import { readFileSync } from "node:fs";

/**
 * POST /api/rectification/agent as source text: route.ts (Supabase clients
 * and assembly) plus the branch modules it was split into
 * (TASK-rectification-code-split-20260926). A whole-source contract that held
 * on route.ts before the split holds on this concatenation after it, because
 * the code is the same code in more files. Slices between two anchors that
 * no longer sit in one file are rewritten per test.
 */
export const rectificationAgentRouteFiles = [
  "../src/app/api/rectification/agent/route.ts",
  "../src/lib/rectification-agentic/v9/agent-route-support.ts",
  "../src/lib/rectification-agentic/v9/agent-route-request.ts",
  "../src/lib/rectification-agentic/v9/agent-route-structured-choice.ts",
  "../src/lib/rectification-agentic/v9/agent-route-typed-message.ts",
  "../src/lib/rectification-agentic/v9/agent-route-agent-turn.ts",
  "../src/lib/rectification-agentic/v9/agent-route-billing.ts",
] as const;

export function readRectificationAgentRouteFile(relativePath: (typeof rectificationAgentRouteFiles)[number]): string {
  return readFileSync(new URL(relativePath, import.meta.url), "utf8");
}

export const rectificationAgentRouteSurface = rectificationAgentRouteFiles
  .map((relativePath) => readRectificationAgentRouteFile(relativePath))
  .join("\n");

/**
 * The typed-message fast path as it stood in route.ts between
 * `if (action === "message")` and `const requestTime`: the focus preflight,
 * the immediate-response exit, the unfocused classification and the deferred
 * replay. After the split the same code sits in agent-route-typed-message.ts,
 * the tail of route.ts, and the head of agent-route-agent-turn.ts.
 */
export function rectificationTypedMessageFastPath(): string {
  const route = readRectificationAgentRouteFile("../src/app/api/rectification/agent/route.ts");
  const agentTurn = readRectificationAgentRouteFile("../src/lib/rectification-agentic/v9/agent-route-agent-turn.ts");
  const routeStart = route.indexOf('if (action === "message")');
  const turnEnd = agentTurn.indexOf("const requestTime");
  if (routeStart < 0 || turnEnd < 0) throw new Error("typed-message fast path markers moved");
  return [
    readRectificationAgentRouteFile("../src/lib/rectification-agentic/v9/agent-route-typed-message.ts"),
    route.slice(routeStart),
    agentTurn.slice(0, turnEnd),
  ].join("\n");
}