import { TEXT_TO_FELT_MAX_LEN } from '../strk-types/constants.js'
import { addHexPrefix, removeHexPrefix } from './encode.js'
import { isHex, isStringWholeNumber } from './num.js'
import { isString } from './typed.js'

/**
 * Test if string contains only ASCII characters (string can be ascii text)
 * @param {string} str The string to test
 * @returns {boolean} Returns true if the string contains only ASCII characters, otherwise false
 * @example
 * ```typescript
 * const result = shortString.isASCII("Hello, world!");
 * // result = true
 * const result = shortString.isASCII("Hello, 世界!");
 * // result = false
 * ```
 */
export function isASCII(str: string): boolean {
  // eslint-disable-next-line no-control-regex
  // biome-ignore lint/suspicious/noControlCharactersInRegex: <explanation>
  return /^[\x00-\x7F]*$/.test(str)
}

/**
 * Test if a string is a Cairo short string (string with less or equal 31 characters)
 * @param {string} str the string to test
 * @returns {boolean} Returns true if the string has less than or equal to 31 characters, otherwise false.
 * @example
 * ```typescript
 * const result = shortString.isShortString("Hello, world!");
 * // result = true
 * ```
 */
export function isShortString(str: string): boolean {
  return str.length <= TEXT_TO_FELT_MAX_LEN
}

/**
 * Test if string contains only numbers (string can be converted to decimal integer number)
 * @param {string} str the string to test.
 * @returns {boolean} Returns true if the string contains only numbers, otherwise false.
 * @example
 * ```typescript
 * const result = shortString.isDecimalString("12345");
 * // result = true
 * const result = shortString.isDecimalString("12a45");
 * // result = false
 * ```
 */
export function isDecimalString(str: string): boolean {
  return /^[0-9]*$/i.test(str)
}

/**
 * Test if value is a pure string text, and not a hex string or number string
 * @param {any} val the value to test
 * @returns {boolean} returns true if the value is a free-form string text, otherwise false
 * @example
 * ```typescript
 * const result = shortString.isText("Hello, world!");
 * // result = true
 * const result = shortString.isText("0x7aec92f706");
 * // result = false
 * ```
 */
export function isText(val: any): boolean {
  return isString(val) && !isHex(val) && !isStringWholeNumber(val)
}

/**
 * Test if value is short text
 * @param {any} val - The item to test
 * @returns {boolean} Returns true if the value is a short text (string has less or equal 31 characters), otherwise false
 * @example
 * ```typescript
 * const result = shortString.isShortText("Hello, world!");
 * // result = true
 * ```
 */
export const isShortText = (val: any): boolean =>
  isText(val) && isShortString(val)

/**
 * Test if value is long text
 * @param {any} val the value to test
 * @returns {boolean} returns true if the value is a long text(string has more than 31 characters), otherwise false.
 * @example
 * ```typescript
 * const result = shortString.isLongText("Hello, world! this is some random long string to enable you test isLongText function.");
 * // result = true
 * ```
 */
export const isLongText = (val: any): boolean =>
  isText(val) && !isShortString(val)

/**
 * Split long text (string greater than 31 characters) into short strings (string lesser or equal 31 characters)
 * @param {string} longStr the long text (string greater than 31 characters) to split
 * @returns {string[]} an array of short strings (string lesser or equal 31 characters).
 * @example
 * ```typescript
 * const result = shortString.splitLongString("Hello, world! we just testing splitLongString function.");
 * // result = [ 'Hello, world! we just testing s', 'plitLongString function.' ]
 * ```
 */
export function splitLongString(longStr: string): string[] {
  const regex = RegExp(`[^]{1,${TEXT_TO_FELT_MAX_LEN}}`, 'g')
  return longStr.match(regex) || []
}

/**
 * Convert an ASCII short string to a hexadecimal string.
 * @param {string} str short string (ASCII string, 31 characters max)
 * @returns {string} hex-string with 248 bits max
 * @example
 * ```typescript
 * const result = shortString.encodeShortString("uri/pict/t38.jpg");
 * // result = "0x7572692f706963742f7433382e6a7067"
 * ```
 */
export function encodeShortString(str: string): string {
  if (!isASCII(str)) throw new Error(`${str} is not an ASCII string`)
  if (!isShortString(str)) throw new Error(`${str} is too long`)
  return addHexPrefix(
    str.replace(/./g, (char) => char.charCodeAt(0).toString(16)),
  )
}

/**
 * Convert a hexadecimal or decimal string to an ASCII string.
 * @param {string} str representing a 248 bit max number (ex. "0x1A4F64EA56" or "236942575435676423")
 * @returns {string} short string; 31 characters max
 * @example
 * ```typescript
 * const result = shortString.decodeShortString("0x7572692f706963742f7433382e6a7067");
 * // result = "uri/pict/t38.jpg"
 * ```
 */
export function decodeShortString(str: string): string {
  if (!isASCII(str)) throw new Error(`${str} is not an ASCII string`)
  if (isHex(str)) {
    return removeHexPrefix(str).replace(/.{2}/g, (hex) =>
      String.fromCharCode(Number.parseInt(hex, 16)),
    )
  }
  if (isDecimalString(str)) {
    return decodeShortString('0X'.concat(BigInt(str).toString(16)))
  }
  throw new Error(`${str} is not Hex or decimal`)
}