// Analyze pass: extract requirements from prose with traceability hints.

import "server-only";
import { defaultGateway, chatJSON, type Message } from "../gateway";
import { loadPrompt } from "../prompts";
import type { DetectedRequirement } from "../../db/repo";

const reqsJsonSchema = {
  type: "object",
  additionalProperties: false,
  required: ["requirements"],
  properties: {
    requirements: {
      type: "array",
      items: {
        type: "object",
        additionalProperties: false,
        required: ["tag", "text"],
        properties: {
          tag: { type: "string", minLength: 1 },
          text: { type: "string", minLength: 1 },
          tracedToLabels: { type: "array", items: { type: "string" } },
          /// Optional concept the requirement is conceptually "about." Lets the
          /// requirement render a back-link to the term in TermDetail even when
          /// the term has no formalized block yet.
          linkedTermLabel: { type: "string" },
        },
      },
    },
  },
} as const;

export interface RequirementsResult {
  reqs: DetectedRequirement[];
  inputTokens: number;
  outputTokens: number;
  provider: string;
  model: string;
}

export async function analyzeRequirements(
  documentText: string,
  terms: Array<{ id: string; label: string; linkedBlockId: string | null }>
): Promise<RequirementsResult> {
  const prompt = loadPrompt("socrates/analyze-requirements.md");
  const gateway = defaultGateway();
  const userPayload =
    `Document:\n\n${documentText}\n\n---\n\n` +
    `Available term labels:\n${JSON.stringify(terms.map(t => t.label))}`;

  const messages: Message[] = [
    { role: "system", content: prompt },
    { role: "user", content: userPayload },
  ];

  const { value, result } = await chatJSON<{
    requirements?: Array<{
      tag?: string;
      text?: string;
      tracedToLabels?: string[];
      linkedTermLabel?: string;
    }>;
  }>(gateway, messages, {
    temperature: 0.2,
    maxTokens: 1500,
    jsonSchema: { name: "requirements", schema: reqsJsonSchema as Record<string, unknown> },
    jsonObjectMode: true,
    maxRepairs: 2,
  });

  // Map term labels → block ids via the term-to-block links + label → termId.
  const labelToBlock = new Map<string, string>();
  const labelToTermId = new Map<string, string>();
  for (const t of terms) {
    if (t.linkedBlockId) labelToBlock.set(t.label.toLowerCase(), t.linkedBlockId);
    labelToTermId.set(t.label.toLowerCase(), t.id);
  }

  const reqs: DetectedRequirement[] = [];
  for (const r of value?.requirements ?? []) {
    const tag = (r.tag ?? "").trim();
    const text = (r.text ?? "").trim();
    if (!tag || !text) continue;
    const blockIds = (r.tracedToLabels ?? [])
      .map(l => labelToBlock.get(l.toLowerCase()))
      .filter((id): id is string => Boolean(id));
    const linkedTermId = r.linkedTermLabel ? labelToTermId.get(r.linkedTermLabel.toLowerCase()) : undefined;
    reqs.push({
      tag,
      text,
      tracedToIds: blockIds,
      unsupported: blockIds.length === 0,
      linkedTermId: linkedTermId ?? null,
    });
  }

  return {
    reqs,
    inputTokens: result.inputTokens,
    outputTokens: result.outputTokens,
    provider: gateway.provider,
    model: gateway.model,
  };
}