rea/src/domain/javascript/javascriptSourceCoordinates.ts

import { z } from "zod";
import type {
  JavaScriptSourcePoint,
  JavaScriptSourceRange,
} from "./javascriptStaticAnalysisTypes.js";

/** Compare parser coordinates by line, then UTF-16 column. */
export const compareJavaScriptSourcePoints = (
  left: JavaScriptSourcePoint,
  right: JavaScriptSourcePoint,
): number => left.line - right.line || left.column - right.column;

/** Include equal endpoints without implying runtime reachability. */
export const javascriptSourceRangeContains = (
  outer: JavaScriptSourceRange,
  inner: JavaScriptSourceRange,
): boolean =>
  compareJavaScriptSourcePoints(outer.start, inner.start) <= 0 &&
  compareJavaScriptSourcePoints(outer.end, inner.end) >= 0;

/** Exact artifact-local coordinate key; callers supply the artifact identity. */
export const javascriptSourceRangeKey = (
  range: JavaScriptSourceRange,
): string =>
  `${range.start.line}:${range.start.column}-${range.end.line}:${range.end.column}`;

const sourcePointSchema = z.strictObject({
  line: z.number().int().min(1),
  column: z.number().int().min(0),
});

/** JavaScript source coordinates use one-based lines and zero-based columns. */
export const javascriptSourceRangeSchema = z
  .strictObject({ start: sourcePointSchema, end: sourcePointSchema })
  .superRefine((range, context) => {
    if (compareJavaScriptSourcePoints(range.end, range.start) < 0)
      context.addIssue({
        code: "custom",
        path: ["end"],
        message: "Source range end must not precede its start",
      });
  })
  .describe(
    "One-based lines, zero-based UTF-16 columns; start inclusive, end exclusive.",
  );