import { readFile, writeFile } from 'node:fs/promises';
import MagicString from 'magic-string';
import * as svelteCompiler from 'svelte/compiler'; // Works for Svelte 3/4/5
import { type Node, Project, type SourceFile } from 'ts-morph';
type TsReplacement = {
node: Node;
key: string;
type: 'jsx-text' | 'jsx-attribute' | 'string-literal';
};
type Tools = {
generateKey: (text: string, existingKeys: Set<string>) => string;
shouldExtract: (text: string) => boolean;
extractTsContent: (
sourceFile: SourceFile,
existingKeys: Set<string>
) => {
extractedContent: Record<string, string>;
replacements: TsReplacement[];
};
};
const ATTRIBUTES_TO_EXTRACT = [
'title',
'placeholder',
'alt',
'aria-label',
'label',
];
export const processSvelteFile = async (
filePath: string,
componentKey: string,
packageName: string,
tools: Tools,
save: boolean = true
) => {
const { generateKey, shouldExtract, extractTsContent } = tools;
const code = await readFile(filePath, 'utf-8');
const ast = svelteCompiler.parse(code);
const magic = new MagicString(code);
const extractedContent: Record<string, string> = {};
const existingKeys = new Set<string>();
const walkSvelte = (node: any) => {
if (node.type === 'Text') {
const text = node.data;
if (shouldExtract(text)) {
const key = generateKey(text, existingKeys);
existingKeys.add(key);
extractedContent[key] = text.replace(/\s+/g, ' ').trim();
magic.overwrite(node.start, node.end, `{$content.${key}}`);
}
} else if (
node.type === 'Attribute' &&
ATTRIBUTES_TO_EXTRACT.includes(node.name)
) {
if (
node.value &&
node.value.length === 1 &&
node.value[0].type === 'Text'
) {
const text = node.value[0].data;
if (shouldExtract(text)) {
const key = generateKey(text, existingKeys);
existingKeys.add(key);
extractedContent[key] = text.trim();
magic.overwrite(
node.start,
node.end,
`${node.name}={$content.${key}}`
);
}
}
}
if (node.children) node.children.forEach(walkSvelte);
else if (node.fragment?.children)
node.fragment.children.forEach(walkSvelte);
if (node.attributes) node.attributes.forEach(walkSvelte);
};
walkSvelte(ast.html);
const scriptRegex = /<script[^>]*>([\s\S]*?)<\/script>/;
const match = scriptRegex.exec(code);
let scriptExtractedKeys = 0;
if (match) {
const scriptContent = match[1];
// Offset: index + length of opening tag. match[0] is whole tag, match[1] is content.
// match.index is start of <script...
const openTagLength = match[0].indexOf(scriptContent);
const scriptOffset = match.index + openTagLength;
const project = new Project({ skipAddingFilesFromTsConfig: true });
const sourceFile = project.createSourceFile('temp.ts', scriptContent);
const { extractedContent: scriptExtracted, replacements } =
extractTsContent(sourceFile, existingKeys);
Object.assign(extractedContent, scriptExtracted);
scriptExtractedKeys = Object.keys(scriptExtracted).length;
for (const { node, key } of replacements) {
const start = scriptOffset + node.getStart();
const end = scriptOffset + node.getEnd();
magic.overwrite(start, end, `get(content).${key}`);
}
}
if (Object.keys(extractedContent).length === 0) return null;
// Inject Script
const importStmt = `import { useIntlayer } from '${packageName}';`;
const getImportStmt = `import { get } from 'svelte/store';`;
const callStmt = `const content = useIntlayer('${componentKey}');`;
if (match) {
const scriptContentStart = match.index + match[0].indexOf('>') + 1;
magic.appendLeft(
scriptContentStart,
`\n ${importStmt}\n ${scriptExtractedKeys > 0 ? getImportStmt : ''}\n ${callStmt}\n`
);
} else {
magic.prepend(`<script>\n ${importStmt}\n ${callStmt}\n</script>\n`);
}
if (save) {
await writeFile(filePath, magic.toString());
}
return extractedContent;
};
