const mongoose = require('mongoose');

const feedbackSchema = new mongoose.Schema({
  userId: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'User',
    required: true
  },
  comment: {
    type: String,
    required: true,
    trim: true
  },
  rating: {
    type: Number,
    min: 1,
    max: 5
  },
  createdAt: {
    type: Date,
    default: Date.now
  }
});

const voteSchema = new mongoose.Schema({
  userId: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'User',
    required: true
  },
  rank: {
    type: Number,
    enum: [1, 2, 3], // 1 = 1st place, 2 = 2nd place, 3 = 3rd place
    required: true
  },
  createdAt: {
    type: Date,
    default: Date.now
  }
});

const submissionSchema = new mongoose.Schema({
  sourceTextId: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'SourceText',
    required: true
  },
  userId: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'User',
    required: true
  },
  username: {
    type: String,
    required: true
  },
  groupNumber: {
    type: Number,
    min: 1,
    max: 8,
    required: function() {
      // Group number is required for tutorial tasks, optional for other submissions
      return this.sourceTextId && this.sourceTextId.category === 'tutorial';
    }
  },
  targetCulture: {
    type: String,
    required: true
  },
  targetLanguage: {
    type: String,
    required: true
  },
  transcreation: {
    type: String,
    required: true
  },
  explanation: {
    type: String,
    required: true
  },
  culturalAdaptations: [{
    type: String
  }],
  isAnonymous: {
    type: Boolean,
    default: true
  },
  status: {
    type: String,
    enum: ['draft', 'submitted', 'reviewed', 'approved', 'rejected'],
    default: 'submitted'
  },
  difficulty: {
    type: String,
    enum: ['beginner', 'intermediate', 'advanced'],
    default: 'intermediate'
  },
  votes: [voteSchema],
  feedback: [{
    userId: {
      type: mongoose.Schema.Types.ObjectId,
      ref: 'User'
    },
    comment: String,
    createdAt: {
      type: Date,
      default: Date.now
    }
  }],
  createdAt: {
    type: Date,
    default: Date.now
  },
  updatedAt: {
    type: Date,
    default: Date.now
  }
});

// Calculate score based on votes (1st place = 3 points, 2nd place = 2 points, 3rd place = 1 point)
submissionSchema.methods.calculateScore = function() {
  return this.votes.reduce((total, vote) => {
    const points = 4 - vote.rank; // 1st = 3 points, 2nd = 2 points, 3rd = 1 point
    return total + points;
  }, 0);
};

// Get vote count by rank
submissionSchema.methods.getVoteCountByRank = function() {
  const counts = { 1: 0, 2: 0, 3: 0 };
  this.votes.forEach(vote => {
    counts[vote.rank]++;
  });
  return counts;
};

// Update score before saving
submissionSchema.pre('save', function(next) {
  this.score = this.calculateScore();
  this.updatedAt = Date.now();
  next();
});

// Index for efficient querying
submissionSchema.index({ 
  sourceTextId: 1, 
  targetCulture: 1, 
  status: 1,
  createdAt: -1 
});

module.exports = mongoose.model('Submission', submissionSchema);