/**
 * Experiment 25A — Evidence-Condition Scope Comparison.
 *
 * Determines whether a piece of evidence and a decision condition refer to
 * the same claim and timeframe before direction classification is applied.
 *
 * Returns one of:
 *   "direct_match"        — same subject, present state in both
 *   "partial_match"       — relevant but only addresses part of the condition
 *   "different_timeframe" — present evidence vs future feasibility (or vice versa)
 *   "unrelated"           — different subjects entirely
 *   "cannot_determine"    — missing or unclear input
 *
 * Uses four deterministic rules. No LLM calls, no scoring, no mutation.
 */

/* ── Shared concept groups (subset of evidence-direction.js categories) ── */

/* ── Normalisation ─────────────────────────────────────────── */

function normalise(value) {
  return String(value || "").toLowerCase();
}

/* ── Present-state detection (condition) ──────────────────── */

const FUTURE_FEASIBILITY_PHRASES = [
  "can be achieved", "can achieve", "would require", "will achieve",
  "could achieve", "able to achieve", "be achieved", "is achievable",
  "feasible", "worth the cost",
];

function isPresentState(text) {
  /* Default: anything without future-feasibility markers is present-state */
  return !isFutureFeasibility(text);
}

function isFutureFeasibility(text) {
  return FUTURE_FEASIBILITY_PHRASES.some((p) => text.includes(p));
}

/* ── Concept family matching ──────────────────────────────── */

/**
 * Each concept has two keyword lists:
 *   core — words that directly identify this concept (e.g. "demand", "compliance").
 *   related — words that typically co-occur with the concept in evidence text.
 * A category is "shared" when the condition contains a core word AND the evidence
 * contains either the same core word OR any related word from that concept family.
 */

const CONCEPT_FAMILIES = {
  demand: {
    core: ["demand", "need", "customer demand", "audience"],
    related: ["market exists", "valued at", "growing market", "interest", "market size", "growing"],
  },
  compliance: {
    core: ["compliance", "gdpr", "regulation", "data residency"],
    related: ["eu compliance", "achieve compliance", "supports gdpr", "meets regulation", "supports data residency", "support eu"],
  },
  value_cost: {
    core: ["cost", "investment", "viability", "financial viability"],
    related: ["justifies the cost", "market value", "engineering investment", "return", "worth the cost", "affordable"],
  },
  differentiation: {
    core: ["competitive differentiation", "unique feature", "differentiat"],
    related: [
      "competitive advantage", "positioning", "no direct equivalent",
      "unique product", "competit", "european equivalent",
    ],
  },
};

function findSharedCategories(condText, evText) {
  const shared = [];

  for (const [category, family] of Object.entries(CONCEPT_FAMILIES)) {
    /* Condition must contain a core word for this category */
    const condMatchesCore = family.core.some((kw) => condText.includes(kw));
    if (!condMatchesCore) continue;

    /* Evidence matches if it has either the same core word or any related word */
    const evMatches = [...family.core, ...family.related].some((kw) => evText.includes(kw));
    if (evMatches) {
      shared.push(category);
    }
  }

  return shared;
}

/* ── Core function ───────────────────────────────────────── */

/**
 * Assess the scope alignment between a decision condition and evidence.
 *
 * @param {{ condition: object, evidenceNode: object }} input
 * @returns {{ scope: "direct_match" | "partial_match" | "different_timeframe" | "unrelated" | "cannot_determine", reason: string }}
 */
export function assessEvidenceConditionScope({ condition, evidenceNode } = {}) {
  if (!condition) return { scope: "cannot_determine", reason: "missing or null condition" };
  if (!evidenceNode) return { scope: "cannot_determine", reason: "missing or null evidence node" };

  const conditionText = normalise(condition.text ?? condition.label ?? "");
  const evidenceText = normalise(evidenceNode.description ?? evidenceNode.text ?? evidenceNode.label ?? "");

  if (conditionText.length === 0) return { scope: "cannot_determine", reason: "empty condition text" };
  if (evidenceText.length === 0) return { scope: "cannot_determine", reason: "empty evidence node text" };

  /* Rule 1 — Timeframe mismatch (applies across all subjects) */

  const condIsPresent = isPresentState(conditionText);
  const condIsFuture = isFutureFeasibility(conditionText);
  const evIsPresent = isPresentState(evidenceText);
  const evIsFuture = isFutureFeasibility(evidenceText);

  if ((condIsPresent && evIsFuture) || (condIsFuture && evIsPresent)) {
    return { scope: "different_timeframe", reason: "evidence describes present state while condition concerns future feasibility" };
  }

  /* Rule 2 — Shared category check */

  const shared = findSharedCategories(conditionText, evidenceText);

  if (shared.length === 0) {
    /* Feasibility evidence without shared subject — both are feasibility-oriented */
    if (condIsFuture && evIsFuture) {
      return { scope: "partial_match", reason: "both express future-feasibility but address different subjects" };
    }
    if (condIsFuture || evIsFuture) {
      return { scope: "different_timeframe", reason: "evidence describes present state while condition concerns future feasibility" };
    }
    return { scope: "unrelated", reason: "condition and evidence do not share a recognisable concept category" };
  }

  /* Rule 3 — Both present-state → direct match */

  if (condIsPresent && evIsPresent) {
    return { scope: "direct_match", reason: `both describe present state in ${shared.join(" / ")} category` };
  }

  /* Rule 4 — Future condition with feasibility evidence → partial match */

  if ((condIsFuture || evIsFuture)) {
    return { scope: "partial_match", reason: `evidence addresses feasibility for ${shared.join(" / ")} but does not fully answer the condition` };
  }

  /* Fallback — cannot determine when neither present nor future detected */

  return { scope: "cannot_determine", reason: "neither present-state nor future-feasibility patterns detected in both texts" };
}