import { type NextRequest, NextResponse } from "next/server";
import { prisma } from "@/lib/prisma";
import { errorResponse, requireRole, ApiError } from "@/lib/api";
import { readFileBytes } from "@/lib/files";
import {
  renderProjectTravelers,
  type OperationCardData,
  type PartCoverData,
} from "@/lib/pdf";

/**
 * Admin-only. Bulk traveler PDF for an entire project — one megafile
 * containing every part's cover + drawings + op cards, prefixed with a
 * project-level summary sheet.
 *
 * Query params:
 *   ?scope=all        (default) every part with at least one operation
 *   ?scope=incomplete only parts that still have pending / partial /
 *                     in_progress / qc_failed ops (i.e. what's left to run)
 *
 * Parts with zero operations are always skipped — they'd render an empty
 * card anyway. Drawings are inlined best-effort (missing files are logged
 * and the PDF still renders).
 */
export async function GET(req: NextRequest, ctx: { params: Promise<{ id: string }> }) {
  try {
    await requireRole("admin");
    const { id } = await ctx.params;
    const scope = (new URL(req.url).searchParams.get("scope") ?? "all").toLowerCase();
    if (scope !== "all" && scope !== "incomplete") {
      throw new ApiError(400, "bad_scope", "scope must be 'all' or 'incomplete'");
    }

    const project = await prisma.project.findUnique({
      where: { id },
      select: { id: true, code: true, name: true, customerCode: true, dueDate: true },
    });
    if (!project) throw new ApiError(404, "not_found", "Project not found");

    const parts = await prisma.part.findMany({
      where: {
        assembly: { projectId: id },
        ...(scope === "incomplete"
          ? {
              operations: {
                some: {
                  status: { in: ["pending", "partial", "in_progress", "qc_failed"] },
                },
              },
            }
          : {}),
      },
      orderBy: [{ assembly: { code: "asc" } }, { code: "asc" }],
      include: {
        assembly: {
          include: {
            project: { select: { code: true, name: true } },
            drawingFile: { select: { path: true, originalName: true } },
          },
        },
        stepFile: { select: { originalName: true, sizeBytes: true, sha256: true } },
        drawingFile: {
          select: { originalName: true, sizeBytes: true, sha256: true, path: true },
        },
        cutFile: { select: { originalName: true, sizeBytes: true, sha256: true } },
        operations: {
          orderBy: { sequence: "asc" },
          include: { machine: { select: { name: true, kind: true } } },
        },
      },
    });

    const eligible = parts.filter((p) => p.operations.length > 0);
    if (eligible.length === 0) {
      throw new ApiError(
        400,
        "no_parts",
        scope === "incomplete"
          ? "No parts with outstanding operations in this project"
          : "No parts with operations in this project",
      );
    }

    const bundles = await Promise.all(
      eligible.map(async (part) => {
        const projectHead = { code: part.assembly.project.code, name: part.assembly.project.name };
        const assembly = {
          code: part.assembly.code,
          name: part.assembly.name,
          qty: part.assembly.qty,
        };
        const partHeader = {
          code: part.code,
          name: part.name,
          material: part.material,
          qty: part.qty,
        };

        const drawingPdfBytes = await tryReadPdf(part.drawingFile?.path ?? null);
        const assemblyDrawingPdfBytes = await tryReadPdf(part.assembly.drawingFile?.path ?? null);

        const cover: PartCoverData = {
          project: projectHead,
          assembly,
          part: { ...partHeader, notes: part.notes },
          files: [
            { label: "STEP / 3D", file: part.stepFile },
            { label: "Drawing PDF", file: part.drawingFile },
            { label: "Cut file", file: part.cutFile },
          ],
          operations: part.operations.map((op) => ({
            sequence: op.sequence,
            name: op.name,
            kind: op.kind,
            machineName: op.machine?.name ?? null,
            qcRequired: op.qcRequired,
            qrToken: op.qrToken,
            unitsCompleted: op.unitsCompleted,
            status: op.status,
          })),
        };

        const cards: OperationCardData[] = part.operations.map((op) => ({
          project: projectHead,
          assembly,
          part: partHeader,
          operation: {
            id: op.id,
            sequence: op.sequence,
            name: op.name,
            kind: op.kind,
            qrToken: op.qrToken,
            machineName: op.machine?.name ?? null,
            machineKind: op.machine?.kind ?? null,
            settings: op.settings,
            materialNotes: op.materialNotes,
            instructions: op.instructions,
            qcRequired: op.qcRequired,
            plannedMinutes: op.plannedMinutes,
            plannedUnits: op.plannedUnits,
            unitsCompleted: op.unitsCompleted,
            status: op.status,
          },
        }));

        return { cover, cards, drawingPdfBytes, assemblyDrawingPdfBytes };
      }),
    );

    const pdf = await renderProjectTravelers({
      project: {
        code: project.code,
        name: project.name,
        customerCode: project.customerCode,
        dueDate: project.dueDate,
      },
      bundles,
    });
    const suffix = scope === "incomplete" ? "-incomplete" : "";
    const safeName = `${project.code}${suffix}-travelers.pdf`.replace(/[^A-Za-z0-9._-]/g, "_");

    return new NextResponse(pdf as unknown as BodyInit, {
      status: 200,
      headers: {
        "Content-Type": "application/pdf",
        "Content-Disposition": `inline; filename="${safeName}"`,
        "Cache-Control": "private, no-store",
      },
    });
  } catch (err) {
    return errorResponse(err);
  }
}

async function tryReadPdf(path: string | null): Promise<Uint8Array | null> {
  if (!path) return null;
  try {
    const buf = await readFileBytes(path);
    return new Uint8Array(buf);
  } catch (err) {
    console.warn("[projects/travelers.pdf] could not read drawing file", { path, err });
    return null;
  }
}