// ============================================================================
// LangGraph State Management
// Defines the graph state channels and initial state
// ============================================================================

import { AgentState, SuiteConfig, GeneratedTest, TestReview, TestResult } from '../types';

/**
 * Creates the initial state for the LangGraph workflow.
 */
export function createInitialState(projectPath: string, config: SuiteConfig): AgentState {
  return {
    projectPath,
    config,
    projectStructure: undefined,
    codeAnalysis: undefined,
    testStrategy: undefined,
    generatedTests: [],
    testReviews: [],
    testResults: [],
    securityReport: undefined,
    report: undefined,
    currentAgent: 'scanner',
    agentLog: [],
    errors: [],
    status: 'idle',
  };
}

/**
 * Merges partial state updates into the current state.
 * LangGraph uses this pattern for state channel updates.
 */
export function mergeState(current: AgentState, updates: Partial<AgentState>): AgentState {
  return {
    ...current,
    ...updates,
    // Merge arrays instead of replacing
    generatedTests: updates.generatedTests ?? current.generatedTests,
    testReviews: updates.testReviews ?? current.testReviews,
    testResults: updates.testResults ?? current.testResults,
    agentLog: updates.agentLog ?? current.agentLog,
    errors: updates.errors ?? current.errors,
  };
}

/**
 * State channel definitions for LangGraph.
 * Each channel defines how state updates are merged.
 */
export const stateChannels = {
  projectPath: { value: (a: string, b: string) => b || a, default: () => '' },
  config: { value: (a: SuiteConfig, b: SuiteConfig) => b || a },
  projectStructure: { value: (a: any, b: any) => b ?? a, default: () => undefined },
  codeAnalysis: { value: (a: any, b: any) => b ?? a, default: () => undefined },
  testStrategy: { value: (a: any, b: any) => b ?? a, default: () => undefined },
  generatedTests: {
    value: (a: GeneratedTest[], b: GeneratedTest[]) => b.length > 0 ? b : a,
    default: () => [] as GeneratedTest[],
  },
  testReviews: {
    value: (a: TestReview[], b: TestReview[]) => b.length > 0 ? b : a,
    default: () => [] as TestReview[],
  },
  testResults: {
    value: (a: TestResult[], b: TestResult[]) => b.length > 0 ? b : a,
    default: () => [] as TestResult[],
  },
  securityReport: { value: (a: any, b: any) => b ?? a, default: () => undefined },
  report: { value: (a: any, b: any) => b ?? a, default: () => undefined },
  currentAgent: { value: (a: string, b: string) => b || a, default: () => 'scanner' },
  agentLog: {
    value: (a: any[], b: any[]) => [...a, ...(b || [])],
    default: () => [],
  },
  errors: {
    value: (a: string[], b: string[]) => [...a, ...(b || [])],
    default: () => [] as string[],
  },
  status: { value: (a: string, b: string) => b || a, default: () => 'idle' },
};