#!/usr/bin/python3

"""Grab list of bus from Forgejo and use it to make a line graph."""

import configparser
import json
import os
import sys
import typing
from datetime import datetime, timezone

import requests

config = configparser.ConfigParser()

config_file_path = os.path.expanduser(
    os.path.join(os.getenv("XDG_CONFIG_HOME", "~/.config"), "bug-chart", "config")
)
assert os.path.exists(config_file_path)
config.read(os.path.expanduser(config_file_path))

Bug = dict[str, typing.Any]
CallParams = dict[str, str | int]

hostname = config.get("forgejo", "hostname")
token = config.get("forgejo", "token")
url = f"https://{hostname}/api/v1/repos/issues/search"


def download_bugs(state: str) -> list[Bug]:
    """Get all bugs from forgejo."""
    all_bugs: list[Bug] = []
    page = 0
    headers = {"Authorization": "token " + token}
    while bugs := requests.get(
        url,
        headers=headers,
        params=typing.cast(CallParams, {"state": state, "page": page}),
    ).json():
        if isinstance(bugs, dict):
            print(bugs)
            sys.exit(1)

        assert isinstance(bugs, list)
        all_bugs += bugs
        page += 1

    return all_bugs


def get_all_bugs(refresh: bool = False) -> list[Bug]:
    """Get all bugs."""
    filename = config.get("output", "cache")
    if not refresh and os.path.exists(filename):
        with open(filename) as fh:
            return typing.cast(list[Bug], json.load(fh))

    all_bugs = download_bugs("open") + download_bugs("closed")
    with open(filename, "w") as out:
        json.dump(all_bugs, out, indent=2)

    return all_bugs


def parse_date(date_str: str | None) -> datetime | None:
    """Parse a date string with timezone information."""
    if date_str is None:
        return None

    fmt = "%Y-%m-%dT%H:%M:%SZ" if date_str.endswith("Z") else "%Y-%m-%dT%H:%M:%S%z"
    return datetime.strptime(date_str, fmt).astimezone(timezone.utc)


def count_open_bugs(bug_reports: list[Bug]) -> list[tuple[str, int]]:
    """Count the number of open bugs for each date based on a list of bug reports."""
    dates: list[tuple[datetime, int]] = []

    # Process each bug report
    seen: set[int] = set()
    for report in bug_reports:
        if report["id"] in seen:
            continue
        seen.add(report["id"])
        open_date = parse_date(report["created_at"])
        assert open_date
        dates.append((open_date, 1))

        close_date = parse_date(report["closed_at"])
        if close_date:
            dates.append((close_date, -1))

    dates.sort()
    bug_count = 0
    open_bugs_over_time = []
    for dt, delta in dates:
        bug_count += delta
        iso_date = dt.isoformat()
        open_bugs_over_time.append((iso_date, bug_count))

    return open_bugs_over_time


def main() -> None:
    """Grab bug reports and generate chart."""
    refresh = len(sys.argv) > 1 and sys.argv[1] == "--refresh"
    bug_reports = get_all_bugs(refresh)

    open_bugs_over_time = count_open_bugs(bug_reports)
    json_data = json.dumps(open_bugs_over_time)

    script_dir = os.path.dirname(os.path.abspath(__file__))
    template_path = os.path.join(script_dir, "template.html")
    with open(template_path, "r") as fh:
        template_html = fh.read()
    dest = config.get("output", "dest")
    with open(dest, "w") as out:
        out.write(template_html.replace("jsonData = []", "jsonData = " + json_data))


if __name__ == "__main__":
    main()