import * as path from "path";
import { schemaToTypeString } from "../index.js";
import type { PropertyConfig } from "./types.js";

/**
 * Generate TypeScript interface for the CSV data
 */
export function generateTypeDefinition(
  resourceName: string,
  propertyConfigs: PropertyConfig[],
  references: Set<string>,
  currentFilePath?: string,
): string {
  const typeName = resourceName ? `${resourceName}Table` : "Table";
  const currentTableName = currentFilePath
    ? path.basename(currentFilePath, path.extname(currentFilePath))
    : undefined;
  const singularType = resourceName
    ? resourceName.charAt(0).toUpperCase() + resourceName.slice(1)
    : `${typeName}[number]`;

  // Generate import statements for referenced tables
  const imports: string[] = [];
  const resourceNames = new Map<string, string>();

  references.forEach((tableName) => {
    if (tableName === currentTableName) {
      resourceNames.set(tableName, singularType);
      return;
    }
    // Convert table name to type name by capitalizing
    const typeBase = tableName.charAt(0).toUpperCase() + tableName.slice(1);
    resourceNames.set(tableName, typeBase);

    // Generate import path based on current file path
    let importPath: string;
    if (currentFilePath) {
      importPath = `./${tableName}.csv`;
    } else {
      importPath = `../${tableName}.csv`;
    }
    imports.push(`import type { ${typeBase} } from '${importPath}';`);
  });

  const importSection = imports.length > 0 ? imports.join("\n") + "\n\n" : "";

  const properties = propertyConfigs
    .map(
      (config) =>
        `    readonly ${config.name}: ${schemaToTypeString(config.schema, resourceNames)};`,
    )
    .join("\n");

  let exportAlias = "";
  if (resourceName) {
    const singularType =
      resourceName.charAt(0).toUpperCase() + resourceName.slice(1);
    exportAlias = `\nexport type ${singularType} = ${typeName}[number];`;
  }

  return `${importSection}type ${typeName} = readonly {
${properties}
}[];
${exportAlias}

declare function getData(): ${typeName};
export default getData;
`;
}