/*eslint max-lines: ["warn", {"max": 300, "skipBlankLines": true, "skipComments": true}]*/
require('./editor.less');
const React = require('react');
const createClass = require('create-react-class');
const _ = require('lodash');
const cx = require('classnames');
const dedent = require('dedent-tabs').default;

const CodeEditor = require('naturalcrit/codeEditor/codeEditor.jsx');
const SnippetBar = require('./snippetbar/snippetbar.jsx');
const MetadataEditor = require('./metadataEditor/metadataEditor.jsx');

const SNIPPETBAR_HEIGHT = 25;
const DEFAULT_STYLE_TEXT = dedent`
				/*=======---  Example CSS styling  ---=======*/
				/* Any CSS here will apply to your document! */

				.myExampleClass {
					color: black;
				}`;

const splice = function(str, index, inject){
	return str.slice(0, index) + inject + str.slice(index);
};



const Editor = createClass({
	displayName : 'Editor',
	getDefaultProps : function() {
		return {
			brew : {
				text  : '',
				style : ''
			},

			onTextChange  : ()=>{},
			onStyleChange : ()=>{},
			onMetaChange  : ()=>{},

			renderer : 'legacy'
		};
	},
	getInitialState : function() {
		return {
			view : 'text' //'text', 'style', 'meta'
		};
	},

	isText  : function() {return this.state.view == 'text';},
	isStyle : function() {return this.state.view == 'style';},
	isMeta  : function() {return this.state.view == 'meta';},

	componentDidMount : function() {
		this.updateEditorSize();
		this.highlightCustomMarkdown();
		window.addEventListener('resize', this.updateEditorSize);
	},

	componentWillUnmount : function() {
		window.removeEventListener('resize', this.updateEditorSize);
	},

	componentDidUpdate : function() {
		this.highlightCustomMarkdown();
	},

	updateEditorSize : function() {
		if(this.refs.codeEditor) {
			let paneHeight = this.refs.main.parentNode.clientHeight;
			paneHeight -= SNIPPETBAR_HEIGHT + 1;
			this.refs.codeEditor.codeMirror.setSize(null, paneHeight);
		}
	},

	handleInject : function(injectText){
		let text;
		if(this.isText())  text = this.props.brew.text;
		if(this.isStyle()) text = this.props.brew.style ?? DEFAULT_STYLE_TEXT;

		const lines = text.split('\n');
		const cursorPos = this.refs.codeEditor.getCursorPosition();
		lines[cursorPos.line] = splice(lines[cursorPos.line], cursorPos.ch, injectText);

		const injectLines = injectText.split('\n');
		this.refs.codeEditor.setCursorPosition(cursorPos.line + injectLines.length, cursorPos.ch  + injectLines[injectLines.length - 1].length);

		if(this.isText())  this.props.onTextChange(lines.join('\n'));
		if(this.isStyle()) this.props.onStyleChange(lines.join('\n'));
	},

	handleViewChange : function(newView){
		this.setState({
			view : newView
		}, this.updateEditorSize);	//TODO: not sure if updateeditorsize needed
	},

	getCurrentPage : function(){
		const lines = this.props.brew.text.split('\n').slice(0, this.cursorPosition.line + 1);
		return _.reduce(lines, (r, line)=>{
			if(line.indexOf('\\page') !== -1) r++;
			return r;
		}, 1);
	},

	highlightCustomMarkdown : function(){
		if(!this.refs.codeEditor) return;
		if(this.state.view === 'text')  {
			const codeMirror = this.refs.codeEditor.codeMirror;

			codeMirror.operation(()=>{ // Batch CodeMirror styling
				//reset custom text styles
				const customHighlights = codeMirror.getAllMarks().filter((mark)=>!mark.__isFold); //Don't undo code folding
				for (let i=customHighlights.length - 1;i>=0;i--) customHighlights[i].clear();

				let editorPageCount = 2; // start page count from page 2

				_.forEach(this.props.brew.text.split('\n'), (line, lineNumber)=>{

					//reset custom line styles
					codeMirror.removeLineClass(lineNumber, 'background', 'pageLine');
					codeMirror.removeLineClass(lineNumber, 'text');

					// Styling for \page breaks
					if((this.props.renderer == 'legacy' && line.includes('\\page')) ||
				     (this.props.renderer == 'V3'     && line.match(/^\\page$/))) {

						// add back the original class 'background' but also add the new class '.pageline'
						codeMirror.addLineClass(lineNumber, 'background', 'pageLine');
						const pageCountElement = Object.assign(document.createElement('span'), {
							className   : 'editor-page-count',
							textContent : editorPageCount
						});
						codeMirror.setBookmark({ line: lineNumber, ch: line.length }, pageCountElement);

						editorPageCount += 1;
					};

					// New Codemirror styling for V3 renderer
					if(this.props.renderer == 'V3') {
						if(line.match(/^\\column$/)){
							codeMirror.addLineClass(lineNumber, 'text', 'columnSplit');
						}

						// Highlight inline spans {{content}}
						if(line.includes('{{') && line.includes('}}')){
							const regex = /{{(?::(?:"[\w,\-()#%. ]*"|[\w\,\-()#%.]*)|[^"'{}\s])*\s*|}}/g;
							let match;
							let blockCount = 0;
							while ((match = regex.exec(line)) != null) {
								if(match[0].startsWith('{')) {
									blockCount += 1;
								} else {
									blockCount -= 1;
								}
								if(blockCount < 0) {
									blockCount = 0;
									continue;
								}
								codeMirror.markText({ line: lineNumber, ch: match.index }, { line: lineNumber, ch: match.index + match[0].length }, { className: 'inline-block' });
							}
						} else if(line.trimLeft().startsWith('{{') || line.trimLeft().startsWith('}}')){
							// Highlight block divs {{\n Content \n}}
							let endCh = line.length+1;

							const match = line.match(/^ *{{(?::(?:"[\w,\-()#%. ]*"|[\w\,\-()#%.]*)|[^"'{}\s])* *$|^ *}}$/);
							if(match)
								endCh = match.index+match[0].length;
							codeMirror.markText({ line: lineNumber, ch: 0 }, { line: lineNumber, ch: endCh }, { className: 'block' });
						}
					}
				});
			});
		}
	},

	brewJump : function(){
		const currentPage = this.getCurrentPage();
		window.location.hash = `p${currentPage}`;
	},

	//Called when there are changes to the editor's dimensions
	update : function(){
		this.refs.codeEditor?.updateSize();
	},

	//Called by CodeEditor after document switch, so Snippetbar can refresh UndoHistory
	rerenderParent : function (){
		this.forceUpdate();
	},

	renderEditor : function(){
		if(this.isText()){
			return <>
				<CodeEditor key='codeEditor'
					ref='codeEditor'
					language='gfm'
					view={this.state.view}
					value={this.props.brew.text}
					onChange={this.props.onTextChange}
					rerenderParent={this.rerenderParent} />
			</>;
		}
		if(this.isStyle()){
			return <>
				<CodeEditor key='codeEditor'
					ref='codeEditor'
					language='css'
					view={this.state.view}
					value={this.props.brew.style ?? DEFAULT_STYLE_TEXT}
					onChange={this.props.onStyleChange}
					enableFolding={false}
					rerenderParent={this.rerenderParent} />
			</>;
		}
		if(this.isMeta()){
			return <>
				<CodeEditor key='codeEditor'
					view={this.state.view}
					style={{ display: 'none' }}
					rerenderParent={this.rerenderParent} />
				<MetadataEditor
					metadata={this.props.brew}
					onChange={this.props.onMetaChange} />
			</>;
		}
	},

	redo : function(){
		return this.refs.codeEditor?.redo();
	},

	historySize : function(){
		return this.refs.codeEditor?.historySize();
	},

	undo : function(){
		return this.refs.codeEditor?.undo();
	},

	render : function(){
		return (
			<div className='editor' ref='main'>
				<SnippetBar
					brew={this.props.brew}
					view={this.state.view}
					onViewChange={this.handleViewChange}
					onInject={this.handleInject}
					showEditButtons={this.props.showEditButtons}
					renderer={this.props.renderer}
					undo={this.undo}
					redo={this.redo}
					historySize={this.historySize()} />

				{this.renderEditor()}
			</div>
		);
	}
});

module.exports = Editor;