"""阶段 4：汇总报告 + 落盘。

审查结论在阶段 3 已是结构化对象（`{summary, issues[]}`），
因此这里**不再**需要第二次 LLM 调用来抽取结构。
"""

import json
from datetime import datetime
from pathlib import Path

from .. import config
from ..findings import flatten_issues

_SUMMARY_SYSTEM = (
    "你是图纸审查负责人。请把下面各图框的审查意见汇总为一份结构化的审查报告："
    "先给整体结论，再按图框列出问题，最后给出整改建议。语言简洁、条目化。"
)


def format_finding(finding):
    """把一个 findings 元素渲染成给汇总 LLM 的文本块。"""
    lines = [f"【图框 {finding.get('frame')}（图幅 {finding.get('sheet')}）】"]
    summary = finding.get("summary")
    if summary:
        lines.append(str(summary))
    for issue in finding.get("issues") or []:
        tag = "确定性" if issue.get("source") == "deterministic" else "LLM"
        flag = "" if issue.get("verified", True) else "（未在证据中定位，仅供参考）"
        handle = issue.get("handle")
        where = f" handle={handle}" if handle else ""
        lines.append(
            f"- [{issue.get('severity', '?')}][{tag}] {issue.get('message', '')}{where}{flag}"
        )
    return "\n".join(lines)


def summarize(ctx, findings, log=print):
    """用 LLM 把各图框结论汇总为总报告。"""
    if not findings:
        return "未识别到可审查的图框，或所有图框均无有效包围盒。"

    report_input = "\n\n".join(format_finding(f) for f in findings)
    try:
        return ctx.llm.chat_text(_SUMMARY_SYSTEM, report_input)
    except Exception as exc:  # noqa: BLE001
        log(f"[汇总失败] {exc}")
        return report_input


def save_report(markdown, findings, plan, issues=None, log=print):
    """落盘 Markdown + JSON 报告，返回两个路径。

    `issues` 省略时从 findings 里拍平派生（供批注回写）。
    """
    if issues is None:
        issues = flatten_issues(findings)

    out_dir = Path(config.REPORT_DIR)
    out_dir.mkdir(parents=True, exist_ok=True)
    stamp = datetime.now().strftime("%Y%m%d_%H%M%S")
    md_path = out_dir / f"review_{stamp}.md"
    json_path = out_dir / f"review_{stamp}.json"

    md_path.write_text(markdown, encoding="utf-8")
    json_path.write_text(
        json.dumps(
            {
                "generated_at": stamp,
                "findings": findings,
                "issues": issues,
                "frames": plan.get("frames"),
            },
            ensure_ascii=False,
            indent=2,
        ),
        encoding="utf-8",
    )
    log(f"[报告] 已写入 {md_path} 与 {json_path}")
    return md_path, json_path