git_commit_date_editor.py

#!/usr/bin/env python3
import os
import subprocess
import sys
from dataclasses import dataclass
from datetime import datetime
from typing import List, Optional, Tuple


@dataclass
class CommitInfo:
    sha: str
    short_sha: str
    author_date: str
    committer_date: str
    subject: str


DATE_FORMAT_HINT = "YYYY-MM-DD HH:MM:SS"


def run_git(args: List[str], cwd: str, check: bool = True, env: Optional[dict] = None) -> subprocess.CompletedProcess:
    merged_env = os.environ.copy()
    if env:
        merged_env.update(env)
    return subprocess.run(
        ["git", *args],
        cwd=cwd,
        env=merged_env,
        text=True,
        capture_output=True,
        check=check,
    )


def is_git_repo(path: str) -> bool:
    try:
        result = run_git(["rev-parse", "--is-inside-work-tree"], cwd=path)
        return result.stdout.strip() == "true"
    except subprocess.CalledProcessError:
        return False


def ensure_clean_worktree(path: str) -> Tuple[bool, str]:
    result = run_git(["status", "--porcelain"], cwd=path, check=False)
    if result.returncode != 0:
        return False, result.stderr.strip() or "无法检查工作区状态"
    if result.stdout.strip():
        return False, "工作区存在未提交变更。请先提交或暂存，否则 rebase/amend 风险较高。"
    return True, ""


def get_commits(path: str, count: int = 30) -> List[CommitInfo]:
    fmt = "%H%x1f%h%x1f%ad%x1f%cd%x1f%s"
    result = run_git(
        [
            "log",
            f"--max-count={count}",
            f"--pretty=format:{fmt}",
            "--date=format:%Y-%m-%d %H:%M:%S",
        ],
        cwd=path,
    )
    commits: List[CommitInfo] = []
    for line in result.stdout.splitlines():
        parts = line.split("\x1f")
        if len(parts) != 5:
            continue
        commits.append(
            CommitInfo(
                sha=parts[0],
                short_sha=parts[1],
                author_date=parts[2],
                committer_date=parts[3],
                subject=parts[4],
            )
        )
    return commits


def prompt(msg: str) -> str:
    try:
        return input(msg).strip()
    except KeyboardInterrupt:
        print("\n已取消。")
        sys.exit(1)


def choose_repo_path() -> str:
    raw = prompt("Git 仓库路径（直接回车表示当前目录）: ")
    path = os.path.abspath(raw or os.getcwd())
    if not os.path.isdir(path):
        print(f"路径不存在: {path}")
        sys.exit(1)
    if not is_git_repo(path):
        print(f"不是 Git 仓库: {path}")
        sys.exit(1)
    return path


def choose_commit(commits: List[CommitInfo]) -> CommitInfo:
    if not commits:
        print("未找到任何 commit。")
        sys.exit(1)

    print("\n最近的提交：")
    print("-" * 100)
    for idx, c in enumerate(commits, start=1):
        print(f"[{idx:>2}] {c.short_sha} | A:{c.author_date} | C:{c.committer_date} | {c.subject}")
    print("-" * 100)

    while True:
        raw = prompt("请选择要修改的 commit 编号: ")
        if not raw.isdigit():
            print("请输入数字编号。")
            continue
        idx = int(raw)
        if 1 <= idx <= len(commits):
            return commits[idx - 1]
        print("编号超出范围。")


def parse_datetime_input(label: str, default_value: Optional[str] = None) -> str:
    suffix = f"（留空使用 {default_value}）" if default_value else ""
    while True:
        raw = prompt(f"请输入{label} {DATE_FORMAT_HINT} {suffix}: ")
        value = raw or default_value
        if not value:
            print("不能为空。")
            continue
        try:
            dt = datetime.strptime(value, "%Y-%m-%d %H:%M:%S")
            return dt.strftime("%Y-%m-%dT%H:%M:%S")
        except ValueError:
            print("日期格式错误，请按 YYYY-MM-DD HH:MM:SS 输入。")


def count_commits_from_head_to_target(path: str, sha: str) -> int:
    result = run_git(["rev-list", "--count", f"{sha}..HEAD"], cwd=path)
    return int(result.stdout.strip())


def amend_head_dates(path: str, author_dt: str, committer_dt: str) -> None:
    env = {"GIT_COMMITTER_DATE": committer_dt}
    run_git(["commit", "--amend", "--no-edit", f"--date={author_dt}"], cwd=path, env=env)


def rewrite_non_head_commit(path: str, target_sha: str, author_dt: str, committer_dt: str) -> None:
    ahead_count = count_commits_from_head_to_target(path, target_sha)
    if ahead_count <= 0:
        raise RuntimeError("目标 commit 不是 HEAD，计数却为 0，状态异常。")

    base = f"HEAD~{ahead_count + 1}"
    env = os.environ.copy()
    env["GIT_SEQUENCE_EDITOR"] = "sed -i.bak '1s/^pick /edit /'"

    try:
        subprocess.run(
            ["git", "rebase", "-i", base],
            cwd=path,
            env=env,
            text=True,
            capture_output=True,
            check=True,
        )
    except subprocess.CalledProcessError as e:
        msg = e.stderr.strip() or e.stdout.strip() or "interactive rebase 启动失败"
        raise RuntimeError(msg) from e

    try:
        amend_head_dates(path, author_dt, committer_dt)
        run_git(["rebase", "--continue"], cwd=path)
    except Exception:
        subprocess.run(["git", "rebase", "--abort"], cwd=path, text=True, capture_output=True)
        raise


def main() -> None:
    print("Git Commit 时间修改器")
    print("=" * 40)
    print("说明：只建议在未 push 到远端，且工作区干净时使用。")

    repo = choose_repo_path()
    clean, msg = ensure_clean_worktree(repo)
    if not clean:
        print(f"\n拒绝执行：{msg}")
        sys.exit(1)

    commits = get_commits(repo, count=30)
    target = choose_commit(commits)

    print("\n已选择：")
    print(f"SHA: {target.sha}")
    print(f"Subject: {target.subject}")
    print(f"当前 Author Date:    {target.author_date}")
    print(f"当前 Committer Date: {target.committer_date}")

    mode = prompt("\n是否同时修改 author/committer 时间？[Y/n]: ").lower() or "y"
    if mode == "n":
        print("当前版本仍要求输入两者时间，但你可以填相同或分别指定。")

    author_dt = parse_datetime_input("Author Date", target.author_date)
    committer_dt = parse_datetime_input("Committer Date", target.committer_date)

    print("\n即将执行：")
    print(f"仓库: {repo}")
    print(f"提交: {target.short_sha} {target.subject}")
    print(f"新 Author Date:    {author_dt}")
    print(f"新 Committer Date: {committer_dt}")
    print("注意：这会重写历史并改变该 commit 及其后续 commit 的 SHA。")

    confirm = prompt("确认继续？请输入 YES: ")
    if confirm != "YES":
        print("已取消。")
        sys.exit(0)

    try:
        head_sha = run_git(["rev-parse", "HEAD"], cwd=repo).stdout.strip()
        if target.sha == head_sha:
            amend_head_dates(repo, author_dt, committer_dt)
        else:
            rewrite_non_head_commit(repo, target.sha, author_dt, committer_dt)
    except subprocess.CalledProcessError as e:
        msg = e.stderr.strip() or e.stdout.strip() or str(e)
        print(f"\n执行失败：{msg}")
        sys.exit(1)
    except Exception as e:
        print(f"\n执行失败：{e}")
        sys.exit(1)

    print("\n修改完成。新的最近提交记录如下：\n")
    for c in get_commits(repo, count=10):
        print(f"{c.short_sha} | A:{c.author_date} | C:{c.committer_date} | {c.subject}")


if __name__ == "__main__":
    main()