import { describe, it, expect, vi, beforeEach } from 'vitest';
import {
  processCallsFromExtracted,
  seedCrossFileReceiverTypes,
  extractConsumerAccessedKeys,
  processNextjsFetchRoutes,
  buildImplementorMap,
  mergeImplementorMaps,
} from '../../src/core/ingestion/call-processor.js';
import { extractReturnTypeName } from '../../src/core/ingestion/type-extractors/shared.js';
import {
  createResolutionContext,
  type ResolutionContext,
} from '../../src/core/ingestion/resolution-context.js';
import { createKnowledgeGraph } from '../../src/core/graph/graph.js';
import type {
  ExtractedCall,
  ExtractedFetchCall,
  ExtractedHeritage,
  FileConstructorBindings,
} from '../../src/core/ingestion/workers/parse-worker.js';

describe('processCallsFromExtracted', () => {
  let graph: ReturnType<typeof createKnowledgeGraph>;
  let ctx: ResolutionContext;

  beforeEach(() => {
    graph = createKnowledgeGraph();
    ctx = createResolutionContext();
  });

  it('creates CALLS relationship for same-file resolution', async () => {
    ctx.symbols.add('src/index.ts', 'helper', 'Function:src/index.ts:helper', 'Function');

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'helper',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].sourceId).toBe('Function:src/index.ts:main');
    expect(rels[0].targetId).toBe('Function:src/index.ts:helper');
    expect(rels[0].confidence).toBe(0.95);
    expect(rels[0].reason).toBe('same-file');
  });

  it('creates CALLS relationship for import-resolved resolution', async () => {
    ctx.symbols.add('src/utils.ts', 'format', 'Function:src/utils.ts:format', 'Function');
    ctx.importMap.set('src/index.ts', new Set(['src/utils.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'format',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].confidence).toBe(0.9);
    expect(rels[0].reason).toBe('import-resolved');
  });

  it('resolves unique global symbol with moderate confidence', async () => {
    ctx.symbols.add('src/other.ts', 'uniqueFunc', 'Function:src/other.ts:uniqueFunc', 'Function');

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'uniqueFunc',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].confidence).toBe(0.5);
    expect(rels[0].reason).toBe('global');
  });

  it('refuses ambiguous global symbols — no CALLS edge created', async () => {
    ctx.symbols.add('src/a.ts', 'render', 'Function:src/a.ts:render', 'Function');
    ctx.symbols.add('src/b.ts', 'render', 'Function:src/b.ts:render', 'Function');

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'render',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(0);
  });

  it('skips unresolvable calls', async () => {
    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'nonExistent',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);
    expect(graph.relationshipCount).toBe(0);
  });

  it('refuses non-callable symbols even when the name resolves', async () => {
    ctx.symbols.add('src/index.ts', 'Widget', 'Class:src/index.ts:Widget', 'Class');

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'Widget',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);
    expect(graph.relationshipCount).toBe(0);
  });

  it('refuses CALLS edges to Interface symbols', async () => {
    ctx.symbols.add(
      'src/types.ts',
      'Serializable',
      'Interface:src/types.ts:Serializable',
      'Interface',
    );
    ctx.importMap.set('src/index.ts', new Set(['src/types.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'Serializable',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);
    expect(graph.relationships.filter((r) => r.type === 'CALLS')).toHaveLength(0);
  });

  it('refuses CALLS edges to Enum symbols', async () => {
    ctx.symbols.add('src/status.ts', 'Status', 'Enum:src/status.ts:Status', 'Enum');
    ctx.importMap.set('src/index.ts', new Set(['src/status.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'Status',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);
    expect(graph.relationships.filter((r) => r.type === 'CALLS')).toHaveLength(0);
  });

  it('prefers same-file over import-resolved', async () => {
    ctx.symbols.add('src/index.ts', 'render', 'Function:src/index.ts:render', 'Function');
    ctx.symbols.add('src/utils.ts', 'render', 'Function:src/utils.ts:render', 'Function');
    ctx.importMap.set('src/index.ts', new Set(['src/utils.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'render',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Function:src/index.ts:render');
    expect(rels[0].reason).toBe('same-file');
  });

  it('handles multiple calls from the same file', async () => {
    ctx.symbols.add('src/index.ts', 'foo', 'Function:src/index.ts:foo', 'Function');
    ctx.symbols.add('src/index.ts', 'bar', 'Function:src/index.ts:bar', 'Function');

    const calls: ExtractedCall[] = [
      { filePath: 'src/index.ts', calledName: 'foo', sourceId: 'Function:src/index.ts:main' },
      { filePath: 'src/index.ts', calledName: 'bar', sourceId: 'Function:src/index.ts:main' },
    ];

    await processCallsFromExtracted(graph, calls, ctx);
    expect(graph.relationships.filter((r) => r.type === 'CALLS')).toHaveLength(2);
  });

  it('uses arity to disambiguate import-scoped callable candidates', async () => {
    ctx.symbols.add('src/logger.ts', 'log', 'Function:src/logger.ts:log', 'Function', {
      parameterCount: 0,
    });
    ctx.symbols.add('src/formatter.ts', 'log', 'Function:src/formatter.ts:log', 'Function', {
      parameterCount: 1,
    });
    ctx.importMap.set('src/index.ts', new Set(['src/logger.ts', 'src/formatter.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'log',
        sourceId: 'Function:src/index.ts:main',
        argCount: 1,
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Function:src/formatter.ts:log');
    expect(rels[0].reason).toBe('import-resolved');
  });

  it('refuses ambiguous call targets when arity does not produce a unique match', async () => {
    ctx.symbols.add('src/logger.ts', 'log', 'Function:src/logger.ts:log', 'Function', {
      parameterCount: 1,
    });
    ctx.symbols.add('src/formatter.ts', 'log', 'Function:src/formatter.ts:log', 'Function', {
      parameterCount: 1,
    });
    ctx.importMap.set('src/index.ts', new Set(['src/logger.ts', 'src/formatter.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'log',
        sourceId: 'Function:src/index.ts:main',
        argCount: 1,
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);
    expect(graph.relationships.filter((r) => r.type === 'CALLS')).toHaveLength(0);
  });

  it('calls progress callback', async () => {
    ctx.symbols.add('src/index.ts', 'foo', 'Function:src/index.ts:foo', 'Function');

    const calls: ExtractedCall[] = [
      { filePath: 'src/index.ts', calledName: 'foo', sourceId: 'Function:src/index.ts:main' },
    ];

    const onProgress = vi.fn();
    await processCallsFromExtracted(graph, calls, ctx, onProgress);

    expect(onProgress).toHaveBeenCalledWith(1, 1);
  });

  it('handles empty calls array', async () => {
    await processCallsFromExtracted(graph, [], ctx);
    expect(graph.relationshipCount).toBe(0);
  });

  // ---- Constructor-aware resolution (Phase 2) ----

  it('resolves constructor call to Class when no Constructor node exists', async () => {
    ctx.symbols.add('src/models.ts', 'User', 'Class:src/models.ts:User', 'Class');
    ctx.importMap.set('src/index.ts', new Set(['src/models.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'User',
        sourceId: 'Function:src/index.ts:main',
        callForm: 'constructor',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Class:src/models.ts:User');
    expect(rels[0].reason).toBe('import-resolved');
  });

  it('resolves constructor call to Constructor node over Class node', async () => {
    ctx.symbols.add('src/models.ts', 'User', 'Class:src/models.ts:User', 'Class');
    ctx.symbols.add('src/models.ts', 'User', 'Constructor:src/models.ts:User', 'Constructor', {
      parameterCount: 1,
    });
    ctx.importMap.set('src/index.ts', new Set(['src/models.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'User',
        sourceId: 'Function:src/index.ts:main',
        argCount: 1,
        callForm: 'constructor',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Constructor:src/models.ts:User');
  });

  it('refuses Class target without callForm=constructor (existing behavior)', async () => {
    ctx.symbols.add('src/models.ts', 'User', 'Class:src/models.ts:User', 'Class');
    ctx.importMap.set('src/index.ts', new Set(['src/models.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'User',
        sourceId: 'Function:src/index.ts:main',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(0);
  });

  it('constructor call falls back to callable types when no Constructor/Class found', async () => {
    ctx.symbols.add('src/utils.ts', 'Widget', 'Function:src/utils.ts:Widget', 'Function');
    ctx.importMap.set('src/index.ts', new Set(['src/utils.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'Widget',
        sourceId: 'Function:src/index.ts:main',
        callForm: 'constructor',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Function:src/utils.ts:Widget');
  });

  it('constructor arity filtering narrows overloaded constructors', async () => {
    ctx.symbols.add('src/models.ts', 'User', 'Constructor:src/models.ts:User(0)', 'Constructor', {
      parameterCount: 0,
    });
    ctx.symbols.add('src/models.ts', 'User', 'Constructor:src/models.ts:User(2)', 'Constructor', {
      parameterCount: 2,
    });
    ctx.importMap.set('src/index.ts', new Set(['src/models.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'User',
        sourceId: 'Function:src/index.ts:main',
        argCount: 2,
        callForm: 'constructor',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Constructor:src/models.ts:User(2)');
  });

  it('cannot discriminate same-arity overloads by parameter type (known limitation)', async () => {
    ctx.symbols.add('src/UserDao.ts', 'save', 'Function:src/UserDao.ts:save', 'Function', {
      parameterCount: 1,
    });
    ctx.symbols.add('src/RepoDao.ts', 'save', 'Function:src/RepoDao.ts:save', 'Function', {
      parameterCount: 1,
    });
    ctx.importMap.set('src/index.ts', new Set(['src/UserDao.ts', 'src/RepoDao.ts']));

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'save',
        sourceId: 'Function:src/index.ts:main',
        argCount: 1,
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx);
    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(0);
  });

  // ---- Return type inference (Phase 4) ----

  it('return type inference: binds variable to return type of callee', async () => {
    // getUser() returns User, and User has a save() method
    ctx.symbols.add('src/utils.ts', 'getUser', 'Function:src/utils.ts:getUser', 'Function', {
      returnType: 'User',
    });
    ctx.symbols.add('src/models.ts', 'User', 'Class:src/models.ts:User', 'Class');
    ctx.symbols.add('src/models.ts', 'save', 'Method:src/models.ts:save', 'Method', {
      ownerId: 'Class:src/models.ts:User',
    });
    ctx.importMap.set('src/index.ts', new Set(['src/utils.ts', 'src/models.ts']));

    // Binding: user = getUser() — getUser is not a class, so constructor path fails,
    // but return type inference should kick in
    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/index.ts',
        bindings: [{ scope: 'main@0', varName: 'user', calleeName: 'getUser' }],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'save',
        sourceId: 'Function:src/index.ts:main',
        receiverName: 'user',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Method:src/models.ts:save');
  });

  it('return type inference: unwraps Promise<User> to User', async () => {
    ctx.symbols.add('src/api.ts', 'fetchUser', 'Function:src/api.ts:fetchUser', 'Function', {
      returnType: 'Promise<User>',
    });
    ctx.symbols.add('src/models.ts', 'User', 'Class:src/models.ts:User', 'Class');
    ctx.symbols.add('src/models.ts', 'save', 'Method:src/models.ts:save', 'Method', {
      ownerId: 'Class:src/models.ts:User',
    });
    ctx.importMap.set('src/index.ts', new Set(['src/api.ts', 'src/models.ts']));

    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/index.ts',
        bindings: [{ scope: 'main@0', varName: 'user', calleeName: 'fetchUser' }],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'save',
        sourceId: 'Function:src/index.ts:main',
        receiverName: 'user',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Method:src/models.ts:save');
  });

  it('return type inference: skips when return type is primitive', async () => {
    ctx.symbols.add('src/utils.ts', 'getCount', 'Function:src/utils.ts:getCount', 'Function', {
      returnType: 'number',
    });
    ctx.importMap.set('src/index.ts', new Set(['src/utils.ts']));

    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/index.ts',
        bindings: [{ scope: 'main@0', varName: 'count', calleeName: 'getCount' }],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'toString',
        sourceId: 'Function:src/index.ts:main',
        receiverName: 'count',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    // No binding should be created for primitive return types
    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(0);
  });

  it('return type inference: skips ambiguous callees (multiple definitions)', async () => {
    ctx.symbols.add('src/a.ts', 'getData', 'Function:src/a.ts:getData', 'Function', {
      returnType: 'User',
    });
    ctx.symbols.add('src/b.ts', 'getData', 'Function:src/b.ts:getData', 'Function', {
      returnType: 'Repo',
    });

    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/index.ts',
        bindings: [{ scope: 'main@0', varName: 'data', calleeName: 'getData' }],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'save',
        sourceId: 'Function:src/index.ts:main',
        receiverName: 'data',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    // Ambiguous callee — don't guess
    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(0);
  });

  it('return type inference: prefers constructor binding over return type', async () => {
    // If the callee IS a class, constructor binding wins (existing behavior)
    ctx.symbols.add('src/models.ts', 'User', 'Class:src/models.ts:User', 'Class');
    ctx.symbols.add('src/models.ts', 'save', 'Method:src/models.ts:save', 'Method', {
      ownerId: 'Class:src/models.ts:User',
    });
    ctx.importMap.set('src/index.ts', new Set(['src/models.ts']));

    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/index.ts',
        bindings: [{ scope: 'main@0', varName: 'user', calleeName: 'User' }],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'save',
        sourceId: 'Function:src/index.ts:main',
        receiverName: 'user',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Method:src/models.ts:save');
  });

  // ---- Scope-aware constructor bindings (Phase 3) ----

  it('receiverKey collision: same method name in different classes does not collide', async () => {
    // User.save@100 and Repo.save@200 are two methods named "save" in different classes.
    // Each has a local variable "db" pointing to a different type.
    // Without @startIndex in the key, the second binding would overwrite the first.
    ctx.symbols.add('src/db/Database.ts', 'Database', 'Class:src/db/Database.ts:Database', 'Class');
    ctx.symbols.add('src/db/Cache.ts', 'Cache', 'Class:src/db/Cache.ts:Cache', 'Class');
    ctx.symbols.add('src/db/Database.ts', 'query', 'Method:src/db/Database.ts:query', 'Method', {
      ownerId: 'Class:src/db/Database.ts:Database',
    });
    ctx.symbols.add('src/db/Cache.ts', 'query', 'Method:src/db/Cache.ts:query', 'Method', {
      ownerId: 'Class:src/db/Cache.ts:Cache',
    });
    ctx.importMap.set('src/models/User.ts', new Set(['src/db/Database.ts']));
    ctx.importMap.set('src/models/Repo.ts', new Set(['src/db/Cache.ts']));

    // Two bindings: both enclosing scope is named "save" but at different startIndexes
    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/models/User.ts',
        bindings: [
          // save@100: inside User.save(), db = new Database()
          { scope: 'save@100', varName: 'db', calleeName: 'Database' },
        ],
      },
      {
        filePath: 'src/models/Repo.ts',
        bindings: [
          // save@200: inside Repo.save(), db = new Cache()
          { scope: 'save@200', varName: 'db', calleeName: 'Cache' },
        ],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/models/User.ts',
        calledName: 'query',
        sourceId: 'Method:src/models/User.ts:save',
        receiverName: 'db',
        callForm: 'member',
      },
      {
        filePath: 'src/models/Repo.ts',
        calledName: 'query',
        sourceId: 'Method:src/models/Repo.ts:save',
        receiverName: 'db',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(2);
    const userQueryRel = rels.find((r) => r.sourceId === 'Method:src/models/User.ts:save');
    const repoQueryRel = rels.find((r) => r.sourceId === 'Method:src/models/Repo.ts:save');
    expect(userQueryRel?.targetId).toBe('Method:src/db/Database.ts:query');
    expect(repoQueryRel?.targetId).toBe('Method:src/db/Cache.ts:query');
  });

  it('receiverKey collision: same scope funcName + same varName + same type resolves (non-ambiguous)', async () => {
    // Two save@* scopes both bind "db" to the same type — not ambiguous, should resolve.
    ctx.symbols.add('src/db/Database.ts', 'Database', 'Class:src/db/Database.ts:Database', 'Class');
    ctx.symbols.add('src/db/Database.ts', 'query', 'Method:src/db/Database.ts:query', 'Method', {
      ownerId: 'Class:src/db/Database.ts:Database',
    });
    ctx.importMap.set('src/service.ts', new Set(['src/db/Database.ts']));

    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/service.ts',
        bindings: [
          { scope: 'save@10', varName: 'db', calleeName: 'Database' },
          { scope: 'save@50', varName: 'db', calleeName: 'Database' },
        ],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/service.ts',
        calledName: 'query',
        sourceId: 'Method:src/service.ts:save',
        receiverName: 'db',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(1);
    expect(rels[0].targetId).toBe('Method:src/db/Database.ts:query');
  });

  it('receiverKey collision: same scope funcName + same varName + different types → ambiguous, no CALLS edge', async () => {
    // Two save@* scopes in the same file bind "db" to different types — truly ambiguous.
    ctx.symbols.add('src/db/Database.ts', 'Database', 'Class:src/db/Database.ts:Database', 'Class');
    ctx.symbols.add('src/db/Cache.ts', 'Cache', 'Class:src/db/Cache.ts:Cache', 'Class');
    ctx.symbols.add('src/db/Database.ts', 'query', 'Method:src/db/Database.ts:query', 'Method', {
      ownerId: 'Class:src/db/Database.ts:Database',
    });
    ctx.symbols.add('src/db/Cache.ts', 'query', 'Method:src/db/Cache.ts:query', 'Method', {
      ownerId: 'Class:src/db/Cache.ts:Cache',
    });
    ctx.importMap.set('src/service.ts', new Set(['src/db/Database.ts', 'src/db/Cache.ts']));

    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/service.ts',
        bindings: [
          { scope: 'save@10', varName: 'db', calleeName: 'Database' },
          { scope: 'save@50', varName: 'db', calleeName: 'Cache' },
        ],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/service.ts',
        calledName: 'query',
        sourceId: 'Method:src/service.ts:save',
        receiverName: 'db',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    // Ambiguous — different types for same funcName+varName, should not emit a CALLS edge
    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(0);
  });

  it('scope-aware bindings: same varName in different functions resolves to correct type', async () => {
    ctx.symbols.add('src/models.ts', 'User', 'Class:src/models.ts:User', 'Class');
    ctx.symbols.add('src/models.ts', 'Repo', 'Class:src/models.ts:Repo', 'Class');
    ctx.symbols.add('src/models.ts', 'save', 'Function:src/models.ts:save', 'Function');
    ctx.importMap.set('src/index.ts', new Set(['src/models.ts']));

    const constructorBindings: FileConstructorBindings[] = [
      {
        filePath: 'src/index.ts',
        bindings: [
          { scope: 'processUser@12', varName: 'obj', calleeName: 'User' },
          { scope: 'processRepo@89', varName: 'obj', calleeName: 'Repo' },
        ],
      },
    ];

    const calls: ExtractedCall[] = [
      {
        filePath: 'src/index.ts',
        calledName: 'save',
        sourceId: 'Function:src/index.ts:processUser',
        receiverName: 'obj',
        callForm: 'member',
      },
      {
        filePath: 'src/index.ts',
        calledName: 'save',
        sourceId: 'Function:src/index.ts:processRepo',
        receiverName: 'obj',
        callForm: 'member',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, constructorBindings);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(2);
    // Both calls should resolve, each with the correct receiver type from their scope
    // (the important thing is they don't collide — without scope awareness,
    // last-write-wins would give both calls the same receiver type)
    expect(rels[0].sourceId).toBe('Function:src/index.ts:processUser');
    expect(rels[1].sourceId).toBe('Function:src/index.ts:processRepo');
  });
});

describe('extractReturnTypeName', () => {
  it('extracts simple type name', () => {
    expect(extractReturnTypeName('User')).toBe('User');
  });

  it('unwraps Promise<User>', () => {
    expect(extractReturnTypeName('Promise<User>')).toBe('User');
  });

  it('unwraps Option<User>', () => {
    expect(extractReturnTypeName('Option<User>')).toBe('User');
  });

  it('unwraps Result<User, Error> to first type arg', () => {
    expect(extractReturnTypeName('Result<User, Error>')).toBe('User');
  });

  it('strips nullable union: User | null', () => {
    expect(extractReturnTypeName('User | null')).toBe('User');
  });

  it('strips nullable union: User | undefined', () => {
    expect(extractReturnTypeName('User | undefined')).toBe('User');
  });

  it('strips nullable suffix: User?', () => {
    expect(extractReturnTypeName('User?')).toBe('User');
  });

  it('strips Go pointer: *User', () => {
    expect(extractReturnTypeName('*User')).toBe('User');
  });

  it('strips Rust reference: &User', () => {
    expect(extractReturnTypeName('&User')).toBe('User');
  });

  it('strips Rust mutable reference: &mut User', () => {
    expect(extractReturnTypeName('&mut User')).toBe('User');
  });

  it('returns undefined for primitives', () => {
    expect(extractReturnTypeName('string')).toBeUndefined();
    expect(extractReturnTypeName('number')).toBeUndefined();
    expect(extractReturnTypeName('boolean')).toBeUndefined();
    expect(extractReturnTypeName('void')).toBeUndefined();
    expect(extractReturnTypeName('int')).toBeUndefined();
  });

  it('returns undefined for genuine union types', () => {
    expect(extractReturnTypeName('User | Repo')).toBeUndefined();
  });

  it('returns undefined for empty string', () => {
    expect(extractReturnTypeName('')).toBeUndefined();
  });

  it('extracts qualified type: models.User → User', () => {
    expect(extractReturnTypeName('models.User')).toBe('User');
  });

  it('handles non-wrapper generics: Map<K, V> → Map', () => {
    expect(extractReturnTypeName('Map<string, User>')).toBe('Map');
  });

  it('handles nested wrapper: Promise<Option<User>>', () => {
    // Promise<Option<User>> → unwrap Promise → Option<User> → unwrap Option → User
    expect(extractReturnTypeName('Promise<Option<User>>')).toBe('User');
  });

  it('returns base type for collection generics (not unwrapped)', () => {
    expect(extractReturnTypeName('Vec<User>')).toBe('Vec');
    expect(extractReturnTypeName('List<User>')).toBe('List');
    expect(extractReturnTypeName('Array<User>')).toBe('Array');
    expect(extractReturnTypeName('Set<User>')).toBe('Set');
    expect(extractReturnTypeName('ArrayList<User>')).toBe('ArrayList');
  });

  it('unwraps Optional<User>', () => {
    expect(extractReturnTypeName('Optional<User>')).toBe('User');
  });

  it('extracts Ruby :: qualified type: Models::User → User', () => {
    expect(extractReturnTypeName('Models::User')).toBe('User');
  });

  it('extracts C++ :: qualified type: ns::HttpClient → HttpClient', () => {
    expect(extractReturnTypeName('ns::HttpClient')).toBe('HttpClient');
  });

  it('extracts deep :: qualified type: crate::models::User → User', () => {
    expect(extractReturnTypeName('crate::models::User')).toBe('User');
  });

  it('extracts mixed qualifier: ns.module::User → User', () => {
    expect(extractReturnTypeName('ns.module::User')).toBe('User');
  });

  it('returns undefined for lowercase :: qualified: std::vector', () => {
    expect(extractReturnTypeName('std::vector')).toBeUndefined();
  });

  it('extracts deep dot-qualified: com.example.models.User → User', () => {
    expect(extractReturnTypeName('com.example.models.User')).toBe('User');
  });

  it('unwraps wrapper over non-wrapper generic: Promise<Map<string, User>> → Map', () => {
    // Promise is a wrapper — unwrap it to get Map<string, User>.
    // Map is not a wrapper, so return its base type: Map.
    expect(extractReturnTypeName('Promise<Map<string, User>>')).toBe('Map');
  });

  it('unwraps doubly-nested wrapper: Future<Result<User, Error>> → User', () => {
    // Future → unwrap → Result<User, Error>; Result → unwrap first arg → User
    expect(extractReturnTypeName('Future<Result<User, Error>>')).toBe('User');
  });

  it('unwraps CompletableFuture<Optional<User>> → User', () => {
    // CompletableFuture → unwrap → Optional<User>; Optional → unwrap → User
    expect(extractReturnTypeName('CompletableFuture<Optional<User>>')).toBe('User');
  });

  // Rust smart pointer unwrapping
  it('unwraps Rc<User> → User', () => {
    expect(extractReturnTypeName('Rc<User>')).toBe('User');
  });
  it('unwraps Arc<User> → User', () => {
    expect(extractReturnTypeName('Arc<User>')).toBe('User');
  });
  it('unwraps Weak<User> → User', () => {
    expect(extractReturnTypeName('Weak<User>')).toBe('User');
  });
  it('unwraps MutexGuard<User> → User', () => {
    expect(extractReturnTypeName('MutexGuard<User>')).toBe('User');
  });
  it('unwraps RwLockReadGuard<User> → User', () => {
    expect(extractReturnTypeName('RwLockReadGuard<User>')).toBe('User');
  });
  it('unwraps Cow<User> → User', () => {
    expect(extractReturnTypeName('Cow<User>')).toBe('User');
  });
  // Nested: Arc<Option<User>> → User (double unwrap)
  it('unwraps Arc<Option<User>> → User', () => {
    expect(extractReturnTypeName('Arc<Option<User>>')).toBe('User');
  });
  // NOT unwrapped (containers/wrappers not in set)
  it('does not unwrap Mutex<User> (not a Deref wrapper)', () => {
    expect(extractReturnTypeName('Mutex<User>')).toBe('Mutex');
  });

  // Rust lifetime parameters in wrapper generics
  it("skips lifetime in Ref<'_, User> → User", () => {
    expect(extractReturnTypeName("Ref<'_, User>")).toBe('User');
  });
  it("skips lifetime in RefMut<'a, User> → User", () => {
    expect(extractReturnTypeName("RefMut<'a, User>")).toBe('User');
  });
  it("skips lifetime in MutexGuard<'_, User> → User", () => {
    expect(extractReturnTypeName("MutexGuard<'_, User>")).toBe('User');
  });

  it('returns undefined for lowercase non-class types', () => {
    expect(extractReturnTypeName('error')).toBeUndefined();
  });

  it('extracts PHP backslash-namespaced type: \\App\\Models\\User → User', () => {
    expect(extractReturnTypeName('\\App\\Models\\User')).toBe('User');
  });

  it('extracts PHP single-segment namespace: \\User → User', () => {
    expect(extractReturnTypeName('\\User')).toBe('User');
  });

  it('extracts PHP deep namespace: \\Vendor\\Package\\Sub\\Client → Client', () => {
    expect(extractReturnTypeName('\\Vendor\\Package\\Sub\\Client')).toBe('Client');
  });

  it('returns undefined for bare wrapper type names without generic arguments', () => {
    expect(extractReturnTypeName('Task')).toBeUndefined();
    expect(extractReturnTypeName('Promise')).toBeUndefined();
    expect(extractReturnTypeName('Future')).toBeUndefined();
    expect(extractReturnTypeName('Option')).toBeUndefined();
    expect(extractReturnTypeName('Result')).toBeUndefined();
    expect(extractReturnTypeName('Observable')).toBeUndefined();
    expect(extractReturnTypeName('ValueTask')).toBeUndefined();
    expect(extractReturnTypeName('CompletableFuture')).toBeUndefined();
    expect(extractReturnTypeName('Optional')).toBeUndefined();
  });

  // ---- Length caps (Phase 6) ----

  it('pre-cap: returns undefined when raw input exceeds 2048 characters', () => {
    const longInput = 'A'.repeat(2049);
    expect(extractReturnTypeName(longInput)).toBeUndefined();
  });

  it('pre-cap: accepts raw input at exactly 2048 characters (boundary)', () => {
    // A 2048-char string of uppercase letters passes the pre-cap gate.
    // It won't match as a valid identifier (too long for post-cap), so the
    // result is undefined — but the pre-cap itself does NOT reject it.
    // We test this by verifying a 2048-char type that WOULD be valid in all
    // other respects is still returned as undefined (post-cap rejects it).
    const atLimit = 'U' + 'x'.repeat(2047); // 2048 chars, starts with uppercase
    // Post-cap (512) will reject this, but the pre-cap should not fire.
    // The important assertion: no throw and the result is undefined from post-cap.
    expect(extractReturnTypeName(atLimit)).toBeUndefined();
  });

  it('pre-cap: accepts inputs shorter than 2048 characters without rejection', () => {
    // 'User' is well under 2048 — should resolve normally.
    expect(extractReturnTypeName('User')).toBe('User');
  });

  it('post-cap: returns undefined when extracted type name exceeds 512 characters', () => {
    // Construct a raw string that is under the 2048-char pre-cap but produces
    // a final identifier longer than 512 characters after extraction.
    // A bare uppercase identifier of 513 chars satisfies all rules except post-cap.
    const longTypeName = 'U' + 'x'.repeat(512); // 513 chars, starts with uppercase
    expect(extractReturnTypeName(longTypeName)).toBeUndefined();
  });

  it('post-cap: accepts extracted type name at exactly 512 characters (boundary)', () => {
    // 512-char identifier should pass the post-cap check (> 512 rejects, not >=).
    const atLimit = 'U' + 'x'.repeat(511); // exactly 512 chars
    expect(extractReturnTypeName(atLimit)).toBe(atLimit);
  });

  it('post-cap: accepts normal short type names well under 512 characters', () => {
    expect(extractReturnTypeName('HttpClient')).toBe('HttpClient');
    expect(extractReturnTypeName('UserService')).toBe('UserService');
  });
});

describe('seedCrossFileReceiverTypes', () => {
  it('single-hop: imported receiver gets type from ExportedTypeMap', () => {
    const calls: ExtractedCall[] = [
      {
        filePath: 'src/service.ts',
        calledName: 'save',
        sourceId: 'Function:src/service.ts:run',
        receiverName: 'repo',
        callForm: 'member',
      },
    ];

    const namedImportMap = new Map([
      [
        'src/service.ts',
        new Map([['repo', { sourcePath: 'src/models/repo.ts', exportedName: 'repo' }]]),
      ],
    ]);

    const exportedTypeMap = new Map([['src/models/repo.ts', new Map([['repo', 'Repo']])]]);

    const { enrichedCount } = seedCrossFileReceiverTypes(calls, namedImportMap, exportedTypeMap);

    expect(enrichedCount).toBe(1);
    expect(calls[0].receiverTypeName).toBe('Repo');
  });

  it('no-op when receiverTypeName already exists', () => {
    const calls: ExtractedCall[] = [
      {
        filePath: 'src/service.ts',
        calledName: 'save',
        sourceId: 'Function:src/service.ts:run',
        receiverName: 'repo',
        receiverTypeName: 'AlreadyKnown',
        callForm: 'member',
      },
    ];

    const namedImportMap = new Map([
      [
        'src/service.ts',
        new Map([['repo', { sourcePath: 'src/models/repo.ts', exportedName: 'repo' }]]),
      ],
    ]);

    const exportedTypeMap = new Map([['src/models/repo.ts', new Map([['repo', 'Repo']])]]);

    const { enrichedCount } = seedCrossFileReceiverTypes(calls, namedImportMap, exportedTypeMap);

    expect(enrichedCount).toBe(0);
    expect(calls[0].receiverTypeName).toBe('AlreadyKnown');
  });

  it('no-op for free function calls (callForm !== member)', () => {
    const calls: ExtractedCall[] = [
      {
        filePath: 'src/service.ts',
        calledName: 'doSomething',
        sourceId: 'Function:src/service.ts:run',
        receiverName: 'repo',
        callForm: 'free',
      },
    ];

    const namedImportMap = new Map([
      [
        'src/service.ts',
        new Map([['repo', { sourcePath: 'src/models/repo.ts', exportedName: 'repo' }]]),
      ],
    ]);

    const exportedTypeMap = new Map([['src/models/repo.ts', new Map([['repo', 'Repo']])]]);

    const { enrichedCount } = seedCrossFileReceiverTypes(calls, namedImportMap, exportedTypeMap);

    expect(enrichedCount).toBe(0);
    expect(calls[0].receiverTypeName).toBeUndefined();
  });

  it('aliased imports: local name maps to exported name via binding', () => {
    const calls: ExtractedCall[] = [
      {
        filePath: 'src/controller.ts',
        calledName: 'find',
        sourceId: 'Function:src/controller.ts:handle',
        receiverName: 'myRepo',
        callForm: 'member',
      },
    ];

    // import { repoInstance as myRepo } from 'src/models/repo.ts'
    const namedImportMap = new Map([
      [
        'src/controller.ts',
        new Map([['myRepo', { sourcePath: 'src/models/repo.ts', exportedName: 'repoInstance' }]]),
      ],
    ]);

    const exportedTypeMap = new Map([['src/models/repo.ts', new Map([['repoInstance', 'Repo']])]]);

    const { enrichedCount } = seedCrossFileReceiverTypes(calls, namedImportMap, exportedTypeMap);

    expect(enrichedCount).toBe(1);
    expect(calls[0].receiverTypeName).toBe('Repo');
  });

  it('early exit when maps are empty', () => {
    const calls: ExtractedCall[] = [
      {
        filePath: 'src/service.ts',
        calledName: 'save',
        sourceId: 'Function:src/service.ts:run',
        receiverName: 'repo',
        callForm: 'member',
      },
    ];

    const { enrichedCount: countA } = seedCrossFileReceiverTypes(
      calls,
      new Map(),
      new Map([['src/models/repo.ts', new Map([['repo', 'Repo']])]]),
    );
    expect(countA).toBe(0);

    const { enrichedCount: countB } = seedCrossFileReceiverTypes(
      calls,
      new Map([
        [
          'src/service.ts',
          new Map([['repo', { sourcePath: 'src/models/repo.ts', exportedName: 'repo' }]]),
        ],
      ]),
      new Map(),
    );
    expect(countB).toBe(0);

    expect(calls[0].receiverTypeName).toBeUndefined();
  });

  it('no mutation when no matching exports found', () => {
    const calls: ExtractedCall[] = [
      {
        filePath: 'src/service.ts',
        calledName: 'save',
        sourceId: 'Function:src/service.ts:run',
        receiverName: 'repo',
        callForm: 'member',
      },
    ];

    // namedImportMap has the file, but exportedTypeMap has no entry for the source path
    const namedImportMap = new Map([
      [
        'src/service.ts',
        new Map([['repo', { sourcePath: 'src/models/repo.ts', exportedName: 'repo' }]]),
      ],
    ]);

    const exportedTypeMap = new Map([['src/other-file.ts', new Map([['something', 'OtherType']])]]);

    const { enrichedCount } = seedCrossFileReceiverTypes(calls, namedImportMap, exportedTypeMap);

    expect(enrichedCount).toBe(0);
    expect(calls[0].receiverTypeName).toBeUndefined();
  });
});

describe('extractConsumerAccessedKeys', () => {
  it('extracts keys from destructuring after .json()', () => {
    const content = `
      const response = await fetch('/api/grants');
      const { data, pagination, error } = await response.json();
    `;
    const keys = extractConsumerAccessedKeys(content);
    expect(keys).toContain('data');
    expect(keys).toContain('pagination');
    expect(keys).toContain('error');
  });

  it('extracts keys from destructuring of data variable', () => {
    const content = `
      const data = await response.json();
      const { items, total } = data;
    `;
    const keys = extractConsumerAccessedKeys(content);
    expect(keys).toContain('items');
    expect(keys).toContain('total');
  });

  it('extracts keys from property access on data variable', () => {
    const content = `
      const data = await response.json();
      console.log(data.items);
      renderPagination(data.totalPages);
    `;
    const keys = extractConsumerAccessedKeys(content);
    expect(keys).toContain('items');
    expect(keys).toContain('totalPages');
  });

  it('extracts keys from optional chaining', () => {
    const content = `
      const result = await fetchData();
      const items = result?.items;
      const count = result?.count;
    `;
    const keys = extractConsumerAccessedKeys(content);
    expect(keys).toContain('items');
    expect(keys).toContain('count');
  });

  it('skips common method names like .json(), .map(), .filter()', () => {
    const content = `
      const data = await response.json();
      data.items.map(x => x.name);
      data.items.filter(x => x.active);
    `;
    const keys = extractConsumerAccessedKeys(content);
    expect(keys).toContain('items');
    expect(keys).not.toContain('json');
    expect(keys).not.toContain('map');
    expect(keys).not.toContain('filter');
  });

  it('returns empty array when no property accesses found', () => {
    const content = `
      function unrelated() {
        console.log('hello');
      }
    `;
    const keys = extractConsumerAccessedKeys(content);
    expect(keys).toHaveLength(0);
  });

  it('handles renamed destructuring bindings', () => {
    const content = `
      const { data: myData, error: err } = await res.json();
    `;
    const keys = extractConsumerAccessedKeys(content);
    expect(keys).toContain('data');
    expect(keys).toContain('error');
    // Should extract the original key names, not the aliases
    expect(keys).not.toContain('myData');
    expect(keys).not.toContain('err');
  });

  it('deduplicates keys accessed multiple times', () => {
    const content = `
      const { data } = await res.json();
      console.log(data.items);
      render(data.items);
    `;
    const keys = extractConsumerAccessedKeys(content);
    const dataCount = keys.filter((k) => k === 'data').length;
    expect(dataCount).toBe(1);
  });
});

describe('processNextjsFetchRoutes', () => {
  let graph: ReturnType<typeof createKnowledgeGraph>;

  beforeEach(() => {
    graph = createKnowledgeGraph();
  });

  it('creates FETCHES edge with basic reason when no consumer contents', () => {
    // Add a File node for the consumer
    graph.addNode({
      id: 'File:src/page.tsx',
      label: 'File',
      properties: { name: 'src/page.tsx', filePath: 'src/page.tsx' },
    });

    const fetchCalls: ExtractedFetchCall[] = [
      { filePath: 'src/page.tsx', fetchURL: '/api/grants', lineNumber: 10 },
    ];
    const routeRegistry = new Map([['/api/grants', 'src/app/api/grants/route.ts']]);

    processNextjsFetchRoutes(graph, fetchCalls, routeRegistry);

    const rels = graph.relationships.filter((r) => r.type === 'FETCHES');
    expect(rels).toHaveLength(1);
    expect(rels[0].reason).toBe('fetch-url-match');
  });

  it('creates FETCHES edge with accessed keys in reason when consumer contents provided', () => {
    graph.addNode({
      id: 'File:src/page.tsx',
      label: 'File',
      properties: { name: 'src/page.tsx', filePath: 'src/page.tsx' },
    });

    const fetchCalls: ExtractedFetchCall[] = [
      { filePath: 'src/page.tsx', fetchURL: '/api/grants', lineNumber: 10 },
    ];
    const routeRegistry = new Map([['/api/grants', 'src/app/api/grants/route.ts']]);

    const consumerContents = new Map([
      [
        'src/page.tsx',
        `
        const res = await fetch('/api/grants');
        const { data, pagination } = await res.json();
        console.log(data.items);
      `,
      ],
    ]);

    processNextjsFetchRoutes(graph, fetchCalls, routeRegistry, consumerContents);

    const rels = graph.relationships.filter((r) => r.type === 'FETCHES');
    expect(rels).toHaveLength(1);
    expect(rels[0].reason).toMatch(/^fetch-url-match\|keys:/);
    // Should contain the destructured keys
    expect(rels[0].reason).toContain('data');
    expect(rels[0].reason).toContain('pagination');
  });

  it('falls back to basic reason when consumer file has no property accesses', () => {
    graph.addNode({
      id: 'File:src/page.tsx',
      label: 'File',
      properties: { name: 'src/page.tsx', filePath: 'src/page.tsx' },
    });

    const fetchCalls: ExtractedFetchCall[] = [
      { filePath: 'src/page.tsx', fetchURL: '/api/grants', lineNumber: 10 },
    ];
    const routeRegistry = new Map([['/api/grants', 'src/app/api/grants/route.ts']]);

    const consumerContents = new Map([
      [
        'src/page.tsx',
        `
        // This file just fetches without accessing properties
        await fetch('/api/grants');
      `,
      ],
    ]);

    processNextjsFetchRoutes(graph, fetchCalls, routeRegistry, consumerContents);

    const rels = graph.relationships.filter((r) => r.type === 'FETCHES');
    expect(rels).toHaveLength(1);
    expect(rels[0].reason).toBe('fetch-url-match');
  });

  it('encodes fetch count in reason when consumer fetches multiple routes', () => {
    graph.addNode({
      id: 'File:src/dashboard.tsx',
      label: 'File',
      properties: { name: 'src/dashboard.tsx', filePath: 'src/dashboard.tsx' },
    });

    const fetchCalls: ExtractedFetchCall[] = [
      { filePath: 'src/dashboard.tsx', fetchURL: '/api/grants', lineNumber: 10 },
      { filePath: 'src/dashboard.tsx', fetchURL: '/api/users', lineNumber: 20 },
    ];
    const routeRegistry = new Map([
      ['/api/grants', 'src/app/api/grants/route.ts'],
      ['/api/users', 'src/app/api/users/route.ts'],
    ]);

    const consumerContents = new Map([
      [
        'src/dashboard.tsx',
        `
        const { data, pagination } = await grantsRes.json();
        const { users } = await usersRes.json();
      `,
      ],
    ]);

    processNextjsFetchRoutes(graph, fetchCalls, routeRegistry, consumerContents);

    const rels = graph.relationships.filter((r) => r.type === 'FETCHES');
    expect(rels).toHaveLength(2);
    // Both edges should have |fetches:2 suffix
    for (const rel of rels) {
      expect(rel.reason).toContain('|fetches:2');
      expect(rel.reason).toMatch(/^fetch-url-match\|keys:[^|]+\|fetches:2$/);
    }
  });

  it('does not encode fetch count when consumer fetches only one route', () => {
    graph.addNode({
      id: 'File:src/page.tsx',
      label: 'File',
      properties: { name: 'src/page.tsx', filePath: 'src/page.tsx' },
    });

    const fetchCalls: ExtractedFetchCall[] = [
      { filePath: 'src/page.tsx', fetchURL: '/api/grants', lineNumber: 10 },
    ];
    const routeRegistry = new Map([
      ['/api/grants', 'src/app/api/grants/route.ts'],
      ['/api/users', 'src/app/api/users/route.ts'],
    ]);

    const consumerContents = new Map([['src/page.tsx', `const { data } = await res.json();`]]);

    processNextjsFetchRoutes(graph, fetchCalls, routeRegistry, consumerContents);

    const rels = graph.relationships.filter((r) => r.type === 'FETCHES');
    expect(rels).toHaveLength(1);
    expect(rels[0].reason).not.toContain('|fetches:');
  });
});

describe('buildImplementorMap / mergeImplementorMaps', () => {
  it('records direct implements edges per interface name', () => {
    const heritage: ExtractedHeritage[] = [
      { filePath: 'a.java', className: 'C', parentName: 'Runnable', kind: 'implements' },
      { filePath: 'b.java', className: 'D', parentName: 'Runnable', kind: 'implements' },
    ];
    const map = buildImplementorMap(heritage);
    expect(map.get('Runnable')).toEqual(new Set(['a.java', 'b.java']));
  });

  it('ignores extends and other heritage kinds', () => {
    const heritage: ExtractedHeritage[] = [
      { filePath: 'a.java', className: 'C', parentName: 'Base', kind: 'extends' },
      { filePath: 'a.java', className: 'C', parentName: 'I', kind: 'implements' },
    ];
    const map = buildImplementorMap(heritage);
    expect(map.has('Base')).toBe(false);
    expect(map.get('I')).toEqual(new Set(['a.java']));
  });

  it('mergeImplementorMaps unions files per interface and adds new keys', () => {
    const acc = new Map<string, Set<string>>();
    mergeImplementorMaps(acc, new Map([['I', new Set(['a.java'])]]));
    mergeImplementorMaps(
      acc,
      new Map([
        ['I', new Set(['b.java'])],
        ['J', new Set(['c.java'])],
      ]),
    );
    expect(acc.get('I')).toEqual(new Set(['a.java', 'b.java']));
    expect(acc.get('J')).toEqual(new Set(['c.java']));
  });

  it('heritage merged across disjoint lists matches single buildImplementorMap (chunk-order invariant)', () => {
    const chunk1: ExtractedHeritage[] = [
      { filePath: 'a.java', className: 'A', parentName: 'Iface', kind: 'implements' },
    ];
    const chunk2: ExtractedHeritage[] = [
      { filePath: 'b.java', className: 'B', parentName: 'Iface', kind: 'implements' },
    ];
    const oneShot = buildImplementorMap([...chunk1, ...chunk2]);
    const acc = new Map<string, Set<string>>();
    mergeImplementorMaps(acc, buildImplementorMap(chunk1));
    mergeImplementorMaps(acc, buildImplementorMap(chunk2));
    expect(oneShot.get('Iface')).toEqual(acc.get('Iface'));
    expect(oneShot.get('Iface')).toEqual(new Set(['a.java', 'b.java']));
  });
});

describe('processCallsFromExtracted — interface dispatch', () => {
  let graph: ReturnType<typeof createKnowledgeGraph>;
  let ctx: ResolutionContext;

  beforeEach(() => {
    graph = createKnowledgeGraph();
    ctx = createResolutionContext();
    const ifaceFile = 'contracts/Action.java';
    const runnerFile = 'runner.java';
    const implA = 'impl/A.java';
    const implB = 'impl/B.java';
    const actionIfaceId = 'Interface:contracts/Action.java:Action';
    const ifaceExecuteId = 'Method:contracts/Action.java:execute';
    const implAExecuteId = 'Method:impl/A.java:execute';
    const implBExecuteId = 'Method:impl/B.java:execute';

    ctx.symbols.add(ifaceFile, 'Action', actionIfaceId, 'Interface');
    ctx.symbols.add(ifaceFile, 'execute', ifaceExecuteId, 'Method', { ownerId: actionIfaceId });
    ctx.symbols.add(implA, 'execute', implAExecuteId, 'Method');
    ctx.symbols.add(implB, 'execute', implBExecuteId, 'Method');
    ctx.importMap.set(runnerFile, new Set([ifaceFile]));

    graph.addNode({
      id: 'Function:runner.java:run',
      label: 'Function',
      properties: { name: 'run', filePath: runnerFile },
    });
    graph.addNode({
      id: actionIfaceId,
      label: 'Interface',
      properties: { name: 'Action', filePath: ifaceFile },
    });
    graph.addNode({
      id: ifaceExecuteId,
      label: 'Method',
      properties: { name: 'execute', filePath: ifaceFile },
    });
    graph.addNode({
      id: implAExecuteId,
      label: 'Method',
      properties: { name: 'execute', filePath: implA },
    });
    graph.addNode({
      id: implBExecuteId,
      label: 'Method',
      properties: { name: 'execute', filePath: implB },
    });
  });

  it('adds CALLS to interface method plus lower-confidence edges to implementing methods', async () => {
    const implementorMap = new Map<string, ReadonlySet<string>>([
      ['Action', new Set(['impl/A.java', 'impl/B.java'])],
    ]);

    const calls: ExtractedCall[] = [
      {
        filePath: 'runner.java',
        calledName: 'execute',
        sourceId: 'Function:runner.java:run',
        callForm: 'member',
        receiverName: 'action',
        receiverTypeName: 'Action',
      },
    ];

    await processCallsFromExtracted(graph, calls, ctx, undefined, undefined, implementorMap);

    const rels = graph.relationships.filter((r) => r.type === 'CALLS');
    expect(rels).toHaveLength(3);

    const primary = rels.find((r) => r.targetId === 'Method:contracts/Action.java:execute');
    const toA = rels.find((r) => r.targetId === 'Method:impl/A.java:execute');
    const toB = rels.find((r) => r.targetId === 'Method:impl/B.java:execute');
    expect(primary).toBeDefined();
    expect(primary!.confidence).toBeGreaterThan(0.7);
    expect(toA?.confidence).toBe(0.7);
    expect(toA?.reason).toBe('interface-dispatch');
    expect(toB?.confidence).toBe(0.7);
    expect(toB?.reason).toBe('interface-dispatch');
  });
});