#!/usr/bin/env python3
"""GitHub Actions adapter for openapi_breaking_diff.py.

Writes a Markdown step summary, emits workflow annotations, and preserves the
CLI exit contract: 0=no supported breaking findings, 2=findings, 1=input error.
"""
from __future__ import annotations

import argparse
import json
import os
import sys
from pathlib import Path
from typing import Iterable

from openapi_breaking_diff import compare, load, markdown


def escape_command(value: str) -> str:
    return (
        value.replace("%", "%25")
        .replace("\r", "%0D")
        .replace("\n", "%0A")
        .replace(":", "%3A")
        .replace(",", "%2C")
    )


def annotations(findings: Iterable[dict[str, str]]) -> list[str]:
    rows = []
    for finding in findings:
        title = escape_command("OpenAPI breaking change: " + finding["change"])
        message = escape_command(finding["location"] + " — " + finding["detail"] )
        rows.append(f"::error title={title}::{message}")
    return rows


def write_summary(report: str, destination: str | None) -> None:
    if not destination:
        return
    path = Path(destination)
    path.parent.mkdir(parents=True, exist_ok=True)
    with path.open("a", encoding="utf-8") as handle:
        handle.write(report)


def set_output(name: str, value: str, destination: str | None) -> None:
    if not destination:
        return
    path = Path(destination)
    path.parent.mkdir(parents=True, exist_ok=True)
    delimiter = "OPENAPI_DIFF_OUTPUT"
    with path.open("a", encoding="utf-8") as handle:
        handle.write(f"{name}<<{delimiter}\n{value}\n{delimiter}\n")


def main() -> int:
    parser = argparse.ArgumentParser(description="Emit GitHub Actions annotations for OpenAPI breaking findings.")
    parser.add_argument("old", help="Baseline OpenAPI JSON file")
    parser.add_argument("new", help="Proposed OpenAPI JSON file")
    parser.add_argument("--report", default="openapi-breaking-report.md", help="Markdown report path")
    parser.add_argument("--json-report", help="Optional machine-readable report path")
    parser.add_argument("--allow-breaking", action="store_true", help="Do not fail when findings exist")
    args = parser.parse_args()

    try:
        findings = compare(load(args.old), load(args.new))
    except (OSError, json.JSONDecodeError, ValueError) as exc:
        print(f"::error title=OpenAPI diff input error::{escape_command(str(exc))}")
        return 1

    report = markdown(findings, args.old, args.new)
    Path(args.report).write_text(report, encoding="utf-8")
    if args.json_report:
        Path(args.json_report).write_text(
            json.dumps({"breaking_count": len(findings), "findings": findings}, indent=2) + "\n",
            encoding="utf-8",
        )

    for line in annotations(findings):
        print(line)
    if not findings:
        print("::notice title=OpenAPI compatibility check::No supported breaking changes detected")

    write_summary(report, os.environ.get("GITHUB_STEP_SUMMARY"))
    set_output("breaking_count", str(len(findings)), os.environ.get("GITHUB_OUTPUT"))
    set_output("report_path", args.report, os.environ.get("GITHUB_OUTPUT"))
    return 0 if args.allow_breaking or not findings else 2


if __name__ == "__main__":
    raise SystemExit(main())