"use strict";

const assert = require("node:assert/strict");

const FakeEvent = require("./zjquery_event.cjs");

function split_words(x) {
    return Array.isArray(x) ? x : x.trim().split(/\s+/);
}

const ignore_missing = Symbol("ignore_missing");

const reject_missing_handler = {
    has(target, property) {
        if (!(Reflect.has(target, property) || target[ignore_missing]?.(property))) {
            throw new TypeError(`unknown property ${property} of mock ${target.constructor.name}`);
        }
        return Reflect.has(target, property);
    },
    get(target, property, receiver) {
        if (!(Reflect.has(target, property) || target[ignore_missing]?.(property))) {
            throw new TypeError(`unknown property ${property} of mock ${target.constructor.name}`);
        }
        return Reflect.get(target, property, receiver);
    },
    ownKeys(target) {
        throw new TypeError(`enumerating properties of mock ${target.constructor.name}`);
    },
};

class RejectMissing {
    constructor() {
        return new Proxy(this, reject_missing_handler);
    }
}

class FakeClassList extends RejectMissing {
    #list = new Set();

    contains(class_name) {
        return this.#list.has(class_name);
    }
    add(...class_names) {
        for (const class_name of class_names) {
            this.#list.add(String(class_name));
        }
    }
    remove(...class_names) {
        for (const class_name of class_names) {
            this.#list.delete(String(class_name));
        }
    }
    toggle(class_name, state = !this.#list.has(String(class_name))) {
        if (state) {
            this.#list.add(String(class_name));
        } else {
            this.#list.delete(String(class_name));
        }
    }
}

class FakeStyle extends RejectMissing {
    #style = new Map();

    get length() {
        return this.#style.size;
    }
    getPropertyValue(name) {
        return this.#style.get(name) ?? "";
    }
    setProperty(name, value) {
        this.#style.set(name, String(value));
    }
    removeProperty(name) {
        const value = this.#style.get(name) ?? "";
        this.#style.delete(name);
        return value;
    }
}

class FakeElementState {
    closest_results = new Map();
    computed_style = new FakeStyle();
    event_handlers = new Map();
    delegated_event_handlers = new Map();
    is_focused = false;
    jquery_data = new Map();
    match_results = new Map([["*", true]]);
    parents_results = new Map();
    query_results = new Map();
    selector = undefined;
    shown = false;
}

const fake_element_state = new WeakMap();

function camel(s) {
    return s.replaceAll(/-([a-z])/g, (_, c) => c.toUpperCase());
}

function decamel(s) {
    return s.replaceAll(/[A-Z]/g, (c) => `-${c.toLowerCase()}`);
}

function normalize_attribute(name) {
    return String(name).replaceAll(/[A-Z]/g, (c) => c.toLowerCase());
}

function attribute_to_dataset_key(name) {
    assert.ok(name.startsWith("data-"));
    return camel(name.slice("data-".length));
}

function is_dataset_key(key) {
    return !/-[a-z]/.test(key);
}

function dataset_key_to_attribute(key) {
    return `data-${decamel(key)}`;
}

class FakeDataSet {
    constructor(element) {
        return new Proxy(this, {
            get(target, key, receiver) {
                return (
                    (is_dataset_key(key)
                        ? element.getAttribute(dataset_key_to_attribute(key))
                        : null) ?? Reflect.get(target, key, receiver)
                );
            },
            has(_target, key) {
                return is_dataset_key(key) && element.hasAttribute(dataset_key_to_attribute(key));
            },
            set(_target, key, value) {
                assert.ok(is_dataset_key(key));
                element.setAttribute(dataset_key_to_attribute(key), value);
                return true;
            },
            deleteProperty(_target, key) {
                if (is_dataset_key(key)) {
                    element.removeAttribute(dataset_key_to_attribute(key));
                }
                return true;
            },
            ownKeys(_target) {
                return element
                    .getAttributeNames()
                    .filter((name) => name.startsWith("data-"))
                    .map((name) => attribute_to_dataset_key(name));
            },
        });
    }
}

// https://api.jquery.com/css/
const auto_px =
    /^(Border(Top|Right|Bottom|Left)?(Width)?|(Margin|Padding)?(Top|Right|Bottom|Left)?|(Min|Max)?(Width|Height))$/;

class FakeElement extends RejectMissing {
    _tippy = undefined;
    classList = new FakeClassList();
    dataset = new FakeDataSet(this);
    innerHTML = "never-been-set";
    selectionEnd = undefined;
    selectionStart = undefined;
    style = new FakeStyle();
    textContent = "never-been-set";
    value = undefined;

    #attributes = new Map();

    constructor() {
        super();
        fake_element_state.set(this, new FakeElementState());
    }
    append() {}
    closest(selector) {
        const state = fake_element_state.get(this);
        if (!state.closest_results.has(selector)) {
            throw new Error(
                `You need to call $(${JSON.stringify(state.selector)}).set_closest_results(${JSON.stringify(selector)}, ...)`,
            );
        }
        return state.closest_results.get(selector);
    }
    hasAttribute(name) {
        return this.#attributes.has(normalize_attribute(name));
    }
    getAttribute(name) {
        return this.#attributes.get(normalize_attribute(name)) ?? null;
    }
    getAttributeNames() {
        return this.#attributes.keys();
    }
    matches(selector) {
        const state = fake_element_state.get(this);
        if (!state.match_results.has(selector)) {
            throw new Error(
                `You need to call $(${JSON.stringify(state.selector)}).set_matches(${JSON.stringify(selector)}, boolean)`,
            );
        }
        return state.match_results.get(selector);
    }
    querySelectorAll(selector) {
        const state = fake_element_state.get(this);
        const results = state.query_results.get(selector);
        if (results) {
            return results;
        }
        throw new Error(
            `You need to call $(${JSON.stringify(state.selector)}).set_find_results(${JSON.stringify(selector)}, ...).`,
        );
    }
    removeAttribute(name) {
        this.#attributes.delete(normalize_attribute(name));
    }
    replaceChildren(...children) {
        assert.equal(children.length, 0, "zjquery does not support this replaceChildren() call");
        fake_element_state.get(this).query_results.clear();
        this.innerHTML = "";
    }
    setAttribute(name, value) {
        this.#attributes.set(normalize_attribute(name), String(value));
    }
    setSelectionRange(start, end) {
        this.selectionStart = start;
        this.selectionEnd = end;
    }
    to_$() {
        return new exports.FakeJQuery([this]);
    }
}

exports.default_element = function (selector) {
    const element = new FakeElement();
    fake_element_state.get(element).selector = selector;
    if (selector[0] === "<") {
        element.innerHTML = selector;
    }
    return element;
};

function dom_args(args) {
    return args.flat().flatMap((arg) => {
        assert.equal(typeof arg, "object");
        return arg.__zjquery ? [...arg] : [arg];
    });
}

exports.FakeJQuery = class extends RejectMissing {
    [Symbol.iterator] = Array.prototype.values;
    __zjquery = true;

    constructor(elements) {
        super();
        this.length = elements.length;
        for (const [i, element] of elements.entries()) {
            this[i] = element;
        }
    }

    get selector() {
        assert.equal(this.length, 1);
        return fake_element_state.get(this[0]).selector;
    }

    addClass(class_names) {
        class_names = split_words(class_names);
        for (const element of this) {
            element.classList.add(...class_names);
        }
        return this;
    }
    after(...args) {
        assert.equal(this.length, 1);
        this[0].after(...dom_args(args));
        return this;
    }
    append(...args) {
        assert.equal(this.length, 1);
        this[0].append(...dom_args(args));
        return this;
    }
    attr(name, ...args) {
        assert.notEqual(name, undefined);
        if (args.length === 0) {
            return 0 in this ? (this[0].getAttribute(name) ?? undefined) : undefined;
        }
        const [value] = args;
        for (const element of this) {
            element.setAttribute(name, value);
        }
        return this;
    }
    before(...args) {
        assert.equal(this.length, 1);
        this[0].before(...dom_args(args));
        return this;
    }
    caret(...args) {
        if (args.length === 0) {
            return this[0]?.selectionStart;
        }
        assert.equal(typeof args[0], "number", "zjquery does not support this caret() call");
        for (const element of this) {
            element.setSelectionRange(args[0], args[0]);
        }
        return this;
    }
    children(selector = "*") {
        return new exports.FakeJQuery(
            [...this].flatMap((element) =>
                [...element.children].filter((child) => child.matches(selector)),
            ),
        );
    }
    closest(selector) {
        return new exports.FakeJQuery(
            [...this].flatMap((element) => element.closest(selector) ?? []),
        );
    }
    contents() {
        return new exports.FakeJQuery([...this].flatMap((element) => [...element.childNodes]));
    }
    css(property, ...args) {
        if (args.length === 0 && typeof property === "string") {
            if (!(0 in this)) {
                return undefined;
            }
            return fake_element_state
                .get(this[0])
                .computed_style.getPropertyValue(decamel(property));
        }

        if (args.length === 0 && Array.isArray(property)) {
            if (!(0 in this)) {
                return undefined;
            }
            const state = fake_element_state.get(this[0]);
            return Object.fromEntries(
                property.map((key) => [key, state.computed_style.getPropertyValue(decamel(key))]),
            );
        }

        for (const element of this) {
            const properties = typeof property === "string" ? {[property]: args[0]} : property;
            for (const [key, value] of Object.entries(properties)) {
                element.style.setProperty(
                    decamel(key),
                    typeof value === "number" &&
                        auto_px.test(camel(key).replace(/^./, (c) => c.toUpperCase()))
                        ? `${value}px`
                        : value,
                );
            }
        }
        return this;
    }
    data(key, ...args) {
        if (args.length === 0) {
            if (!(0 in this)) {
                return undefined;
            }
            const state = fake_element_state.get(this[0]);
            if (state.jquery_data.has(key)) {
                return state.jquery_data.get(key);
            }
            let value = this[0].getAttribute(dataset_key_to_attribute(key));

            if (value === null) {
                return null;
            }

            if (/^true$|^false$|^null$|^{.*}$|^\[.*]$/s.test(value)) {
                try {
                    value = JSON.parse(value);
                } catch {
                    // use the unparsed value
                }
            } else if (Number(value).toString() === value) {
                value = Number(value);
            }

            state.jquery_data.set(key, value);
            return value;
        }

        const [value] = args;
        for (const element of this) {
            fake_element_state.get(element).jquery_data.set(key, value);
        }
        return this;
    }
    detach() {
        for (const element of this) {
            element.remove();
        }
        return this;
    }
    each(callback) {
        for (const [index, element] of [...this].entries()) {
            callback.call(element, index, element);
        }
        return this;
    }
    empty() {
        for (const element of this) {
            element.replaceChildren();
        }
        return this;
    }
    expectOne() {
        // silently do nothing
        return this;
    }
    fadeIn() {
        for (const element of this) {
            fake_element_state.get(element).shown = true;
        }
        return this;
    }
    fadeOut(_duration, callback) {
        for (const element of this) {
            fake_element_state.get(element).shown = false;
            callback.call();
        }
        return this;
    }
    fadeTo() {
        return this;
    }
    filter(arg) {
        return new exports.FakeJQuery(
            [...this].filter(
                typeof arg === "function"
                    ? (element, index) => arg.call(element, index, element)
                    : (element) => element.matches(arg),
            ),
        );
    }
    find(selector) {
        return new exports.FakeJQuery(
            [...this].flatMap((element) => [...element.querySelectorAll(selector)]),
        );
    }
    get(index) {
        return index === undefined ? [...this] : this[index];
    }
    get_on_handler(event_type, child_selector) {
        assert.ok(0 in this);
        const state = fake_element_state.get(this[0]);

        if (child_selector === undefined) {
            const handler = state.event_handlers.get(event_type);
            assert.ok(handler !== undefined, `no ${event_type} handler for ${state.selector}`);
            return handler;
        }

        const handler = state.delegated_event_handlers.get(child_selector)?.get(event_type);
        assert.ok(
            handler !== undefined,
            `no ${event_type} handler for ${state.selector} ${child_selector}`,
        );
        return handler;
    }
    hasClass(class_name) {
        return [...this].some((element) => element.classList.contains(class_name));
    }
    height(...args) {
        if (args.length === 0) {
            if (!(0 in this)) {
                return undefined;
            }
            const state = fake_element_state.get(this[0]);
            const height = state.computed_style.getPropertyValue("height");
            assert.notEqual(
                height,
                "",
                `Please call $(${JSON.stringify(state.selector)}).set_height`,
            );
            assert.ok(height.endsWith("px"));
            return Number(height.slice(0, -"px".length));
        }
        for (const element of this) {
            element.style.setProperty(
                "height",
                typeof args[0] === "number" ? `${args[0]}px` : args[0],
            );
        }
        return this;
    }
    hide() {
        for (const element of this) {
            fake_element_state.get(element).shown = false;
        }
        return this;
    }
    html(...args) {
        if (args.length === 0) {
            return this[0]?.innerHTML;
        }

        const [arg] = args;
        assert.equal(typeof arg, "string");
        for (const element of this) {
            element.innerHTML = arg;
        }
        return this;
    }
    insertAfter(...args) {
        args = dom_args(args);
        assert.equal(args.length, 1);
        args[0].after(...this);
        return this;
    }
    insertBefore(...args) {
        args = dom_args(args);
        assert.equal(args.length, 1);
        args[0].before(...this);
        return this;
    }
    is(arg) {
        switch (arg) {
            case ":visible":
                return [...this].some((element) => fake_element_state.get(element).shown);
            case ":focus":
                return this.is_focused();
            /* istanbul ignore next */
            default:
                return [...this].some((element) => element.matches(arg));
        }
    }
    is_focused() {
        // is_focused is not a jQuery thing; this is
        // for our testing
        assert.ok(0 in this);
        return fake_element_state.get(this[0]).is_focused;
    }
    last() {
        return new exports.FakeJQuery([...this].slice(-1));
    }
    next(selector = "*") {
        return new exports.FakeJQuery(
            [...this]
                .map((element) => element.nextElementSibling)
                .filter((next) => next !== null && next.matches(selector)),
        );
    }
    off(event_type, ...args) {
        if (args.length === 0) {
            for (const element of this) {
                const state = fake_element_state.get(element);
                state.event_handlers.delete(event_type);
            }
        } else {
            // In the Zulip codebase we never use this form of
            // .off in code that we test: $(...).off('click', child_sel);
            //
            // So we don't support this for now.
            /* istanbul ignore next */
            throw new Error("zjquery does not support this call sequence");
        }
        return this;
    }
    on(event_type, ...args) {
        // parameters will either be
        //    (event_type, handler) or
        //    (event_type, sel, handler)
        if (args.length === 1) {
            const [handler] = args;
            for (const element of this) {
                const state = fake_element_state.get(element);
                /* istanbul ignore if */
                if (state.event_handlers.has(event_type)) {
                    console.info("\nEither the app or the test can be at fault here..");
                    console.info("(sometimes you just want to call $.clear_all_elements();)\n");
                    throw new Error("dup " + event_type + " handler for " + state.selector);
                }

                state.event_handlers.set(event_type, handler);
            }
        } else {
            assert.equal(args.length, 2, "wrong number of arguments passed in");

            const [sel, handler] = args;
            assert.equal(typeof sel, "string", "String selectors expected here.");
            assert.equal(typeof handler, "function", "An handler function expected here.");

            for (const element of this) {
                const state = fake_element_state.get(element);
                if (!state.delegated_event_handlers.has(sel)) {
                    state.delegated_event_handlers.set(sel, new Map());
                }
                const child_on = state.delegated_event_handlers.get(sel);

                assert.ok(
                    !child_on.has(event_type),
                    `dup ${event_type} handler for ${state.selector} ${sel}`,
                );

                child_on.set(event_type, handler);
            }
        }
        return this;
    }
    /* istanbul ignore next */
    one(event_type, handler) {
        return this.on(
            event_type,
            /* istanbul ignore next */ function (...args) {
                this.off(event_type);
                return handler.call(this, ...args);
            },
        );
    }
    outerHeight() {
        if (!(0 in this)) {
            return undefined;
        }
        const state = fake_element_state.get(this[0]);
        const height = state.computed_style.getPropertyValue("height");
        if (height === "") {
            return undefined;
        }
        assert.ok(height.endsWith("px"));
        return Number(height.slice(0, -2));
    }
    parent(selector = "*") {
        return new exports.FakeJQuery(
            [...this]
                .map((element) => element.parentNode)
                .filter((parent) => parent !== null && parent.matches(selector)),
        );
    }
    parents(selector = "*") {
        return new exports.FakeJQuery(
            [...this].flatMap((element) => {
                const state = fake_element_state.get(element);
                if (!state.parents_results.has(selector)) {
                    throw new Error(
                        `You need to call $(${JSON.stringify(state.selector)}).set_parents_result(${JSON.stringify(selector)}, ...)`,
                    );
                }
                return state.parents_results.get(selector);
            }),
        );
    }
    prepend(...args) {
        assert.equal(this.length, 1);
        this[0].prepend(...dom_args(args));
        return this;
    }
    prev(selector = "*") {
        return new exports.FakeJQuery(
            [...this]
                .map((element) => element.previousElementSibling)
                .filter((prev) => prev !== null && prev.matches(selector)),
        );
    }
    prop(name, ...args) {
        if (args.length === 0) {
            return this[0]?.[name];
        }
        const [value] = args;
        for (const element of this) {
            element[name] = value;
        }
        return this;
    }
    range(...args) {
        if (args.length === 0) {
            return 0 in this
                ? {
                      start: this[0].selectionStart,
                      end: this[0].selectionEnd,
                      length: this[0].selectionEnd - this[0].selectionStart,
                      text: this[0].value.slice(this[0].selectionStart, this[0].selectionEnd),
                  }
                : undefined;
        }
        assert.equal(typeof args[0], "number", "zjquery does not support this range() call");
        for (const element of this) {
            element.setSelectionRange(args[0], args[1]);
        }
        return this;
    }
    removeAttr(name) {
        for (const element of this) {
            element.removeAttribute(name);
        }
        return this;
    }
    removeClass(class_names) {
        class_names = split_words(class_names);
        for (const element of this) {
            element.classList.remove(...class_names);
        }
        return this;
    }
    remove() {
        for (const element of this) {
            element.remove();
            fake_element_state.get(element).jquery_data.clear();
        }
        return this;
    }
    removeData(keys) {
        keys = split_words(keys);
        for (const element of this) {
            const state = fake_element_state.get(element);
            for (const key of keys) {
                state.jquery_data.delete(key);
            }
        }
        return this;
    }
    replaceWith(...args) {
        assert.equal(this.length, 1);
        this[0].replaceWith(...dom_args(args));
        return this;
    }
    set_children(elements) {
        assert.equal(this.length, 1);
        this[0].children = [...elements];
    }
    set_closest_results(selector, elements) {
        assert.equal(this.length, 1);
        fake_element_state.get(this[0]).closest_results.set(selector, elements[0] ?? null);
    }
    set_contents(nodes) {
        assert.equal(this.length, 1);
        this[0].childNodes = [...nodes];
    }
    set_find_results(selector, elements) {
        assert.equal(this.length, 1);
        fake_element_state.get(this[0]).query_results.set(selector, [...elements]);
    }
    set_height(fake_height) {
        for (const element of this) {
            fake_element_state
                .get(element)
                .computed_style.setProperty(
                    "height",
                    typeof fake_height === "number" ? `${fake_height}px` : fake_height,
                );
        }
    }
    set_matches(selector, value) {
        assert.equal(this.length, 1);
        fake_element_state.get(this[0]).match_results.set(selector, value);
    }
    set_next($result) {
        assert.equal(this.length, 1);
        assert.equal($result.length, 1);
        this[0].nextElementSibling = $result[0];
    }
    set_parent($parent_elem) {
        assert.equal(this.length, 1);
        assert.equal($parent_elem.length, 1);
        this[0].parentNode = $parent_elem[0];
    }
    set_parents_result(selector, elements) {
        assert.equal(this.length, 1);
        fake_element_state.get(this[0]).parents_results.set(selector, [...elements]);
    }
    set_prev($result) {
        assert.equal(this.length, 1);
        assert.equal($result.length, 1);
        this[0].previousElementSibling = $result[0];
    }
    show() {
        for (const element of this) {
            fake_element_state.get(element).shown = true;
        }
        return this;
    }
    text(...args) {
        if (args.length === 0) {
            return [...this].map((element) => element.textContent).join("");
        }
        const [arg] = args;
        for (const [i, element] of [...this].entries()) {
            element.textContent =
                (typeof arg === "function"
                    ? arg.call(element, i, element.textContent)
                    : arg
                )?.toString() ?? "";
        }
        return this;
    }
    // Used by zjquery to support $($x) === $x
    to_$() {
        return new exports.FakeJQuery([...this]);
    }
    toggle(show) {
        assert.ok([true, false].includes(show));
        for (const element of this) {
            fake_element_state.get(element).shown = show;
        }
        return this;
    }
    toggleClass(class_names, add) {
        class_names = split_words(class_names);
        for (const element of this) {
            for (const class_name of class_names) {
                element.classList.toggle(class_name, add);
            }
        }
        return this;
    }
    trigger(event_arg, extra_args) {
        for (const element of this) {
            const event = new FakeEvent(
                typeof event_arg === "string" ? event_arg : event_arg.type,
                {
                    target: element,
                    currentTarget: element,
                    ...event_arg,
                },
            );
            const state = fake_element_state.get(element);
            const func = state.event_handlers.get(event.type);

            if (func) {
                // It's possible that test code will trigger events
                // that haven't been set up yet, but we are trying to
                // eventually deprecate trigger in our codebase, so for
                // now we just let calls to trigger silently do nothing.
                // (And I think actual jQuery would do the same thing.)
                func.call(
                    element,
                    event,
                    ...(Array.isArray(extra_args) ? extra_args : [extra_args]),
                );
            }

            if (event.type === "focus" || event.type === "focusin") {
                state.is_focused = true;
            } else if (event.type === "blur" || event.type === "focusout") {
                state.is_focused = false;
            }
        }
        return this;
    }
    unwrap(...args) {
        assert.equal(args.length, 0, "zjquery does not support this unwrap() call");
        for (const element of this) {
            element.parentNode.replaceWith(element.childNodes);
        }
        return this;
    }
    val(...args) {
        if (args.length === 0) {
            return 0 in this ? (this[0].value ?? "") : undefined;
        }
        const [value] = args;
        for (const element of this) {
            element.value = value;
        }
        return this;
    }
    visible() {
        return [...this].some((element) => fake_element_state.get(element).shown);
    }
    [ignore_missing](property) {
        return [
            `${Number(property) >>> 0}`, // eslint-disable-line no-bitwise
            "__esModule",
            "stack",
        ].includes(property);
    }
};