import { ConvexHttpClient } from "convex/browser"
import { makeFunctionReference } from "convex/server"
import {
  EgressClient,
  EncodedFileOutput,
  EncodedFileType,
  S3Upload,
} from "livekit-server-sdk"
import { VOICE_ASSISTANT_SOURCE } from "@/lib/voice-assistant/types"

type VoiceRecordingStatus = "pending" | "starting" | "recording" | "completed" | "failed"

type CreateVoiceSessionArgs = {
  roomName: string
  participantIdentity: string
  siteUrl?: string
  pathname?: string
  pageUrl?: string
  source?: string
  metadata?: string
  startedAt?: number
  recordingDisclosureAt?: number
  recordingStatus?: VoiceRecordingStatus
}

type AddTranscriptTurnArgs = {
  sessionId: string
  roomName: string
  participantIdentity: string
  role: "user" | "assistant" | "system"
  text: string
  kind?: string
  isFinal?: boolean
  language?: string
  source?: string
  createdAt?: number
}

type UpdateVoiceRecordingArgs = {
  sessionId: string
  recordingStatus?: VoiceRecordingStatus
  recordingId?: string
  recordingUrl?: string
  recordingError?: string
}

type CompleteVoiceSessionArgs = UpdateVoiceRecordingArgs & {
  endedAt?: number
}

type VoiceRecordingConfig = {
  bucket: string
  egressClient: EgressClient
  endpoint: string
  forcePathStyle: boolean
  pathPrefix: string
  publicBaseUrl?: string
  region: string
  secret: string
  accessKey: string
}

type VoicePersistenceServices = {
  convexClient: ConvexHttpClient | null
  recording: VoiceRecordingConfig | null
}

const CREATE_VOICE_SESSION = makeFunctionReference<"mutation">("voiceSessions:createSession")
const ADD_VOICE_TRANSCRIPT_TURN = makeFunctionReference<"mutation">("voiceSessions:addTranscriptTurn")
const UPDATE_VOICE_RECORDING = makeFunctionReference<"mutation">("voiceSessions:updateRecording")
const COMPLETE_VOICE_SESSION = makeFunctionReference<"mutation">("voiceSessions:completeSession")

function readOptionalEnv(name: string) {
  const value = process.env[name]
  return typeof value === "string" && value.trim() ? value.trim() : ""
}

function readBooleanEnv(name: string) {
  const value = readOptionalEnv(name).toLowerCase()
  if (!value) {
    return undefined
  }

  return value === "1" || value === "true" || value === "yes"
}

function sanitizePathSegment(value: string) {
  return value
    .replace(/[^a-zA-Z0-9/_-]+/g, "-")
    .replace(/-+/g, "-")
    .replace(/\/+/g, "/")
    .replace(/^-|-$/g, "")
}

function buildRecordingFilepath(roomName: string) {
  const prefix = readOptionalEnv("VOICE_RECORDING_PATH_PREFIX") || "livekit-recordings"
  const date = new Date()
  const year = date.getUTCFullYear()
  const month = String(date.getUTCMonth() + 1).padStart(2, "0")
  const day = String(date.getUTCDate()).padStart(2, "0")
  const stamp = date.toISOString().replace(/[:.]/g, "-")
  const safeRoom = sanitizePathSegment(roomName)
  return `${sanitizePathSegment(prefix)}/${year}/${month}/${day}/${safeRoom}-${stamp}.mp3`
}

function buildRecordingUrl(publicBaseUrl: string | undefined, bucket: string, filepath: string) {
  const encodedPath = filepath
    .split("/")
    .map((segment) => encodeURIComponent(segment))
    .join("/")

  if (publicBaseUrl) {
    return `${publicBaseUrl.replace(/\/$/, "")}/${encodedPath}`
  }

  return `s3://${bucket}/${filepath}`
}

export function getVoicePersistenceServices(args: {
  livekitUrl: string
  livekitApiKey: string
  livekitApiSecret: string
}) {
  const convexUrl = readOptionalEnv("NEXT_PUBLIC_CONVEX_URL") || readOptionalEnv("CONVEX_URL")
  const convexClient = convexUrl ? new ConvexHttpClient(convexUrl) : null

  const accessKey =
    readOptionalEnv("VOICE_RECORDING_ACCESS_KEY_ID") ||
    readOptionalEnv("CLOUDFLARE_R2_ACCESS_KEY_ID") ||
    readOptionalEnv("AWS_ACCESS_KEY_ID") ||
    readOptionalEnv("AWS_ACCESS_KEY")
  const secret =
    readOptionalEnv("VOICE_RECORDING_SECRET_ACCESS_KEY") ||
    readOptionalEnv("CLOUDFLARE_R2_SECRET_ACCESS_KEY") ||
    readOptionalEnv("AWS_SECRET_ACCESS_KEY") ||
    readOptionalEnv("AWS_SECRET_KEY")
  const endpoint =
    readOptionalEnv("VOICE_RECORDING_ENDPOINT") ||
    readOptionalEnv("CLOUDFLARE_R2_ENDPOINT")
  const bucket = readOptionalEnv("VOICE_RECORDING_BUCKET")
  const region = readOptionalEnv("VOICE_RECORDING_REGION") || readOptionalEnv("AWS_DEFAULT_REGION") || "auto"
  const publicBaseUrl = readOptionalEnv("VOICE_RECORDING_PUBLIC_BASE_URL") || undefined
  const forcePathStyle = readBooleanEnv("VOICE_RECORDING_FORCE_PATH_STYLE") ?? true
  const requested = readBooleanEnv("VOICE_RECORDING_ENABLED")
  const hasRecordingEnv = Boolean(accessKey && secret && endpoint && bucket)
  const recordingEnabled = requested ?? hasRecordingEnv

  const recording =
    recordingEnabled && hasRecordingEnv
      ? {
          accessKey,
          bucket,
          egressClient: new EgressClient(args.livekitUrl, args.livekitApiKey, args.livekitApiSecret),
          endpoint,
          forcePathStyle,
          pathPrefix: readOptionalEnv("VOICE_RECORDING_PATH_PREFIX") || "livekit-recordings",
          publicBaseUrl,
          region,
          secret,
        }
      : null

  return {
    convexClient,
    recording,
  } satisfies VoicePersistenceServices
}

async function safeMutation<TArgs extends object>(
  client: ConvexHttpClient | null,
  reference: ReturnType<typeof makeFunctionReference<"mutation">>,
  args: TArgs,
) {
  if (!client) {
    return null
  }

  return await client.mutation(reference, args)
}

export async function createVoiceSessionRecord(
  services: VoicePersistenceServices,
  args: CreateVoiceSessionArgs,
) {
  return await safeMutation(services.convexClient, CREATE_VOICE_SESSION, {
    ...args,
    source: args.source || VOICE_ASSISTANT_SOURCE,
  })
}

export async function addVoiceTranscriptTurn(
  services: VoicePersistenceServices,
  args: AddTranscriptTurnArgs,
) {
  const text = args.text.replace(/\s+/g, " ").trim()
  if (!text) {
    return null
  }

  return await safeMutation(services.convexClient, ADD_VOICE_TRANSCRIPT_TURN, {
    ...args,
    source: args.source || VOICE_ASSISTANT_SOURCE,
    text,
  })
}

export async function updateVoiceRecording(
  services: VoicePersistenceServices,
  args: UpdateVoiceRecordingArgs,
) {
  return await safeMutation(services.convexClient, UPDATE_VOICE_RECORDING, args)
}

export async function completeVoiceSession(
  services: VoicePersistenceServices,
  args: CompleteVoiceSessionArgs,
) {
  return await safeMutation(services.convexClient, COMPLETE_VOICE_SESSION, args)
}

export async function startVoiceRecording(
  services: VoicePersistenceServices,
  roomName: string,
) {
  if (!services.recording) {
    return null
  }

  const filepath = buildRecordingFilepath(roomName)
  const output = new EncodedFileOutput({
    fileType: EncodedFileType.MP3,
    filepath,
    output: {
      case: "s3",
      value: new S3Upload({
        accessKey: services.recording.accessKey,
        secret: services.recording.secret,
        region: services.recording.region,
        endpoint: services.recording.endpoint,
        bucket: services.recording.bucket,
        forcePathStyle: services.recording.forcePathStyle,
      }),
    },
  })

  const info = await services.recording.egressClient.startRoomCompositeEgress(roomName, output, {
    audioOnly: true,
  })

  return {
    recordingId: info.egressId,
    recordingStatus: "recording" as const,
    recordingUrl: buildRecordingUrl(services.recording.publicBaseUrl, services.recording.bucket, filepath),
  }
}

export async function stopVoiceRecording(
  services: VoicePersistenceServices,
  recordingId: string | null | undefined,
) {
  if (!services.recording || !recordingId) {
    return null
  }

  return await services.recording.egressClient.stopEgress(recordingId)
}