import { c as createCommonjsModule } from './_commonjsHelpers.js';

/**
 * Memize options object.
 *
 * @typedef MemizeOptions
 *
 * @property {number} [maxSize] Maximum size of the cache.
 */

/**
 * Internal cache entry.
 *
 * @typedef MemizeCacheNode
 *
 * @property {?MemizeCacheNode|undefined} [prev] Previous node.
 * @property {?MemizeCacheNode|undefined} [next] Next node.
 * @property {Array<*>}                   args   Function arguments for cache
 *                                               entry.
 * @property {*}                          val    Function result.
 */

/**
 * Properties of the enhanced function for controlling cache.
 *
 * @typedef MemizeMemoizedFunction
 *
 * @property {()=>void} clear Clear the cache.
 */

/**
 * Accepts a function to be memoized, and returns a new memoized function, with
 * optional options.
 *
 * @template {Function} F
 *
 * @param {F}             fn        Function to memoize.
 * @param {MemizeOptions} [options] Options object.
 *
 * @return {F & MemizeMemoizedFunction} Memoized function.
 */
function memize( fn, options ) {
	var size = 0;

	/** @type {?MemizeCacheNode|undefined} */
	var head;

	/** @type {?MemizeCacheNode|undefined} */
	var tail;

	options = options || {};

	function memoized( /* ...args */ ) {
		var node = head,
			len = arguments.length,
			args, i;

		searchCache: while ( node ) {
			// Perform a shallow equality test to confirm that whether the node
			// under test is a candidate for the arguments passed. Two arrays
			// are shallowly equal if their length matches and each entry is
			// strictly equal between the two sets. Avoid abstracting to a
			// function which could incur an arguments leaking deoptimization.

			// Check whether node arguments match arguments length
			if ( node.args.length !== arguments.length ) {
				node = node.next;
				continue;
			}

			// Check whether node arguments match arguments values
			for ( i = 0; i < len; i++ ) {
				if ( node.args[ i ] !== arguments[ i ] ) {
					node = node.next;
					continue searchCache;
				}
			}

			// At this point we can assume we've found a match

			// Surface matched node to head if not already
			if ( node !== head ) {
				// As tail, shift to previous. Must only shift if not also
				// head, since if both head and tail, there is no previous.
				if ( node === tail ) {
					tail = node.prev;
				}

				// Adjust siblings to point to each other. If node was tail,
				// this also handles new tail's empty `next` assignment.
				/** @type {MemizeCacheNode} */ ( node.prev ).next = node.next;
				if ( node.next ) {
					node.next.prev = node.prev;
				}

				node.next = head;
				node.prev = null;
				/** @type {MemizeCacheNode} */ ( head ).prev = node;
				head = node;
			}

			// Return immediately
			return node.val;
		}

		// No cached value found. Continue to insertion phase:

		// Create a copy of arguments (avoid leaking deoptimization)
		args = new Array( len );
		for ( i = 0; i < len; i++ ) {
			args[ i ] = arguments[ i ];
		}

		node = {
			args: args,

			// Generate the result from original function
			val: fn.apply( null, args ),
		};

		// Don't need to check whether node is already head, since it would
		// have been returned above already if it was

		// Shift existing head down list
		if ( head ) {
			head.prev = node;
			node.next = head;
		} else {
			// If no head, follows that there's no tail (at initial or reset)
			tail = node;
		}

		// Trim tail if we're reached max size and are pending cache insertion
		if ( size === /** @type {MemizeOptions} */ ( options ).maxSize ) {
			tail = /** @type {MemizeCacheNode} */ ( tail ).prev;
			/** @type {MemizeCacheNode} */ ( tail ).next = null;
		} else {
			size++;
		}

		head = node;

		return node.val;
	}

	memoized.clear = function() {
		head = null;
		tail = null;
		size = 0;
	};

	// Ignore reason: There's not a clear solution to create an intersection of
	// the function with additional properties, where the goal is to retain the
	// function signature of the incoming argument and add control properties
	// on the return value.

	// @ts-ignore
	return memoized;
}

var memize_1 = memize;

var sprintf = createCommonjsModule(function (module, exports) {
/* global window, exports, define */

!function() {

    var re = {
        not_string: /[^s]/,
        not_bool: /[^t]/,
        not_type: /[^T]/,
        not_primitive: /[^v]/,
        number: /[diefg]/,
        numeric_arg: /[bcdiefguxX]/,
        json: /[j]/,
        not_json: /[^j]/,
        text: /^[^\x25]+/,
        modulo: /^\x25{2}/,
        placeholder: /^\x25(?:([1-9]\d*)\$|\(([^)]+)\))?(\+)?(0|'[^$])?(-)?(\d+)?(?:\.(\d+))?([b-gijostTuvxX])/,
        key: /^([a-z_][a-z_\d]*)/i,
        key_access: /^\.([a-z_][a-z_\d]*)/i,
        index_access: /^\[(\d+)\]/,
        sign: /^[+-]/
    };

    function sprintf(key) {
        // `arguments` is not an array, but should be fine for this call
        return sprintf_format(sprintf_parse(key), arguments)
    }

    function vsprintf(fmt, argv) {
        return sprintf.apply(null, [fmt].concat(argv || []))
    }

    function sprintf_format(parse_tree, argv) {
        var cursor = 1, tree_length = parse_tree.length, arg, output = '', i, k, ph, pad, pad_character, pad_length, is_positive, sign;
        for (i = 0; i < tree_length; i++) {
            if (typeof parse_tree[i] === 'string') {
                output += parse_tree[i];
            }
            else if (typeof parse_tree[i] === 'object') {
                ph = parse_tree[i]; // convenience purposes only
                if (ph.keys) { // keyword argument
                    arg = argv[cursor];
                    for (k = 0; k < ph.keys.length; k++) {
                        if (arg == undefined) {
                            throw new Error(sprintf('[sprintf] Cannot access property "%s" of undefined value "%s"', ph.keys[k], ph.keys[k-1]))
                        }
                        arg = arg[ph.keys[k]];
                    }
                }
                else if (ph.param_no) { // positional argument (explicit)
                    arg = argv[ph.param_no];
                }
                else { // positional argument (implicit)
                    arg = argv[cursor++];
                }

                if (re.not_type.test(ph.type) && re.not_primitive.test(ph.type) && arg instanceof Function) {
                    arg = arg();
                }

                if (re.numeric_arg.test(ph.type) && (typeof arg !== 'number' && isNaN(arg))) {
                    throw new TypeError(sprintf('[sprintf] expecting number but found %T', arg))
                }

                if (re.number.test(ph.type)) {
                    is_positive = arg >= 0;
                }

                switch (ph.type) {
                    case 'b':
                        arg = parseInt(arg, 10).toString(2);
                        break
                    case 'c':
                        arg = String.fromCharCode(parseInt(arg, 10));
                        break
                    case 'd':
                    case 'i':
                        arg = parseInt(arg, 10);
                        break
                    case 'j':
                        arg = JSON.stringify(arg, null, ph.width ? parseInt(ph.width) : 0);
                        break
                    case 'e':
                        arg = ph.precision ? parseFloat(arg).toExponential(ph.precision) : parseFloat(arg).toExponential();
                        break
                    case 'f':
                        arg = ph.precision ? parseFloat(arg).toFixed(ph.precision) : parseFloat(arg);
                        break
                    case 'g':
                        arg = ph.precision ? String(Number(arg.toPrecision(ph.precision))) : parseFloat(arg);
                        break
                    case 'o':
                        arg = (parseInt(arg, 10) >>> 0).toString(8);
                        break
                    case 's':
                        arg = String(arg);
                        arg = (ph.precision ? arg.substring(0, ph.precision) : arg);
                        break
                    case 't':
                        arg = String(!!arg);
                        arg = (ph.precision ? arg.substring(0, ph.precision) : arg);
                        break
                    case 'T':
                        arg = Object.prototype.toString.call(arg).slice(8, -1).toLowerCase();
                        arg = (ph.precision ? arg.substring(0, ph.precision) : arg);
                        break
                    case 'u':
                        arg = parseInt(arg, 10) >>> 0;
                        break
                    case 'v':
                        arg = arg.valueOf();
                        arg = (ph.precision ? arg.substring(0, ph.precision) : arg);
                        break
                    case 'x':
                        arg = (parseInt(arg, 10) >>> 0).toString(16);
                        break
                    case 'X':
                        arg = (parseInt(arg, 10) >>> 0).toString(16).toUpperCase();
                        break
                }
                if (re.json.test(ph.type)) {
                    output += arg;
                }
                else {
                    if (re.number.test(ph.type) && (!is_positive || ph.sign)) {
                        sign = is_positive ? '+' : '-';
                        arg = arg.toString().replace(re.sign, '');
                    }
                    else {
                        sign = '';
                    }
                    pad_character = ph.pad_char ? ph.pad_char === '0' ? '0' : ph.pad_char.charAt(1) : ' ';
                    pad_length = ph.width - (sign + arg).length;
                    pad = ph.width ? (pad_length > 0 ? pad_character.repeat(pad_length) : '') : '';
                    output += ph.align ? sign + arg + pad : (pad_character === '0' ? sign + pad + arg : pad + sign + arg);
                }
            }
        }
        return output
    }

    var sprintf_cache = Object.create(null);

    function sprintf_parse(fmt) {
        if (sprintf_cache[fmt]) {
            return sprintf_cache[fmt]
        }

        var _fmt = fmt, match, parse_tree = [], arg_names = 0;
        while (_fmt) {
            if ((match = re.text.exec(_fmt)) !== null) {
                parse_tree.push(match[0]);
            }
            else if ((match = re.modulo.exec(_fmt)) !== null) {
                parse_tree.push('%');
            }
            else if ((match = re.placeholder.exec(_fmt)) !== null) {
                if (match[2]) {
                    arg_names |= 1;
                    var field_list = [], replacement_field = match[2], field_match = [];
                    if ((field_match = re.key.exec(replacement_field)) !== null) {
                        field_list.push(field_match[1]);
                        while ((replacement_field = replacement_field.substring(field_match[0].length)) !== '') {
                            if ((field_match = re.key_access.exec(replacement_field)) !== null) {
                                field_list.push(field_match[1]);
                            }
                            else if ((field_match = re.index_access.exec(replacement_field)) !== null) {
                                field_list.push(field_match[1]);
                            }
                            else {
                                throw new SyntaxError('[sprintf] failed to parse named argument key')
                            }
                        }
                    }
                    else {
                        throw new SyntaxError('[sprintf] failed to parse named argument key')
                    }
                    match[2] = field_list;
                }
                else {
                    arg_names |= 2;
                }
                if (arg_names === 3) {
                    throw new Error('[sprintf] mixing positional and named placeholders is not (yet) supported')
                }

                parse_tree.push(
                    {
                        placeholder: match[0],
                        param_no:    match[1],
                        keys:        match[2],
                        sign:        match[3],
                        pad_char:    match[4],
                        align:       match[5],
                        width:       match[6],
                        precision:   match[7],
                        type:        match[8]
                    }
                );
            }
            else {
                throw new SyntaxError('[sprintf] unexpected placeholder')
            }
            _fmt = _fmt.substring(match[0].length);
        }
        return sprintf_cache[fmt] = parse_tree
    }

    /**
     * export to either browser or node.js
     */
    /* eslint-disable quote-props */
    {
        exports['sprintf'] = sprintf;
        exports['vsprintf'] = vsprintf;
    }
    if (typeof window !== 'undefined') {
        window['sprintf'] = sprintf;
        window['vsprintf'] = vsprintf;
    }
    /* eslint-enable quote-props */
}(); // eslint-disable-line
});

var PRECEDENCE, OPENERS, TERMINATORS, PATTERN;

/**
 * Operator precedence mapping.
 *
 * @type {Object}
 */
PRECEDENCE = {
	'(': 9,
	'!': 8,
	'*': 7,
	'/': 7,
	'%': 7,
	'+': 6,
	'-': 6,
	'<': 5,
	'<=': 5,
	'>': 5,
	'>=': 5,
	'==': 4,
	'!=': 4,
	'&&': 3,
	'||': 2,
	'?': 1,
	'?:': 1,
};

/**
 * Characters which signal pair opening, to be terminated by terminators.
 *
 * @type {string[]}
 */
OPENERS = [ '(', '?' ];

/**
 * Characters which signal pair termination, the value an array with the
 * opener as its first member. The second member is an optional operator
 * replacement to push to the stack.
 *
 * @type {string[]}
 */
TERMINATORS = {
	')': [ '(' ],
	':': [ '?', '?:' ],
};

/**
 * Pattern matching operators and openers.
 *
 * @type {RegExp}
 */
PATTERN = /<=|>=|==|!=|&&|\|\||\?:|\(|!|\*|\/|%|\+|-|<|>|\?|\)|:/;

/**
 * Given a C expression, returns the equivalent postfix (Reverse Polish)
 * notation terms as an array.
 *
 * If a postfix string is desired, simply `.join( ' ' )` the result.
 *
 * @example
 *
 * ```js
 * import postfix from '@tannin/postfix';
 *
 * postfix( 'n > 1' );
 * // ⇒ [ 'n', '1', '>' ]
 * ```
 *
 * @param {string} expression C expression.
 *
 * @return {string[]} Postfix terms.
 */
function postfix( expression ) {
	var terms = [],
		stack = [],
		match, operator, term, element;

	while ( ( match = expression.match( PATTERN ) ) ) {
		operator = match[ 0 ];

		// Term is the string preceding the operator match. It may contain
		// whitespace, and may be empty (if operator is at beginning).
		term = expression.substr( 0, match.index ).trim();
		if ( term ) {
			terms.push( term );
		}

		while ( ( element = stack.pop() ) ) {
			if ( TERMINATORS[ operator ] ) {
				if ( TERMINATORS[ operator ][ 0 ] === element ) {
					// Substitution works here under assumption that because
					// the assigned operator will no longer be a terminator, it
					// will be pushed to the stack during the condition below.
					operator = TERMINATORS[ operator ][ 1 ] || operator;
					break;
				}
			} else if ( OPENERS.indexOf( element ) >= 0 || PRECEDENCE[ element ] < PRECEDENCE[ operator ] ) {
				// Push to stack if either an opener or when pop reveals an
				// element of lower precedence.
				stack.push( element );
				break;
			}

			// For each popped from stack, push to terms.
			terms.push( element );
		}

		if ( ! TERMINATORS[ operator ] ) {
			stack.push( operator );
		}

		// Slice matched fragment from expression to continue match.
		expression = expression.substr( match.index + operator.length );
	}

	// Push remainder of operand, if exists, to terms.
	expression = expression.trim();
	if ( expression ) {
		terms.push( expression );
	}

	// Pop remaining items from stack into terms.
	return terms.concat( stack.reverse() );
}

/**
 * Operator callback functions.
 *
 * @type {Object}
 */
var OPERATORS = {
	'!': function( a ) {
		return ! a;
	},
	'*': function( a, b ) {
		return a * b;
	},
	'/': function( a, b ) {
		return a / b;
	},
	'%': function( a, b ) {
		return a % b;
	},
	'+': function( a, b ) {
		return a + b;
	},
	'-': function( a, b ) {
		return a - b;
	},
	'<': function( a, b ) {
		return a < b;
	},
	'<=': function( a, b ) {
		return a <= b;
	},
	'>': function( a, b ) {
		return a > b;
	},
	'>=': function( a, b ) {
		return a >= b;
	},
	'==': function( a, b ) {
		return a === b;
	},
	'!=': function( a, b ) {
		return a !== b;
	},
	'&&': function( a, b ) {
		return a && b;
	},
	'||': function( a, b ) {
		return a || b;
	},
	'?:': function( a, b, c ) {
		if ( a ) {
			throw b;
		}

		return c;
	},
};

/**
 * Given an array of postfix terms and operand variables, returns the result of
 * the postfix evaluation.
 *
 * @example
 *
 * ```js
 * import evaluate from '@tannin/evaluate';
 *
 * // 3 + 4 * 5 / 6 ⇒ '3 4 5 * 6 / +'
 * const terms = [ '3', '4', '5', '*', '6', '/', '+' ];
 *
 * evaluate( terms, {} );
 * // ⇒ 6.333333333333334
 * ```
 *
 * @param {string[]} postfix   Postfix terms.
 * @param {Object}   variables Operand variables.
 *
 * @return {*} Result of evaluation.
 */
function evaluate( postfix, variables ) {
	var stack = [],
		i, j, args, getOperatorResult, term, value;

	for ( i = 0; i < postfix.length; i++ ) {
		term = postfix[ i ];

		getOperatorResult = OPERATORS[ term ];
		if ( getOperatorResult ) {
			// Pop from stack by number of function arguments.
			j = getOperatorResult.length;
			args = Array( j );
			while ( j-- ) {
				args[ j ] = stack.pop();
			}

			try {
				value = getOperatorResult.apply( null, args );
			} catch ( earlyReturn ) {
				return earlyReturn;
			}
		} else if ( variables.hasOwnProperty( term ) ) {
			value = variables[ term ];
		} else {
			value = +term;
		}

		stack.push( value );
	}

	return stack[ 0 ];
}

/**
 * Given a C expression, returns a function which can be called to evaluate its
 * result.
 *
 * @example
 *
 * ```js
 * import compile from '@tannin/compile';
 *
 * const evaluate = compile( 'n > 1' );
 *
 * evaluate( { n: 2 } );
 * // ⇒ true
 * ```
 *
 * @param {string} expression C expression.
 *
 * @return {(variables?:{[variable:string]:*})=>*} Compiled evaluator.
 */
function compile( expression ) {
	var terms = postfix( expression );

	return function( variables ) {
		return evaluate( terms, variables );
	};
}

/**
 * Given a C expression, returns a function which, when called with a value,
 * evaluates the result with the value assumed to be the "n" variable of the
 * expression. The result will be coerced to its numeric equivalent.
 *
 * @param {string} expression C expression.
 *
 * @return {Function} Evaluator function.
 */
function pluralForms( expression ) {
	var evaluate = compile( expression );

	return function( n ) {
		return +evaluate( { n: n } );
	};
}

/**
 * Tannin constructor options.
 *
 * @typedef {Object} TanninOptions
 *
 * @property {string}   [contextDelimiter] Joiner in string lookup with context.
 * @property {Function} [onMissingKey]     Callback to invoke when key missing.
 */

/**
 * Domain metadata.
 *
 * @typedef {Object} TanninDomainMetadata
 *
 * @property {string}            [domain]       Domain name.
 * @property {string}            [lang]         Language code.
 * @property {(string|Function)} [plural_forms] Plural forms expression or
 *                                              function evaluator.
 */

/**
 * Domain translation pair respectively representing the singular and plural
 * translation.
 *
 * @typedef {[string,string]} TanninTranslation
 */

/**
 * Locale data domain. The key is used as reference for lookup, the value an
 * array of two string entries respectively representing the singular and plural
 * translation.
 *
 * @typedef {{[key:string]:TanninDomainMetadata|TanninTranslation,'':TanninDomainMetadata|TanninTranslation}} TanninLocaleDomain
 */

/**
 * Jed-formatted locale data.
 *
 * @see http://messageformat.github.io/Jed/
 *
 * @typedef {{[domain:string]:TanninLocaleDomain}} TanninLocaleData
 */

/**
 * Default Tannin constructor options.
 *
 * @type {TanninOptions}
 */
var DEFAULT_OPTIONS = {
	contextDelimiter: '\u0004',
	onMissingKey: null,
};

/**
 * Given a specific locale data's config `plural_forms` value, returns the
 * expression.
 *
 * @example
 *
 * ```
 * getPluralExpression( 'nplurals=2; plural=(n != 1);' ) === '(n != 1)'
 * ```
 *
 * @param {string} pf Locale data plural forms.
 *
 * @return {string} Plural forms expression.
 */
function getPluralExpression( pf ) {
	var parts, i, part;

	parts = pf.split( ';' );

	for ( i = 0; i < parts.length; i++ ) {
		part = parts[ i ].trim();
		if ( part.indexOf( 'plural=' ) === 0 ) {
			return part.substr( 7 );
		}
	}
}

/**
 * Tannin constructor.
 *
 * @class
 *
 * @param {TanninLocaleData} data      Jed-formatted locale data.
 * @param {TanninOptions}    [options] Tannin options.
 */
function Tannin( data, options ) {
	var key;

	/**
	 * Jed-formatted locale data.
	 *
	 * @name Tannin#data
	 * @type {TanninLocaleData}
	 */
	this.data = data;

	/**
	 * Plural forms function cache, keyed by plural forms string.
	 *
	 * @name Tannin#pluralForms
	 * @type {Object<string,Function>}
	 */
	this.pluralForms = {};

	/**
	 * Effective options for instance, including defaults.
	 *
	 * @name Tannin#options
	 * @type {TanninOptions}
	 */
	this.options = {};

	for ( key in DEFAULT_OPTIONS ) {
		this.options[ key ] = options !== undefined && key in options
			? options[ key ]
			: DEFAULT_OPTIONS[ key ];
	}
}

/**
 * Returns the plural form index for the given domain and value.
 *
 * @param {string} domain Domain on which to calculate plural form.
 * @param {number} n      Value for which plural form is to be calculated.
 *
 * @return {number} Plural form index.
 */
Tannin.prototype.getPluralForm = function( domain, n ) {
	var getPluralForm = this.pluralForms[ domain ],
		config, plural, pf;

	if ( ! getPluralForm ) {
		config = this.data[ domain ][ '' ];

		pf = (
			config[ 'Plural-Forms' ] ||
			config[ 'plural-forms' ] ||
			// Ignore reason: As known, there's no way to document the empty
			// string property on a key to guarantee this as metadata.
			// @ts-ignore
			config.plural_forms
		);

		if ( typeof pf !== 'function' ) {
			plural = getPluralExpression(
				config[ 'Plural-Forms' ] ||
				config[ 'plural-forms' ] ||
				// Ignore reason: As known, there's no way to document the empty
				// string property on a key to guarantee this as metadata.
				// @ts-ignore
				config.plural_forms
			);

			pf = pluralForms( plural );
		}

		getPluralForm = this.pluralForms[ domain ] = pf;
	}

	return getPluralForm( n );
};

/**
 * Translate a string.
 *
 * @param {string}      domain   Translation domain.
 * @param {string|void} context  Context distinguishing terms of the same name.
 * @param {string}      singular Primary key for translation lookup.
 * @param {string=}     plural   Fallback value used for non-zero plural
 *                               form index.
 * @param {number=}     n        Value to use in calculating plural form.
 *
 * @return {string} Translated string.
 */
Tannin.prototype.dcnpgettext = function( domain, context, singular, plural, n ) {
	var index, key, entry;

	if ( n === undefined ) {
		// Default to singular.
		index = 0;
	} else {
		// Find index by evaluating plural form for value.
		index = this.getPluralForm( domain, n );
	}

	key = singular;

	// If provided, context is prepended to key with delimiter.
	if ( context ) {
		key = context + this.options.contextDelimiter + singular;
	}

	entry = this.data[ domain ][ key ];

	// Verify not only that entry exists, but that the intended index is within
	// range and non-empty.
	if ( entry && entry[ index ] ) {
		return entry[ index ];
	}

	if ( this.options.onMissingKey ) {
		this.options.onMissingKey( singular, domain );
	}

	// If entry not found, fall back to singular vs. plural with zero index
	// representing the singular value.
	return index === 0 ? singular : plural;
};

/**
 * Validate a namespace string.
 *
 * @param {string} namespace The namespace to validate - should take the form
 *                           `vendor/plugin/function`.
 *
 * @return {boolean} Whether the namespace is valid.
 */
function validateNamespace(namespace) {
  if ('string' !== typeof namespace || '' === namespace) {
    // eslint-disable-next-line no-console
    console.error('The namespace must be a non-empty string.');
    return false;
  }

  if (!/^[a-zA-Z][a-zA-Z0-9_.\-\/]*$/.test(namespace)) {
    // eslint-disable-next-line no-console
    console.error('The namespace can only contain numbers, letters, dashes, periods, underscores and slashes.');
    return false;
  }

  return true;
}

/**
 * Validate a hookName string.
 *
 * @param {string} hookName The hook name to validate. Should be a non empty string containing
 *                          only numbers, letters, dashes, periods and underscores. Also,
 *                          the hook name cannot begin with `__`.
 *
 * @return {boolean} Whether the hook name is valid.
 */
function validateHookName(hookName) {
  if ('string' !== typeof hookName || '' === hookName) {
    // eslint-disable-next-line no-console
    console.error('The hook name must be a non-empty string.');
    return false;
  }

  if (/^__/.test(hookName)) {
    // eslint-disable-next-line no-console
    console.error('The hook name cannot begin with `__`.');
    return false;
  }

  if (!/^[a-zA-Z][a-zA-Z0-9_.-]*$/.test(hookName)) {
    // eslint-disable-next-line no-console
    console.error('The hook name can only contain numbers, letters, dashes, periods and underscores.');
    return false;
  }

  return true;
}

/**
 * Internal dependencies
 */
/**
 * @callback AddHook
 *
 * Adds the hook to the appropriate hooks container.
 *
 * @param {string}               hookName      Name of hook to add
 * @param {string}               namespace     The unique namespace identifying the callback in the form `vendor/plugin/function`.
 * @param {import('.').Callback} callback      Function to call when the hook is run
 * @param {number}               [priority=10] Priority of this hook
 */

/**
 * Returns a function which, when invoked, will add a hook.
 *
 * @param {import('.').Hooks}    hooks    Hooks instance.
 * @param {import('.').StoreKey} storeKey
 *
 * @return {AddHook} Function that adds a new hook.
 */

function createAddHook(hooks, storeKey) {
  return function addHook(hookName, namespace, callback) {
    let priority = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : 10;
    const hooksStore = hooks[storeKey];

    if (!validateHookName(hookName)) {
      return;
    }

    if (!validateNamespace(namespace)) {
      return;
    }

    if ('function' !== typeof callback) {
      // eslint-disable-next-line no-console
      console.error('The hook callback must be a function.');
      return;
    } // Validate numeric priority


    if ('number' !== typeof priority) {
      // eslint-disable-next-line no-console
      console.error('If specified, the hook priority must be a number.');
      return;
    }

    const handler = {
      callback,
      priority,
      namespace
    };

    if (hooksStore[hookName]) {
      // Find the correct insert index of the new hook.
      const handlers = hooksStore[hookName].handlers;
      /** @type {number} */

      let i;

      for (i = handlers.length; i > 0; i--) {
        if (priority >= handlers[i - 1].priority) {
          break;
        }
      }

      if (i === handlers.length) {
        // If append, operate via direct assignment.
        handlers[i] = handler;
      } else {
        // Otherwise, insert before index via splice.
        handlers.splice(i, 0, handler);
      } // We may also be currently executing this hook.  If the callback
      // we're adding would come after the current callback, there's no
      // problem; otherwise we need to increase the execution index of
      // any other runs by 1 to account for the added element.


      hooksStore.__current.forEach(hookInfo => {
        if (hookInfo.name === hookName && hookInfo.currentIndex >= i) {
          hookInfo.currentIndex++;
        }
      });
    } else {
      // This is the first hook of its type.
      hooksStore[hookName] = {
        handlers: [handler],
        runs: 0
      };
    }

    if (hookName !== 'hookAdded') {
      hooks.doAction('hookAdded', hookName, namespace, callback, priority);
    }
  };
}

/**
 * Internal dependencies
 */
/**
 * @callback RemoveHook
 * Removes the specified callback (or all callbacks) from the hook with a given hookName
 * and namespace.
 *
 * @param {string} hookName  The name of the hook to modify.
 * @param {string} namespace The unique namespace identifying the callback in the
 *                           form `vendor/plugin/function`.
 *
 * @return {number | undefined} The number of callbacks removed.
 */

/**
 * Returns a function which, when invoked, will remove a specified hook or all
 * hooks by the given name.
 *
 * @param {import('.').Hooks}    hooks             Hooks instance.
 * @param {import('.').StoreKey} storeKey
 * @param {boolean}              [removeAll=false] Whether to remove all callbacks for a hookName,
 *                                                 without regard to namespace. Used to create
 *                                                 `removeAll*` functions.
 *
 * @return {RemoveHook} Function that removes hooks.
 */

function createRemoveHook(hooks, storeKey) {
  let removeAll = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;
  return function removeHook(hookName, namespace) {
    const hooksStore = hooks[storeKey];

    if (!validateHookName(hookName)) {
      return;
    }

    if (!removeAll && !validateNamespace(namespace)) {
      return;
    } // Bail if no hooks exist by this name


    if (!hooksStore[hookName]) {
      return 0;
    }

    let handlersRemoved = 0;

    if (removeAll) {
      handlersRemoved = hooksStore[hookName].handlers.length;
      hooksStore[hookName] = {
        runs: hooksStore[hookName].runs,
        handlers: []
      };
    } else {
      // Try to find the specified callback to remove.
      const handlers = hooksStore[hookName].handlers;

      for (let i = handlers.length - 1; i >= 0; i--) {
        if (handlers[i].namespace === namespace) {
          handlers.splice(i, 1);
          handlersRemoved++; // This callback may also be part of a hook that is
          // currently executing.  If the callback we're removing
          // comes after the current callback, there's no problem;
          // otherwise we need to decrease the execution index of any
          // other runs by 1 to account for the removed element.

          hooksStore.__current.forEach(hookInfo => {
            if (hookInfo.name === hookName && hookInfo.currentIndex >= i) {
              hookInfo.currentIndex--;
            }
          });
        }
      }
    }

    if (hookName !== 'hookRemoved') {
      hooks.doAction('hookRemoved', hookName, namespace);
    }

    return handlersRemoved;
  };
}

/**
 * @callback HasHook
 *
 * Returns whether any handlers are attached for the given hookName and optional namespace.
 *
 * @param {string} hookName    The name of the hook to check for.
 * @param {string} [namespace] Optional. The unique namespace identifying the callback
 *                             in the form `vendor/plugin/function`.
 *
 * @return {boolean} Whether there are handlers that are attached to the given hook.
 */

/**
 * Returns a function which, when invoked, will return whether any handlers are
 * attached to a particular hook.
 *
 * @param {import('.').Hooks}    hooks    Hooks instance.
 * @param {import('.').StoreKey} storeKey
 *
 * @return {HasHook} Function that returns whether any handlers are
 *                   attached to a particular hook and optional namespace.
 */
function createHasHook(hooks, storeKey) {
  return function hasHook(hookName, namespace) {
    const hooksStore = hooks[storeKey]; // Use the namespace if provided.

    if ('undefined' !== typeof namespace) {
      return hookName in hooksStore && hooksStore[hookName].handlers.some(hook => hook.namespace === namespace);
    }

    return hookName in hooksStore;
  };
}

/**
 * Returns a function which, when invoked, will execute all callbacks
 * registered to a hook of the specified type, optionally returning the final
 * value of the call chain.
 *
 * @param {import('.').Hooks}    hooks                  Hooks instance.
 * @param {import('.').StoreKey} storeKey
 * @param {boolean}              [returnFirstArg=false] Whether each hook callback is expected to
 *                                                      return its first argument.
 *
 * @return {(hookName:string, ...args: unknown[]) => unknown} Function that runs hook callbacks.
 */
function createRunHook(hooks, storeKey) {
  let returnFirstArg = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;
  return function runHooks(hookName) {
    const hooksStore = hooks[storeKey];

    if (!hooksStore[hookName]) {
      hooksStore[hookName] = {
        handlers: [],
        runs: 0
      };
    }

    hooksStore[hookName].runs++;
    const handlers = hooksStore[hookName].handlers; // The following code is stripped from production builds.

    for (var _len = arguments.length, args = new Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
      args[_key - 1] = arguments[_key];
    }

    if (!handlers || !handlers.length) {
      return returnFirstArg ? args[0] : undefined;
    }

    const hookInfo = {
      name: hookName,
      currentIndex: 0
    };

    hooksStore.__current.push(hookInfo);

    while (hookInfo.currentIndex < handlers.length) {
      const handler = handlers[hookInfo.currentIndex];
      const result = handler.callback.apply(null, args);

      if (returnFirstArg) {
        args[0] = result;
      }

      hookInfo.currentIndex++;
    }

    hooksStore.__current.pop();

    if (returnFirstArg) {
      return args[0];
    }
  };
}

/**
 * Returns a function which, when invoked, will return the name of the
 * currently running hook, or `null` if no hook of the given type is currently
 * running.
 *
 * @param {import('.').Hooks}    hooks    Hooks instance.
 * @param {import('.').StoreKey} storeKey
 *
 * @return {() => string | null} Function that returns the current hook name or null.
 */
function createCurrentHook(hooks, storeKey) {
  return function currentHook() {
    var _hooksStore$__current, _hooksStore$__current2;

    const hooksStore = hooks[storeKey];
    return (_hooksStore$__current = (_hooksStore$__current2 = hooksStore.__current[hooksStore.__current.length - 1]) === null || _hooksStore$__current2 === void 0 ? void 0 : _hooksStore$__current2.name) !== null && _hooksStore$__current !== void 0 ? _hooksStore$__current : null;
  };
}

/**
 * @callback DoingHook
 * Returns whether a hook is currently being executed.
 *
 * @param {string} [hookName] The name of the hook to check for.  If
 *                            omitted, will check for any hook being executed.
 *
 * @return {boolean} Whether the hook is being executed.
 */

/**
 * Returns a function which, when invoked, will return whether a hook is
 * currently being executed.
 *
 * @param {import('.').Hooks}    hooks    Hooks instance.
 * @param {import('.').StoreKey} storeKey
 *
 * @return {DoingHook} Function that returns whether a hook is currently
 *                     being executed.
 */
function createDoingHook(hooks, storeKey) {
  return function doingHook(hookName) {
    const hooksStore = hooks[storeKey]; // If the hookName was not passed, check for any current hook.

    if ('undefined' === typeof hookName) {
      return 'undefined' !== typeof hooksStore.__current[0];
    } // Return the __current hook.


    return hooksStore.__current[0] ? hookName === hooksStore.__current[0].name : false;
  };
}

/**
 * Internal dependencies
 */
/**
 * @callback DidHook
 *
 * Returns the number of times an action has been fired.
 *
 * @param {string} hookName The hook name to check.
 *
 * @return {number | undefined} The number of times the hook has run.
 */

/**
 * Returns a function which, when invoked, will return the number of times a
 * hook has been called.
 *
 * @param {import('.').Hooks}    hooks    Hooks instance.
 * @param {import('.').StoreKey} storeKey
 *
 * @return {DidHook} Function that returns a hook's call count.
 */

function createDidHook(hooks, storeKey) {
  return function didHook(hookName) {
    const hooksStore = hooks[storeKey];

    if (!validateHookName(hookName)) {
      return;
    }

    return hooksStore[hookName] && hooksStore[hookName].runs ? hooksStore[hookName].runs : 0;
  };
}

/**
 * Internal dependencies
 */
/**
 * Internal class for constructing hooks. Use `createHooks()` function
 *
 * Note, it is necessary to expose this class to make its type public.
 *
 * @private
 */

class _Hooks {
  constructor() {
    /** @type {import('.').Store} actions */
    this.actions = Object.create(null);
    this.actions.__current = [];
    /** @type {import('.').Store} filters */

    this.filters = Object.create(null);
    this.filters.__current = [];
    this.addAction = createAddHook(this, 'actions');
    this.addFilter = createAddHook(this, 'filters');
    this.removeAction = createRemoveHook(this, 'actions');
    this.removeFilter = createRemoveHook(this, 'filters');
    this.hasAction = createHasHook(this, 'actions');
    this.hasFilter = createHasHook(this, 'filters');
    this.removeAllActions = createRemoveHook(this, 'actions', true);
    this.removeAllFilters = createRemoveHook(this, 'filters', true);
    this.doAction = createRunHook(this, 'actions');
    this.applyFilters = createRunHook(this, 'filters', true);
    this.currentAction = createCurrentHook(this, 'actions');
    this.currentFilter = createCurrentHook(this, 'filters');
    this.doingAction = createDoingHook(this, 'actions');
    this.doingFilter = createDoingHook(this, 'filters');
    this.didAction = createDidHook(this, 'actions');
    this.didFilter = createDidHook(this, 'filters');
  }

}
/** @typedef {_Hooks} Hooks */

/**
 * Returns an instance of the hooks object.
 *
 * @return {Hooks} A Hooks instance.
 */

function createHooks() {
  return new _Hooks();
}

/**
 * Internal dependencies
 */
/** @typedef {(...args: any[])=>any} Callback */

/**
 * @typedef Handler
 * @property {Callback} callback  The callback
 * @property {string}   namespace The namespace
 * @property {number}   priority  The namespace
 */

/**
 * @typedef Hook
 * @property {Handler[]} handlers Array of handlers
 * @property {number}    runs     Run counter
 */

/**
 * @typedef Current
 * @property {string} name         Hook name
 * @property {number} currentIndex The index
 */

/**
 * @typedef {Record<string, Hook> & {__current: Current[]}} Store
 */

/**
 * @typedef {'actions' | 'filters'} StoreKey
 */

/**
 * @typedef {import('./createHooks').Hooks} Hooks
 */

const defaultHooks = createHooks();

export { Tannin as T, defaultHooks as d, memize_1 as m, sprintf as s };
