import "server-only";
import { createHash, randomBytes, randomUUID } from "node:crypto";
import { NextRequest, NextResponse } from "next/server";
import { z } from "zod";
import { admin, required, user } from "./supabase";
import { accountProfile } from "./profile";
import { requestOrigin } from "./request-origin";
import { ServiceError } from "./service-error";
import {
  bugReportSchema,
  bugMessageSchema,
  type BugReportRecord,
  type BugReportView,
} from "../shared/bug-reports";
import { supportScreenshot } from "./support-images";
import { supportReady, syncBugAfterResponse } from "./support-sync";

type Dependencies = {
  jsonBody: (request: NextRequest) => Promise<unknown>;
  limit: (key: string, count: number, seconds: number) => Promise<void>;
};
export async function bugReportApi(
  request: NextRequest,
  path: string[],
  { jsonBody, limit }: Dependencies,
) {
  const db = admin(),
    account = await user();
  const profile = account ? await accountProfile(account) : null;
  const saved = request.cookies.get("mg_support")?.value;
  const secret = saved ?? randomBytes(32).toString("hex");
  const hash = createHash("sha256").update(secret).digest("hex");
  const respond = (body: unknown) => {
    const response = NextResponse.json(body, {
      headers: { "Cache-Control": "no-store" },
    });
    if (!saved)
      response.cookies.set("mg_support", secret, {
        httpOnly: true,
        sameSite: "lax",
        secure: requestOrigin(request, process.env.MINEGEO_URL).startsWith(
          "https:",
        ),
        path: "/",
        maxAge: 60 * 60 * 24 * 180,
      });
    return response;
  };
  const owns = (record: BugReportRecord) =>
    record.owner_id
      ? record.owner_id === account?.id
      : !!saved && record.access_hash === hash;
  async function owned(id: string) {
    const record = required(
      await db.from("bug_reports").select("*").eq("id", id).maybeSingle(),
    );
    if (!owns(record)) throw new ServiceError("Report not found", 404);
    return record;
  }
  async function view(record: BugReportRecord): Promise<BugReportView> {
    const messages = required(
      await db
        .from("bug_report_messages")
        .select("id,kind,body,author_name,delivered,created_at")
        .eq("report_id", record.id)
        .order("created_at", { ascending: false })
        .limit(200),
    ).reverse();
    const screenshot = record.screenshot_path
      ? required(
          await db.storage
            .from("minegeo-support")
            .createSignedUrl(record.screenshot_path, 600),
        ).signedUrl
      : null;
    return {
      id: record.id,
      title: record.title,
      description: record.description,
      page_path: record.page_path,
      state: record.state,
      linear_identifier: record.linear_identifier,
      glow_requested: record.glow_requested,
      created_at: record.created_at,
      screenshot,
      messages,
      isGuest: record.owner_id === null,
      authorAppearance: record.owner_id ? (profile ?? undefined) : undefined,
      canClaim: record.owner_id === null && !!account,
    };
  }
  if (path.length === 1 && request.method === "GET") {
    const rows = required(
      await db
        .from("bug_reports")
        .select("id,title,state,created_at,linear_identifier")
        .or(
          account
            ? `owner_id.eq.${account.id},and(owner_id.is.null,access_hash.eq.${hash})`
            : `and(owner_id.is.null,access_hash.eq.${hash})`,
        )
        .order("created_at", { ascending: false })
        .limit(50),
    );
    return respond({
      ready: supportReady(),
      signedIn: !!account,
      displayName: profile?.display_name ?? null,
      nameGlow: profile?.name_glow ?? false,
      reports: rows,
    });
  }
  if (request.method === "POST" && path.length === 1) {
    if (!saved)
      throw new ServiceError("Open support before sending a report", 409);
    const body = bugReportSchema.parse(await jsonBody(request));
    const lookup = await db
      .from("bug_reports")
      .select("*")
      .eq("client_id", body.clientId)
      .maybeSingle();
    if (lookup.error) required(lookup);
    let record = lookup.data;
    if (record && !owns(record))
      throw new ServiceError("Report not found", 404);
    if (!record) {
      if (!supportReady())
        throw new ServiceError(
          "Bug reporting is temporarily unavailable. Please try again later.",
          503,
        );
      const ip =
        request.headers.get("x-forwarded-for")?.split(",")[0].trim() ??
        "unknown";
      await limit(
        "support:create:" + createHash("sha256").update(ip).digest("hex"),
        20,
        3600,
      );
      await limit("support:create:" + hash, 5, 3600);
      const inserted = await db
        .from("bug_reports")
        .upsert(
          {
            id: randomUUID(),
            client_id: body.clientId,
            owner_id: account?.id ?? null,
            access_hash: hash,
            display_name:
              profile?.display_name ?? body.displayName ?? "Guest explorer",
            title: body.title,
            description: body.description,
            page_path: body.pagePath,
            screenshot_expected: body.screenshot,
          },
          { onConflict: "client_id", ignoreDuplicates: true },
        )
        .select("id");
      required(inserted);
      record = required(
        await db
          .from("bug_reports")
          .select("*")
          .eq("client_id", body.clientId)
          .single(),
      );
      if (!owns(record)) throw new ServiceError("Report not found", 404);
    }
    const upload =
      record.state === "draft" && record.screenshot_expected
        ? required(
            await db.storage
              .from("minegeo-support")
              .createSignedUploadUrl(`${record.id}/input`, { upsert: true }),
          ).signedUrl
        : null;
    return respond({ id: record.id, state: record.state, upload });
  }
  const id = z.string().uuid().parse(path[1]);
  const record = await owned(id);
  if (path.length === 2 && request.method === "GET") {
    if (record.state !== "draft") syncBugAfterResponse(id);
    return respond(await view(record));
  }
  if (path.length !== 3 || request.method !== "POST")
    return NextResponse.json({ error: "Not found" }, { status: 404 });
  if (path[2] === "submit") {
    if (record.state === "draft") {
      let screenshotPath: string | null = null;
      if (record.screenshot_expected) {
        const image = required(
          await db.storage.from("minegeo-support").download(`${id}/input`),
        );
        const normalized = await supportScreenshot(
          new Uint8Array(await image.arrayBuffer()),
        );
        screenshotPath = `${id}/screenshot.webp`;
        const uploaded = await db.storage
          .from("minegeo-support")
          .upload(screenshotPath, normalized, {
            contentType: "image/webp",
            upsert: false,
          });
        if (
          uploaded.error &&
          uploaded.error.message !== "The resource already exists"
        )
          throw new ServiceError(
            "Screenshot upload failed. Please try again.",
            503,
          );
      }
      // Stable initial message ID and conditional transition make submit retries safe.
      required(
        await db
          .from("bug_report_messages")
          .upsert(
            {
              id,
              report_id: id,
              kind: "user",
              body: record.description,
              author_name: record.display_name,
            },
            { onConflict: "id", ignoreDuplicates: true },
          )
          .select("id"),
      );
      required(
        await db
          .from("bug_reports")
          .update({
            state: "pending",
            screenshot_path: screenshotPath,
            updated_at: new Date().toISOString(),
          })
          .eq("id", id)
          .eq("state", "draft")
          .select("id"),
      );
    }
    syncBugAfterResponse(id);
    return respond(await view(await owned(id)));
  }
  if (path[2] === "messages") {
    if (record.state === "draft")
      throw new ServiceError("Submit this report before sending messages", 409);
    const body = bugMessageSchema.parse(await jsonBody(request));
    const existing = await db
      .from("bug_report_messages")
      .select("report_id,kind")
      .eq("report_id", id)
      .eq("client_id", body.clientId)
      .maybeSingle();
    if (existing.error) required(existing);
    if (
      existing.data &&
      (existing.data.report_id !== id || existing.data.kind !== "user")
    )
      throw new ServiceError("Invalid support message", 400);
    if (!existing.data) {
      await limit("support:message:" + hash, 30, 60);
      required(
        await db
          .from("bug_report_messages")
          .upsert(
            {
              client_id: body.clientId,
              report_id: id,
              kind: "user",
              body: body.text,
              author_name: profile?.display_name ?? record.display_name,
            },
            { onConflict: "report_id,client_id", ignoreDuplicates: true },
          )
          .select("id"),
      );
      const inserted = required(
        await db
          .from("bug_report_messages")
          .select("report_id,kind")
          .eq("report_id", id)
          .eq("client_id", body.clientId)
          .single(),
      );
      if (inserted.report_id !== id || inserted.kind !== "user")
        throw new ServiceError("Invalid support message", 400);
    }
    syncBugAfterResponse(id);
    return respond(await view(record));
  }
  if (path[2] === "claim") {
    if (!account) throw new ServiceError("Sign in to link this report", 401);
    required(
      await db.rpc("claim_bug_report", {
        p_report: id,
        p_hash: hash,
        p_owner: account.id,
      }),
    );
    return respond(await view(await owned(id)));
  }
  return NextResponse.json({ error: "Not found" }, { status: 404 });
}