// ========= Copyright 2026 @ Strukto.AI All Rights Reserved. =========
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ========= Copyright 2026 @ Strukto.AI All Rights Reserved. =========

import {
  IOResult,
  ResourceName,
  command,
  specOf,
  type ByteSource,
  type CommandFnResult,
  type CommandOpts,
  type PathSpec,
  type RAMAccessor,
} from '@struktoai/mirage-core'
import { transcribe } from '../utils.ts'
import { readRam } from './read.ts'

const ENC = new TextEncoder()

function headOggCommand(
  accessor: RAMAccessor,
  paths: PathSpec[],
  _texts: string[],
  opts: CommandOpts,
): CommandFnResult {
  if (paths.length === 0) {
    return [null, new IOResult({ exitCode: 1, stderr: ENC.encode('head: missing operand\n') })]
  }
  const first = paths[0]
  if (first === undefined) return [null, new IOResult()]
  if (typeof opts.flags.c === 'string') {
    return [
      null,
      new IOResult({ exitCode: 1, stderr: ENC.encode('head: -c not supported for audio files\n') }),
    ]
  }
  const n = typeof opts.flags.n === 'string' ? Number.parseInt(opts.flags.n, 10) : 10
  try {
    const raw = readRam(accessor, first)
    const out: ByteSource = transcribe(raw, undefined, n)
    return [out, new IOResult({ reads: { [first.original]: raw }, cache: [first.original] })]
  } catch (err) {
    const msg = err instanceof Error ? err.message : String(err)
    return [
      null,
      new IOResult({
        exitCode: 1,
        stderr: ENC.encode(`head: ${first.original}: failed to read as ogg: ${msg}\n`),
      }),
    ]
  }
}

export const RAM_LOCAL_AUDIO_HEAD_OGG = command({
  name: 'head',
  resource: ResourceName.RAM,
  spec: specOf('head'),
  filetype: '.ogg',
  fn: headOggCommand,
})
