import path from 'path';
import { Plugin, UserConfig, HtmlTagDescriptor } from 'vite';
import fs from 'fs-extra';
import externalGlobals from 'rollup-plugin-external-globals';
import serveStatic from 'serve-static';

interface VitePluginCesiumOptions {
  rebuildCesium?: boolean;
  minifyCesium?: boolean;
}

function vitePluginCesium(
  options: VitePluginCesiumOptions = {
    rebuildCesium: false,
    minifyCesium: false
  }
): Plugin {
  const { rebuildCesium, minifyCesium } = options;

  const cesiumBuildRootPath = 'node_modules/cesium/Build';
  const cesiumBuildPath = 'node_modules/cesium/Build/Cesium/';
  const CESIUM_BASE_URL = '/cesium/';

  let publicPath = 'public';
  let outDir = 'dist';
  let base: string;
  let isBuild: boolean = false;

  return {
    name: 'vite-plugin-cesium',

    config(_, { command }) {
      const userConfig: UserConfig = {
        build: {
          assetsInlineLimit: 0,
          chunkSizeWarningLimit: 4000
        },
        define: {
          CESIUM_BASE_URL
        }
      };
      if (command === 'build' && !rebuildCesium) {
        userConfig.build!.rollupOptions = {
          external: ['cesium'],
          plugins: [externalGlobals({ cesium: 'Cesium' })]
        };
      }

      return userConfig;
    },

    configResolved(resolvedConfig) {
      publicPath = resolvedConfig.publicDir;
      outDir = resolvedConfig.build.outDir;
      base = resolvedConfig.base;
      isBuild =
        resolvedConfig.isProduction || resolvedConfig.command === 'build';
    },

    configureServer({ middlewares }) {
      const cesiumPath = path.join(
        cesiumBuildRootPath,
        minifyCesium ? 'Cesium' : 'CesiumUnminified'
      );
      middlewares.use(CESIUM_BASE_URL, serveStatic(cesiumPath));
    },

    async buildStart() {
      if (isBuild) {
        const exists = await fs.pathExists(path.join(publicPath, 'cesium'));

        if (!exists) {
          try {
            await fs.copy(
              path.join(cesiumBuildPath, 'Assets'),
              path.join(publicPath, 'cesium/Assets')
            );
            await fs.copy(
              path.join(cesiumBuildPath, 'ThirdParty'),
              path.join(publicPath, 'cesium/ThirdParty')
            );
            await fs.copy(
              path.join(cesiumBuildPath, 'Workers'),
              path.join(publicPath, 'cesium/Workers')
            );
            await fs.copy(
              path.join(cesiumBuildPath, 'Widgets'),
              path.join(publicPath, 'cesium/Widgets')
            );
          } catch (err) {
            console.error('copy failed', err);
          }
        }
        if (rebuildCesium) {
          await fs.remove(path.join(publicPath, 'cesium/Cesium.js'));
        } else {
          await fs.copy(
            path.join(cesiumBuildPath, 'Cesium.js'),
            path.join(publicPath, 'cesium/Cesium.js')
          );
        }
      }
    },
    async renderStart() {
      const existOutDir = await fs.pathExists(path.join(outDir, 'cesium'));
      if (existOutDir) {
        await fs.remove(path.join(publicPath, 'cesium'));
      }
    },

    transformIndexHtml() {
      const tags: HtmlTagDescriptor[] = [
        {
          tag: 'link',
          attrs: {
            rel: 'stylesheet',
            href: base + 'cesium/Widgets/widgets.css'
          }
        }
      ];
      if (!rebuildCesium) {
        tags.push({ tag: 'script', attrs: { src: base + 'cesium/Cesium.js' } });
      }
      return tags;
    }
  };
}

export default vitePluginCesium;