"use strict";

function makeFieldset() {
	return document.createElement('fieldset');
}

function makeLegend(...legend) {
	let ret = document.createElement('legend');
	ret.append(...legend);
	return ret;
}

function makeButton(label, onClick) {
	let ret = document.createElement('button');
	ret.setAttribute('type', 'button');
	ret.append(label);
	ret.addEventListener('click', onClick);
	return ret;
}

function makeText(text) {
	return document.createTextNode(text);
}

function makeInput(id, attrs) {
	let ret = document.createElement('input');
	ret.setAttribute('id', id);
	for (const [attr, value] of Object.entries(attrs)) {
		ret.setAttribute(attr, value);
	}
	return ret;
}
function makeLabel(label, forId) {
	let ret = document.createElement('label');
	ret.setAttribute('for', forId);
	ret.innerHTML = label;
	return ret;
}

class L3Section {
	constructor(legend, presetname, ...inputs) {
		this.legend = legend;
		this.presetname = presetname;
		this.inputs = inputs;
	}
	node() {
		let fieldset = makeFieldset();
		let legend = this.legend;
		if (this.presetname instanceof HTMLElement) {
			legend = this.presetname;
		}
		fieldset.append(makeLegend(legend));
		let sep = undefined;
		for (const input of this.inputs) {
			fieldset.append(input.node());
		}
		return fieldset;
	}
	render() {
		const options = this.inputs
			.flatMap(input => input.option())
			.filter(option => !!option);

		if (options.length == 0) {
			return undefined;
		}

		var compiledopts = new Map();
		for (const option of options) {
			let c = compiledopts.get(option.optionName) ?? [];
			c.push(option.value);
			compiledopts.set(option.optionName, c);
		}

		let optstrs = [];
		for (const [opt, values] of compiledopts) {
			if (values.length == 1) {
				optstrs.push(`option ${opt} '${values[0]}'`);
			} else {
				for (const value of values) {
					optstrs.push(`list ${opt} '${value}'`);
				}
			}
		}
		let sectionname = "";
		if (typeof this.presetname === 'string') {
			sectionname = ` '${this.presetname}'`;
		} else if (this.presetname instanceof HTMLElement
			&& this.presetname.tagName === 'INPUT'
			&& this.presetname.value) {
			sectionname = ` '${this.presetname.value}'`;
		}
		return `config ${this.legend}${sectionname}\n\t` + optstrs.join('\n\t');
	}
}

class L3MultiSection {
	constructor(legend, template) {
		this.legend = legend;
		this.template = template;
		this.sections = [];
		this.nsections = 0;
	}
	node() {
		let fieldset = makeFieldset();
		fieldset.append(
			makeLegend(
				makeButton(`+ ${this.legend}`, () => fieldset.appendChild(this.#makeSection())),
			)
		);
		return fieldset;
	}
	#makeSection() {
		const idsuffix = `-${this.nsections++}`;
		let newsection = this.template(idsuffix);
		this.sections.push(newsection);
		let nodes = newsection.node();

		let del = makeButton('Remove', () => this.#removeSection(newsection, nodes));
		del.classList.add('del');

		nodes.append(del);
		return nodes;
	}
	#removeSection(del, nodes) {
		this.sections = this.sections.filter(section => section != del);
		nodes.remove();
	}
	render() {
		return this.sections.map(section => section.render()).filter(section => !!section)
	}
}

class L3Input {
	constructor(label, id, optionName, attrs, datalist) {
		this.label = label;
		this.id = id;
		this.optionName = optionName;
		this.attrs = attrs;
		this.datalist = datalist
		this.input = undefined;
	}
	node() {
		let div = document.createElement('div')
		if (this.label) {
			div.appendChild(makeLabel(this.label, this.id));
		}

		this.input = makeInput(this.id, this.attrs);
		div.appendChild(this.input);

		if (this.datalist) {
			let datalist = document.createElement('datalist');
			let datalistid = this.id + '-datalist';
			datalist.setAttribute('id', datalistid);
			this.input.setAttribute('list', datalistid);

			for (const value of this.datalist) {
				let option = document.createElement('option');
				option.setAttribute('value', value);
				datalist.append(option);
			}

			div.appendChild(datalist);
		}

		return div;

	}
	option() {
		switch (this.input.type) {
			case 'radio':
			case 'checkbox':
				if (!this.input.checked || this.input.value == 'undefined') return undefined;
				break;
			default:
				if (!this.input.value) return undefined;
				break;
		}

		const ret = {
			optionName: this.optionName,
			value: this.input.value,
		};

		return ret;
	}
}

class L3Select {
	constructor(label, id, optionName, attrs, ...optionList) {
		this.label = label;
		this.id = id;
		this.optionName = optionName;
		this.attrs = attrs;
		this.optionList = optionList;
		this.input = undefined;
	}
	node() {
		let div = document.createElement('div')
		if (this.label) {
			div.appendChild(makeLabel(this.label, this.id));
		}

		this.input = document.createElement('select');
		this.input.setAttribute('id', this.id);
		for (const [attr, value] of Object.entries(this.attrs)) {
			this.input.setAttribute(attr, value);
		}
		div.appendChild(this.input);

		for (const [optgrouplabel, options] of this.optionList) {
			let target = this.input;
			if (optgrouplabel != '') {
				target = document.createElement('optgroup');
				target.setAttribute('label', optgrouplabel);
				this.input.appendChild(target);
			}
			for (const [label, value] of options) {
				let option = document.createElement('option');
				option.setAttribute('value', value);
				option.appendChild(makeText(label));
				target.appendChild(option);
			}
		}

		return div;

	}
	option() {
		if (this.input.value == 'undefined') { return undefined; }

		const ret = {
			optionName: this.optionName,
			value: this.input.value,
		};

		return ret;
	}
}

class L3MultiInput {
	constructor(label, template) {
		this.label = label;
		this.template = template;
		this.inputs = [];
		this.ninputs = 0;
	}
	node() {
		let fieldset = makeFieldset();
		fieldset.append(
			makeLegend(
				makeButton(`+ ${this.label}`, () => fieldset.append(this.#makeInput())),
			)
		);
		return fieldset;
	}
	#makeInput() {
		const idsuffix = `-${this.ninputs++}`;
		let newinput = this.template(idsuffix);
		this.inputs.push(newinput);
		let div = newinput.node();
		let delbutton = document.createElement('button');
		delbutton.setAttribute('type', 'button');
		delbutton.classList.add('del');
		delbutton.innerHTML = '-';
		delbutton.addEventListener('click', () => this.#removeInput(newinput, div));
		div.prepend(delbutton);
		return div;
	}
	#removeInput(del, div) {
		this.inputs = this.inputs.filter(input => input != del);
		div.remove();
	}
	option() {
		return this.inputs.map(input => input.option());
	}
}

class L3Config {
	constructor() {
		this.sections = [];
	}
	addSection(section) {
		this.sections.push(section)
	}
	handleUpdate() {
		renderConfig(this.sections.flatMap(section => section.render()).filter(section => !!section));
	}
	node() {
		return this.sections.map(section => section.node())
	}
}

function initForm() {
	let l3configinput = document.getElementById('l3configinput');
	let form = document.createElement('form');
	l3configinput.appendChild(form);

	const label5ghz = (chan) => [`${chan} (${5000+chan*5}MHz)`, chan.toString()]
	const label2ghz = (chan) => [`${chan} (${2407+chan*5}MHz)`, chan.toString()]
	const UNII1Channels = [36, 40, 44, 48].map(label5ghz);
	const UNII2Channels = [52, 56, 60, 64].map(label5ghz);
	const UNII2EChannels = [100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140].map(label5ghz);
	const Channels5GHz = [...UNII1Channels, ...UNII2Channels, ...UNII2EChannels];
	const Channels2GHz = Array(13).fill().map((_, chan) => [`${chan+1} (${2412 + chan*5}MHz)`, (chan+1).toString()]);
	const Channels2GHzOFDM = [1,5,9,13].map(label2ghz);
	const Channels2GHzDSSS = [1,6,11].map(label2ghz);

	const l3cfg = new L3Config();
	l3cfg.addSection(new L3Section('gateway', 'meta',
		new L3Input('Router Name','gatewayName', 'name', {type: 'search', placeholder: 'Router Name'}),
		new L3MultiInput('Router IPv4 Address', function(idsuffix) {
			return new L3Input(undefined,'gatewayRouterIP4'+idsuffix, 'router_ip', {type: 'search', maxlength: 15, placeholder: 'Router IPv4 Address'});
		}),
		new L3MultiInput('Router IPv6 Address', function(idsuffix) {
			return new L3Input(undefined,'gatewayRouterIP6'+idsuffix, 'router_ip6', {type: 'text', maxlength: 39, placeholder: 'Router IPv6 Address'});
		}),
		new L3Input(undefined, 'gatewayConfigVersion', 'config_version', {type: 'hidden', value: 2, disabled: ''}),
	));
	l3cfg.addSection(new L3Section('dns', undefined,
		new L3Select('Preset','dnsAnycastSelect', 'server', {name: 'anycast'},
			['', [
				['Anycast DNS', 'fd43:5602:29bd:ffff:1:1:1:1'],
				['Anycast DNS64', 'fd43:5602:29bd:ffff:1:1:1:64'],
				['---', undefined],
			]],
		),
		new L3MultiInput('Custom DNS Server', function(idsuffix) {
			return new L3Input(undefined,'dnsOther'+idsuffix, 'server', {type: 'text', maxlength: 39, placeholder: 'Custom DNS Server'});
		}),
	));
	l3cfg.addSection(new L3Section('wan', undefined,
		new L3Input('Use VLAN','babelpeerVLAN', 'vlan', {type: 'number', min: 1, max: 4094}),
		new L3Input('Use Interface directly','babelpeerIFACE', 'iface', {type: 'text', placeholder: 'eth0, eth0.4, ...'}),
	));
	l3cfg.addSection(new L3Section('client', undefined,
		new L3Input('Use VLAN','clientVLAN', 'vlan', {type: 'number', min: 1, max: 4094}),
		new L3Input('Use Interface directly','clientIFACE', 'iface', {type: 'text', placeholder: 'eth0, eth0.4, ...'}),
		new L3MultiInput('Client IPv6 Subnet', function(idsuffix) {
			return new L3Input(undefined,'clientIP6Addr'+idsuffix, 'ip6addr', {type: 'text', maxlength: 39, placeholder: 'IPv6 CIDR, 2a0b:f4c0:XX:YYYY::/64, fd43:5602:29bd:XXXX::/64,...'});
		}),
		new L3MultiInput('Client IPv4 Subnet', function(idsuffix) {
			return new L3Input(undefined,'clientIPAddr'+idsuffix, 'ipaddr', {type: 'text', maxlength: 15, placeholder: 'IPv4 CIDR, 10.XX.YY.ZZ/24'});
		}),
		new L3Input('IPv4 SNAT','clientSNAT', 'snat', {type: 'checkbox', value: 1}),
		new L3Input('DHCP Start Address','clientDHCPStart', 'dhcp_start', {type: 'text', maxlength: 15, placeholder: 'IPv4 Address, 10.XX.YY.10'}),
		new L3Input('DHCP Number of Addresses','clientDHCPLimit', 'dhcp_limit', {type: 'number', min: 1, max: 65535}),
		new L3Input('Wifi ESSID','clientESSID', 'essid', {type: 'text'}),
		new L3Select('Wifi 2.4 GHz Channel','client2GHZ', 'chan2ghz', {name: 'chan2ghz'},
			['', [['---', undefined]]],
			['Non-Overlapping Channels (OFDM)', Channels2GHzOFDM],
			['Non-Overlapping Channels (DSSS)', Channels2GHzDSSS],
			['All Channels', Channels2GHz],
		),
		new L3Select('Wifi 5 GHz Channel','client5GHZ', 'chan5ghz', {name: 'chan5ghz'},
			['', [['---', undefined]]],
			['U-NII-1 Channels (Indoor)', UNII1Channels],
			['U-NII-2 Channels (Indoor + DFS)', UNII2Channels],
			['U-NII-2E Channels (Indoor + Outdoor + DFS)', UNII2EChannels],
		),
	));
	l3cfg.addSection(new L3MultiSection('VLAN', function(idsuffix) {
		return new L3Section('vlan', makeInput('vlanSectionName'+idsuffix, {type: 'number', min: 1, max: 4094, required: '', placeholder: '1..4094'}),
			new L3Input('Comment','vlanComment'+idsuffix, 'comment', {type: 'text'}, ['client', 'wan']),
			new L3Input('Ports','vlanPorts'+idsuffix, 'ports', {type: 'text', placeholder: 'eth0:*, eth1.4:u, ...'}),
		);
	}));
	l3cfg.addSection(new L3MultiSection('Direct Babel Peering', function(idsuffix) {
		return new L3Section('babelpeer', makeInput('babelpeerSectionName'+idsuffix, {type: 'text'}),
			new L3Input('Use VLAN','babelpeerVLAN'+idsuffix, 'vlan', {type: 'number', min: 1, max: 4094}),
			new L3Input('Use Interface directly','babelpeerIFACE'+idsuffix, 'iface', {type: 'text', placeholder: 'eth0, eth0.4, ...'}),
			new L3Select('Babel Interface Type','babelpeerType'+idsuffix, 'type', {name: 'type'},
				['', [
					['Default', undefined],
					['Wired', 'wired'],
					['Wireless', 'wireless'],
				]],
			),
			new L3Input('rxcost','babelpeerRXCost'+idsuffix, 'rxcost', {type: 'number', min: 96, max: 65535, placeholder: 'LAN: 96, Tunnel: 4096, ...'}),
		);
	}));
	l3cfg.addSection(new L3MultiSection('WireGuard Peering', function(idsuffix) {
		return new L3Section('wireguardpeer', makeInput('wireguardpeerSectionName'+idsuffix, {type: 'text'}),
			new L3Input('Endpoint Host', 'wireguardpeerEPHost'+idsuffix, 'endpoint_host', {type: 'text', required: ''}, ['peering.nue3.fff.community','ff1.zbau.f3netze.de','nsvm.f3netze.de','2a0b:f4c0:400::']),
			new L3Input('Endpoint Port','wireguardpeerEPPort'+idsuffix, 'endpoint_port', {type: 'number', required: '', min:1, max: 65535}),
			new L3Input('Persistent Keepalive','wireguardpeerPersistentKeepalive', 'persistent_keepalive', {type: 'number', min: 0, max: 65535, placeholder: '1 - 65535 Seconds...'}),
			new L3Input('Remote Public Key', 'wireguardpeerRemotePubKey'+idsuffix, 'remote_public_key', {type: 'text', minlength: 44, maxlength: 44, required: '', placeholder: 'base64 encoded public key'}),
			new L3Input('Local Private Key', 'wireguardpeerLocalPrivKey'+idsuffix, 'local_private_key', {type: 'text', minlength: 44, maxlength: 44, placeholder: 'base64 encoded private key'}),
			new L3Input('rxcost','wireguardpeerRXCost'+idsuffix, 'rxcost', {type: 'number', min: 96, max: 65535, value: 4096, placeholder: '4096'}),
			new L3Input('mtu','wireguardpeerMTU'+idsuffix, 'mtu', {type: 'number', min: 1280, max: 65535, value: 1412, placeholder: '1412'}),
		);
	}));

	form.addEventListener('input', () => l3cfg.handleUpdate());
	form.replaceChildren(...l3cfg.node())
	renderConfig(l3cfg.sections.flatMap(section => section.render()).filter(section => !!section));
}

function renderConfig(sections) {
	let l3configoutput = document.getElementById('l3configoutput');
	let l3configoutputpre = document.createElement('pre');
	let code = document.createElement('code');
	l3configoutputpre.appendChild(code);

	code.innerHTML += sections.join('\n\n');

	l3configoutput.replaceChildren(l3configoutputpre);
}

initForm();