import { Buffer } from 'node:buffer';
import { mkdir, readFile, stat, writeFile } from 'node:fs/promises';
import path from 'node:path';
import type { CodingPluginToolDefinition } from '../../../shared/coding-plugins';
import { PiGameAssetTools } from '../../coding-runtime/pi/extensions/game-assets';
import type { MarketplacePackageClientPort, PluginPackageStore } from '../package-store';
import {
  MarketplaceHostedAdmissionError,
  MarketplaceHostedAdmissionResolver,
} from '../hosted-admission';
import {
  GameResourceClient,
  GameResourceClientError,
  type GameResourceGeneration,
} from '../../services/game-resource-client';
import type {
  AdapterInvocationResult,
  CodingPluginAdapter,
  PluginBackendProjection,
  TrustedCodingCapabilityContext,
} from '../registry';

const PLUGIN_ID = 'makelore.game-resource';
const MAX_REFERENCE_FILE_BYTES = 8 * 1024 * 1024;
const MAX_REFERENCE_BYTES = 16 * 1024 * 1024;
const EXECUTION_ID = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/u;

type Input = Record<string, unknown>;

export interface GameResourcePluginAdapterOptions {
  readonly client: GameResourceClient;
  readonly marketplace: MarketplacePackageClientPort;
  readonly packageStore: Pick<PluginPackageStore, 'getInstalled' | 'getInstalledRelease'>;
  readonly makeloreVersion: string;
  readonly admissionResolver?: MarketplaceHostedAdmissionResolver;
  readonly gameAssets?: PiGameAssetTools;
}

function isRecord(value: unknown): value is Input {
  return value !== null && typeof value === 'object' && !Array.isArray(value);
}

function success<T>(
  data: T,
  status = 200,
  billing?: Extract<NonNullable<AdapterInvocationResult['billing']>, { mode: 'platform_metered' }>,
): AdapterInvocationResult<T> {
  return {
    success: true,
    status,
    code: null,
    error: null,
    retryable: false,
    payload_schema: 'game-resource.v1',
    data,
    ...(billing ? { billing } : {}),
  };
}

function failure(
  code: string,
  error: string,
  status: number,
  retryable: boolean,
  billing?: Extract<NonNullable<AdapterInvocationResult['billing']>, { mode: 'platform_metered' }>,
): AdapterInvocationResult {
  return {
    success: false,
    status,
    code,
    error,
    retryable,
    payload_schema: 'game-resource.v1',
    data: null,
    ...(billing ? { billing } : {}),
  };
}

function generationData(value: GameResourceGeneration, includeBilling: boolean) {
  return {
    executionId: value.executionId,
    status: value.status,
    outputCount: value.outputCount,
    ...(value.pollIntervalSeconds === undefined ? {} : { pollIntervalSeconds: value.pollIntervalSeconds }),
    ...(value.errorCode === undefined ? {} : { errorCode: value.errorCode }),
    ...(includeBilling ? { generationBilling: value.billing } : {}),
  };
}

function clientFailure(error: unknown): AdapterInvocationResult {
  if (error instanceof GameResourceClientError) {
    return failure(error.code, error.message, error.status, error.retryable);
  }
  if (error instanceof MarketplaceHostedAdmissionError) {
    return failure(error.code, error.message, error.status, error.retryable);
  }
  return failure(
    'plugin_backend_unavailable',
    'Hosted game-resource service is temporarily unavailable',
    503,
    true,
  );
}

function relativeProjectPath(projectPath: string, candidate: unknown): { absolute: string; relative: string } {
  if (typeof candidate !== 'string' || !candidate.trim() || candidate.length > 1_024) {
    throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Project-relative path is invalid');
  }
  const root = path.resolve(projectPath);
  const absolute = path.resolve(root, candidate);
  const relative = path.relative(root, absolute);
  if (!relative || relative.startsWith('..') || path.isAbsolute(relative)) {
    throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Project-relative path is invalid');
  }
  return { absolute, relative: relative.split(path.sep).join('/') };
}

function mimeType(filePath: string): string {
  switch (path.extname(filePath).toLowerCase()) {
    case '.jpg':
    case '.jpeg': return 'image/jpeg';
    case '.webp': return 'image/webp';
    case '.gif': return 'image/gif';
    default: return 'image/png';
  }
}

async function references(projectPath: string, value: unknown) {
  if (value === undefined) return [];
  if (!Array.isArray(value) || value.length > 8) {
    throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Reference paths are invalid');
  }
  let total = 0;
  return await Promise.all(value.map(async (candidate) => {
    const target = relativeProjectPath(projectPath, candidate);
    const metadata = await stat(target.absolute).catch(() => null);
    if (!metadata?.isFile() || metadata.size <= 0 || metadata.size > MAX_REFERENCE_FILE_BYTES) {
      throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Reference file is unavailable or too large');
    }
    total += metadata.size;
    if (total > MAX_REFERENCE_BYTES) {
      throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Reference files exceed their total bound');
    }
    return {
      name: path.basename(target.absolute).slice(0, 160),
      mimeType: mimeType(target.absolute),
      dataBase64: (await readFile(target.absolute)).toString('base64'),
    };
  }));
}

function templateConfig(value: unknown): Readonly<Record<string, unknown>> {
  if (value === undefined || value === '') return {};
  if (typeof value !== 'string' || Buffer.byteLength(value, 'utf8') > 16_384) {
    throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Template config JSON is invalid');
  }
  let parsed: unknown;
  try { parsed = JSON.parse(value) as unknown; } catch {
    throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Template config JSON is invalid');
  }
  if (!isRecord(parsed)) {
    throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Template config JSON must be an object');
  }
  return parsed;
}

export class GameResourcePluginAdapter implements CodingPluginAdapter {
  readonly pluginId = PLUGIN_ID;
  private readonly gameAssets: PiGameAssetTools;
  private readonly admissionResolver: MarketplaceHostedAdmissionResolver;

  constructor(private readonly options: GameResourcePluginAdapterOptions) {
    this.gameAssets = options.gameAssets ?? new PiGameAssetTools();
    this.admissionResolver = options.admissionResolver ?? new MarketplaceHostedAdmissionResolver({
      marketplace: options.marketplace,
      packageStore: options.packageStore,
      makeloreVersion: options.makeloreVersion,
    });
  }

  async inspect(): Promise<PluginBackendProjection> {
    const installed = await this.options.packageStore.getInstalled(PLUGIN_ID).catch(() => null);
    return installed ? { status: 'ready' } : { status: 'unconfigured' };
  }

  async invoke(
    context: TrustedCodingCapabilityContext,
    tool: CodingPluginToolDefinition,
    input: unknown,
  ): Promise<AdapterInvocationResult> {
    if (!isRecord(input)) return failure('plugin_input_invalid', 'Game-resource tool input is invalid', 422, false);
    try {
      switch (tool.name) {
        case 'game_resource_templates': {
          const kind = input.kind === 'pixel' || input.kind === 'hd' ? input.kind : null;
          if (!kind) return failure('plugin_input_invalid', 'Game-resource kind is invalid', 422, false);
          const admission = await this.admission(context);
          return success({ kind, templates: await this.options.client.templates({ ...admission, kind }) });
        }
        case 'game_resource_generate': {
          if (input.confirmed !== true) {
            return failure(
              'confirmation_required',
              'Explicit Token Point generation confirmation is required',
              400,
              false,
            );
          }
          const kind = input.kind === 'pixel' || input.kind === 'hd' ? input.kind : null;
          if (!kind || typeof input.templateName !== 'string' || typeof input.requirement !== 'string') {
            return failure('plugin_input_invalid', 'Game-resource generation input is invalid', 422, false);
          }
          const admission = await this.admission(context);
          const generated = await this.options.client.generate({
            ...admission,
            projectId: context.durableProjectId,
            logicalOperationId: context.requestId,
            kind,
            templateName: input.templateName,
            templateConfig: templateConfig(input.templateConfigJson),
            requirement: input.requirement,
            ...(typeof input.aspectRatio === 'string' ? { aspectRatio: input.aspectRatio } : {}),
            ...(typeof input.temperature === 'number' ? { temperature: input.temperature } : {}),
            ...(typeof input.jobName === 'string' ? { jobName: input.jobName } : {}),
            ...(typeof input.modelName === 'string' ? { modelName: input.modelName } : {}),
            ...(typeof input.resolution === 'string' ? { resolution: input.resolution } : {}),
            ...(typeof input.hdRemoveBgMode === 'string' ? { hdRemoveBgMode: input.hdRemoveBgMode } : {}),
            ...(typeof input.threadId === 'string' ? { threadId: input.threadId } : {}),
            referenceFiles: await references(context.projectPath, input.referencePaths),
          });
          if (generated.status === 'failed' || generated.status === 'cancelled') {
            return failure(
              generated.errorCode ?? 'game_resource_generation_failed',
              'Hosted game-resource generation was rejected',
              422,
              false,
              generated.billing,
            );
          }
          return success(
            generationData(generated, false),
            generated.status === 'succeeded' ? 200 : 202,
            generated.billing,
          );
        }
        case 'game_resource_status': {
          const executionId = this.executionId(input.executionId);
          const generated = await this.options.client.get(executionId);
          return success(generationData(generated, true));
        }
        case 'game_resource_cancel': {
          const executionId = this.executionId(input.executionId);
          const generated = await this.options.client.cancel(executionId);
          return success(generationData(generated, true));
        }
        case 'game_resource_save_output': {
          if (input.confirmed !== true) return failure('confirmation_required', 'Explicit save confirmation is required', 400, false);
          const executionId = this.executionId(input.executionId);
          const outputIndex = input.outputIndex === undefined ? undefined : input.outputIndex;
          if (outputIndex !== undefined && (!Number.isSafeInteger(outputIndex) || (outputIndex as number) < 0 || (outputIndex as number) > 99)) {
            return failure('plugin_input_invalid', 'Game-resource output index is invalid', 422, false);
          }
          const target = relativeProjectPath(context.projectPath, input.relativePath);
          const content = await this.options.client.download(executionId, outputIndex as number | undefined);
          await mkdir(path.dirname(target.absolute), { recursive: true });
          try {
            await writeFile(target.absolute, content.bytes, { flag: 'wx' });
          } catch (error) {
            if (isRecord(error) && error.code === 'EEXIST') {
              return failure('game_resource_destination_exists', 'Destination file already exists', 409, false);
            }
            throw error;
          }
          return success({ savedPath: target.relative, bytes: content.bytes.byteLength });
        }
        case 'game_asset_browser': {
          const result = await this.gameAssets.browse(context.projectPath, input, context.requestId);
          const parsed = JSON.parse(result.content[0]?.text ?? '{}') as unknown;
          return success(parsed);
        }
        case 'game_asset_review': {
          const result = await this.gameAssets.review(context.projectPath, input, context.requestId);
          return success(result.details);
        }
        default:
          return failure('plugin_contract_unsupported', 'Game-resource operation is unavailable', 503, true);
      }
    } catch (error) {
      return clientFailure(error);
    }
  }

  private executionId(value: unknown): string {
    if (typeof value !== 'string' || !EXECUTION_ID.test(value)) {
      throw new GameResourceClientError('plugin_input_invalid', 422, false, 'Execution ID is invalid');
    }
    return value;
  }

  private async admission(context: TrustedCodingCapabilityContext): Promise<{
    releaseId: string;
    releaseAdmissionId: string;
  }> {
    return this.admissionResolver.resolve({
      pluginId: PLUGIN_ID,
      workerSnapshot: {
        requestId: context.requestId,
        ...(context.pluginReleaseId === undefined ? {} : { pluginReleaseId: context.pluginReleaseId }),
      },
    });
  }
}

export function createGameResourcePluginAdapter(
  options: GameResourcePluginAdapterOptions,
): GameResourcePluginAdapter {
  return new GameResourcePluginAdapter(options);
}