import {existsSync, readFileSync, writeFileSync} from 'fs';
import path from 'path';
import {StudioServerInternals} from '@remotion/studio-server';

const ROOT_RELATIVE_PATH = path.join('remotion', 'Root.tsx');
const TEMPLATE_COMPOSITION_ID = 'empty';

const compositionExists = (src: string, compositionId: string) => {
	return (
		src.includes(`id="${compositionId}"`) ||
		src.includes(`id={'${compositionId}'}`) ||
		src.includes(`id={"${compositionId}"}`)
	);
};

const getDefaultPropsForNewProject = () => ({
	theme: 'light',
	canvasLayout: 'square',
	platform: 'youtube',
	scenes: [
		{
			type: 'videoscene',
			webcamPosition: 'bottom-right',
			endOffset: 0,
			transitionToNextScene: false,
			newChapter: '',
			stopChapteringAfterThis: false,
			music: 'none',
			startOffset: 0,
			bRolls: [],
		},
	],
	scenesAndMetadata: [],
});

export const registerComposition = async ({
	rootDir,
	projectName,
}: {
	rootDir: string;
	projectName: string;
}): Promise<{registered: boolean; reason?: string}> => {
	const rootPath = path.join(rootDir, ROOT_RELATIVE_PATH);

	if (!existsSync(rootPath)) {
		return {registered: false, reason: 'Root.tsx not found'};
	}

	const src = readFileSync(rootPath, 'utf-8');

	if (compositionExists(src, projectName)) {
		return {registered: false, reason: 'Composition already exists'};
	}

	try {
		const duplicated = await StudioServerInternals.applyCodemodToFile({
			filePath: rootPath,
			codeMod: {
				type: 'duplicate-composition',
				idToDuplicate: TEMPLATE_COMPOSITION_ID,
				newId: projectName,
				newHeight: null,
				newWidth: null,
				newFps: null,
				newDurationInFrames: null,
				tag: 'Composition',
			},
		});

		const {output: withDefaultScene} =
			await StudioServerInternals.updateDefaultProps({
				input: duplicated,
				compositionId: projectName,
				newDefaultProps: getDefaultPropsForNewProject(),
				enumPaths: [],
			});

		const formatted = await StudioServerInternals.formatOutput(
			withDefaultScene,
		);

		writeFileSync(rootPath, formatted, 'utf-8');
		return {registered: true};
	} catch (err) {
		return {
			registered: false,
			reason: err instanceof Error ? err.message : String(err),
		};
	}
};