import * as fs from "node:fs";
import * as path from "node:path";
import { CIAgentConfig, DEFAULT_CIAGENT_CONFIG } from "../types/config.js";

const CI_DIR = ".ciagent";
const CONFIG_FILE = "config.json";

export function getCIAgentConfigPath(projectPath: string): string {
  return path.join(projectPath, CI_DIR, CONFIG_FILE);
}

export function getCIDir(projectPath: string): string {
  return path.join(projectPath, CI_DIR);
}

export function ensureCIDir(projectPath: string): void {
  const ciDir = getCIDir(projectPath);
  if (!fs.existsSync(ciDir)) {
    fs.mkdirSync(ciDir, { recursive: true });
  }
}

function deepMerge(base: CIAgentConfig, override: Record<string, unknown>): CIAgentConfig {
  const result = { ...base } as Record<string, unknown>;
  for (const key of Object.keys(override)) {
    const baseVal = result[key];
    const overrideVal = override[key];
    if (
      baseVal && typeof baseVal === "object" && !Array.isArray(baseVal) &&
      overrideVal && typeof overrideVal === "object" && !Array.isArray(overrideVal)
    ) {
      result[key] = deepMerge(
        baseVal as unknown as CIAgentConfig,
        overrideVal as Record<string, unknown>
      ) as unknown;
    } else if (overrideVal !== undefined) {
      result[key] = overrideVal;
    }
  }
  return result as unknown as CIAgentConfig;
}

export function loadConfig(projectPath: string): CIAgentConfig {
  const configPath = getCIAgentConfigPath(projectPath);
  if (!fs.existsSync(configPath)) {
    return { ...DEFAULT_CIAGENT_CONFIG };
  }
  const raw = fs.readFileSync(configPath, "utf-8");
  const parsed = JSON.parse(raw);
  return deepMerge(DEFAULT_CIAGENT_CONFIG, parsed);
}

export function saveConfig(projectPath: string, config: CIAgentConfig): void {
  ensureCIDir(projectPath);
  const configPath = getCIAgentConfigPath(projectPath);
  fs.writeFileSync(configPath, JSON.stringify(config, null, 2), "utf-8");
}

export function isCIAgentInitialized(projectPath: string): boolean {
  const ciDir = getCIDir(projectPath);
  const configPath = getCIAgentConfigPath(projectPath);
  return fs.existsSync(ciDir) && fs.existsSync(configPath);
}

export function initCIAgent(projectPath: string, config?: Partial<CIAgentConfig>, projectSlug?: string, projectName?: string): CIAgentConfig {
  ensureCIDir(projectPath);

  let projects = config?.projects || DEFAULT_CIAGENT_CONFIG.projects;
  let activeProject = config?.active_project || DEFAULT_CIAGENT_CONFIG.active_project;

  if (projectSlug) {
    if (!projects.some((p) => p.slug === projectSlug)) {
      projects = [...projects, { slug: projectSlug, name: projectName || projectSlug, default: projects.length === 0 }];
    }
    activeProject = projectSlug;
  }

  const fullConfig: CIAgentConfig = {
    ...DEFAULT_CIAGENT_CONFIG,
    ...config,
    projects,
    active_project: activeProject,
    autonomy: { ...DEFAULT_CIAGENT_CONFIG.autonomy, ...config?.autonomy },
    parallelization: {
      ...DEFAULT_CIAGENT_CONFIG.parallelization,
      ...config?.parallelization,
    },
    verification: { ...DEFAULT_CIAGENT_CONFIG.verification, ...config?.verification },
    security: { ...DEFAULT_CIAGENT_CONFIG.security, ...config?.security },
    git: { ...DEFAULT_CIAGENT_CONFIG.git, ...config?.git },
    backend: { ...DEFAULT_CIAGENT_CONFIG.backend, ...config?.backend },
  };
  saveConfig(projectPath, fullConfig);
  return fullConfig;
}