import {
	flatten,
	mergeAll,
	pluck,
	groupBy,
	toPairs,
	sort,
	map,
	length,
	descend,
	head,
	unless,
	is,
	prop,
	pick,
	path,
	reject,
	identity
} from 'ramda'
import React from 'react'
import Question from 'Components/conversation/Question'
import Input from 'Components/conversation/Input'
import Select from 'Components/conversation/select/Select'
import SelectAtmp from 'Components/conversation/select/SelectTauxRisque'
import formValueTypes from 'Components/conversation/formValueTypes'
import InversionInput from '../components/conversation/InversionInput'

import {
	findRuleByDottedName,
	disambiguateRuleReference,
	queryRule
} from './rules'

/*
	COLLECTE DES VARIABLES MANQUANTES
	*********************************
	on collecte les variables manquantes : celles qui sont nécessaires pour
	remplir les objectifs de la simulation (calculer des cotisations) mais qui n'ont pas
	encore été renseignées

	TODO perf : peut-on le faire en même temps que l'on traverse l'AST ?
	Oui sûrement, cette liste se complète en remontant l'arbre. En fait, on le fait déjà pour nodeValue,
	et quand nodeValue vaut null, c'est qu'il y a des missingVariables ! Il suffit donc de remplacer les
	null par un tableau, et d'ailleurs utiliser des fonction d'aide pour mutualiser ces tests.

	missingVariables: {variable: [objectives]}
 */

export let collectMissingVariables = targets => mergeAll(pluck('missingVariables', targets))

export let getNextSteps = (situationGate, analysis) => {
	let impact = ([, count]) => count

	let missingVariables = collectMissingVariables(analysis.targets),
		pairs = toPairs(missingVariables),
		sortedPairs = sort(descend(impact), pairs)
	return map(head, sortedPairs)
}

let isVariant = rule => queryRule(rule.raw)('formule . une possibilité')

let buildVariantTree = (allRules, path) => {
	let rec = path => {
		let node = findRuleByDottedName(allRules, path),
			variant = isVariant(node),
			variants = variant && unless(is(Array), prop('possibilités'))(variant),
			shouldBeExpanded = variant && true, //variants.find( v => relevantPaths.find(rp => contains(path + ' . ' + v)(rp) )),
			canGiveUp = variant && !variant['choix obligatoire']

		return Object.assign(
			node,
			shouldBeExpanded
				? {
						canGiveUp,
						children: variants.map(v => rec(path + ' . ' + v))
				  }
				: null
		)
	}
	return rec(path)
}

let buildPossibleInversion = (rule, rules, targetNames) => {
	let query = queryRule(rule),
		inversion = query('formule . inversion')

	if (!inversion) return null
	let inversionObjects = query('formule . inversion . avec').map(i =>
			findRuleByDottedName(rules, disambiguateRuleReference(rules, rule, i))
		),
		inversions = reject(({ name }) => targetNames.includes(name))(
			[rule].concat(inversionObjects)
		)

	return {
		inversions,
		question: query('formule . inversion . question')
	}
}

// This function takes the unknown rule and finds which React component should be displayed to get a user input through successive if statements
// That's not great, but we won't invest more time until we have more diverse input components and a better type system.
export let getInputComponent = ({ unfolded }) => (
	rules,
	targetNames
) => dottedName => {
	let rule = findRuleByDottedName(rules, dottedName)

	let commonProps = {
		key: dottedName,
		unfolded,
		fieldName: dottedName,
		...pick(['dottedName', 'title', 'question', 'defaultValue'], rule)
	}

	if (isVariant(rule))
		return (
			<Question
				{...{
					...commonProps,
					choices: buildVariantTree(rules, dottedName)
				}}
			/>
		)

	if (rule.format == null)
		return (
			<Question
				{...{
					...commonProps,
					choices: [
						{ value: 'non', label: 'Non' },
						{ value: 'oui', label: 'Oui' }
					]
				}}
			/>
		)

	if (rule.suggestions == 'atmp-2017')
		return (
			<SelectAtmp
				{...{
					...commonProps,
					valueType: formValueTypes[rule.format],
					suggestions: rule.suggestions
				}}
			/>
		)

	if (typeof rule.suggestions == 'string')
		return (
			<Select
				{...{
					...commonProps,
					valueType: formValueTypes[rule.format],
					suggestions: rule.suggestions
				}}
			/>
		)

	// Now the numeric input case

	// Check for inversions
	let inversion = buildPossibleInversion(rule, rules, targetNames)

	/* In the case of an inversion, display a RadioInput component.
	On click on one of the radios, display the corresponding input.
	If only one inversion is possible, don't show the radio but show the documentation icon.
	Else just display the Input component.
	*/

	if (inversion)
		return (
			<InversionInput
				{...{
					...commonProps,
					valueType: formValueTypes[rule.format],
					suggestions: rule.suggestions,
					inversion
				}}
			/>
		)

	return (
		<Input
			{...{
				...commonProps,
				valueType: formValueTypes[rule.format],
				suggestions: rule.suggestions
			}}
		/>
	)
}