#!/usr/bin/python3

import argparse
from datetime import datetime
import os
import re
import subprocess
import sys

def format_date(timestamp):
    date_to_format = datetime.utcfromtimestamp(timestamp)
    delta = datetime.utcnow() - date_to_format

    output = date_to_format.strftime('%Y-%m-%d %H:%M')
    if delta.days > 1:
        output += ' ({} days ago)'.format(delta.days)
    elif delta.days == 1:
        output += ' (yesterday)'

    return output

parser = argparse.ArgumentParser(description="Review DSA/DLA needed queues")
parser.add_argument('--lts', action='store_true',
                    help='Review dla-needed.txt instead of dsa-needed.txt')
parser.add_argument('-v', '--verbose', action='store_true',
                    help='Review dla-needed.txt instead of dsa-needed.txt')
parser.add_argument('--sort-by', default='last-update',
                    help='Sort by last-update (default) or by claimed-date')
parser.add_argument('--skip-unclaimed', action='store_true',
                    help='Skip unclaimed packages in the review')
args = parser.parse_args()

if args.lts:
    dsa_dla_needed = 'data/dla-needed.txt'
else:
    dsa_dla_needed = 'data/dsa-needed.txt'

if args.sort_by not in ('last-update', 'claimed-date'):
    sys.stderr.write('ERROR: usage: --sort-by={last-update,claimed-date}\n')
    sys.exit(1)

if not os.path.exists(dsa_dla_needed):
    sys.stderr.write("ERROR: {} not found\n".format(dsa_dla_needed))
    sys.exit(1)

if not os.path.exists(".git"):
    sys.stderr.write("ERROR: works only in a git checkout\n")
    sys.exit(1)

process = subprocess.Popen(["git", "blame", "--line-porcelain", "--",
                            dsa_dla_needed], stdout=subprocess.PIPE)
context = {}
in_preamble = True
all_entries = []
entry = None
for line in process.stdout:
    line = line.decode('utf-8')
    res = re.search(r'^([0-9a-f]{40}) \d+', line)
    if res:
        context['commit'] = res.group(1)
    if line.startswith('author '):
        context['author'] = line.strip().split()[1]
    elif line.startswith('author-time '):
        context['author-time'] = int(line.strip().split()[1])
    elif line.startswith('summary '):
        context['summary'] = line.strip().split(maxsplit=1)[1]
    elif line.startswith("\t"):
        line = line[1:]
        if line.startswith("--"):
            in_preamble = False
            entry = None
        elif in_preamble:
            continue
        elif line[0] == ' ' or line[0] == "\t":
            entry['note'] += line
            if context['author-time'] > entry['last-update']:
                entry['last-update'] = context['author-time']
                entry['last-update-author'] = context['author']
                entry['last-update-summary'] = context['summary']
                entry['last-update-commit'] = context['commit']
        else:
            res = re.match(r'^(\S+)(?:\s+\((.*)\)\s*)?$', line)
            entry = {
                'pkg': res.group(1),
                'claimed-by': res.group(2),
                'claimed-date': context['author-time'],
                'last-update': context['author-time'],
                'last-update-author': context['author'],
                'last-update-summary': context['summary'],
                'last-update-commit': context['commit'],
                'author': context['author'],
                'note': '',
            }
            all_entries.append(entry)

retcode = process.wait()
if retcode != 0:
    sys.stderr.write("WARNING: git blame returned error code {}\n".format(retcode))

all_entries.sort(key=lambda x: x[args.sort_by])

for entry in all_entries:
    if args.skip_unclaimed and not entry['claimed-by']:
        continue
    print("Package: {}".format(entry['pkg']))
    if entry['claimed-by']:
        print("Claimed-By: {}".format(entry['claimed-by']))
        print("Claimed-Date: {}".format(format_date(entry['claimed-date'])))
    else:
        print("Unclaimed-Since: {}".format(format_date(entry['claimed-date'])))
    if entry['last-update'] > entry['claimed-date']:
        print("Last-Update: {}".format(format_date(entry['last-update'])))
    if not args.verbose:
        print("")
        continue
    print("Last-Update-Author: {}".format(entry['last-update-author']))
    print("Last-Update-Summary: {}".format(entry['last-update-summary']))
    print("Last-Update-Commit: {}".format(entry['last-update-commit']))
    if entry['note']:
        print("Notes:\n{}".format(entry['note']))
    else:
        print("")