustify", "-c", UNCRUSTIFY_CFG, "-lC", "--no-backup"]
 if not args.v:
 command.append("-q")
 batch(command, lang_files(C_EXTS))
 for file in lang_files(C_EXTS):
 fixup_c(file)

 # Format Python files with black.
 if format_py:
 command = ["black", "--fast", "--line-length=99"]
 if args.v:
 command.append("-v")
 else:
 command.append("-q")
 batch(command, lang_files(PY_EXTS))


if __name__ == "__main__":
 main()