import { EventEmitter } from 'node:events'
import path from 'node:path'
import { eq } from 'drizzle-orm'
import { z } from 'zod'
import type { AppSettings, DeepPartial } from '@agent-server/shared'
import { config } from '../config'
import type { DB } from '../db'
import { settings as settingsTable } from '../db/schema'
import { badRequest } from '../lib/errors'
import { bundledClaudePath } from '../providers/claude/cli'
import { bundledCodexPath } from '../providers/codex/cli'

const KEY = 'app'

export function defaultSettings(): AppSettings {
  const shared = config.sharedDir
  return {
    paths: {
      workspaceRoot: path.join(config.dataDir, 'workspaces'),
      skillsDir: path.join(shared, 'skills'),
      pythonRuntime: path.join(shared, 'runtime/py'),
      nodeModules: path.join(shared, 'runtime/node/node_modules'),
      matplotlibrc: path.join(shared, 'runtime/matplotlibrc'),
    },
    security: { globalDeny: [], defaultFileAccessMode: 'restricted', corsOrigins: [] },
    network: { allowedDomains: ['pypi.org', 'files.pythonhosted.org'], blockPrivateFetch: true },
    limits: {
      concurrency: { global: 4, claude: 2, codex: 2 },
      interactionTimeoutSec: 600,
      uploadMaxMB: 50,
      workspaceMaxMB: 2048,
    },
    retention: { workspaceDays: 30 },
    teamLimits: { maxTasksPerJob: 20, maxLeadRunsPerJob: 30, maxCostUsdPerJob: null, maxMinutesPerJob: 120, maxConcurrentRuns: 4 },
    providers: {
      claude: {
        enabled: true,
        cliPath: bundledClaudePath() ?? path.join(config.home, '.local/bin/claude'),
        defaultModel: 'sonnet',
        models: ['sonnet', 'opus', 'haiku', 'fable'],
      },
      codex: {
        enabled: false,
        cliPath: bundledCodexPath() ?? path.join(config.home, '.local/bin/codex'),
        defaultModel: 'gpt-6.1-sol',
        models: [],
        configOverrides: [],
      },
    },
  }
}

const absPath = z.string().min(1).refine(p => path.isAbsolute(p), '必须是绝对路径')
const domain = z.string().regex(/^(\*\.)?[a-z0-9-]+(\.[a-z0-9-]+)+$/i, '域名格式不正确')

export const teamLimitsSchema = z.object({
  maxTasksPerJob: z.number().int().min(1).max(500),
  maxLeadRunsPerJob: z.number().int().min(1).max(1000),
  maxCostUsdPerJob: z.number().min(0.01).max(10000).nullable(),
  maxMinutesPerJob: z.number().int().min(1).max(7 * 24 * 60),
  maxConcurrentRuns: z.number().int().min(1).max(32),
})

const settingsSchema: z.ZodType<AppSettings> = z.object({
  paths: z.object({ workspaceRoot: absPath, skillsDir: absPath, pythonRuntime: absPath, nodeModules: absPath, matplotlibrc: absPath }),
  security: z.object({
    globalDeny: z.array(z.string().min(1)),
    defaultFileAccessMode: z.enum(['restricted', 'broad']),
    corsOrigins: z.array(z.string().regex(/^https?:\/\/[a-z0-9.-]+(:\d+)?$/i, '来源格式应为 https://host[:port]，不带路径')),
  }),
  network: z.object({ allowedDomains: z.array(domain), blockPrivateFetch: z.boolean() }),
  limits: z.object({
    concurrency: z.object({
      global: z.number().int().min(1).max(32),
      claude: z.number().int().min(0).max(32),
      codex: z.number().int().min(0).max(32),
    }),
    interactionTimeoutSec: z.number().int().min(30).max(86400),
    uploadMaxMB: z.number().int().min(1).max(1024),
    workspaceMaxMB: z.number().int().min(10).max(102400),
  }),
  retention: z.object({ workspaceDays: z.number().int().min(1).max(3650) }),
  teamLimits: teamLimitsSchema,
  providers: z.object({
    claude: z.object({ enabled: z.boolean(), cliPath: absPath, defaultModel: z.string().min(1), models: z.array(z.string().min(1)) }),
    codex: z.object({
      enabled: z.boolean(),
      cliPath: absPath,
      defaultModel: z.string(),
      models: z.array(z.string().min(1)),
      configOverrides: z.array(z.string().min(1)),
    }),
  }),
})

function deepMerge<T>(base: T, patch: unknown): T {
  if (patch === undefined) return base
  if (typeof base !== 'object' || base === null || Array.isArray(base) || typeof patch !== 'object' || patch === null || Array.isArray(patch)) {
    return patch as T
  }
  const out: Record<string, unknown> = { ...(base as Record<string, unknown>) }
  for (const [k, v] of Object.entries(patch)) out[k] = deepMerge(out[k], v)
  return out as T
}

export class SettingsService extends EventEmitter<{ changed: [AppSettings] }> {
  private cache: AppSettings

  constructor(private db: DB) {
    super()
    const row = db.select().from(settingsTable).where(eq(settingsTable.key, KEY)).get()
    // 存储的值与默认值合并，以便新版本增加的配置项自动获得默认值
    this.cache = deepMerge(defaultSettings(), row?.value)
  }

  get(): AppSettings {
    return this.cache
  }

  update(patch: DeepPartial<AppSettings>): AppSettings {
    const merged = deepMerge(this.cache, patch)
    const parsed = settingsSchema.safeParse(merged)
    if (!parsed.success) throw badRequest('配置校验失败', z.treeifyError(parsed.error))
    this.db.insert(settingsTable)
      .values({ key: KEY, value: parsed.data })
      .onConflictDoUpdate({ target: settingsTable.key, set: { value: parsed.data, updatedAt: new Date().toISOString() } })
      .run()
    this.cache = parsed.data
    this.emit('changed', this.cache)
    return this.cache
  }
}