#!/usr/bin/env python3
"""Fix S112 (try-except-continue) by logging the exception before continuing."""

from __future__ import annotations

import json
import re
import subprocess
import sys
from pathlib import Path

LOG_LINE = 'logging.getLogger(__name__).warning("swallowed exception", exc_info=True)'

SAME_LINE_CONTINUE = re.compile(
    r"^(?P<indent>[ \t]*)except\b(?P<expr>[^:\n]*):\s*continue\s*(?:#.*)?$",
    re.MULTILINE,
)


def ensure_import(text: str, module: str) -> str:
    if re.search(rf"(?:^|\n)import\s+{re.escape(module)}(?:\s|$)", text):
        return text
    if re.search(rf"(?:^|\n)from\s+{re.escape(module)}\s+import", text):
        return text
    lines = text.splitlines(keepends=True)
    insert = 0
    paren = 0
    for i, ln in enumerate(lines):
        paren += ln.count("(") - ln.count(")")
        if ln.startswith("#!/") or ln.startswith("# -*-") or ln.startswith("# coding"):
            insert = i + 1
            continue
        if ln.startswith("from __future__ import"):
            insert = i + 1
            continue
        if paren == 0 and (ln.startswith("import ") or ln.startswith("from ")):
            insert = i + 1
    if insert == len(lines) and lines and not lines[-1].endswith("\n"):
        lines.append("\n")
    lines.insert(insert, f"import {module}\n")
    return "".join(lines)


def fix_file(path: Path) -> int:
    text = path.read_text()
    orig = text

    # same-line: except X: continue
    text = SAME_LINE_CONTINUE.sub(
        lambda m: (
            f"{m.group('indent')}except {m.group('expr').strip()}:\n"
            f"{m.group('indent')}    {LOG_LINE}\n"
            f"{m.group('indent')}    continue"
        ),
        text,
    )

    if text != orig:
        text = ensure_import(text, "logging")
        path.write_text(text)
        return 1
    return 0


if __name__ == "__main__":
    proc = subprocess.run(
        [
            sys.executable,
            "-m",
            "ruff",
            "check",
            "--select",
            "S112",
            "--output-format",
            "json",
            "app/",
        ],
        capture_output=True,
        text=True,
    )
    errors = json.loads(proc.stdout or "[]")
    by_file: dict[str, list[int]] = {}
    for e in errors:
        by_file.setdefault(e["filename"], []).append(e["location"]["row"])

    total_files = 0
    for fn, rows in by_file.items():
        path = Path(fn)
        text = path.read_text()
        orig = text
        text = ensure_import(text, "logging")
        lines = text.splitlines(keepends=True)

        for row in sorted(rows, reverse=True):
            if row < 1 or row > len(lines):
                continue
            idx = row - 1
            line = lines[idx]
            m = SAME_LINE_CONTINUE.match(line)
            if m:
                indent = m.group("indent")
                expr = m.group("expr").strip()
                new_lines = [
                    f"{indent}except {expr}:\n",
                    f"{indent}    {LOG_LINE}\n",
                    f"{indent}    continue\n",
                ]
                lines[idx : idx + 1] = new_lines
                continue
            # multiline: find next continue
            j = idx + 1
            while j < len(lines):
                content = lines[j].strip()
                if content == "" or content.startswith("#"):
                    j += 1
                    continue
                if (
                    content == "continue"
                    or content.startswith("continue ")
                    or content.startswith("continue\t")
                ):
                    indent = len(lines[j]) - len(lines[j].lstrip())
                    lines[j] = " " * indent + LOG_LINE + "\n" + " " * indent + "continue\n"
                    break
                break

        text = "".join(lines)
        if text != orig:
            path.write_text(text)
            total_files += 1

    print(f"S112: fixed {len(errors)} errors in {total_files} files")