feat: Add endpoint to retrieve random audio based on limit and recite…

…r ID #31

src/audio/audio.controller.ts

@@ -3,6 +3,7 @@ import { AudioService } from './audio.service';
 import { CreateAudioDto } from './dto/create-audio.dto';
 import { FilterAudioDto } from './dto/filter-audio.dto';
 import { FilterAudioLrcDto } from './dto/filter-lrc.dto';
+import { RandomDto } from './dto/random.dto';
 
 @Controller('audio')
 export class AudioController {
@@ -22,4 +23,12 @@ export class AudioController {
   getLrc(@Query() filterAudioLrcDto: FilterAudioLrcDto) {
     return this.audioService.getAudioLrc(filterAudioLrcDto);
   }
+
+  @Get('/random')
+  getRandom(@Query() randomDto: RandomDto) {
+    return this.audioService.getRandomAudio(
+      randomDto.limit,
+      randomDto.reciter_id,
+    );
+  }
 }

src/audio/audio.service.ts

@@ -59,4 +59,45 @@ export class AudioService {
       },
     });
   }
+
+  async getRandomAudio(limit: number, reciter_id: number) {
+    if (limit < 1) {
+      throw new Error('Limit must be greater than 0');
+    }
+
+    const tilawat = await this.reciterService.getReciterTilawa(reciter_id);
+
+    if (!tilawat?.length) {
+      throw new Error('No tilawat found for this reciter');
+    }
+
+    // Use more efficient random selection for tilawa
+    const randomTilawaIndex = Math.floor(Math.random() * tilawat.length);
+    const randomTilawa = tilawat[randomTilawaIndex];
+
+    const audioRecords = await this.tilawaSurahRepo.find({
+      select: ['tilawa_id', 'url'],
+      where: {
+        tilawa_id: randomTilawa.id,
+      },
+      relations: {
+        surah: true,
+        tilawa: {
+          reciter: true,
+        },
+      },
+    });
+
+    if (!audioRecords?.length) {
+      return [];
+    }
+
+    // Use Fisher-Yates shuffle algorithm for randomization
+    for (let i = audioRecords.length - 1; i > 0; i--) {
+      const j = Math.floor(Math.random() * (i + 1));
+      [audioRecords[i], audioRecords[j]] = [audioRecords[j], audioRecords[i]];
+    }
+
+    return audioRecords.slice(0, Math.min(limit, audioRecords.length));
+  }
 }

src/audio/dto/random.dto.ts

@@ -0,0 +1,14 @@
+import { Transform } from 'class-transformer';
+import { IsNumber, IsPositive } from 'class-validator';
+
+export class RandomDto {
+  @IsNumber()
+  @IsPositive()
+  @Transform(({ value }) => parseInt(value))
+  limit: number;
+
+  @IsNumber()
+  @IsPositive()
+  @Transform(({ value }) => parseInt(value))
+  reciter_id: number;
+}