import {
  parse,
  Source,
  validate,
  specifiedRules,
  PossibleFragmentSpreadsRule,
  NoUnusedVariablesRule,
  GraphQLError,
  print,
  printSchema,
  visit,
  TypeInfo,
  visitWithTypeInfo,
  getNamedType,
  isNonNullType,
  isListType,
  isObjectType,
  isInputObjectType,
  isScalarType,
  isEnumType,
  typeFromAST,
  type GraphQLType,
  type SelectionSetNode,
  type FragmentDefinitionNode,
  type ValueNode,
  type ASTNode,
  type DocumentNode,
  type DirectiveNode,
} from "graphql";
import { createHash } from "node:crypto";
import { canonicalJson } from "../capability-model/evolution.js";
import { readRepositorySource } from "../capability-language/source-loader.js";
import {
  valueType,
  type InterfaceRevision,
  type ValueType,
  type InterfaceRevisionId,
} from "../capability-model/types.js";
import { querySchema } from "./schema.js";
import { objectRow } from "./relational-schema.js";
import { workspaceQueryRootId } from "./root.js";
import { relationalCompiler } from "./relational-compile.js";
import { fragmentSources, type FragmentResolver } from "./fragments.js";
import { lowerQueryTree, stripQueryBoundaries } from "./tree.js";
import {
  QueryCompileError,
  type QueryDeclaration,
  type CheckedQuery,
  type QueryFieldEffect,
  type QueryUse,
  type QueryArgument,
  type QuerySelection,
} from "./types.js";

const fail = (code: string, message: string, node?: ASTNode): never => {
  const token = node?.loc?.startToken;
  throw new QueryCompileError(
    code,
    message,
    token
      ? {
          file: node!.loc!.source.name,
          line: token.line,
          column: token.column,
        }
      : undefined,
  );
};

/** Shared checker for authored queries and bounded public query documents.
 * Runtime execution receives its checked IR, never an unchecked document. */
export async function compileQuery(
  declaration: QueryDeclaration,
  interfaces: readonly InterfaceRevision[],
  read: (name: string) => Promise<string>,
  resolveFragment?: FragmentResolver,
): Promise<CheckedQuery> {
  const paths = [declaration.document, ...declaration.fragments];
  if (paths.length > 128 || new Set(paths).size !== paths.length)
    fail("QUERY_SOURCE_LIMIT", "Query files must be distinct and bounded to 128");
  const definitions: DocumentNode["definitions"][number][] = [];
  let totalBytes = 0;
  for (const path of paths) {
    if (
      !path.endsWith(".graphql") ||
      path.startsWith("/") ||
      path.split(/[\\/]/).some((part) => !part || part === "." || part === "..")
    )
      fail("QUERY_SOURCE_PATH", `Invalid query source path ${path}`);
    const text = await read(path);
    totalBytes += Buffer.byteLength(text);
    if (totalBytes > 262144) fail("QUERY_SOURCE_LIMIT", "Query sources exceed 256 KiB");
    const document = parse(new Source(text, path), { maxTokens: 10000 });
    definitions.push(...document.definitions);
  }
  const fragmentContracts = await fragmentSources(declaration, definitions, resolveFragment);
  let document: DocumentNode = { kind: "Document" as DocumentNode["kind"], definitions };
  if (definitions.length > 256 || Buffer.byteLength(print(document)) > 262144)
    fail("QUERY_SOURCE_LIMIT", "Expanded fragment sources exceed the query source budget");
  visit(document, {
    Directive(node) {
      if (node.name.value === "live")
        fail(
          "QUERY_RETIRED_DIRECTIVE",
          "@live is retired. Observations watch ordinary query values; use checked operations for mutations.",
          node,
        );
    },
  });
  const generated = querySchema(declaration, interfaces, document);
  // Identity belongs to the checked object result, including fragment results.
  // Schema membership deliberately excludes structured values and query wrappers.
  const identity = parse("query Identity { _camino { ref } }", { noLocation: true }).definitions[0]!;
  if (identity.kind !== "OperationDefinition") throw new Error("Invalid identity selection");
  const identitySelection = identity.selectionSet.selections[0]!;
  const identityTypes = new TypeInfo(generated.schema);
  document = visit(
    document,
    visitWithTypeInfo(identityTypes, {
      SelectionSet: {
        leave(node, _key, parentNode) {
          // An inline projection is part of its containing object. Its identity
          // remains that object's base interface, not the projected interface.
          if (parentNode && !Array.isArray(parentNode) && "kind" in parentNode && parentNode.kind === "InlineFragment")
            return;
          const parent = identityTypes.getParentType();
          const contract = parent && generated.byName.get(parent.name);
          if (!contract || contract.revisionId === workspaceQueryRootId) return;
          const hasIdentity = node.selections.some(
            (field) =>
              field.kind === "Field" &&
              field.name.value === "_camino" &&
              !field.alias &&
              !field.directives?.length &&
              field.selectionSet?.selections.some(
                (child) =>
                  child.kind === "Field" && child.name.value === "ref" && !child.alias && !child.directives?.length,
              ),
          );
          // GraphQL validation caches comparisons by AST identity. Each nominal
          // object must get its own metadata subtree, even though the spelling is
          // identical (its reference scalar can be different).
          if (!hasIdentity) return { ...node, selections: [...node.selections, structuredClone(identitySelection)] };
        },
      },
    }),
  );
  const operations = document.definitions.filter((entry) => entry.kind === "OperationDefinition");
  if (
    operations.length !== 1 ||
    operations[0]!.operation !== "query" ||
    operations[0]!.name?.value !== declaration.operation
  )
    fail("QUERY_UNSUPPORTED_FEATURE", "Exactly one named query matching the declaration is required");
  visit(document, {
    Field(node) {
      if (node.name.value === "_unavailable")
        fail("QUERY_AGGREGATE_TYPE", "No supported field exists at this operator path", node);
      if (node.name.value.startsWith("__")) fail("QUERY_UNSUPPORTED_FEATURE", "Introspection is not supported", node);
    },
    Directive(node) {
      if (!["include", "skip", "boundary"].includes(node.name.value))
        fail("QUERY_UNSUPPORTED_FEATURE", `Unsupported directive ${node.name.value}`, node);
    },
  });
  // Capability interfaces are nominal views of one graph object, not mutually
  // exclusive GraphQL object variants. Check overlap using declared requirements.
  const projectionTypes = new TypeInfo(generated.schema);
  const requires = (from: InterfaceRevisionId, to: InterfaceRevisionId, seen = new Set<string>()): boolean => {
    if (from === to) return true;
    if (seen.has(from)) return false;
    seen.add(from);
    return generated.contracts.get(from)?.requiredInterfaces?.some((id) => requires(id, to, seen)) ?? false;
  };
  visit(
    document,
    visitWithTypeInfo(projectionTypes, {
      Field(node) {
        const parent = projectionTypes.getParentType();
        const member =
          parent && generated.byName.get(parent.name)?.members.find((member) => member.displayName === node.name.value);
        if (member?.kind === "relationship") generated.target(member);
      },
      InlineFragment(node) {
        if (!node.typeCondition) return;
        const from = projectionTypes.getParentType();
        const a = from && generated.byName.get(from.name);
        const b = generated.byName.get(node.typeCondition.name.value);
        if (!a || !b || !requires(a.revisionId, b.revisionId))
          fail(
            "QUERY_UNSUPPORTED_FEATURE",
            "Inline interface projections currently require a declared interface requirement",
            node,
          );
      },
      FragmentSpread(node) {
        const fragment = document.definitions.find(
          (entry) => entry.kind === "FragmentDefinition" && entry.name.value === node.name.value,
        );
        if (
          fragment?.kind === "FragmentDefinition" &&
          fragment.typeCondition.name.value !== projectionTypes.getParentType()?.name
        )
          fail("QUERY_UNSUPPORTED_FEATURE", "Named fragments currently require the exact nominal root interface", node);
      },
    }),
  );
  const bindingVariables = new Set(
    [...fragmentContracts.values()]
      .filter((entry) => entry.mode === "reference")
      .flatMap((entry) => Object.values(entry.variables)),
  );
  const errors = validate(
    generated.schema,
    document,
    [
      ...specifiedRules.filter((rule) => rule !== PossibleFragmentSpreadsRule && rule !== NoUnusedVariablesRule),
      (context) => ({
        OperationDefinition: {
          leave(operation) {
            const used = new Set(context.getRecursiveVariableUsages(operation).map(({ node }) => node.name.value));
            for (const variable of operation.variableDefinitions ?? []) {
              const name = variable.variable.name.value;
              if (!used.has(name) && !bindingVariables.has(name))
                context.reportError(new GraphQLError(`Variable "$${name}" is never used.`, { nodes: variable }));
            }
          },
        },
      }),
    ],
    { maxErrors: 20 },
  );
  if (errors.length) {
    const error = errors[0]!;
    fail("QUERY_VALIDATION", error.message, error.nodes?.[0]);
  }
  const effects = new Map<string, QueryFieldEffect>();
  const fragments = new Map(
    document.definitions
      .filter((entry): entry is FragmentDefinitionNode => entry.kind === "FragmentDefinition")
      .map((entry) => [entry.name.value, entry]),
  );
  const mark = (id: InterfaceRevisionId, name: string, use: QueryUse, node: ASTNode) => {
    // The virtual extent has no provider/getter effect. Its membership is
    // linked separately, including when the query only selects references.
    if (id === workspaceQueryRootId) return;
    const contract = generated.contracts.get(id)!;
    const member = contract.members.find((entry) => entry.displayName === name);
    if (!member || member.kind === "operation" || member.kind === "module" || !member.queryRead)
      return fail("QUERY_FIELD_NOT_QUERYABLE", `${contract.displayName}.${name} is not queryable`, node);
    if (declaration.placement?.kind === "local") {
      const getter = member.operations.find(
        (operation) => operation.displayName === (member.kind === "value" ? "get" : "resolve"),
      );
      if (getter?.execution?.kind !== "snapshot")
        fail(
          "QUERY_LOCAL_DEPENDENCY",
          `Local query requires a graph snapshot getter for ${contract.displayName}.${name}; split the remote field or move the query to the server`,
          node,
        );
      if (member.queryRead.execution === "rpc-permitted")
        fail(
          "QUERY_LOCAL_DEPENDENCY",
          `Local query cannot include remote-compute field ${contract.displayName}.${name}`,
          node,
        );
    }
    const key = `${id}\0${member.id}`;
    const effect = effects.get(key) ?? {
      interfaceRevisionId: id,
      memberId: member.id,
      uses: [],
      execution: member.queryRead.execution,
    };
    if (!effect.uses.includes(use)) effect.uses.push(use);
    effects.set(key, effect);
    if (
      effect.execution === "rpc-permitted" &&
      !declaration.allowances.some(
        (allow) =>
          allow.interfaceRevisionId === id &&
          allow.memberId === member.id &&
          allow.uses.includes(use) &&
          allow.reason.trim(),
      )
    )
      fail("QUERY_RPC_CONSUMER_REASON", `${contract.displayName}.${name} needs an allowance for ${use}`, node);
    if (
      declaration.watch &&
      effect.execution === "rpc-permitted" &&
      !declaration.polling &&
      !member.operations.some((op) => op.displayName === "watch-start")
    )
      fail(
        "QUERY_WATCH_UNSUPPORTED",
        `${contract.displayName}.${name} has no watch; explicitly acknowledge polling or use a one-shot query`,
        node,
      );
  };
  const relational = relationalCompiler(generated, declaration, mark, fragments);
  const compiledPredicates = new WeakMap<ASTNode, import("./relational.js").QueryPredicate>();
  const inputEffects = (id: InterfaceRevisionId, value: ValueNode, use: "predicate" | "order") => {
    if (use === "predicate") {
      relational.predicate(objectRow(id), value);
      return;
    }
    if (value.kind === "Variable") {
      // A dynamic filter may name any field in its declared input type.
      for (const member of generated.contracts.get(id)!.members)
        if (member.kind === "value" && member.queryRead) mark(id, member.displayName, use, value);
    } else if (value.kind === "ListValue") value.values.forEach((child) => inputEffects(id, child, use));
    else if (value.kind === "ObjectValue")
      for (const field of value.fields) {
        mark(id, field.name.value, use, field);
      }
  };
  const info = new TypeInfo(generated.schema);
  visit(
    document,
    visitWithTypeInfo(info, {
      Field(node) {
        const parent = info.getParentType();
        const contract = parent && generated.byName.get(parent.name);
        if (!contract || node.name.value === "_camino") return;
        mark(contract.revisionId, node.name.value, "select", node);
        const member = contract.members.find((entry) => entry.displayName === node.name.value)!;
        if (member.kind !== "relationship" || (member.cardinality !== "many" && member.cardinality !== "many-unique"))
          return;
        const target = generated.target(member);
        const bounds = (node.arguments ?? []).filter(
          (argument) => argument.name.value === "first" || argument.name.value === "all",
        );
        if (bounds.length !== 1) fail("QUERY_ROW_LIMIT", "Specify exactly one of first or all", node);
        if (bounds[0]!.name.value === "all" && node.arguments?.some((argument) => argument.name.value === "after"))
          fail("QUERY_UNSUPPORTED_FEATURE", "Bounded-all does not accept a continuation", node);
        for (const argument of node.arguments ?? []) {
          if (argument.name.value === "where")
            compiledPredicates.set(
              node,
              relational.predicate(
                objectRow(target, member.keyType ? { keyType: member.keyType } : undefined),
                argument.value,
              ),
            );
          if (argument.name.value === "orderBy") inputEffects(target, argument.value, "order");
          if (
            ["first", "all"].includes(argument.name.value) &&
            argument.value.kind !== "Variable" &&
            (argument.value.kind !== "IntValue" ||
              Number(argument.value.value) < 1 ||
              Number(argument.value.value) > declaration.budgets.rows)
          )
            fail(
              "QUERY_ROW_LIMIT",
              `${argument.name.value} must be between 1 and ${declaration.budgets.rows}`,
              argument,
            );
        }
        if (node.arguments?.some((a) => a.name.value === "after")) {
          const rpcOrder = (value: ValueNode): boolean =>
            value.kind === "Variable"
              ? generated.contracts
                  .get(target)!
                  .members.some((m) => m.kind === "value" && m.queryRead?.execution === "rpc-permitted")
              : value.kind === "ListValue"
                ? value.values.some(rpcOrder)
                : value.kind === "ObjectValue" &&
                  value.fields.some((f) =>
                    generated.contracts
                      .get(target)!
                      .members.some(
                        (m) =>
                          m.displayName === f.name.value &&
                          m.kind === "value" &&
                          m.queryRead?.execution === "rpc-permitted",
                      ),
                  );
          const order = node.arguments.find((a) => a.name.value === "orderBy");
          if (relational.needsRpc(compiledPredicates.get(node)) || (order && rpcOrder(order.value)))
            fail(
              "QUERY_UNSUPPORTED_FEATURE",
              "RPC predicates/order require a bounded first/all window without continuation",
              node,
            );
        }
      },
      FragmentSpread(node) {
        const fragment = definitions.find(
          (entry) => entry.kind === "FragmentDefinition" && entry.name.value === node.name.value,
        ) as FragmentDefinitionNode;
        if (fragment.typeCondition.name.value !== info.getParentType()?.name)
          fail("QUERY_UNSUPPORTED_FEATURE", "Fragments must select the exact current type", node);
      },
    }),
  );
  let expandedFields = 0;
  // GraphQL merges repeated response keys. In particular, fragments may each
  // contribute different children of one relationship; last-write-wins would
  // silently remove fields from both the generated type and the wire codec.
  const mergeOutput = (left: ValueType, right: ValueType): ValueType => {
    const a = left.kind === "optional" ? left.value : left;
    const b = right.kind === "optional" ? right.value : right;
    let result = a;
    if (a.kind === "record" && b.kind === "record") {
      const fields = { ...a.fields };
      for (const [key, type] of Object.entries(b.fields))
        fields[key] = fields[key] ? mergeOutput(fields[key], type) : type;
      result = { kind: "record", fields };
    } else if (a.kind === "list" && b.kind === "list") result = valueType.list(mergeOutput(a.value, b.value));
    return left.kind === "optional" && right.kind === "optional" ? valueType.optional(result) : result;
  };
  const output = (type: GraphQLType, selections?: SelectionSetNode, depth = 0, conditional = false): ValueType => {
    if (depth > declaration.budgets.depth * 4 + 4) fail("QUERY_DEPTH_LIMIT", "Expanded query exceeds its depth budget");
    if (isNonNullType(type)) return required(type.ofType, selections, depth, conditional);
    return valueType.optional(required(type, selections, depth, conditional));
  };
  const required = (type: GraphQLType, selections?: SelectionSetNode, depth = 0, conditional = false): ValueType => {
    if (isListType(type)) return valueType.list(output(type.ofType, selections, depth, conditional));
    if (isObjectType(type)) {
      const fields: Record<string, ValueType> = {};
      const add = (set: SelectionSetNode, conditional = false, selectedType = type) => {
        for (const selection of set.selections) {
          if (++expandedFields > 10000) fail("QUERY_WORK_LIMIT", "Expanded query exceeds 10000 fields", selection);
          if (selection.kind === "FragmentSpread") {
            if (selection.directives?.some((directive) => directive.name.value === "boundary")) continue;
            if (fragmentContracts.get(selection.name.value)?.mode === "reference") continue;
            add(
              fragments.get(selection.name.value)!.selectionSet,
              conditional || !!selection.directives?.length,
              selectedType,
            );
            continue;
          }
          if (selection.kind === "InlineFragment") {
            const projected = selection.typeCondition
              ? generated.schema.getType(selection.typeCondition.name.value)
              : selectedType;
            if (!isObjectType(projected)) return fail("QUERY_TYPE", "Expected an object projection", selection);
            add(selection.selectionSet, conditional || !!selection.directives?.length, projected);
            continue;
          }
          if (selection.kind !== "Field") continue;
          const key = selection.alias?.value ?? selection.name.value;
          const field = selectedType.getFields()[selection.name.value]!;
          const previous = fields[key];
          fields[key] = output(
            field.type,
            selection.selectionSet,
            depth + 1,
            conditional || !!selection.directives?.some((entry) => entry.name.value !== "live"),
          );
          if (
            (conditional || selection.directives?.some((entry) => entry.name.value !== "live")) &&
            fields[key]!.kind !== "optional"
          )
            fields[key] = valueType.optional(fields[key]!);
          if (previous) fields[key] = mergeOutput(previous, fields[key]!);
        }
      };
      // A condition on this object makes the object optional, not every child
      // of the object when it is present. Fragment conditions are handled by add.
      if (selections) add(selections);
      return { kind: "record", fields };
    }
    return (
      generated.scalarTypes.get(getNamedType(type)!.name) ??
      fail("QUERY_TYPE", `Unsupported query scalar ${getNamedType(type)!.name}`)
    );
  };
  const variables: Record<string, ValueType> = {};
  const inputShape = (type: GraphQLType, seen = new Set<string>()): ValueType => {
    if (isNonNullType(type)) return inputRequired(type.ofType, seen);
    return valueType.optional(inputRequired(type, seen));
  };
  const inputRequired = (type: GraphQLType, seen: Set<string>): ValueType => {
    if (isListType(type)) return valueType.list(inputShape(type.ofType, seen));
    if (isInputObjectType(type)) {
      // Recursive boolean filter inputs need generated recursive TS shapes; never degrade to any.
      if (seen.has(type.name))
        fail(
          "QUERY_UNSUPPORTED_FEATURE",
          "Pass scalar variables inside fixed filter expressions instead of a whole recursive filter",
        );
      return {
        kind: "record",
        fields: Object.fromEntries(
          Object.entries(type.getFields()).map(([key, field]) => [
            key,
            inputShape(field.type, new Set([...seen, type.name])),
          ]),
        ),
      };
    }
    if (isEnumType(type)) return valueType.string;
    if (isScalarType(type))
      return generated.scalarTypes.get(type.name) ?? fail("QUERY_TYPE", `Unsupported query scalar ${type.name}`);
    return fail("QUERY_VARIABLE_TYPE", "Unsupported variable type");
  };
  for (const variable of operations[0]!.variableDefinitions ?? [])
    variables[variable.variable.name.value] = inputShape(typeFromAST(generated.schema, variable.type)!);
  const result = required(generated.schema.getQueryType()!, operations[0]!.selectionSet);
  const argument = (node: ValueNode): QueryArgument => {
    switch (node.kind) {
      case "Variable":
        return { kind: "variable", name: node.name.value };
      case "ListValue":
        return { kind: "list", values: node.values.map(argument) };
      case "ObjectValue":
        return {
          kind: "object",
          fields: Object.fromEntries(node.fields.map((field) => [field.name.value, argument(field.value)])),
        };
      case "NullValue":
        return { kind: "literal", value: null };
      case "BooleanValue":
        return { kind: "literal", value: node.value };
      // Int literals stay decimal until their checked field codec interprets them.
      default:
        return { kind: "literal", value: node.value };
    }
  };
  const conditions = (directives: readonly DirectiveNode[] = []) =>
    directives
      .filter((directive) => ["include", "skip"].includes(directive.name.value))
      .map((directive) => ({
        include: directive.name.value === "include",
        value: argument(directive.arguments!.find((entry) => entry.name.value === "if")!.value),
      }));
  const selection = (
    set: SelectionSetNode,
    parent: import("graphql").GraphQLObjectType,
    inherited: QuerySelection["conditions"] = [],
  ): QuerySelection[] => {
    const selections = set.selections.flatMap((node): QuerySelection[] => {
      if (node.kind === "InlineFragment") {
        const projected = node.typeCondition ? generated.schema.getType(node.typeCondition.name.value) : parent;
        if (!isObjectType(projected)) return fail("QUERY_TYPE", "Expected an object projection", node);
        return selection(node.selectionSet, projected, [...inherited, ...conditions(node.directives)]);
      }
      if (node.kind === "FragmentSpread") {
        const inheritedConditions = [...inherited, ...conditions(node.directives)];
        const contract = fragmentContracts.get(node.name.value);
        if (contract && generated.byName.get(parent.name)?.revisionId !== contract.root)
          fail("FRAGMENT_ROOT_MISMATCH", "Imported fragment requires its exact nominal root interface", node);
        const directive = node.directives?.find((directive) => directive.name.value === "boundary");
        if (directive) {
          const name = directive.arguments?.find((argument) => argument.name.value === "name")?.value;
          if (name?.kind !== "StringValue" || !/^[A-Za-z_][A-Za-z0-9_]{0,63}$/.test(name.value))
            return fail(
              "QUERY_BOUNDARY_NAME",
              "A boundary needs a literal identifier of at most 64 characters",
              directive,
            );
          const root = generated.byName.get(parent.name)?.revisionId;
          if (!root || root === workspaceQueryRootId)
            return fail("QUERY_BOUNDARY_ROOT", "A boundary must select a nominal Graph Object", node);
          if (contract?.mode === "reference")
            fail("QUERY_BOUNDARY_REFERENCE", "Use an ordinary checked Fragment spread for a boundary", node);
          const fragment = fragments.get(node.name.value)!;
          const token = node.loc?.startToken;
          return [
            {
              name: "$boundary",
              key: "",
              arguments: {},
              conditions: inheritedConditions,
              boundary: {
                name: name.value,
                root,
                output: required(parent, fragment.selectionSet),
                ...(token ? { location: { file: node.loc!.source.name, line: token.line, column: token.column } } : {}),
              },
              selection: [
                ...(contract
                  ? [
                      {
                        name: "$fragment",
                        key: "",
                        selection: [],
                        arguments: {},
                        conditions: [],
                        fragmentSpread: contract,
                      },
                    ]
                  : []),
                ...selection(fragment.selectionSet, parent),
              ],
            },
          ];
        }
        return [
          ...(contract
            ? [
                {
                  name: "$fragment",
                  key: "",
                  selection: [],
                  arguments: {},
                  conditions: inheritedConditions,
                  fragmentSpread: contract,
                },
              ]
            : []),
          ...(contract?.mode === "reference"
            ? []
            : selection(fragments.get(node.name.value)!.selectionSet, parent, inheritedConditions)),
        ];
      }
      if (node.kind !== "Field") return [];
      const contract = generated.byName.get(parent.name);
      const member = contract?.members.find((entry) => entry.displayName === node.name.value);
      const type = getNamedType(parent.getFields()[node.name.value]!.type);
      const referenceType = type && generated.scalarTypes.get(type.name);
      const role = generated.relational.roles.get(parent.name);
      const relationship =
        role?.kind === "relations"
          ? generated.relational.relations(role.row).find((m) => m.displayName === node.name.value)
          : undefined;
      const plan =
        relationship && role?.row.kind === "object" && node.selectionSet
          ? relational.plan(role.row.interfaceRevisionId, relationship, node.selectionSet, (set, name) => {
              const t = generated.schema.getType(name);
              if (!t || !isObjectType(t)) return fail("QUERY_TYPE", `Missing generated output type ${name}`, node);
              return selection(set, t);
            })
          : undefined;
      return [
        {
          name: node.name.value,
          key: node.alias?.value ?? node.name.value,
          ...(member && contract ? { interfaceRevisionId: contract.revisionId, memberId: member.id } : {}),
          ...(member?.kind === "relationship" ? { targetInterfaceRevisionId: generated.target(member) } : {}),
          ...(node.name.value === "ref" &&
          referenceType?.kind === "object-ref" &&
          referenceType.expectation.kind === "interface"
            ? { targetInterfaceRevisionId: referenceType.expectation.interfaceRevisionId }
            : {}),
          conditions: [...inherited, ...conditions(node.directives)],
          arguments: Object.fromEntries(
            (node.arguments ?? []).map((entry) => [entry.name.value, argument(entry.value)]),
          ),
          selection: node.selectionSet && isObjectType(type) ? selection(node.selectionSet, type) : [],
          ...(plan ? { relational: plan } : {}),
          ...(compiledPredicates.has(node) ? { predicate: compiledPredicates.get(node)! } : {}),
        },
      ];
    });
    const contract = generated.byName.get(parent.name);
    const names = new Set<string>();
    for (const field of selections)
      if (field.boundary) {
        if (names.has(field.boundary.name))
          fail("QUERY_BOUNDARY_DUPLICATE", `Duplicate boundary ${field.boundary.name}`);
        names.add(field.boundary.name);
      }
    if (!contract || contract.revisionId === workspaceQueryRootId) return selections;
    // Fragment expansion may repeat metadata. Combine its children so a later
    // implicit reference cannot overwrite an explicitly selected aggregate.
    const metadata = selections.filter((field) => field.key === "_camino" && field.name === "_camino");
    const responseFields = new Map<string, QuerySelection>();
    for (const field of selections.filter((field) => field.memberId)) {
      const previous = responseFields.get(field.key);
      if (
        previous &&
        (previous.interfaceRevisionId !== field.interfaceRevisionId || previous.memberId !== field.memberId)
      )
        fail("QUERY_PROJECTION_CONFLICT", `Alias distinct interface fields selected as ${field.key}`);
      responseFields.set(field.key, field);
    }
    if (!metadata.length) return selections;
    const children = metadata.flatMap((field) =>
      field.selection.map((child) => ({
        ...child,
        conditions: [...field.conditions, ...child.conditions],
      })),
    );
    const ref = children.find((child) => child.key === "ref" && child.name === "ref")!;
    return [
      ...selections.filter((field) => !metadata.includes(field)),
      {
        ...metadata[0]!,
        conditions: [],
        selection: [...children.filter((child) => child.key !== "ref"), { ...ref, conditions: [] }],
      },
    ];
  };
  const normalized = print(document),
    schema = printSchema(generated.schema);
  const selections = selection(operations[0]!.selectionSet, generated.schema.getQueryType()!);
  const tree = lowerQueryTree(declaration, selections, result);
  const definitionDigest = createHash("sha256")
    .update(
      canonicalJson({
        semantics: tree ? 7 : 6,
        declaration,
        normalized,
        fragmentContracts: Object.fromEntries(fragmentContracts),
        // Source provenance belongs to the checked installation. Identical public
        // contracts keep their query identity when retained in another repository.
        // Closed generic identity remains explicit in revisionId/application;
        // its template's retention source is provenance too. byName also holds
        // names probed while discovering nominal projections, so only include
        // interfaces actually present in the generated query schema.
        interfaces: Object.values(generated.schema.getTypeMap())
          .filter(isObjectType)
          .flatMap((type) => {
            const revision = generated.byName.get(type.name);
            if (!revision) return [];
            const { source: _source, application, ...contract } = revision;
            if (!application) return [contract];
            const { source: _templateSource, ...identity } = application;
            return [{ ...contract, application: identity }];
          })
          .sort((a, b) => (a.revisionId < b.revisionId ? -1 : a.revisionId > b.revisionId ? 1 : 0)),
      }),
    )
    .digest("hex");
  return {
    declaration,
    definitionDigest,
    document: normalized,
    schema,
    variables: { kind: "record", fields: variables },
    output: result,
    effects: [...effects.values()],
    selection: tree ? stripQueryBoundaries(selections) : selections,
    ...(tree ? { tree } : {}),
    variableDefaults: Object.fromEntries(
      (operations[0]!.variableDefinitions ?? [])
        .filter((entry) => entry.defaultValue)
        .map((entry) => [entry.variable.name.value, argument(entry.defaultValue!)]),
    ),
    sourceFiles: paths,
    ...(fragmentContracts.size ? { fragmentContracts: Object.fromEntries(fragmentContracts) } : {}),
  };
}

export const compileRepositoryQuery = async (
  root: string,
  declaration: QueryDeclaration,
  interfaces: readonly InterfaceRevision[],
  resolveFragment?: FragmentResolver,
) => {
  const started = performance.now();
  try {
    return await compileQuery(declaration, interfaces, (name) => readRepositorySource(root, name), resolveFragment);
  } finally {
    // Timing belongs in check logs, never in immutable artifact identities.
    console.error(
      `[query-check] ${JSON.stringify(declaration.displayName)}: ${(performance.now() - started).toFixed(1)}ms`,
    );
  }
};