import type { NextRequest } from "next/server";
import type { GenerationInput, GenerationOutput, ModelCapability } from "@/lib/providers/types";
import {
  buildPopiserverForwardHeaders,
  fetchPopiModelDetail,
  getPopiserverBaseUrl,
  type PopiAIModel,
} from "@/app/api/_popiserverModels";
import { ApiError } from "@/app/api/_errors";
import { logGatewayRequest, logGatewayResponse } from "@/app/api/_gatewayLogging";

const POPISERVER_TASK_CREATE_PATH = "/api_client/anime/task/create";
const POPISERVER_TASK_LIST_PATH = "/api_client/anime/task/list";
const POPISERVER_MEDIA_UPLOAD_PATH = "/api_client/media/upload";

const POPISERVER_IMAGE_DYNAMIC_KEYS = [
  "image",
  "images",
  "image_url",
  "image_urls",
  "first_frame",
  "first_frame_url",
  "last_frame",
  "last_frame_url",
  "reference_image",
  "reference_image_url",
  "reference_image_urls",
];

const POPISERVER_VIDEO_DYNAMIC_KEYS = [
  "video",
  "videos",
  "video_url",
  "video_urls",
];

const POPISERVER_AUDIO_DYNAMIC_KEYS = [
  "audio",
  "audios",
  "audio_url",
  "audio_urls",
];

const POPISERVER_VOICE_DYNAMIC_KEYS = [
  "voiceId",
  "voice_id",
];

const POPISERVER_MEDIA_DYNAMIC_KEYS = [
  ...POPISERVER_IMAGE_DYNAMIC_KEYS,
  ...POPISERVER_VIDEO_DYNAMIC_KEYS,
  ...POPISERVER_AUDIO_DYNAMIC_KEYS,
];

type PopiserverResponse<T> = {
  status?: string;
  message?: string;
  data?: T;
};

type PopiTaskCreateData = {
  id?: number | string;
  taskId?: number | string;
};

type PopiTaskListData = {
  list?: PopiTask[];
};

type PopiUploadedMedia = {
  url?: string;
  path?: string;
  originUrl?: string;
  originPath?: string;
};

type PopiMediaUploadData =
  | PopiUploadedMedia
  | PopiUploadedMedia[]
  | {
      list?: PopiUploadedMedia[];
      files?: PopiUploadedMedia[];
      urls?: string[];
    };

type PopiTaskResult = {
  images?: string[] | null;
  video?: string | null;
  voice?: string | null;
  cover?: string | null;
};

type PopiTask = {
  id?: number | string;
  type?: number;
  subType?: number;
  status?: number;
  errorMsg?: string;
  userErrorTipMsg?: string;
  images?: string[] | null;
  voice?: string | null;
  resultList?: PopiTaskResult[] | null;
};

export type PopiTaskPollResult =
  | { status: "processing" }
  | { status: "failed"; error: string }
  | { status: "completed"; output: GenerationOutput };

function asString(value: unknown): string | null {
  return typeof value === "string" && value.length > 0 ? value : null;
}

function asNumber(value: unknown): number | null {
  if (typeof value === "number" && Number.isFinite(value)) return value;
  if (typeof value === "string" && value.trim().length > 0) {
    const parsed = Number(value);
    return Number.isFinite(parsed) ? parsed : null;
  }
  return null;
}

function firstString(values: unknown[]): string | null {
  for (const value of values) {
    if (typeof value === "string" && value.length > 0) return value;
    if (Array.isArray(value)) {
      const found = firstString(value);
      if (found) return found;
    }
  }
  return null;
}

function collectStrings(values: unknown[]): string[] {
  const items: string[] = [];
  for (const value of values) {
    if (typeof value === "string" && value.length > 0) {
      items.push(value);
      continue;
    }
    if (Array.isArray(value)) {
      items.push(...collectStrings(value));
    }
  }
  return items;
}

function stringArray(value: string | string[] | undefined): string[] {
  if (typeof value === "string") return value.length > 0 ? [value] : [];
  if (Array.isArray(value)) return value.filter((item) => typeof item === "string" && item.length > 0);
  return [];
}

function firstDynamicString(
  dynamicInputs: Record<string, string | string[]> | undefined,
  keys: string[]
): string | null {
  if (!dynamicInputs) return null;
  for (const key of keys) {
    const value = dynamicInputs[key];
    const found = firstString(Array.isArray(value) ? value : [value]);
    if (found) return found;
  }
  return null;
}

function collectDynamicMedia(
  dynamicInputs: Record<string, string | string[]> | undefined,
  keys: string[]
): string[] {
  if (!dynamicInputs) return [];
  const items: string[] = [];
  for (const key of keys) {
    items.push(...stringArray(dynamicInputs[key]));
  }
  return items;
}

function mediaResourceUrl(media: PopiUploadedMedia): string | null {
  return media.url || media.originUrl || media.path || media.originPath || null;
}

function isUploadedMedia(value: PopiMediaUploadData): value is PopiUploadedMedia {
  return (
    "url" in value ||
    "originUrl" in value ||
    "path" in value ||
    "originPath" in value
  );
}

function isUploadableMedia(value: string): boolean {
  return value.startsWith("data:");
}

function parseDataUrl(value: string): { mimeType: string; base64: string } | null {
  const match = value.match(/^data:([^;,]+)?(?:;[^,]*)?;base64,(.*)$/);
  if (!match) return null;
  return {
    mimeType: match[1] || "application/octet-stream",
    base64: match[2],
  };
}

function extensionForMimeType(mimeType: string): string {
  const normalized = mimeType.toLowerCase();
  if (normalized === "image/jpeg") return "jpg";
  if (normalized === "image/png") return "png";
  if (normalized === "image/webp") return "webp";
  if (normalized === "image/gif") return "gif";
  if (normalized === "video/mp4") return "mp4";
  if (normalized === "video/webm") return "webm";
  if (normalized === "audio/mpeg" || normalized === "audio/mp3") return "mp3";
  if (normalized === "audio/wav" || normalized === "audio/x-wav") return "wav";
  return normalized.split("/")[1]?.replace(/[^a-z0-9]/g, "") || "bin";
}

function dataUrlToFile(value: string, index: number): File {
  const dataUrl = parseDataUrl(value);
  if (!dataUrl) {
    throw ApiError.badRequest("Only base64 data URLs can be uploaded to PopiServer media.");
  }
  const binary = Buffer.from(dataUrl.base64, "base64");
  const extension = extensionForMimeType(dataUrl.mimeType);
  return new File([binary], `canvas-input-${Date.now()}-${index}.${extension}`, {
    type: dataUrl.mimeType,
  });
}

function uploadedMediaUrls(data: PopiMediaUploadData | undefined): string[] {
  if (!data) return [];
  if (Array.isArray(data)) {
    return data.map(mediaResourceUrl).filter((url): url is string => Boolean(url));
  }
  if ("urls" in data && Array.isArray(data.urls)) {
    return data.urls.filter((url): url is string => typeof url === "string" && url.length > 0);
  }
  const list = ("list" in data && Array.isArray(data.list))
    ? data.list
    : ("files" in data && Array.isArray(data.files))
      ? data.files
      : null;
  if (list) {
    return list.map(mediaResourceUrl).filter((url): url is string => Boolean(url));
  }
  const single = isUploadedMedia(data) ? mediaResourceUrl(data) : null;
  return single ? [single] : [];
}

async function uploadPopiMediaBatch(
  request: NextRequest,
  token: string,
  media: string[]
): Promise<string[]> {
  const uploadablePositions = media
    .map((item, index) => ({ item, index }))
    .filter(({ item }) => isUploadableMedia(item));
  const uniqueUploadable = [...new Set(uploadablePositions.map(({ item }) => item))];
  if (uniqueUploadable.length === 0) return media;

  const formData = new FormData();
  formData.append("multiple", "true");
  uniqueUploadable.forEach((item, index) => {
    formData.append("file", dataUrlToFile(item, index));
  });

  const url = new URL(getPopiserverBaseUrl(request) + POPISERVER_MEDIA_UPLOAD_PATH);
  url.searchParams.set("multiple", "true");
  const init: RequestInit = {
    method: "POST",
    headers: buildPopiserverForwardHeaders(request, token),
    body: formData,
    cache: "no-store",
  };
  const context = {
    popiPath: POPISERVER_MEDIA_UPLOAD_PATH,
    mediaCount: uniqueUploadable.length,
  };
  const startedAt = Date.now();
  logGatewayRequest("Uploading PopiServer task media", url.toString(), init, context);
  const response = await fetch(url, init);
  await logGatewayResponse("PopiServer task media upload response", url.toString(), init, response, context, startedAt);
  const body = (await response.json().catch(() => null)) as PopiserverResponse<PopiMediaUploadData> | null;
  if (!response.ok) {
    throw ApiError.provider(body?.message || "PopiServer media upload failed.", response.status);
  }
  if (!body || body.status !== "0000") {
    throw ApiError.provider(body?.message || "PopiServer media upload returned an error.");
  }

  const uploadedUrls = uploadedMediaUrls(body.data);
  if (uploadedUrls.length !== uniqueUploadable.length) {
    throw ApiError.provider("PopiServer media upload response count does not match request count.");
  }

  const uploadedBySource = new Map<string, string>();
  uniqueUploadable.forEach((item, index) => {
    uploadedBySource.set(item, uploadedUrls[index]);
  });

  const result = [...media];
  uploadablePositions.forEach(({ item, index }) => {
    result[index] = uploadedBySource.get(item) || item;
  });
  return result;
}

async function preparePopiTaskMedia(
  request: NextRequest,
  token: string,
  input: GenerationInput
): Promise<GenerationInput> {
  const dynamicInputs = input.dynamicInputs
    ? { ...input.dynamicInputs }
    : undefined;
  const mediaValues: string[] = [];
  const assignments: Array<(uploaded: string) => void> = [];

  const collect = (value: string, assign: (uploaded: string) => void): void => {
    mediaValues.push(value);
    assignments.push(assign);
  };

  const images = input.images ? [...input.images] : undefined;
  images?.forEach((value, index) => {
    collect(value, (uploaded) => {
      images[index] = uploaded;
    });
  });

  if (dynamicInputs) {
    for (const key of POPISERVER_MEDIA_DYNAMIC_KEYS) {
      const value = dynamicInputs[key];
      if (typeof value === "string") {
        collect(value, (uploaded) => {
          dynamicInputs[key] = uploaded;
        });
      } else if (Array.isArray(value)) {
        const values = [...value];
        values.forEach((item, index) => {
          collect(item, (uploaded) => {
            values[index] = uploaded;
            dynamicInputs[key] = values;
          });
        });
      }
    }
  }

  const uploadedValues = mediaValues.length > 0
    ? await uploadPopiMediaBatch(request, token, mediaValues)
    : [];
  uploadedValues.forEach((uploaded, index) => assignments[index]?.(uploaded));

  return { ...input, images, dynamicInputs };
}

function getCapabilityMediaType(capabilities: ModelCapability[]): "image" | "video" | "audio" {
  if (capabilities.some((capability) => capability.includes("audio"))) return "audio";
  if (capabilities.some((capability) => capability.includes("video"))) return "video";
  return "image";
}

function inferTaskType(input: GenerationInput): number {
  const metadataType = asNumber(input.model.metadata?.type);
  if (metadataType) return metadataType;
  const mediaType = getCapabilityMediaType(input.model.capabilities);
  if (mediaType === "video") return 2;
  if (mediaType === "audio") return 3;
  return 1;
}

function inferTaskSubType(input: GenerationInput, type: number): number {
  const metadataSubType = asNumber(input.model.metadata?.subType);
  if (metadataSubType) return metadataSubType;
  const metadataSubTypes = input.model.metadata?.subTypes;
  if (Array.isArray(metadataSubTypes)) {
    const first = metadataSubTypes.map(asNumber).find((value): value is number => value !== null);
    if (first) return first;
  }

  if (type === 3) return 301;
  if (type === 2) {
    return 203;
  }
  return (input.images?.length ?? 0) > 0 ? 103 : 102;
}

function resolveAspectRatio(parameters: Record<string, unknown> | undefined): string {
  return asString(parameters?.ratio) ?? "16:9";
}

function dimensionsForAspectRatio(aspectRatio: string): { width: number; height: number } {
  if (aspectRatio === "9:16") return { width: 720, height: 1280 };
  if (aspectRatio === "1:1") return { width: 1024, height: 1024 };
  return { width: 1280, height: 720 };
}

function buildPopiTaskBody(input: GenerationInput, modelDetail: PopiAIModel | null): Record<string, unknown> {
  const parameters = input.parameters || {};
  const type = asNumber(parameters.type) ?? inferTaskType(input);
  const subType = asNumber(parameters.subType) ?? inferTaskSubType(input, type);
  const aspectRatio = resolveAspectRatio(parameters);
  const dimensions = dimensionsForAspectRatio(aspectRatio);
  const modelCode =
    asString(input.model.metadata?.aiModelCode) ??
    modelDetail?.code ??
    input.model.id;
  const modelAlias =
    asString(input.model.metadata?.aiModelCodeAlias) ??
    modelDetail?.aiModelCodeAlias ??
    modelCode;
  const aiModelId =
    asNumber(input.model.metadata?.aiModelId) ??
    asNumber(input.model.id) ??
    modelDetail?.id;
  const images = [
    ...(input.images || []),
    ...collectDynamicMedia(input.dynamicInputs, POPISERVER_IMAGE_DYNAMIC_KEYS),
  ];
  const videos = collectDynamicMedia(input.dynamicInputs, POPISERVER_VIDEO_DYNAMIC_KEYS);
  const audios = collectDynamicMedia(input.dynamicInputs, POPISERVER_AUDIO_DYNAMIC_KEYS);
  const voiceId =
    firstDynamicString(input.dynamicInputs, POPISERVER_VOICE_DYNAMIC_KEYS) ??
    asString(parameters.voiceId) ??
    "";

  const commonBody = {
    type,
    chatPrompt: input.prompt,
    model: modelAlias,
    origin: "canvas",
    aiPlatform: "GATEWAY",
    aiModelId,
    aiModelCode: modelCode,
    aiModelCodeAlias: modelAlias,
    subType,
    batchSize: asNumber(parameters.batchSize) ?? 1,
  };

  if (type === 3) {
    return {
      ...parameters,
      ...commonBody,
      ...(audios.length > 0 ? { audios: [...new Set(audios)] } : {}),
      ...(voiceId ? { voiceId } : {}),
    };
  }

  return {
    ...parameters,
    ...commonBody,
    ...(images.length > 0 ? { images: [...new Set(images)] } : {}),
    ...(videos.length > 0 ? { videos: [...new Set(videos)] } : {}),
    ...(audios.length > 0 ? { audios: [...new Set(audios)] } : {}),
    styleId: asNumber(parameters.styleId) ?? 0,
    width: asNumber(parameters.width) ?? dimensions.width,
    height: asNumber(parameters.height) ?? dimensions.height,
    aspectRatio,
    duration: asNumber(parameters.duration) ?? undefined,
    resolution: asString(parameters.resolution) ?? "720p",
  };
}

async function fetchPopiJson<T>(
  request: NextRequest,
  token: string,
  path: string,
  init: RequestInit
): Promise<T> {
  const url = getPopiserverBaseUrl(request) + path;
  const requestInit: RequestInit = {
    ...init,
    headers: {
      ...buildPopiserverForwardHeaders(request, token),
      ...(init.headers || {}),
    },
    cache: "no-store",
  };
  const context = {
    popiPath: path,
  };
  const startedAt = Date.now();
  logGatewayRequest("Calling PopiServer task API", url, requestInit, context);
  const response = await fetch(url, requestInit);
  await logGatewayResponse("PopiServer task API response", url, requestInit, response, context, startedAt);
  const body = (await response.json().catch(() => null)) as PopiserverResponse<T> | null;
  if (!response.ok) {
    throw ApiError.provider(body?.message || "PopiServer task API request failed.", response.status);
  }
  if (!body || body.status !== "0000") {
    throw ApiError.provider(body?.message || "PopiServer task API returned an error.");
  }
  return body.data as T;
}

export async function submitPopiTask(
  request: NextRequest,
  token: string,
  input: GenerationInput
): Promise<{ taskId: string }> {
  let modelDetail: PopiAIModel | null = null;
  if (!input.model.metadata?.aiModelCode && !input.model.metadata?.aiModelCodeAlias) {
    modelDetail = await fetchPopiModelDetail(request, token, input.model.id).catch(() => null);
  }
  const preparedInput = await preparePopiTaskMedia(request, token, input);
  const body = buildPopiTaskBody(preparedInput, modelDetail);
  const data = await fetchPopiJson<PopiTaskCreateData>(request, token, POPISERVER_TASK_CREATE_PATH, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify(body),
  });
  const taskId = asString(data?.id) ?? asString(data?.taskId) ?? String(data?.id ?? data?.taskId ?? "");
  if (!taskId) {
    throw ApiError.provider("PopiServer task create response did not include a task id.");
  }
  return { taskId };
}

function extractOutputFromTask(task: PopiTask, mediaType: string): GenerationOutput {
  const firstResult = Array.isArray(task.resultList) ? task.resultList[0] : null;
  if (mediaType === "video") {
    const url = firstResult?.video || firstResult?.cover || firstString(task.images || []) || null;
    return url
      ? { success: true, outputs: [{ type: "video", data: "", url }] }
      : { success: false, error: "PopiServer video task completed without output" };
  }
  if (mediaType === "audio") {
    const url = firstResult?.voice || task.voice || null;
    return url
      ? { success: true, outputs: [{ type: "audio", data: "", url }] }
      : { success: false, error: "PopiServer audio task completed without output" };
  }
  const images = [
    ...new Set(collectStrings([
      ...(Array.isArray(task.resultList) ? task.resultList.map((result) => result.images) : []),
      task.images,
    ])),
  ];
  return images.length > 0
    ? { success: true, outputs: images.map((url) => ({ type: "image", data: "", url })) }
    : { success: false, error: "PopiServer image task completed without output" };
}

export async function checkPopiTaskOnce(
  request: NextRequest,
  token: string,
  taskId: string,
  mediaType: string
): Promise<PopiTaskPollResult> {
  const url = new URL(getPopiserverBaseUrl(request) + POPISERVER_TASK_LIST_PATH);
  url.searchParams.set("ids", taskId);
  url.searchParams.set("origin", "canvas");
  const init: RequestInit = {
    method: "GET",
    headers: buildPopiserverForwardHeaders(request, token),
    cache: "no-store",
  };
  const context = {
    mediaType,
    popiPath: POPISERVER_TASK_LIST_PATH,
  };
  const startedAt = Date.now();
  logGatewayRequest("Polling PopiServer task API", url.toString(), init, context);
  const response = await fetch(url, init);
  await logGatewayResponse("PopiServer task poll response", url.toString(), init, response, context, startedAt);
  const body = (await response.json().catch(() => null)) as PopiserverResponse<PopiTaskListData> | null;
  if (!response.ok) {
    throw ApiError.provider(body?.message || "Failed to poll PopiServer task.", response.status);
  }
  if (!body || body.status !== "0000") {
    throw ApiError.provider(body?.message || "PopiServer task poll returned an error.");
  }

  const task = body.data?.list?.[0];
  if (!task) return { status: "processing" };
  const error = task.userErrorTipMsg || task.errorMsg;
  if (error) return { status: "failed", error };
  if (task.status === 2 && Array.isArray(task.resultList) && task.resultList.length > 0) {
    const output = extractOutputFromTask(task, mediaType);
    return output.success
      ? { status: "completed", output }
      : { status: "failed", error: output.error || "PopiServer task completed without output" };
  }
  return { status: "processing" };
}