// The canonical ModelOp alphabet — every mutation to a SysMLModel is
// expressible as one or more of these. See docs/sync.md §3 for the design.
//
// `tempId` lets clients optimistically create elements with a client-generated
// id; applyOps may rewrite to a canonical id and return the mapping. (M5
// in-memory: tempId IS the canonical id; the rewrite seam is here for the
// later DB / SSE iteration.)

import type {
  Block,
  BlockKind,
  Association,
  AssociationKind,
  Constraint,
  Property,
  PropertyType,
  Multiplicity,
  Requirement,
  RequirementRelation,
} from "../sysml/model";

// ─── Block ops ───────────────────────────────────────────────────────────

export interface AddBlockOp {
  kind: "add-block";
  block: Block;
  tempId?: string;
}

export interface UpdateBlockOp {
  kind: "update-block";
  blockId: string;
  patch: Partial<Pick<Block, "label" | "kind" | "stereotypes" | "description">>;
}

export interface RemoveBlockOp {
  kind: "remove-block";
  blockId: string;
}

// ─── Property ops ────────────────────────────────────────────────────────

export interface AddPropertyOp {
  kind: "add-property";
  blockId: string;
  property: Property;
  tempId?: string;
}

export interface UpdatePropertyOp {
  kind: "update-property";
  blockId: string;
  propertyId: string;
  patch: Partial<Pick<Property, "name" | "type" | "multiplicity" | "description">>;
}

export interface RemovePropertyOp {
  kind: "remove-property";
  blockId: string;
  propertyId: string;
}

// ─── Association ops ─────────────────────────────────────────────────────

export interface AddAssociationOp {
  kind: "add-association";
  association: Association;
  tempId?: string;
}

export interface UpdateAssociationOp {
  kind: "update-association";
  associationId: string;
  patch: Partial<Pick<Association, "fromBlockId" | "toBlockId" | "label" | "kind" | "multiplicity">>;
}

export interface RemoveAssociationOp {
  kind: "remove-association";
  associationId: string;
}

// ─── Constraint ops ──────────────────────────────────────────────────────

export interface AddConstraintOp {
  kind: "add-constraint";
  constraint: Constraint;
  tempId?: string;
}

export interface UpdateConstraintOp {
  kind: "update-constraint";
  constraintId: string;
  patch: Partial<Pick<Constraint, "label" | "expression" | "appliesTo">>;
}

export interface RemoveConstraintOp {
  kind: "remove-constraint";
  constraintId: string;
}

// ─── Requirement ops ─────────────────────────────────────────────────────

export interface AddRequirementOp {
  kind: "add-requirement";
  requirement: Requirement;
  tempId?: string;
}

export interface UpdateRequirementOp {
  kind: "update-requirement";
  requirementId: string;
  patch: Partial<Pick<Requirement, "tag" | "text">>;
}

export interface RemoveRequirementOp {
  kind: "remove-requirement";
  requirementId: string;
}

export interface AddRelationOp {
  kind: "add-relation";
  requirementId: string;
  relation: RequirementRelation;
}

export interface RemoveRelationOp {
  kind: "remove-relation";
  requirementId: string;
  relationIndex: number;
}

// ─── Union ───────────────────────────────────────────────────────────────

export type ModelOp =
  | AddBlockOp
  | UpdateBlockOp
  | RemoveBlockOp
  | AddPropertyOp
  | UpdatePropertyOp
  | RemovePropertyOp
  | AddAssociationOp
  | UpdateAssociationOp
  | RemoveAssociationOp
  | AddConstraintOp
  | UpdateConstraintOp
  | RemoveConstraintOp
  | AddRequirementOp
  | UpdateRequirementOp
  | RemoveRequirementOp
  | AddRelationOp
  | RemoveRelationOp;

// ─── Op constructors (call sites stay readable) ─────────────────────────

export function addBlock(block: Block, tempId?: string): AddBlockOp {
  return { kind: "add-block", block, tempId };
}

export function updateBlock(blockId: string, patch: UpdateBlockOp["patch"]): UpdateBlockOp {
  return { kind: "update-block", blockId, patch };
}

export function removeBlock(blockId: string): RemoveBlockOp {
  return { kind: "remove-block", blockId };
}

export function addProperty(blockId: string, property: Property, tempId?: string): AddPropertyOp {
  return { kind: "add-property", blockId, property, tempId };
}

export function updateProperty(blockId: string, propertyId: string, patch: UpdatePropertyOp["patch"]): UpdatePropertyOp {
  return { kind: "update-property", blockId, propertyId, patch };
}

export function removeProperty(blockId: string, propertyId: string): RemovePropertyOp {
  return { kind: "remove-property", blockId, propertyId };
}

export function addAssociation(association: Association, tempId?: string): AddAssociationOp {
  return { kind: "add-association", association, tempId };
}

export function updateAssociation(associationId: string, patch: UpdateAssociationOp["patch"]): UpdateAssociationOp {
  return { kind: "update-association", associationId, patch };
}

export function removeAssociation(associationId: string): RemoveAssociationOp {
  return { kind: "remove-association", associationId };
}

export function addConstraint(constraint: Constraint, tempId?: string): AddConstraintOp {
  return { kind: "add-constraint", constraint, tempId };
}

export function updateConstraint(constraintId: string, patch: UpdateConstraintOp["patch"]): UpdateConstraintOp {
  return { kind: "update-constraint", constraintId, patch };
}

export function removeConstraint(constraintId: string): RemoveConstraintOp {
  return { kind: "remove-constraint", constraintId };
}

export function addRequirement(requirement: Requirement, tempId?: string): AddRequirementOp {
  return { kind: "add-requirement", requirement, tempId };
}

export function updateRequirement(requirementId: string, patch: UpdateRequirementOp["patch"]): UpdateRequirementOp {
  return { kind: "update-requirement", requirementId, patch };
}

export function removeRequirement(requirementId: string): RemoveRequirementOp {
  return { kind: "remove-requirement", requirementId };
}

export function addRelation(requirementId: string, relation: RequirementRelation): AddRelationOp {
  return { kind: "add-relation", requirementId, relation };
}

export function removeRelation(requirementId: string, relationIndex: number): RemoveRelationOp {
  return { kind: "remove-relation", requirementId, relationIndex };
}

// ─── Helpers ─────────────────────────────────────────────────────────────

let counter = 0;
/** Generate a temp id. Distinct prefix so applyOps can recognize them. */
export function tempId(prefix = "tmp"): string {
  counter++;
  return `${prefix}_${Date.now().toString(36)}_${counter}`;
}

/** Quick property factory used by clients producing add-property ops. */
export function newProperty(name: string, type: PropertyType = { kind: "string" }, multiplicity: Multiplicity = "0..1"): Property {
  return { id: tempId("p"), name, type, multiplicity };
}