import { NextResponse } from "next/server";
import { auth } from "@/app/(auth)/auth";
import { upsertSystemSetting } from "@/lib/db/queries";
import { readAgentPsdFonts } from "@/lib/agents/psd-font-settings";
import {
  AGENT_PSD_TEMPLATES_KEY,
  type AgentPsdTemplateMutationResponse,
  getEditableAgentPsdTemplateLayers,
  isAgentPsdTemplateReady,
  isAgentPsdTemplateRuntimeReady,
  isAgentPsdTextLayerSlot,
} from "@/lib/agents/psd-template-config";
import {
  repairAgentPsdTemplateAssetsIfNeeded,
  repairAgentPsdTemplateFontBindings,
} from "@/lib/agents/psd-template-repair";
import { readAgentPsdTemplates } from "@/lib/agents/psd-template-settings";

export const runtime = "nodejs";
export const dynamic = "force-dynamic";

function jsonError(status: number, error: string) {
  const payload: AgentPsdTemplateMutationResponse = {
    success: false,
    error,
  };
  return NextResponse.json(payload, { status });
}

export async function GET(
  _request: Request,
  context: { params: Promise<{ id: string }> }
) {
  const session = await auth().catch(() => null);
  if (!session?.user?.id) {
    return jsonError(401, "未登录");
  }

  try {
    const { id } = await context.params;
    const [templates, fonts] = await Promise.all([
      readAgentPsdTemplates(),
      readAgentPsdFonts().catch(
        () => [] as Awaited<ReturnType<typeof readAgentPsdFonts>>
      ),
    ]);
    const fontMap = new Map(fonts.map((font) => [font.id, font]));
    const currentTemplate = templates.find(
      (candidateTemplate) => candidateTemplate.id === id
    );

    if (!currentTemplate || currentTemplate.status !== "active") {
      return jsonError(404, "未找到 PSD 模板");
    }

    const repairedTemplate = await repairAgentPsdTemplateAssetsIfNeeded(
      currentTemplate
    );
    if (repairedTemplate !== currentTemplate) {
      await upsertSystemSetting({
        key: AGENT_PSD_TEMPLATES_KEY,
        value: templates.map((entry) =>
          entry.id === currentTemplate.id ? repairedTemplate : entry
        ),
        updatedBy: session.user.id,
      }).catch((error) => {
        console.warn("[PSD Templates] failed to persist repaired detail assets:", {
          templateId: currentTemplate.id,
          error,
        });
      });
    }

    if (!isAgentPsdTemplateReady(repairedTemplate)) {
      return jsonError(409, "PSD 模板尚未完成解析");
    }

    if (!isAgentPsdTemplateRuntimeReady(repairedTemplate)) {
      return jsonError(409, "PSD 模板资源尚未准备完成，请稍后重试");
    }

    if (getEditableAgentPsdTemplateLayers(repairedTemplate).length === 0) {
      return jsonError(409, "当前模板没有可编辑图层");
    }

    const template = repairAgentPsdTemplateFontBindings(repairedTemplate, fonts);
    const normalizedTemplate = {
      ...template,
      layers: template.layers.map((layer) => {
        if (!isAgentPsdTextLayerSlot(layer) || !layer.fontId) {
          return layer;
        }

        const font = fontMap.get(layer.fontId);
        if (!font) {
          return layer;
        }

        return {
          ...layer,
          fontFileUrl: font.fileUrl,
          fontContentType: font.contentType,
        };
      }),
    };

    const response = NextResponse.json({
      success: true,
      template: normalizedTemplate,
    } satisfies AgentPsdTemplateMutationResponse);
    response.headers.set(
      "Cache-Control",
      "private, max-age=60, stale-while-revalidate=300"
    );
    return response;
  } catch (error) {
    console.error("[PSD Templates] detail failed:", error);
    return jsonError(503, "PSD 模板详情读取失败");
  }
}