from __future__ import annotations

import json
from collections.abc import Iterable
from dataclasses import dataclass


@dataclass(frozen=True)
class Finding:
    file: str
    hunk: str
    snippet: str
    message: str
    label: str

    def key(self) -> tuple[str, str, str, str, str]:
        return (self.file, self.hunk, self.snippet, self.message, self.label)


def dedupe_findings(findings: Iterable[Finding]) -> list[Finding]:
    seen = set()
    unique: list[Finding] = []
    for item in findings:
        key = item.key()
        if key in seen:
            continue
        seen.add(key)
        unique.append(item)
    return unique


def render_json(findings: Iterable[Finding]) -> str:
    payload = {"findings": [item.__dict__ for item in findings]}
    return json.dumps(payload, indent=2, sort_keys=True) + "\n"


def render_markdown(findings: Iterable[Finding]) -> str:
    items = list(findings)
    if not items:
        return "# Review Report\n\nNo findings.\n"

    lines: list[str] = ["# Review Report", ""]
    for idx, item in enumerate(items, start=1):
        lines.append(f"## Finding {idx}")
        lines.append(f"- File: {item.file}")
        lines.append(f"- Hunk: {item.hunk}")
        lines.append(f"- Label: {item.label}")
        lines.append("- Snippet:")
        lines.append("```")
        lines.append(item.snippet.rstrip())
        lines.append("```")
        lines.append("")
        lines.append(item.message)
        lines.append("")
    return "\n".join(lines).rstrip() + "\n"