import type { AggregatedReview, Finding, ReviewSeverity } from "./types.ts";

const SEVERITY_ORDER: ReviewSeverity[] = ["error", "warning", "nit"];

const SEVERITY_LABEL: Record<ReviewSeverity, string> = {
  error: "Errors",
  warning: "Warnings",
  nit: "Nits",
};

const SEVERITY_EMOJI: Record<ReviewSeverity, string> = {
  error: "🔴",
  warning: "🟡",
  nit: "🔵",
};

function renderGroup(severity: ReviewSeverity, findings: Finding[]): string {
  const items = findings.map(
    (f) => `**\`${f.filename}\`** line ${f.line}\n> ${f.comment}`,
  );
  return `### ${SEVERITY_EMOJI[severity]} ${SEVERITY_LABEL[severity]} (${findings.length})\n\n${items.join("\n\n")}`;
}

export function formatReview(
  review: AggregatedReview,
  files: string[],
  model: string,
): string {
  console.log(
    `Formatting review for ${files.length} file${files.length === 1 ? "" : "s"} with model ${model}...`,
  );
  const parts: string[] = [];

  parts.push(
    `## 🤖 shockbot review\n\n> Reviewed ${files.length} file${files.length === 1 ? "" : "s"} using \`${model}\``,
  );

  // Summary section — join per-chunk summaries
  const summaries = review.summaries.filter(Boolean);
  if (summaries.length > 0) {
    parts.push(`**Summary**\n\n${summaries.join("\n\n")}`);
  }

  // Group findings by severity
  const grouped = new Map<ReviewSeverity, Finding[]>();
  for (const severity of SEVERITY_ORDER) grouped.set(severity, []);
  for (const finding of review.findings) {
    grouped.get(finding.severity)?.push(finding);
  }

  const hasFindings = review.findings.length > 0;
  if (hasFindings) {
    for (const severity of SEVERITY_ORDER) {
      const group = grouped.get(severity)!;
      if (group.length > 0) parts.push(renderGroup(severity, group));
    }
  } else {
    parts.push("No issues found. ✅");
  }

  const timestamp = new Date().toISOString();
  parts.push(`---\n\n<sub>shockbot · \`${model}\` · ${timestamp}</sub>`);

  return parts.join("\n\n---\n\n");
}