import { parseUnit } from "Engine/units";
import {
  assoc,
  chain,
  dropLast,
  find,
  fromPairs,
  has,
  is,
  isNil,
  join,
  last,
  map,
  path,
  pipe,
  propEq,
  props,
  range,
  reduce,
  reduced,
  reject,
  split,
  take,
  toPairs,
  trim,
  when
} from "ramda";
import rawRules from "Règles/base.yaml";
import translations from "Règles/externalized.yaml";
// TODO - should be in UI, not engine
import { capitalise0, coerceArray } from "../utils";
import possibleVariableTypes from "./possibleVariableTypes.yaml";

/***********************************
Functions working on one rule */

export let enrichRule = rule => {
  try {
    let unit = rule.unité && parseUnit(rule.unité);
    return {
      ...rule,
      type: possibleVariableTypes.find(t => has(t, rule) || rule.type === t),
      name: rule["nom"],
      title: capitalise0(rule["titre"] || rule["nom"]),
      ns: rule["espace"],
      dottedName: buildDottedName(rule),
      subquestionMarkdown: rule["sous-question"],
      defaultValue: rule["par défaut"],
      examples: rule["exemples"],
      icons: rule["icônes"],
      summary: rule["résumé"],
      unit
    };
  } catch (e) {
    console.log(e);
    throw new Error("Problem enriching " + JSON.stringify(rule));
  }
};

export let buildDottedName = rule =>
  rule["espace"] ? [rule["espace"], rule["nom"]].join(" . ") : rule["nom"];

// les variables dans les tests peuvent être exprimées relativement à l'espace de nom de la règle,
// comme dans sa formule
export let disambiguateExampleSituation = (rules, rule) =>
  pipe(
    toPairs,
    map(([k, v]) => [disambiguateRuleReference(rules, rule, k), v]),
    fromPairs
  );

export let hasKnownRuleType = rule => rule && enrichRule(rule).type;

export let splitName = split(" . "),
  joinName = join(" . ");

export let parentName = pipe(
  splitName,
  dropLast(1),
  joinName
);
export let nameLeaf = pipe(
  splitName,
  last
);

export let encodeRuleName = name =>
  encodeURI(name.replace(/\s\.\s/g, "/").replace(/\s/g, "-"));
export let decodeRuleName = name =>
  decodeURI(name.replace(/\//g, " . ").replace(/-/g, " "));

export let ruleParents = dottedName => {
  let fragments = splitName(dottedName); // dottedName ex. [CDD . événements . rupture]
  return range(1, fragments.length)
    .map(nbEl => take(nbEl)(fragments))
    .reverse(); //  -> [ [CDD . événements . rupture], [CDD . événements], [CDD] ]
};
/* Les variables peuvent être exprimées dans la formule d'une règle relativement à son propre espace de nom, pour une plus grande lisibilité. Cette fonction résoud cette ambiguité.
 */
export let disambiguateRuleReference = (
  allRules,
  { dottedName, name },
  partialName
) => {
  let pathPossibilities = [
      [], // the top level namespace
      ...ruleParents(dottedName), // the parents namespace
      splitName(dottedName) // the rule's own namespace
    ],
    found = reduce(
      (res, path) =>
        when(is(Object), reduced)(
          do {
            let dottedNameToCheck = [...path, partialName].join(" . ");
            findRuleByDottedName(allRules, dottedNameToCheck);
          }
        ),
      null,
      pathPossibilities
    );

  return (
    (found && found.dottedName) ||
    do {
      throw new Error(
        `OUUUUPS la référence '${partialName}' dans la règle '${name}' est introuvable dans la base`
      );
    }
  );
};

export let collectDefaults = pipe(
  map(props(["dottedName", "defaultValue"])),
  reject(([, v]) => v === undefined),
  fromPairs
);

/****************************************
 Méthodes de recherche d'une règle */

export let findRuleByName = (allRules, query) =>
  (Array.isArray(allRules) ? allRules : Object.values(allRules)).find(
    ({ name }) => name === query
  );

export let findRulesByName = (allRules, query) =>
  (Array.isArray(allRules) ? allRules : Object.values(allRules)).filter(
    ({ name }) => name === query
  );

export let findRuleByDottedName = (allRules, dottedName) =>
  Array.isArray(allRules)
    ? allRules.find(rule => rule.dottedName == dottedName)
    : allRules[dottedName];

export let findRule = (rules, nameOrDottedName) =>
  nameOrDottedName.includes(" . ")
    ? findRuleByDottedName(rules, nameOrDottedName)
    : findRuleByName(rules, nameOrDottedName);

export let findRuleByNamespace = (allRules, ns) =>
  allRules.filter(propEq("ns", ns));

/*********************************
 Autres */

export let queryRule = rule => query => path(query.split(" . "))(rule);

// Redux-form stores the form values as a nested object
// This helper makes a dottedName => value Map
export let nestedSituationToPathMap = situation => {
  if (situation == undefined) return {};
  let rec = (o, currentPath) =>
    typeof o === "object"
      ? chain(([k, v]) => rec(v, [...currentPath, trim(k)]), toPairs(o))
      : [[currentPath.join(" . "), o + ""]];

  return fromPairs(rec(situation, []));
};

/* Traduction */

export let translateAll = (translations, flatRules) => {
  let translationsOf = rule => translations[buildDottedName(rule)],
    translateProp = (lang, translation) => (rule, prop) => {
      let propTrans = translation[prop + "." + lang];
      if (prop === "suggestions" && propTrans)
        return assoc(
          "suggestions",
          pipe(
            toPairs,
            map(([key, translatedKey]) => [
              translatedKey,
              rule.suggestions[key]
            ]),
            fromPairs
          )(propTrans),
          rule
        );
      return propTrans ? assoc(prop, propTrans, rule) : rule;
    },
    translateRule = (lang, translations, props) => rule => {
      let ruleTrans = translationsOf(rule);
      return ruleTrans
        ? reduce(translateProp(lang, ruleTrans), rule, props)
        : rule;
    };

  let targets = [
    "titre",
    "description",
    "question",
    "sous-question",
    "résumé",
    "suggestions",
    "contrôles"
  ];

  return map(translateRule("en", translations, targets), flatRules);
};

// On enrichit la base de règles avec des propriétés dérivées de celles du YAML
export let rules = translateAll(translations, rawRules).map(rule =>
  enrichRule(rule)
);

export let rulesFr = rawRules.map(rule => enrichRule(rule));

export let findParentDependency = (rules, rule) => {
  // A parent dependency means that one of a rule's parents is not just a namespace holder, it is a boolean question. E.g. is it a fixed-term contract, yes / no
  // When it is resolved to false, then the whole branch under it is disactivated (non applicable)
  // It lets those children omit obvious and repetitive parent applicability tests
  let parentDependencies = ruleParents(rule.dottedName).map(joinName);
  return pipe(
    map(parent => findRuleByDottedName(rules, parent)),
    reject(isNil),
    find(
      //Find the first "calculable" parent
      ({ question, unit, formule }) => question && !unit && !formule //implicitly, the format is boolean
    )
  )(parentDependencies);
};

export let getRuleFromAnalysis = analysis => dottedName => {
  if (!analysis) {
    throw new Error("[getRuleFromAnalysis] The analysis can't be nil !");
  }
  let rule = coerceArray(analysis) // In some simulations, there are multiple "branches" : the analysis is run with e.g. 3 different input situations
    .map(
      analysis =>
        analysis.cache[dottedName]?.explanation || // the cache stores a reference to a variable, the variable is contained in the 'explanation' attribute
        analysis.targets.find(propEq("dottedName", dottedName))
    )
    .filter(Boolean)[0];

  if (!rule) {
    throw new Error(
      `[getRuleFromAnalysis] Unable to find the rule ${dottedName}`
    );
  }

  return rule;
};