import { action, IReactionDisposer, reaction } from "mobx";
import { baseKeymap } from "prosemirror-commands";
import { history, redo, undo } from "prosemirror-history";
import { keymap } from "prosemirror-keymap";
import { EditorState, Transaction, NodeSelection } from "prosemirror-state";
import { EditorView } from "prosemirror-view";
import { schema } from "./RichTextSchema";
import { Schema, NodeType } from "prosemirror-model";
import React = require("react");
import "./TooltipTextMenu.scss";
const { toggleMark, setBlockType, wrapIn } = require("prosemirror-commands");
import { library } from '@fortawesome/fontawesome-svg-core';
import { wrapInList, bulletList } from 'prosemirror-schema-list';
import { faListUl } from '@fortawesome/free-solid-svg-icons';
import { FieldViewProps } from "../views/nodes/FieldView";
import { throwStatement } from "babel-types";


//appears above a selection of text in a RichTextBox to give user options such as Bold, Italics, etc.
export class TooltipTextMenu {

    private tooltip: HTMLElement;
    private editorProps: FieldViewProps;

    constructor(view: EditorView, editorProps: FieldViewProps) {
        this.editorProps = editorProps;
        this.tooltip = document.createElement("div");
        this.tooltip.className = "tooltipMenu";

        //add the div which is the tooltip
        view.dom.parentNode!.parentNode!.appendChild(this.tooltip);

        //add additional icons
        library.add(faListUl);

        //add the buttons to the tooltip
        let items = [
            { command: toggleMark(schema.marks.strong), dom: this.icon("B", "strong") },
            { command: toggleMark(schema.marks.em), dom: this.icon("i", "em") },
            { command: toggleMark(schema.marks.underline), dom: this.icon("U", "underline") },
            { command: toggleMark(schema.marks.strikethrough), dom: this.icon("S", "strikethrough") },
            { command: toggleMark(schema.marks.superscript), dom: this.icon("s", "superscript") },
            { command: toggleMark(schema.marks.subscript), dom: this.icon("s", "subscript") },
            //this doesn't work currently - look into notion of active block
            { command: wrapInList(schema.nodes.bullet_list), dom: this.icon(":", "bullets") },
        ];
        items.forEach(({ dom }) => this.tooltip.appendChild(dom));

        //pointer down handler to activate button effects
        this.tooltip.addEventListener("pointerdown", e => {
            e.preventDefault();
            view.focus();
            items.forEach(({ command, dom }) => {
                if (dom.contains(e.target as Node)) {
                    let active = command(view.state, view.dispatch, view);
                    //uncomment this if we want the bullet button to disappear if current selection is bulleted
                    // dom.style.display = active ? "" : "none"
                }
            });
        });

        this.update(view, undefined);
    }

    // Helper function to create menu icons
    icon(text: string, name: string) {
        let span = document.createElement("span");
        span.className = "menuicon " + name;
        span.title = name;
        span.textContent = text;
        return span;
    }

    //adapted this method - use it to check if block has a tag (ie bulleting)
    blockActive(type: NodeType<Schema<string, string>>, state: EditorState) {
        let attrs = {};

        if (state.selection instanceof NodeSelection) {
            const sel: NodeSelection = state.selection;
            let $from = sel.$from;
            let to = sel.to;
            let node = sel.node;

            if (node) {
                return node.hasMarkup(type, attrs);
            }

            return to <= $from.end() && $from.parent.hasMarkup(type, attrs);
        }
    }

    //this doesn't currently work but could be used to use icons for buttons
    unorderedListIcon(): HTMLSpanElement {
        let span = document.createElement("span");
        let icon = document.createElement("FontAwesomeIcon");
        icon.className = "menuicon fa fa-smile-o";
        span.appendChild(icon);
        return span;
    }

    // Create an icon for a heading at the given level
    heading(level: number) {
        return {
            command: setBlockType(schema.nodes.heading, { level }),
            dom: this.icon("H" + level, "heading")
        };
    }

    //updates the tooltip menu when the selection changes
    update(view: EditorView, lastState: EditorState | undefined) {
        let state = view.state;
        // Don't do anything if the document/selection didn't change
        if (lastState && lastState.doc.eq(state.doc) &&
            lastState.selection.eq(state.selection)) return;

        // Hide the tooltip if the selection is empty
        if (state.selection.empty) {
            this.tooltip.style.display = "none";
            return;
        }

        // Otherwise, reposition it and update its content
        this.tooltip.style.display = "";
        let { from, to } = state.selection;
        let start = view.coordsAtPos(from), end = view.coordsAtPos(to);
        // The box in which the tooltip is positioned, to use as base
        let box = this.tooltip.offsetParent!.getBoundingClientRect();
        // Find a center-ish x position from the selection endpoints (when
        // crossing lines, end may be more to the left)
        let left = Math.max((start.left + end.left) / 2, start.left + 3);
        this.tooltip.style.left = (left - box.left) * this.editorProps.ScreenToLocalTransform().Scale + "px";
        let width = Math.abs(start.left - end.left) / 2 * this.editorProps.ScreenToLocalTransform().Scale;
        let mid = Math.min(start.left, end.left) + width;

        //THIS WIDTH IS 15 * NUMBER OF ICONS + 15
        this.tooltip.style.width = 122 + "px";
        this.tooltip.style.bottom = (box.bottom - start.top) * this.editorProps.ScreenToLocalTransform().Scale + "px";
    }

    destroy() { this.tooltip.remove(); }
}