/**
 * Live pathconf: union and read-only mirror paths affect _PC_NO_TRUNC / _PC_CHOWN_RESTRICTED.
 */
import { readFile } from 'node:fs/promises'
import path from 'node:path'
import { fileURLToPath } from 'node:url'
import test from 'brittle'
import b4a from 'b4a'

const __dirname = path.dirname(fileURLToPath(import.meta.url))

const AsyncFunction = Object.getPrototypeOf(async function () {}).constructor

async function loadBin(name) {
  const runtime = await readFile(
    path.join(__dirname, '../lib/runtime.js'),
    'utf8'
  )
  const body = await readFile(
    path.join(__dirname, `../src/${name}.js`),
    'utf8'
  )
  return new AsyncFunction(
    'ctx',
    'argv',
    `${runtime}\n${body}\nif (typeof run === 'function') return await run(ctx, argv)\n`
  )
}

function bareOsPathconfFromIndexLogic(shellEnv, vfs) {
  return (pathArg, name) => {
    const k = String(name || '').trim()
    const p = vfs.resolveLogical(String(pathArg || '/').trim() || '/')
    const rawUnion = String(shellEnv.BARE_OS_VFS_UNION_PREFIXES || '')
    const underUnion = rawUnion
      .split(',')
      .map((s) => s.trim())
      .filter((x) => x.startsWith('/'))
      .some((pre) => p === pre || p.startsWith(pre + '/'))
    const underMirror = p === '/mirror' || p.startsWith('/mirror/')
    const acctOn =
      shellEnv.BARE_OS_PERSONAL_ACCT_PREFIX === '1' ||
      shellEnv.BARE_OS_PERSONAL_ACCT_PREFIX === 'true'
    const underPersonalAcct =
      acctOn &&
      (p === '/.bare-os/acct' || p.startsWith('/.bare-os/acct/'))
    const table = {
      _PC_NAME_MAX: 255,
      _PC_NO_TRUNC: 1,
      _PC_CHOWN_RESTRICTED: 1
    }
    if (k === '_PC_CHOWN_RESTRICTED') {
      if (underMirror) return 0
      return 1
    }
    if (k === '_PC_NO_TRUNC' && (underMirror || (underUnion && !underPersonalAcct)))
      return 0
    if (table[k] === undefined) throw new Error('unknown: ' + k)
    return table[k]
  }
}

test('getconf pathconf _PC_NO_TRUNC is 0 under union prefix', async (t) => {
  const run = await loadBin('getconf')
  const logs = []
  const shellEnv = {
    BARE_OS_VFS_UNION_PREFIXES: '/system'
  }
  const vfs = {
    resolveLogical(p) {
      return String(p || '/')
    }
  }
  const ctx = {
    b4a,
    exitCode: 0,
    env: shellEnv,
    vfs,
    bareOsPathconf: bareOsPathconfFromIndexLogic(shellEnv, vfs),
    console: {
      log(s) {
        logs.push(String(s))
      },
      error(s) {
        logs.push(String(s))
      }
    }
  }
  await run(ctx, ['getconf', '_PC_NO_TRUNC', '/system/bin/foo'])
  t.is(ctx.exitCode, 0)
  t.is(logs.pop(), '0')
})

test('getconf pathconf _PC_CHOWN_RESTRICTED is 0 on mirror tree', async (t) => {
  const run = await loadBin('getconf')
  const logs = []
  const shellEnv = {}
  const vfs = {
    resolveLogical(p) {
      return String(p || '/')
    }
  }
  const ctx = {
    b4a,
    exitCode: 0,
    env: shellEnv,
    vfs,
    bareOsPathconf: bareOsPathconfFromIndexLogic(shellEnv, vfs),
    console: {
      log(s) {
        logs.push(String(s))
      },
      error(s) {
        logs.push(String(s))
      }
    }
  }
  await run(ctx, ['getconf', '_PC_CHOWN_RESTRICTED', '/mirror/aux0/x'])
  t.is(ctx.exitCode, 0)
  t.is(logs.pop(), '0')
})

test('getconf _SC_NPROCESSORS_ONLN delegates to bareOsGetconfSysconf', async (t) => {
  const run = await loadBin('getconf')
  const logs = []
  const ctx = {
    b4a,
    exitCode: 0,
    env: { BARE_OS_NPROC: '8' },
    console: {
      log(s) {
        logs.push(String(s))
      },
      error(s) {
        logs.push(String(s))
      }
    },
    bareOsGetconfSysconf(name) {
      if (name === '_SC_NPROCESSORS_ONLN') return '8'
      return null
    }
  }
  await run(ctx, ['getconf', '_SC_NPROCESSORS_ONLN'])
  t.is(ctx.exitCode, 0)
  t.is(logs[0], '8')
})

test('getconf _SC_BARE_OS_PIPELINE_MAX_BYTES uses bareOsGetconfSysconf', async (t) => {
  const run = await loadBin('getconf')
  const logs = []
  const ctx = {
    b4a,
    exitCode: 0,
    env: {},
    console: {
      log(s) {
        logs.push(String(s))
      },
      error(s) {
        logs.push(String(s))
      }
    },
    bareOsGetconfSysconf(name) {
      if (name === '_SC_BARE_OS_PIPELINE_MAX_BYTES') return '999999'
      return null
    }
  }
  await run(ctx, ['getconf', '_SC_BARE_OS_PIPELINE_MAX_BYTES'])
  t.is(ctx.exitCode, 0)
  t.is(logs[0], '999999')
})

test('pathconf _PC_NO_TRUNC stays 1 under union when personal acct prefix path', async (t) => {
  const run = await loadBin('getconf')
  const logs = []
  const shellEnv = {
    BARE_OS_VFS_UNION_PREFIXES: '/.bare-os',
    BARE_OS_PERSONAL_ACCT_PREFIX: '1'
  }
  const vfs = {
    resolveLogical(p) {
      return String(p || '/')
    }
  }
  const ctx = {
    b4a,
    exitCode: 0,
    env: shellEnv,
    vfs,
    bareOsPathconf: bareOsPathconfFromIndexLogic(shellEnv, vfs),
    console: {
      log(s) {
        logs.push(String(s))
      },
      error(s) {
        logs.push(String(s))
      }
    }
  }
  await run(ctx, ['getconf', '_PC_NO_TRUNC', '/.bare-os/acct/x/home'])
  t.is(ctx.exitCode, 0)
  t.is(logs.pop(), '1')
})