import { Injectable } from '@nestjs/common';
import { AiJobStatus, AiJobType } from '@prisma/client';
import { ZodType } from 'zod';

import {
  CopilotPromptNotFound,
  CopilotTranscriptionJobExists,
  CopilotTranscriptionJobNotFound,
  EventBus,
  type FileUpload,
  JobQueue,
  NoCopilotProviderAvailable,
  OnEvent,
  OnJob,
} from '../../../base';
import { Models } from '../../../models';
import { PromptService } from '../prompt';
import {
  CopilotProvider,
  CopilotProviderFactory,
  CopilotProviderType,
  ModelOutputType,
  PromptMessage,
} from '../providers';
import { CopilotStorage } from '../storage';
import {
  AudioBlobInfos,
  TranscriptionPayload,
  TranscriptionResponseSchema,
  TranscriptPayloadSchema,
} from './types';
import { readStream } from './utils';

export type TranscriptionJob = {
  id: string;
  status: AiJobStatus;
  infos?: AudioBlobInfos;
  transcription?: TranscriptionPayload;
};

@Injectable()
export class CopilotTranscriptionService {
  constructor(
    private readonly event: EventBus,
    private readonly models: Models,
    private readonly job: JobQueue,
    private readonly storage: CopilotStorage,
    private readonly prompt: PromptService,
    private readonly providerFactory: CopilotProviderFactory
  ) {}

  private async getModel(userId: string) {
    const prompt = await this.prompt.get('Transcript audio');
    const hasAccess = await this.models.userFeature.has(
      userId,
      'unlimited_copilot'
    );
    // choose the pro model if user has copilot plan
    return prompt?.optionalModels[hasAccess ? 1 : 0];
  }

  async submitJob(
    userId: string,
    workspaceId: string,
    blobId: string,
    blobs: FileUpload[]
  ): Promise<TranscriptionJob> {
    if (await this.models.copilotJob.has(userId, workspaceId, blobId)) {
      throw new CopilotTranscriptionJobExists();
    }

    const { id: jobId } = await this.models.copilotJob.create({
      workspaceId,
      blobId,
      createdBy: userId,
      type: AiJobType.transcription,
    });

    const infos: AudioBlobInfos = [];
    for (const [idx, blob] of blobs.entries()) {
      const buffer = await readStream(blob.createReadStream());
      const url = await this.storage.put(
        userId,
        workspaceId,
        `${blobId}-${idx}`,
        buffer
      );
      infos.push({ url, mimeType: blob.mimetype });
    }

    const model = await this.getModel(userId);
    return await this.executeJob(jobId, infos, model);
  }

  async retryJob(userId: string, workspaceId: string, jobId: string) {
    const job = await this.queryJob(userId, workspaceId, jobId);
    if (!job || !job.infos) {
      throw new CopilotTranscriptionJobNotFound();
    }

    const model = await this.getModel(userId);
    const jobResult = await this.executeJob(job.id, job.infos, model);

    return jobResult;
  }

  async executeJob(
    jobId: string,
    infos: AudioBlobInfos,
    modelId?: string
  ): Promise<TranscriptionJob> {
    const status = AiJobStatus.running;
    const success = await this.models.copilotJob.update(jobId, {
      status,
      payload: { infos },
    });

    if (!success) {
      throw new CopilotTranscriptionJobNotFound();
    }

    await this.job.add('copilot.transcript.submit', {
      jobId,
      infos,
      modelId,
    });

    return { id: jobId, status };
  }

  async claimJob(
    userId: string,
    jobId: string
  ): Promise<TranscriptionJob | null> {
    const status = await this.models.copilotJob.claim(jobId, userId);
    if (status === AiJobStatus.claimed) {
      const transcription = await this.models.copilotJob.getPayload(
        jobId,
        TranscriptPayloadSchema
      );
      return { id: jobId, transcription, status };
    }
    return null;
  }

  async queryJob(
    userId: string,
    workspaceId: string,
    jobId?: string,
    blobId?: string
  ) {
    const job = await this.models.copilotJob.getWithUser(
      userId,
      workspaceId,
      jobId,
      blobId,
      AiJobType.transcription
    );

    if (!job) {
      return null;
    }

    const ret: TranscriptionJob = { id: job.id, status: job.status };

    const payload = TranscriptPayloadSchema.safeParse(job.payload);
    if (payload.success) {
      let { url, mimeType, infos } = payload.data;
      infos = infos || [];
      if (url && mimeType) {
        infos.push({ url, mimeType });
      }

      ret.infos = this.mergeInfos(infos, url, mimeType);
      if (job.status === AiJobStatus.claimed) {
        ret.transcription = payload.data;
      }
    }

    return ret;
  }

  private async getProvider(
    modelId: string,
    structured: boolean,
    prefer?: CopilotProviderType
  ): Promise<CopilotProvider> {
    let provider = await this.providerFactory.getProvider(
      {
        outputType: structured
          ? ModelOutputType.Structured
          : ModelOutputType.Text,
        modelId,
      },
      { prefer }
    );

    if (!provider) {
      throw new NoCopilotProviderAvailable({ modelId });
    }

    return provider;
  }

  private async chatWithPrompt(
    promptName: string,
    message: Partial<PromptMessage>,
    schema?: ZodType<any>,
    prefer?: CopilotProviderType,
    modelId?: string
  ): Promise<string> {
    const prompt = await this.prompt.get(promptName);
    if (!prompt) {
      throw new CopilotPromptNotFound({ name: promptName });
    }

    const cond = {
      modelId:
        modelId && prompt.optionalModels.includes(modelId)
          ? modelId
          : prompt.model,
    };
    const msg = { role: 'user' as const, content: '', ...message };
    const config = Object.assign({}, prompt.config);
    if (schema) {
      const provider = await this.getProvider(prompt.model, true, prefer);
      return provider.structure(
        cond,
        [...prompt.finish({ schema }), msg],
        config
      );
    } else {
      const provider = await this.getProvider(prompt.model, false);
      return provider.text(cond, [...prompt.finish({}), msg], config);
    }
  }

  // TODO(@darkskygit): remove after old server down
  private mergeInfos(
    infos?: AudioBlobInfos | null,
    url?: string | null,
    mimeType?: string | null
  ) {
    if (url && mimeType) {
      if (infos) {
        infos.push({ url, mimeType });
      } else {
        infos = [{ url, mimeType }];
      }
    }
    return infos || [];
  }

  private convertTime(time: number, offset = 0) {
    time = time + offset;
    const minutes = Math.floor(time / 60);
    const seconds = Math.floor(time % 60);
    const hours = Math.floor(minutes / 60);
    const minutesStr = String(minutes % 60).padStart(2, '0');
    const secondsStr = String(seconds).padStart(2, '0');
    const hoursStr = String(hours).padStart(2, '0');
    return `${hoursStr}:${minutesStr}:${secondsStr}`;
  }

  private async callTranscript(
    url: string,
    mimeType: string,
    offset: number,
    modelId?: string
  ) {
    // NOTE: Vertex provider not support transcription yet, we always use Gemini here
    const result = await this.chatWithPrompt(
      'Transcript audio',
      { attachments: [url], params: { mimetype: mimeType } },
      TranscriptionResponseSchema,
      CopilotProviderType.Gemini,
      modelId
    );

    const transcription = TranscriptionResponseSchema.parse(
      JSON.parse(result)
    ).map(t => ({
      speaker: t.a,
      start: this.convertTime(t.s, offset),
      end: this.convertTime(t.e, offset),
      transcription: t.t,
    }));

    return transcription;
  }

  @OnJob('copilot.transcript.submit')
  async transcriptAudio({
    jobId,
    infos,
    modelId,
    // @deprecated
    url,
    mimeType,
  }: Jobs['copilot.transcript.submit']) {
    try {
      const blobInfos = this.mergeInfos(infos, url, mimeType);
      const transcriptions = await Promise.all(
        Array.from(blobInfos.entries()).map(([idx, { url, mimeType }]) =>
          this.callTranscript(url, mimeType, idx * 10 * 60, modelId)
        )
      );

      await this.models.copilotJob.update(jobId, {
        payload: { transcription: transcriptions.flat() },
      });

      await this.job.add('copilot.transcript.summary.submit', {
        jobId,
      });
      return;
    } catch (error: any) {
      // record failed status and passthrough error
      this.event.emit('workspace.file.transcript.failed', {
        jobId,
      });
      throw error;
    }
  }

  @OnJob('copilot.transcript.summary.submit')
  async transcriptSummary({
    jobId,
  }: Jobs['copilot.transcript.summary.submit']) {
    try {
      const payload = await this.models.copilotJob.getPayload(
        jobId,
        TranscriptPayloadSchema
      );
      if (payload.transcription) {
        const content = payload.transcription
          .map(t => t.transcription.trim())
          .join('\n')
          .trim();

        if (content.length) {
          payload.summary = await this.chatWithPrompt('Summarize the meeting', {
            content,
          });
          await this.models.copilotJob.update(jobId, {
            payload,
          });

          await this.job.add('copilot.transcript.title.submit', {
            jobId,
          });
          return;
        }
      }
      this.event.emit('workspace.file.transcript.failed', {
        jobId,
      });
    } catch (error: any) {
      // record failed status and passthrough error
      this.event.emit('workspace.file.transcript.failed', {
        jobId,
      });
      throw error;
    }
  }

  @OnJob('copilot.transcript.title.submit')
  async transcriptTitle({ jobId }: Jobs['copilot.transcript.title.submit']) {
    try {
      const payload = await this.models.copilotJob.getPayload(
        jobId,
        TranscriptPayloadSchema
      );
      if (payload.transcription && payload.summary) {
        const content = payload.transcription
          .map(t => t.transcription.trim())
          .join('\n')
          .trim();

        if (content.length) {
          payload.title = await this.chatWithPrompt('Summary as title', {
            content,
          });
          await this.models.copilotJob.update(jobId, {
            payload,
          });
          await this.job.add('copilot.transcript.findAction.submit', {
            jobId,
          });
          return;
        }
      }
      this.event.emit('workspace.file.transcript.failed', {
        jobId,
      });
    } catch (error: any) {
      // record failed status and passthrough error
      this.event.emit('workspace.file.transcript.failed', {
        jobId,
      });
      throw error;
    }
  }

  @OnJob('copilot.transcript.findAction.submit')
  async transcriptFindAction({
    jobId,
  }: Jobs['copilot.transcript.findAction.submit']) {
    try {
      const payload = await this.models.copilotJob.getPayload(
        jobId,
        TranscriptPayloadSchema
      );
      if (payload.summary) {
        const actions = await this.chatWithPrompt('Find action for summary', {
          content: payload.summary,
        }).then(a => a.trim());
        if (actions) {
          payload.actions = actions;
          await this.models.copilotJob.update(jobId, {
            payload,
          });
        }
      }
    } catch {} // finish even if failed
    this.event.emit('workspace.file.transcript.finished', {
      jobId,
    });
  }

  @OnEvent('workspace.file.transcript.finished')
  async onFileTranscriptFinish({
    jobId,
  }: Events['workspace.file.transcript.finished']) {
    await this.models.copilotJob.update(jobId, {
      status: AiJobStatus.finished,
    });
  }

  @OnEvent('workspace.file.transcript.failed')
  async onFileTranscriptFailed({
    jobId,
  }: Events['workspace.file.transcript.failed']) {
    await this.models.copilotJob.update(jobId, {
      status: AiJobStatus.failed,
    });
  }
}