import { describe, expect, it } from "vitest";
import {
  formulateQuestion,
  formulateTieResolutionQuestion,
} from "@/lib/graph/question-formulator.js";
import {
  explainUnknownSelection,
  selectActiveUnknownCandidate,
} from "@/lib/graph/utils.js";
import { ambiguityGeneralisationFixtures } from "@/tests/fixtures/ambiguity-generalisation.js";

function neutraliseUnknownLabels(graph) {
  let counter = 0;
  return {
    ...graph,
    nodes: graph.nodes.map((node) => {
      if (node.kind !== "unknown") return { ...node };
      counter += 1;
      return {
        ...node,
        label: `Unknown ${String.fromCharCode(64 + counter)}`,
        description: `Unknown factor ${counter}.`,
      };
    }),
  };
}

function isSingleQuestion(question) {
  return (question.match(/\?/g) || []).length === 1;
}

describe("ambiguity generalisation", () => {
  it("preserves ambiguity across contradiction scenarios without favouring one explanation", () => {
    const summary = ambiguityGeneralisationFixtures.map((fixture) => {
      const explanation = explainUnknownSelection(fixture.graph, []);
      const selection = selectActiveUnknownCandidate(fixture.graph, []);
      const neutralExplanation = explainUnknownSelection(
        neutraliseUnknownLabels(fixture.graph),
        [],
      );
      const tieQuestion = formulateTieResolutionQuestion({
        graph: fixture.graph,
      });
      const representativeUnknown = fixture.graph.nodes.find(
        (node) => node.kind === "unknown",
      );
      const fallbackQuestion = formulateQuestion({
        node: representativeUnknown,
        graph: fixture.graph,
      });

      const lowerQuestion = tieQuestion.question.toLowerCase();
      for (const term of fixture.disallowedQuestionTerms) {
        expect(lowerQuestion).not.toContain(term.toLowerCase());
      }

      expect(explanation.status).toBe("ambiguous");
      expect(selection.status).toBe("ambiguous");
      expect(selection.selectedNode).toBeNull();
      expect(explanation.selectedNodeId).toBeNull();
      expect(explanation.candidates).toHaveLength(2);
      expect(explanation.summary.selectedReason).toBe(
        "No justified distinction between leading unknowns.",
      );
      expect(explanation.alphabeticalUsedAsReasoning).toBe(false);
      expect(neutralExplanation.status).toBe("ambiguous");
      expect(isSingleQuestion(tieQuestion.question)).toBe(true);
      expect(tieQuestion.question.toLowerCase()).not.toContain(" or ");

      return {
        scenario: fixture.scenario,
        candidateCount: explanation.candidates.length,
        ambiguityStatus: explanation.status,
        tieReason: explanation.summary.selectedReason,
        investigationStrategy: tieQuestion.strategy,
        question: tieQuestion.question,
        explanationFavoured: explanation.selectedNodeId !== null,
      };
    });

    expect(summary).toMatchInlineSnapshot(`
      [
        {
          "ambiguityStatus": "ambiguous",
          "candidateCount": 2,
          "explanationFavoured": false,
          "investigationStrategy": null,
          "question": "Were these figures measured on the same basis and at the same scale?",
          "scenario": "Revenue increased by 18%, but cash in the bank fell over the same period.",
          "tieReason": "No justified distinction between leading unknowns.",
        },
        {
          "ambiguityStatus": "ambiguous",
          "candidateCount": 2,
          "explanationFavoured": false,
          "investigationStrategy": null,
          "question": "Were these figures measured over the same period and at the same scale?",
          "scenario": "Customer satisfaction scores increased, but complaints also increased.",
          "tieReason": "No justified distinction between leading unknowns.",
        },
        {
          "ambiguityStatus": "ambiguous",
          "candidateCount": 2,
          "explanationFavoured": false,
          "investigationStrategy": null,
          "question": "Were these figures measured over the same period and at the same scale?",
          "scenario": "Average delivery time decreased by 25%, but order cancellations increased.",
          "tieReason": "No justified distinction between leading unknowns.",
        },
        {
          "ambiguityStatus": "ambiguous",
          "candidateCount": 2,
          "explanationFavoured": false,
          "investigationStrategy": null,
          "question": "Were these figures measured over the same period and at the same scale?",
          "scenario": "Website traffic doubled, but sales remained unchanged.",
          "tieReason": "No justified distinction between leading unknowns.",
        },
        {
          "ambiguityStatus": "ambiguous",
          "candidateCount": 2,
          "explanationFavoured": false,
          "investigationStrategy": null,
          "question": "Were these figures measured over the same period and at the same scale?",
          "scenario": "Production output increased by 30%, but quality defects also increased.",
          "tieReason": "No justified distinction between leading unknowns.",
        },
      ]
    `);
  });
});