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import type {  CamelCase,  KebabCase,  PascalCase,  ScreamingSnakeCase,  SnakeCase,  StringCase,  λ,} from "./types.ts";
/** Upper-case first letter of string. */export const capitalize = <T extends string>(str: T) =>  (str[0].toUpperCase() + str.slice(1)) as Capitalize<T>;
/** Lower-case first letter of string */export const uncapitalize = <T extends string>(str: T) =>  (str[0].toLowerCase() + str.slice(1)) as Uncapitalize<T>;
/** Strictly typed `String.toUpperCase()`. */export const upper = <T extends string>(str: T) =>  str.toUpperCase() as Uppercase<T>;
/** Strictly typed `String.toLowerCase()`. */export const lower = <T extends string>(str: T) =>  str.toLowerCase() as Lowercase<T>;
/** * Transforms a variable name to snake case. * * Note: The rules for transforming anything to snake case are somewhat vague. * So use this only for very simple names where the resulting value is * absolutely unambiguous. For more examples of how names are transformed, have * a look at the test cases. * * @example * ``` * snake('fooBar') // 'foo_bar' * ``` */export const snake = <T extends string>(str: T): SnakeCase<T> =>  str    .replace(/(\p{L})-(?=\p{L})/gu, "$1_")    .replace(/(^|_)(\p{Lu})(?!\p{Lu})/gu, (_, a, b) => `${a}${b.toLowerCase()}`)    .replace(/([^\p{Lu}])(\p{Lu})(?=\p{Lu})/gu, (_, a, b) => `${a}_${b}`)    .replace(      /([^\p{Lu}_0-9])(\p{Lu})/gu,      (_, a, b) => `${a}_${b.toLowerCase()}`,    )    .replace(/(\p{Lu}[^\p{L}_]*)(\p{Ll})/gu, (_, a, b) => `${a}_${b}`) as any;
/** * Transforms a variable name to kebab case. * * Note: The rules for transforming anything to kebab case are somewhat vague. * So use this only for very simple names where the resulting value is * absolutely unambiguous. For more examples of how names are transformed, have * a look at the test cases. * * @example * ``` * kebab('fooBar') // 'foo-bar' * ``` */export const kebab = <T extends string>(str: T): KebabCase<T> =>  str    .replace(/(\p{L})_(?=\p{L})/gu, "$1-")    .replace(/(^|-)(\p{Lu})(?!\p{Lu})/gu, (_, a, b) => `${a}${b.toLowerCase()}`)    .replace(/([^\p{Lu}])(\p{Lu})(?=\p{Lu})/gu, (_, a, b) => `${a}-${b}`)    .replace(      /([^\p{Lu}\-0-9])(\p{Lu})/gu,      (_, a, b) => `${a}-${b.toLowerCase()}`,    )    .replace(/(\p{Lu}[^\p{L}\-]*)(\p{Ll})/gu, (_, a, b) => `${a}-${b}`) as any;
/** * Transforms a variable name to camel case. * * Note: The rules for transforming anything to camel case are somewhat vague. * So use this only for very simple names where the resulting value is * absolutely unambiguous. For more examples of how names are transformed, have * a look at the test cases. * * @example * ``` * camel('foo_bar') // 'fooBar' * ``` */export const camel = <T extends string>(str: T): CamelCase<T> =>  str    .replace(/^\p{Lu}/u, (v) => v.toLowerCase())    .replace(      /([^_-][_-]*)[_-](\p{L})/gu,      (_, a, b) => a + b.toUpperCase(),    ) as any;
/** * Transforms a variable name to pascal case. * * Note: The rules for transforming anything to pascal case are somewhat vague. * So use this only for very simple names where the resulting value is * absolutely unambiguous. For more examples of how names are transformed, have * a look at the test cases. * * @example * ``` * pascal('foo_bar') // 'FooBar' * ``` */export const pascal = <T extends string>(str: T): PascalCase<T> =>  capitalize(camel(str));
/** * Transforms a variable name to screaming snake case. * * @see {@link snake} * * @example * ``` * screamingSnake('fooBar') // 'FOO_BAR' * ``` */export const screamingSnake = <T extends string>(  str: T,): ScreamingSnakeCase<T> => upper(snake(str));
/** * Transform a variable name to `targetCase` * * @see {@link snake} * @see {@link kebab} * @see {@link camel} * @see {@link pascal} * @see {@link screamingSnake} */export const transformCase = <T extends string, C extends StringCase>(  str: T,  targetCase: C,): C extends "snake" ? SnakeCase<T> : never => {  if (!(targetCase in converters)) {    throw Error(`can't convert to ${targetCase} case`);  }  return converters[targetCase](str) as any;};
const converters: Record<StringCase, λ<[string], string>> = {  camel,  kebab,  pascal,  snake,  "screaming-snake": screamingSnake,};