app.py

import json
import os
from typing import Dict, Any

import joblib
import pandas as pd
from fastapi import FastAPI, HTTPException
from pydantic import BaseModel

# Initialize FastAPI app
app = FastAPI(
    title="Game of Thrones House Predictor",
    description="Predict which GoT house a character belongs to based on their traits",
    version="1.0.0"
)

# Load model and metadata
MODEL_DIR = os.path.join(os.path.dirname(__file__), "model")
model = joblib.load(os.path.join(MODEL_DIR, "model.joblib"))

with open(os.path.join(MODEL_DIR, "feature_columns.json"), "r") as f:
    feature_columns = json.load(f)["columns"]

with open(os.path.join(MODEL_DIR, "label_classes.json"), "r") as f:
    label_classes = json.load(f)["classes"]


# Input schema
class CharacterInput(BaseModel):
    region: str
    primary_role: str
    alignment: str
    status: str
    species: str
    honour_1to5: int
    ruthlessness_1to5: int
    intelligence_1to5: int
    combat_skill_1to5: int
    diplomacy_1to5: int
    leadership_1to5: int
    trait_loyal: bool
    trait_scheming: bool

    class Config:
        json_schema_extra = {
            "example": {
                "region": "The North",
                "primary_role": "Commander",
                "alignment": "Lawful Good",
                "status": "Alive",
                "species": "Human",
                "honour_1to5": 4,
                "ruthlessness_1to5": 2,
                "intelligence_1to5": 3,
                "combat_skill_1to5": 4,
                "diplomacy_1to5": 3,
                "leadership_1to5": 4,
                "trait_loyal": True,
                "trait_scheming": False
            }
        }


# Output schema
class PredictionOutput(BaseModel):
    predicted_house: str
    confidence: float
    all_probabilities: Dict[str, float]


def preprocess_input(input_data: CharacterInput) -> pd.DataFrame:
    """
    Transform input JSON to match the one-hot encoded features from training.
    """
    # Convert input to dict
    data_dict = input_data.model_dump()
    
    # Add missing trait columns with default values (0)
    # The model was trained with these traits, but input doesn't have them
    data_dict["trait_strategic"] = 0
    data_dict["trait_impulsive"] = 0
    data_dict["trait_charismatic"] = 0
    data_dict["trait_vengeful"] = 0
    data_dict["feature_set_version"] = 1.0
    
    # Convert boolean traits to int
    for key in data_dict:
        if isinstance(data_dict[key], bool):
            data_dict[key] = int(data_dict[key])
    
    # Create DataFrame with single row
    df = pd.DataFrame([data_dict])
    
    # One-hot encode categorical columns
    categorical_cols = ["region", "primary_role", "alignment", "status", "species"]
    df_encoded = pd.get_dummies(df, columns=categorical_cols, dummy_na=True)
    
    # Align with training features (add missing columns, remove extra ones)
    for col in feature_columns:
        if col not in df_encoded.columns:
            df_encoded[col] = 0
    
    # Reorder columns to match training
    df_encoded = df_encoded[feature_columns]
    
    return df_encoded


@app.get("/")
def root():
    """Root endpoint with API information."""
    return {
        "message": "Game of Thrones House Predictor API",
        "endpoints": {
            "predict": "/predict",
            "docs": "/docs",
            "health": "/health"
        }
    }


@app.get("/health")
def health_check():
    """Health check endpoint."""
    return {"status": "healthy", "model_loaded": model is not None}


@app.post("/predict", response_model=PredictionOutput)
def predict(character: CharacterInput):
    """
    Predict the Game of Thrones house for a character based on their traits.
    """
    try:
        # Preprocess input
        X = preprocess_input(character)
        
        # Make prediction
        prediction = model.predict(X)[0]
        
        # Get probabilities if available (Decision Tree has predict_proba)
        if hasattr(model, "predict_proba"):
            probabilities = model.predict_proba(X)[0]
            confidence = float(max(probabilities))
            
            # Create dict of all probabilities
            all_probs = {
                label_classes[i]: float(probabilities[i])
                for i in range(len(label_classes))
            }
        else:
            confidence = 1.0
            all_probs = {prediction: 1.0}
        
        return PredictionOutput(
            predicted_house=prediction,
            confidence=confidence,
            all_probabilities=all_probs
        )
    
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Prediction error: {str(e)}")


if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8001)