import { parseManifestUseCases } from "./_manifest-ast.js";
import { manifestPathForFeature } from "./_manifest-source.js";
import { repoRootSchema } from "./_rule-schema.js";
import { resolveRuleContext } from "./_rule-context.js";

/** @type {import("eslint").Rule.RuleModule} */
export default {
  meta: {
    type: "suggestion",
    docs: {
      description:
        'rateLimit.consume("X", _) inside a use-case file must match a budget declared in manifest.useCases[name].rateLimit.',
    },
    schema: repoRootSchema,
    messages: {
      undeclared:
        '{{useCase}} calls rateLimit.consume("{{budget}}") but "{{budget}}" is not declared in manifest.useCases.{{useCase}}.rateLimit. Add it to the manifest or remove the call.',
      unusedDeclaration:
        '{{useCase}} declares rateLimit budget "{{budget}}" in the manifest but rateLimit.consume("{{budget}}") is never called in this file. Add the consume call or remove the manifest declaration.',
    },
  },
  create(context) {
    const rc = resolveRuleContext(context);
    if (!rc) return {};
    const { useCaseName, featureRoot } = rc;
    const manifest = parseManifestUseCases(manifestPathForFeature(featureRoot));
    if (!manifest || !manifest[useCaseName]) return {};
    const declared = new Set(manifest[useCaseName].rateLimit ?? []);
    const consumed = new Set();

    return {
      CallExpression(node) {
        if (
          node.callee.type === "MemberExpression" &&
          node.callee.object.type === "Identifier" &&
          node.callee.object.name === "rateLimit" &&
          node.callee.property.type === "Identifier" &&
          node.callee.property.name === "consume" &&
          node.arguments.length > 0 &&
          node.arguments[0].type === "Literal" &&
          typeof node.arguments[0].value === "string"
        ) {
          const budget = node.arguments[0].value;
          consumed.add(budget);
          if (!declared.has(budget)) {
            context.report({
              node,
              messageId: "undeclared",
              data: { budget, useCase: useCaseName },
            });
          }
        }
      },
      "Program:exit"(node) {
        for (const budget of declared) {
          if (!consumed.has(budget)) {
            context.report({
              node,
              messageId: "unusedDeclaration",
              data: { budget, useCase: useCaseName },
            });
          }
        }
      },
    };
  },
};