import type { Plugin, PluginOption } from "vite";
import { svelte } from "@sveltejs/vite-plugin-svelte";
import { join, dirname } from "path";
import { createRequire } from "module";
import { readFileSync } from "fs";
import { type ComponentConfig } from "./dev";
import type { PreprocessorGroup } from "svelte/compiler";
import { sveltePreprocess } from "svelte-preprocess";

const svelte_codes_to_ignore: Record<string, string> = {
	"reactive-component": "Icon"
};

export function plugins(config: ComponentConfig): PluginOption[] {
	const _additional_plugins = config.plugins || [];
	const _additional_svelte_preprocess = config.svelte?.preprocess || [];
	const _svelte_extensions = (config.svelte?.extensions || [".svelte"]).map(
		(ext) => {
			if (ext.trim().startsWith(".")) {
				return ext;
			}
			return `.${ext.trim()}`;
		}
	);

	if (!_svelte_extensions.includes(".svelte")) {
		_svelte_extensions.push(".svelte");
	}

	return [
		svelte({
			inspector: false,
			onwarn(warning, handler) {
				if (
					svelte_codes_to_ignore.hasOwnProperty(warning.code) &&
					svelte_codes_to_ignore[warning.code] &&
					warning.message.includes(svelte_codes_to_ignore[warning.code])
				) {
					return;
				}
				handler!(warning);
			},
			prebundleSvelteLibraries: false,
			compilerOptions: {
				discloseVersion: false,
				hmr: true
			},
			extensions: _svelte_extensions,
			preprocess: [
				sveltePreprocess({
					typescript: {
						compilerOptions: {
							declaration: false,
							declarationMap: false
						}
					}
				}),
				...(_additional_svelte_preprocess as PreprocessorGroup[])
			]
		}),
		..._additional_plugins
	];
}

function resolve_svelte_entry(id: string, base_dir: string): string | null {
	const require_fn = createRequire(join(base_dir, "frontend", "_"));
	try {
		const svelte_pkg_path = require_fn.resolve("svelte/package.json");
		const svelte_dir = dirname(svelte_pkg_path);
		const pkg = JSON.parse(readFileSync(svelte_pkg_path, "utf-8"));

		const subpath = id === "svelte" ? "." : "./" + id.slice("svelte/".length);

		if (pkg.exports && pkg.exports[subpath]) {
			const entry = pkg.exports[subpath];
			const resolved =
				typeof entry === "string" ? entry : entry.browser || entry.default;
			if (resolved) {
				return join(svelte_dir, resolved);
			}
		}
	} catch {
		return null;
	}
	return null;
}

interface GradioPluginOptions {
	svelte_dir: string;
	component_dir: string;
	backend_port?: number;
	imports?: string;
	runtimes?: string;
}

export function make_gradio_plugin({
	backend_port,
	component_dir,
	imports,
	runtimes
}: GradioPluginOptions): Plugin {
	const v_id = "virtual:component-loader";
	const v_id_2 = "virtual:cc-init";
	const resolved_v_id = "\0" + v_id;
	const resolved_v_id_2 = "\0" + v_id_2;
	return {
		name: "gradio",
		enforce: "pre",
		resolveId(id) {
			if (id === v_id) {
				return resolved_v_id;
			}
			if (id === v_id_2) {
				return resolved_v_id_2;
			}

			if (id.startsWith("svelte")) {
				const resolved = resolve_svelte_entry(id, component_dir);
				if (resolved) {
					return resolved;
				}
			}
		},
		load(id) {
			if (id === resolved_v_id) {
				return `export default {};`;
			}

			if (id === resolved_v_id_2) {
				return `window.__GRADIO_DEV__ = "dev";
      window.__GRADIO__SERVER_PORT__ = ${backend_port};
      window.__GRADIO__CC__ = ${imports};
      window.__GRADIO__CC__RUNTIMES__ = ${runtimes};`;
			}
		},
		transform(code, id) {
			return code.replace('"_NORMAL_"', '"_CC_"');
		}
	};
}

// export const deepmerge_plugin: Plugin = {
//   name: "deepmerge",
//   enforce: "pre",
//   resolveId(id) {
//     if (id === "deepmerge") {
//       return "deepmerge_internal";
//     }
//   },
//   load(id) {
//     if (id === "deepmerge_internal") {
//       return deepmerge;
//     }
//   },
// };