#!/usr/bin/env python3

from argparse import ArgumentParser,Namespace,Action

GIT_CMD = ["git", "log",
           "--all", '--pretty=format:user:%aN%n%ct',
           "--reverse", "--raw", "--encoding=UTF-8",
           "--no-renames", "--no-show-signature"]
SCHEMA=[
'''
CREATE TABLE IF NOT EXISTS user (
    id INTEGER NOT NULL PRIMARY KEY,
    name TEXT UNIQUE
);
''',
'''
CREATE TABLE IF NOT EXISTS repo (
    id INTEGER NOT NULL PRIMARY KEY,
    path TEXT UNIQUE
);
''',
'''
CREATE TABLE IF NOT EXISTS file (
    id INTEGER NOT NULL PRIMARY KEY,
    path TEXT UNIQUE
);
''',
'''
CREATE TABLE IF NOT EXISTS change (
    time DATETIME NOT NULL,
   	user_id INTEGER NOT NULL,
	action TEXT NOT NULL,
	repo_id INTEGER NOT NULL,
    file_id INTEGER NOT NULL,
    UNIQUE(time,user_id,repo_id,file_id,action)
    FOREIGN KEY(user_id) REFERENCES user(id)
    FOREIGN KEY(repo_id) REFERENCES repo(id)
    FOREIGN KEY(file_id) REFERENCES file(id)
);
''',
'''
CREATE TABLE IF NOT EXISTS log (
    id INTEGER NOT NULL PRIMARY KEY,
    type TEXT,
    time DATETIME DEFAULT CURRENT_TIMESTAMP,
    repo TEXT,
    message TEXT
);
''',
]

STMT_SELECT='''
SELECT time,user.name as user,action,repo.path as repo, file.path as file FROM change
LEFT JOIN user ON user.id = change.user_id
LEFT JOIN repo ON repo.id = change.repo_id
LEFT JOIN file ON file.id = change.file_id
'''

def main():
    p = parser()
    args = p.parse_args()
    import sys
    sys.exit(args.func(args) or 0)

def parser():
    p = ArgumentParser()
    p.add_argument('-d','--debug', action='store_true')
    p.set_defaults(func=lambda x: p.print_help())
    sub = p.add_subparsers()
    p_render = sub.add_parser('render')
    p_render.set_defaults(func=render)
    p_render.add_argument('--gource', default='gource')
    p_join = sub.add_parser('gitjoin')
    p_join.set_defaults(func=gitjoin)
    p_join.add_argument('source')
    p_join.add_argument('output')
    p_join.add_argument('-p','--prefix')
    p_select = sub.add_parser('select')
    p_select.add_argument('output')
    p_select.add_argument('--repo-like', default=None, type=str)
    p_select.add_argument('--file-like', default=None, type=str)
    p_select.add_argument('--user-like', default=None, type=str)
    p_select.add_argument('--user-regex', default=None, type=str)
    p_select.add_argument('--user-mapping', default={}, action=StoreDictKeyPair)
    p_select.add_argument('--user-file', default={}, action=YamlDict)
    p_select.set_defaults(func=select)
    return p

class StoreDictKeyPair(Action):
    def __call__(self, parser, namespace, values, option_string=None):
        my_dict = {}
        for kv in values.split(","):
            k,v = kv.split("=")
            my_dict[k] = v
        setattr(namespace, self.dest, my_dict)

class YamlDict(Action):
     def __call__(self, parser, namespace, values, option_string=None):
        import yaml
        with open(values) as fd:
            my_dict = yaml.safe_load(fd)
        assert isinstance(my_dict, dict)
        for k,v in my_dict.items():
            assert isinstance(k, str)
            assert isinstance(v, str)
        setattr(namespace, self.dest, my_dict)

def gitjoin(args: Namespace):
    import sqlite3
    import multiprocessing
    from functools import partial

    pool = multiprocessing.Pool()

    with sqlite3.connect(args.output) as conn:
        db = conn.cursor()
        for STMT in SCHEMA:
            db.execute(STMT)
        conn.commit()

        i = 0
        for fp,gitlog in pool.imap_unordered(get_gitlog, gitwalk_rec(args.source)):
            if fp == None:
                continue
            i += 1
            print(i,fp)
            p = fp[len(args.source):]

            list(map(partial(sqlite_insert, p=p, db=db, args=args), gitlog))
            if (i%10) == 0:
                conn.commit()
            # return  
        conn.commit()
        db.execute('VACUUM')
        conn.commit()

def get_gitlog(fp: str):
    import subprocess
    proc = subprocess.run(GIT_CMD, cwd=fp, stdout=subprocess.PIPE)
    gitlog = proc.stdout.decode(errors='ignore')
    if not proc.returncode == 0:
        return fp,[GitLogException(gitlog)]
    return fp,list(gource_format(gitlog))

class GitLogException(Exception):
    pass

def sqlite_insert(l: tuple, p=None, db=None, args=None):
    if isinstance(l, BaseException):
        if args.debug:
            db.execute('INSERT INTO log(type,repo,message) VALUES(?,?,?);', (l.__class__.__name__,p,str(l)))
        return

    fp = l[3].lstrip('/')
    db.execute('INSERT OR IGNORE INTO user(name) VALUES (?) RETURNING id', (l[1],))
    user_id = db.execute('SELECT id FROM user WHERE name=?', (l[1],)).fetchone()[0]
    # print("user:", user_id)
    db.execute('INSERT OR IGNORE INTO repo(path) VALUES (?) RETURNING id', (p,))
    repo_id = db.execute('SELECT id FROM repo WHERE path=?', (p,)).fetchone()[0]
    # print("repo:",repo_id)
    db.execute('INSERT OR IGNORE INTO file(path) VALUES (?) RETURNING id', (fp,))
    file_id = db.execute('SELECT id FROM file WHERE path=?', (fp,)).fetchone()[0]
    # print("file:",file_id)
    db.execute("INSERT OR IGNORE INTO change VALUES (@time,@user_id,@action,@repo_id,@file_id)", {
        'time': int(l[0]),
        'user_id': user_id,
        'action': l[2],
        'repo_id': repo_id,
        'file_id': file_id,
    })

def gource_format(inp: str):
    import subprocess
    GOURCE_CMD = ["gource", "--log-format", "git", "--output-custom-log", "-", "-"]
    with subprocess.Popen(GOURCE_CMD, stdout=subprocess.PIPE, stdin=subprocess.PIPE) as proc:
        out, err = proc.communicate(input=inp.encode())
        if proc.returncode != 0:
            yield GourceException(inp)
            return
    for l in out.decode().splitlines():
        ls = l.split('|')
        if len(ls) != 4:
            yield GourceDecodeException(str(ls))
            continue
        yield tuple(ls)
    # sed "s, \([ACDMRTU]\)\t, \1\t$REL/," | gource  --log-format git --output-custom-log - -

class GourceException(Exception):
    pass

class GourceDecodeException(Exception):
    pass

def gitwalk_rec(root: str):
    import os
    import random
    if not os.path.isdir(root):
        return
    if root.endswith('.git'):
        yield root
    else:
        ls = os.listdir(root)
        random.shuffle(ls)
        for d in ls:
            dj = os.path.join(root,d)
            for p in gitwalk_rec(dj):
                yield p

def select(args: Namespace):
    import sqlite3
    import os
    with sqlite3.connect(args.output) as db:
        import re    
        def regexp(y, x, search=re.search):
            return 1 if search(y, x, flags=re.IGNORECASE) else 0
        db.create_function('regexp', 2, regexp)

        STMT = STMT_SELECT
        ARGS = []
        WHERE_VERB = "WHERE"
        if args.user_regex:
            STMT += " "+WHERE_VERB+" user.name REGEXP ? "
            ARGS.append(args.user_regex)
            WHERE_VERB = "AND"
        if args.user_like:
            STMT += " "+WHERE_VERB+" user.name LIKE ? "
            ARGS.append(args.user_like)
            WHERE_VERB = "AND"
        if args.repo_like:
            STMT += " "+WHERE_VERB+" repo.path LIKE ? "
            ARGS.append(args.repo_like)
            WHERE_VERB = "AND"
        if args.file_like:
            STMT += " "+WHERE_VERB+" file.path LIKE ? "
            ARGS.append(args.file_like)
            WHERE_VERB = "AND"
        for i in db.execute(STMT + " ORDER BY time ASC", ARGS):
            # print(i)
            username = i[1]
            for k,v in args.user_mapping.items():
                if username == k:
                    username = v
                    break
            for k,v in args.user_file.items():
                if username == k:
                    username = v
                    break

            path = os.path.join(i[3],i[4])
            print('|'.join((str(i[0]),username,i[2],path)))

def render(args: Namespace):
    print(args)

if __name__=='__main__':
    main()