#!/usr/bin/env python3

import os
import re
import subprocess
import tempfile

from aider import __version__


def get_base_version():
    # Parse current version like "0.64.2.dev" to get major.minor
    match = re.match(r"(\d+\.\d+)", __version__)
    if not match:
        raise ValueError(f"Could not parse version: {__version__}")
    return match.group(1) + ".0"


def run_git_log():
    base_ver = get_base_version()
    cmd = [
        "git",
        "log",
        "-p",
        f"v{base_ver}..HEAD",
        "--",
        "aider/",
        ":!aider/website/",
        ":!scripts/",
        ":!HISTORY.md",
    ]
    result = subprocess.run(cmd, capture_output=True, text=True)
    return result.stdout


def main():
    # Get the git log output
    diff_content = run_git_log()

    # Extract relevant portion of HISTORY.md
    base_ver = get_base_version()
    with open("HISTORY.md", "r") as f:
        history_content = f.read()

    # Find the section for this version
    version_header = f"### Aider v{base_ver}"
    start_idx = history_content.find("# Release history")
    if start_idx == -1:
        raise ValueError("Could not find start of release history")

    # Find where this version's section ends
    version_idx = history_content.find(version_header, start_idx)
    if version_idx == -1:
        raise ValueError(f"Could not find version header: {version_header}")
    
    # Find the next version header after this one
    next_version_idx = history_content.find("\n### Aider v", version_idx + len(version_header))
    if next_version_idx == -1:
        # No next version found, use the rest of the file
        relevant_history = history_content[start_idx:]
    else:
        # Extract just up to the next version
        relevant_history = history_content[start_idx:next_version_idx]

    # Save relevant portions to temporary files
    with tempfile.NamedTemporaryFile(mode="w", delete=False, suffix=".diff") as tmp_diff:
        tmp_diff.write(diff_content)
        diff_path = tmp_diff.name

    with tempfile.NamedTemporaryFile(mode="w", delete=False, suffix=".md") as tmp_hist:
        tmp_hist.write(relevant_history)
        hist_path = tmp_hist.name

    # Run blame to get aider percentage
    blame_result = subprocess.run(["python3", "scripts/blame.py"], capture_output=True, text=True)
    aider_line = blame_result.stdout.strip().split("\n")[-1]  # Get last line with percentage

    # Construct and run the aider command
    message = f"""
Update the history with changes shown in the diffs.
Describe actual user-facing changes, not every single commit that was made implementing them.
Don't edit or duplicate changes that have existing history entries, just add any new items not already listed.
Be sure to attribute changes to the proper .x version.
Changes in the .x-dev version should be listed under a "### main branch" heading

Also, add this as the last bullet under the "### main branch" section:
{aider_line}
"""  # noqa

    cmd = ["aider", hist_path, "--read", diff_path, "--msg", message, "--no-auto-commit"]
    subprocess.run(cmd)

    # Read back the updated history
    with open(hist_path, "r") as f:
        updated_history = f.read()

    # Splice the updated portion back into the full history
    full_history = history_content[:start_idx] + updated_history

    # Write back the full history
    with open("HISTORY.md", "w") as f:
        f.write(full_history)

    # Run update-docs.sh after aider
    subprocess.run(["scripts/update-docs.sh"])

    # Cleanup
    os.unlink(diff_path)
    os.unlink(hist_path)

    # Show git diff of HISTORY.md
    subprocess.run(["git", "diff", "HISTORY.md"])


if __name__ == "__main__":
    main()