import type { ImageMetadata, ViteUserConfig } from "astro";

import type { StarlightPluginsDocsComponentsConfig } from "..";

export function vitePluginStarlightPluginsDocsComponentsConfig(
  config: StarlightPluginsDocsComponentsConfig
): VitePlugin {
  const modules = {
    "virtual:starlight-plugins-docs-components-context": `export default {
            githubOwner: ${JSON.stringify(config.githubOwner)},
            pluginName: ${JSON.stringify(config.pluginName)},
            showcaseFilepath: ${JSON.stringify(config.showcaseFilepath)},
            showcaseProps: {
                entries: [
                    ${config.showcaseProps.entries
                      .map(
                        (entry) => `{
                                thumbnail: await import(${JSON.stringify(
                                  entry.thumbnail
                                )}),
                                href: ${JSON.stringify(entry.href)},
                                title: ${JSON.stringify(entry.title)},
                                description: ${JSON.stringify(
                                  entry.description
                                )}
                            }`
                      )
                      .join(",")}
                ]
            }
        }`,
  };

  const moduleResolutionMap = Object.fromEntries(
    (Object.keys(modules) as (keyof typeof modules)[]).map((key) => [
      resolveVirtualModuleId(key),
      key,
    ])
  );

  return {
    name: "vite-plugin-starlight-plugins-docs-components",
    load(id) {
      const moduleId = moduleResolutionMap[id];
      return moduleId ? modules[moduleId] : undefined;
    },
    resolveId(id) {
      return id in modules ? resolveVirtualModuleId(id) : undefined;
    },
  };
}

function resolveVirtualModuleId<TModuleId extends string>(
  id: TModuleId
): `\0${TModuleId}` {
  return `\0${id}`;
}

export interface StarlightPluginsDocsComponentsContext {
  githubOwner: string;
  pluginName: string;
  showcaseFilepath: string;
  showcaseProps: {
    entries: {
      thumbnail: Promise<{
        default: ImageMetadata;
      }>;
      href: string;
      title: string;
      description?: string;
    }[];
  };
}

type VitePlugin = NonNullable<ViteUserConfig["plugins"]>[number];