// Convert the loose Aristotle FixtureData (M1 prototype port) into a strict
// SysMLModel that the validator and dep-graph can operate on.

import type {
  SysMLModel,
  Block,
  Association,
  Constraint,
  Requirement,
  AssociationKind,
} from "./model";
import type { FixtureData } from "../fixtures/aristotle";

export function fromFixture(data: FixtureData): SysMLModel {
  const constraintBlocks = data.blocks.filter(b => b.kind === "constraint");
  const constraints: Constraint[] = constraintBlocks.map(b => ({
    id: b.id,
    label: b.label,
    expression: "{ tenancy = institutional }",
    // The fixture infers "what does this constraint apply to?" from its
    // outgoing/incoming `kind: "constraint"` associations.
    appliesTo: data.associations
      .filter(a => a.kind === "constraint" && (a.from === b.id || a.to === b.id))
      .map(a => (a.from === b.id ? a.to : a.from)),
  }));

  const blocks: Block[] = data.blocks
    .filter(b => b.kind !== "constraint")
    .map(b => ({
      id: b.id,
      label: b.label,
      kind: b.kind,
      stereotypes: [b.kind],
      properties: b.properties.map((name, i) => ({
        id: `p${i + 1}`,
        name,
        type: { kind: "string" } as const,
        multiplicity: "0..1" as const,
      })),
    }));

  const associations: Association[] = data.associations
    .filter(a => a.kind !== "constraint")
    .map(a => ({
      id: a.id,
      fromBlockId: a.from,
      toBlockId: a.to,
      label: a.label,
      kind: mapAssocKind(a.kind),
    }));

  // Requirements come from the narrative; the fixture chips reference REQ-001..003
  // but the requirements themselves aren't stored. Fabricate them here so the
  // validator has something meaningful to operate on.
  const requirements: Requirement[] = [
    {
      id: "req-001",
      tag: "REQ-001",
      text: "Must never output a complete solution to a graded problem.",
      relations: [{ kind: "satisfy", blockId: "aristotle" }],
    },
    {
      id: "req-002",
      tag: "REQ-002",
      text: "Response latency under 1.2s P50 to preserve flow.",
      relations: [{ kind: "satisfy", blockId: "aristotle" }],
    },
    {
      id: "req-003",
      tag: "REQ-003",
      text: "Operates within FERPA boundaries; coursework never leaves institutional tenancy.",
      // Intentionally untraced in the fixture — see the rail's "untraced" dot
      relations: [],
    },
  ];

  return {
    blocks,
    associations,
    constraints,
    requirements,
  };
}

function mapAssocKind(k: "association" | "composition" | "constraint"): AssociationKind {
  if (k === "constraint") return "constraintApplies";
  return k;
}