import R from 'ramda'
import React from 'react'
import {anyNull, val} from './traverse-common-functions'
import {Node, Leaf} from './traverse-common-jsx'
import {makeJsx, evaluateNode, rewriteNode, evaluateArray, evaluateObject, parseObject, collectNodeMissing} from './evaluation'

let constantNode = constant => ({nodeValue: constant})

let transformPercentage = s =>
	R.contains('%')(s) ?
		+s.replace('%', '') / 100
	: +s

export let decompose = (recurse, k, v) => {
	let
		subProps = R.dissoc('composantes')(v),
		filter = val(recurse("sys . filter")),
		isRelevant = c => !filter || !c.attributs || c.attributs['dû par'] == filter,
		explanation = v.composantes.filter(isRelevant).map(c =>
			({
				... recurse(
					R.objOf(k,
						{
							... subProps,
							... R.dissoc('attributs')(c)
						})
				),
				composante: c.nom ? {nom: c.nom} : c.attributs
			})
		)

	let jsx = (nodeValue, explanation) =>
		<Node
			classes="mecanism composantes"
			name="composantes"
			value={nodeValue}
			child={
				<ul>
					{ explanation.map((c, i) =>
						[<li className="composante" key={JSON.stringify(c.composante)}>
							<ul className="composanteAttributes">
								{R.toPairs(c.composante).map(([k,v]) =>
									<li>
										<span>{k}: </span>
										<span>{v}</span>
									</li>
								)}
							</ul>
							<div className="content">
								{makeJsx(c)}
							</div>
						</li>,
						i < (explanation.length - 1) && <li className="composantesSymbol"><i className="fa fa-plus-circle" aria-hidden="true"></i></li>
						])
					}
				</ul>
			}
		/>

	return {
		explanation,
		jsx,
		evaluate: evaluateArray(R.add,0),
		category: 'mecanism',
		name: 'composantes',
		type: 'numeric'
	}
}

export let mecanismOneOf = (recurse, k, v) => {
	if (!R.is(Array,v)) throw 'should be array'

	let explanation = R.map(recurse, v)

	let jsx = (nodeValue, explanation) =>
		<Node
			classes="mecanism conditions list"
			name='une de ces conditions'
			value={nodeValue}
			child={
				<ul>
					{explanation.map(item => <li key={item.name || item.text}>{makeJsx(item)}</li>)}
				</ul>
			}
		/>

	return {
		evaluate: evaluateArray(R.or,false),
		jsx,
		explanation,
		category: 'mecanism',
		name: 'une de ces conditions',
		type: 'boolean'
	}
}

export let mecanismAllOf = (recurse, k,v) => {
	if (!R.is(Array,v)) throw 'should be array'

	let explanation = R.map(recurse, v)

	let jsx = (nodeValue, explanation) =>
		<Node
			classes="mecanism conditions list"
			name='toutes ces conditions'
			value={nodeValue}
			child={
				<ul>
					{explanation.map(item => <li key={item.name || item.text}>{makeJsx(item)}</li>)}
				</ul>
			}
		/>

	return {
		evaluate: evaluateArray(R.and,true),
		jsx,
		explanation,
		category: 'mecanism',
		name: 'toutes ces conditions',
		type: 'boolean'
	}
}

export let mecanismNumericalLogic = (recurse, k,v) => {
	if (R.is(String,v)) {
		// This seems an undue limitation
		return mecanismPercentage(recurse,k,v)
	}

	if (!R.is(Object,v) || R.keys(v).length == 0) {
		throw 'Le mécanisme "logique numérique" et ses sous-logiques doivent contenir au moins une proposition'
	}

	let parseCondition = ([condition, consequence]) => {
		let
			conditionNode = recurse(condition), // can be a 'comparison', a 'variable', TODO a 'negation'
			consequenceNode = mecanismNumericalLogic(recurse, condition, consequence)

			let collectMissing = node =>
				R.concat(collectNodeMissing(conditionNode),collectNodeMissing(consequenceNode))

			let evaluate = (situationGate, parsedRules, node) => ({
					...node,
					nodeValue: evaluateNode(situationGate, parsedRules, consequenceNode).nodeValue,
					condValue: evaluateNode(situationGate, parsedRules, conditionNode).nodeValue
				})

		let jsx = (nodeValue, {condition, consequence}) =>
			<div className="condition">
					{makeJsx(condition)}
					<div>
						{makeJsx(consequence)}
					</div>
				</div>

		return {
				evaluate,
				jsx,
				collectMissing,
				explanation: {condition: conditionNode, consequence: consequenceNode},
				category: 'condition',
				text: condition,
				condition: conditionNode,
				type: 'boolean',
			}
	}

	let evaluateTerms = (situationGate, parsedRules, node) => {
		let evaluateOne = child => evaluateNode(situationGate, parsedRules, child),
		    explanation = R.map(evaluateOne, node.explanation),
			choice = R.find(node => node.condValue, explanation),
			nodeValue = choice ? choice.nodeValue : null

		let collectMissing = node => R.chain(collectNodeMissing,node.explanation)
		return rewriteNode(node,nodeValue,explanation,collectMissing)
	}

	let terms = R.toPairs(v)

	let explanation = R.map(parseCondition,terms)

	let jsx = (nodeValue, explanation) =>
		<Node
			classes="mecanism numericalLogic list"
			name="logique numérique"
			value={nodeValue}
			child={
				<ul>
					{explanation.map(item => <li key={item.name || item.text}>{makeJsx(item)}</li>)}
				</ul>
			}
		/>

	return {
		evaluate: evaluateTerms,
		jsx,
		explanation,
		category: 'mecanism',
		name: "logique numérique",
		type: 'boolean || numeric' // lol !
	}
}

export let mecanismPercentage = (recurse,k,v) => {
	let reg = /^(\d+(\.\d+)?)\%$/
	if (R.test(reg)(v))
		return {
			type: 'numeric',
			category: 'percentage',
			nodeValue: R.match(reg)(v)[1]/100,
			explanation: null,
			jsx:
				<span className="percentage" >
					<span className="name">{v}</span>
				</span>
		}
	else {
		let node = recurse(v)
		let evaluate = (situation, parsedRules, node) => evaluateNode(situation, parsedRules, node.explanation)
		let jsx = (nodeValue,explanation) => makeJsx(explanation)
		return {
			evaluate,
			jsx,
			type: 'numeric',
			category: 'percentage',
			explanation: node
		}
	}
}

export let mecanismSum = (recurse,k,v) => {
	let explanation = v.map(recurse)

	let evaluate = evaluateArray(R.add,0)

	let jsx = (nodeValue, explanation) =>
		<Node
			classes="mecanism somme"
			name="somme"
			value={nodeValue}
			child={
				<ul>
					{explanation.map(v => <li key={v.name || v.text}>{makeJsx(v)}</li>)}
				</ul>
			}
		/>

	return {
		evaluate,
		jsx,
		explanation,
		category: 'mecanism',
		name: 'somme',
		type: 'numeric'
	}
}

export let mecanismProduct = (recurse,k,v) => {
	if (v.composantes) { //mécanisme de composantes. Voir known-mecanisms.md/composantes
		return decompose(recurse,k,v)
	}

	// Preprocessing step to parse percentages
	let wrap = x => ({taux: x}),
		value = R.evolve({taux:wrap},v)

	let objectShape = {
		assiette:false,
		taux:constantNode(1),
		facteur:constantNode(1),
		plafond:constantNode(Infinity)
	}
	let effect = ({assiette,taux,facteur,plafond}) => {
		let mult = (base, rate, facteur, plafond) => Math.min(base, plafond) * rate * facteur
		return (val(taux) === 0 || val(taux) === false || val(assiette) === 0 || val(facteur) === 0) ?
			0
		: anyNull([taux, assiette, facteur, plafond]) ?
				null
			: mult(val(assiette), val(taux), val(facteur), val(plafond))
	}

	let explanation = parseObject(recurse,objectShape,value),
		evaluate = evaluateObject(objectShape,effect)

	let jsx = (nodeValue, explanation) =>
		<Node
			classes="mecanism multiplication"
			name="multiplication"
			value={nodeValue}
			child={
				<ul className="properties">
					<li key="assiette">
						<span className="key">assiette: </span>
						<span className="value">{makeJsx(explanation.assiette)}</span>
					</li>
					{explanation.taux.nodeValue != 1 &&
					<li key="taux">
						<span className="key">taux: </span>
						<span className="value">{makeJsx(explanation.taux)}</span>
					</li>}
					{explanation.facteur.nodeValue != 1 &&
					<li key="facteur">
						<span className="key">facteur: </span>
						<span className="value">{makeJsx(explanation.facteur)}</span>
					</li>}
					{explanation.plafond.nodeValue != Infinity &&
					<li key="plafond">
						<span className="key">plafond: </span>
						<span className="value">{makeJsx(explanation.plafond)}</span>
					</li>}
				</ul>
			}
		/>

	return {
		evaluate,
		jsx,
		explanation,
		category: 'mecanism',
		name: 'multiplication',
		type: 'numeric'
	}
}

export let mecanismScale = (recurse,k,v) => {
	// Sous entendu : barème en taux marginaux.
	// A étendre (avec une propriété type ?) quand les règles en contiendront d'autres.
	if (v.composantes) { //mécanisme de composantes. Voir known-mecanisms.md/composantes
		return decompose(recurse,k,v)

	}

	if (v['multiplicateur des tranches'] == null)
		throw "un barème nécessite pour l'instant une propriété 'multiplicateur des tranches'"

	/* on réécrit en plus bas niveau les tranches :
	`en-dessous de: 1`
	devient
	```
	de: 0
	à: 1
	```
	*/
	let tranches = v['tranches'].map(t =>
			R.has('en-dessous de')(t) ? {de: 0, 'à': t['en-dessous de'], taux: t.taux}
			: R.has('au-dessus de')(t) ? {de: t['au-dessus de'], 'à': Infinity, taux: t.taux}
				: t)

	let aliased = {
		...v,
		multiplicateur: v['multiplicateur des tranches']
	}

	let objectShape = {
		assiette:false,
		multiplicateur:false
	}

	let effect = ({assiette, multiplicateur, tranches}) => {
		//TODO appliquer retreat() à de, à, taux pour qu'ils puissent contenir des calculs ou pour les cas où toutes les tranches n'ont pas un multiplicateur commun (ex. plafond sécurité sociale). Il faudra alors vérifier leur nullité comme ça :
		/*
			nulled = assiette.nodeValue == null || R.any(
				R.pipe(
					R.values, R.map(val), R.any(R.equals(null))
				)
			)(tranches),
		*/
		// nulled = anyNull([assiette, multiplicateur]),
		let nulled = val(assiette) == null || val(multiplicateur) == null

		return nulled ?
				null
			: tranches.reduce((memo, {de: min, 'à': max, taux}) =>
				( val(assiette) < ( min * val(multiplicateur) ) )
					? memo + 0
					:	memo
						+ ( Math.min(val(assiette), max * val(multiplicateur)) - (min * val(multiplicateur)) )
						* transformPercentage(taux)
			, 0)
		}

	let explanation = {
				...parseObject(recurse,objectShape,aliased),
				tranches
			},
		evaluate = evaluateObject(objectShape,effect)

	let jsx = (nodeValue, explanation) =>
		<Node
			classes="mecanism barème"
			name="barème"
			value={nodeValue}
			child={
				<ul className="properties">
					<li key="assiette">
						<span className="key">assiette: </span>
						<span className="value">{makeJsx(explanation.assiette)}</span>
					</li>
					<li key="multiplicateur">
						<span className="key">multiplicateur des tranches: </span>
						<span className="value">{makeJsx(explanation.multiplicateur)}</span>
					</li>
					<table className="tranches">
						<thead>
							<tr>
								<th>Tranches de l'assiette</th>
								<th>Taux</th>
							</tr>
							{explanation.tranches.map(({'en-dessous de': maxOnly, 'au-dessus de': minOnly, de: min, 'à': max, taux}) =>
								<tr key={min || minOnly || 0}>
									<td>
										{	maxOnly ? 'En dessous de ' + maxOnly
											: minOnly ? 'Au dessus de ' + minOnly
												: `De ${min} à ${max}` }
									</td>
									<td> {taux} </td>
								</tr>
							)}
						</thead>
					</table>
				</ul>
			}
		/>

	return {
		evaluate,
		jsx,
		explanation,
		category: 'mecanism',
		name: 'barème',
		barème: 'en taux marginaux',
		type: 'numeric'
	}
}

export let mecanismMax = (recurse,k,v) => {
	let explanation = v.map(recurse)

	let evaluate = evaluateArray(R.max,Number.NEGATIVE_INFINITY)

	let jsx = (nodeValue, explanation) =>
		<Node
			classes="mecanism list maximum"
			name="le maximum de"
			value={nodeValue}
			child={
				<ul>
				{explanation.map((item, i) =>
					<li key={i}>
						<div className="description">{v[i].description}</div>
						{makeJsx(item)}
					</li>
				)}
				</ul>
			}
		/>

	return {
		evaluate,
		jsx,
		explanation,
		type: 'numeric',
		category: 'mecanism',
		name: 'le maximum de'
	}
}

export let mecanismComplement = (recurse,k,v) => {
	if (v.composantes) { //mécanisme de composantes. Voir known-mecanisms.md/composantes
		return decompose(recurse,k,v)
	}

	let objectShape = {cible:false,montant:false}
	let effect = ({cible,montant}) => {
		let nulled = val(cible) == null
		return nulled ? null : R.subtract(val(montant), R.min(val(cible), val(montant)))
	}
	let explanation = parseObject(recurse,objectShape,v)

	return {
		evaluate: evaluateObject(objectShape,effect),
		explanation,
		type: 'numeric',
		category: 'mecanism',
		name: 'complément pour atteindre',
		jsx: <Node
			classes="mecanism list complement"
			name="complément pour atteindre"
			child={
				<ul className="properties">
					<li key="cible">
						<span className="key">montant calculé: </span>
						<span className="value">{makeJsx(explanation.cible)}</span>
					</li>
					<li key="mini">
						<span className="key">montant à atteindre: </span>
						<span className="value">{makeJsx(explanation.montant)}</span>
					</li>
				</ul>
			}
		/>
	}
}

export let mecanismError = (recurse,k,v) => {
	throw "Le mécanisme est inconnu !"
}