import numpy as np
import pandas as pd
from sklearn.metrics import accuracy_score, confusion_matrix, classification_report, precision_score, recall_score, f1_score
import sklearn.svm as svm
from sklearn.cross_decomposition import PLSRegression
from sklearn.ensemble import RandomForestClassifier
from sklearn.model_selection import GridSearchCV, cross_val_score, train_test_split
from skopt import BayesSearchCV
from skopt.space import Real, Integer
from xgboost import XGBClassifier
import lightgbm as lgb
import catboost as cb
from sklearn.linear_model import LogisticRegression
from sklearn.model_selection import StratifiedKFold
from sklearn.neural_network import MLPClassifier
# 固定随机种子
def set_random_seed(seed=42):
    np.random.seed(seed)

set_random_seed()

# 交叉验证（多核心支持）
def cross_validate_model(model, X, y, cv=5, n_jobs=-1):
    """
    多核心交叉验证
    """
    scores = cross_val_score(model, X, y, cv=cv, n_jobs=n_jobs)
    print(f"Cross-validation accuracy: {scores.mean():.4f} ± {scores.std():.4f}")
    return scores

# 混淆矩阵与分类报告
def evaluate_model(y_true, y_pred, dataset_name="Test"):
    """
    性能评估，包含分类报告和混淆矩阵。
    """
    print(f"{dataset_name} Classification Report:")
    print(classification_report(y_true, y_pred))

    # 计算混淆矩阵
    cm = confusion_matrix(y_true, y_pred)

    # 返回多个性能指标的字典，包括F1分数
    return {
        "accuracy": accuracy_score(y_true, y_pred),
        "precision": precision_score(y_true, y_pred, average='weighted'),
        "recall": recall_score(y_true, y_pred, average='weighted'),
        "f1_score": f1_score(y_true, y_pred, average='weighted'),
        "confusion_matrix": cm
    }

# 逻辑回归模型 (Logistic Regression)
from sklearn.svm import SVC
from sklearn.neighbors import KNeighborsClassifier
from sklearn.ensemble import RandomForestClassifier
import xgboost as xgb
import lightgbm as lgb
import catboost as cb
from sklearn.linear_model import LogisticRegression
from sklearn.model_selection import train_test_split

# 1. SVM 贝叶斯优化
def optimize_SVM(X_train, y_train, X_test, y_test):
    param_space = {
        'C': (0.01, 10.0, 'uniform'),
        'kernel': ['linear', 'poly', 'rbf', 'sigmoid'],
        'gamma': (1e-4, 1e-1, 'log-uniform')
    }

    model = SVC()
    optimizer = BayesSearchCV(model, param_space, n_iter=50, cv=5, n_jobs=-1, verbose=0, scoring='f1_weighted')  # 使用f1_weighted作为评分标准
    optimizer.fit(X_train, y_train)

    best_params = optimizer.best_params_

    # 使用最优超参数训练并评估模型
    best_model = optimizer.best_estimator_
    y_train_pred = best_model.predict(X_train)
    y_test_pred = best_model.predict(X_test)

    train_metrics = evaluate_model(y_train, y_train_pred, dataset_name="Train")
    test_metrics = evaluate_model(y_test, y_test_pred, dataset_name="Test")

    return best_params, train_metrics, test_metrics

# 2. KNN 贝叶斯优化
def optimize_KNN(X_train, y_train, X_test, y_test):
    param_space = {
        'n_neighbors': (1, 20),
        'weights': ['uniform', 'distance'],
        'algorithm': ['auto', 'ball_tree', 'kd_tree', 'brute']
    }

    model = KNeighborsClassifier()
    optimizer = BayesSearchCV(model, param_space, n_iter=50, cv=5, n_jobs=-1, verbose=0, scoring='f1_weighted')  # 使用f1_weighted作为评分标准
    optimizer.fit(X_train, y_train)

    best_params = optimizer.best_params_

    # 使用最优超参数训练并评估模型
    best_model = optimizer.best_estimator_
    y_train_pred = best_model.predict(X_train)
    y_test_pred = best_model.predict(X_test)

    train_metrics = evaluate_model(y_train, y_train_pred, dataset_name="Train")
    test_metrics = evaluate_model(y_test, y_test_pred, dataset_name="Test")

    return best_params, train_metrics, test_metrics

# 3. XGBoost 贝叶斯优化
def optimize_XGBoost(X_train, y_train, X_test, y_test):
    param_space = {
        'n_estimators': Integer(50, 500),
        'max_depth': Integer(3, 10),
        'learning_rate': Real(1e-4, 1.0, prior='log-uniform'),
        'subsample': Real(0.1, 1.0),
        'colsample_bytree': Real(0.1, 1.0)
    }

    model = XGBClassifier(tree_method='gpu_hist', gpu_id=0)
    optimizer = BayesSearchCV(model, param_space, n_iter=50, cv=5, n_jobs=-1, verbose=0, scoring='f1_weighted')  # 使用f1_weighted作为评分标准

    optimizer.fit(X_train, y_train)

    best_params = optimizer.best_params_
    best_model = optimizer.best_estimator_

    y_train_pred = best_model.predict(X_train)
    y_test_pred = best_model.predict(X_test)

    train_metrics = evaluate_model(y_train, y_train_pred, dataset_name="Train")
    test_metrics = evaluate_model(y_test, y_test_pred, dataset_name="Test")

    return best_params, train_metrics, test_metrics

# 4. Random Forest 贝叶斯优化
def optimize_RF(X_train, y_train, X_test, y_test):
    param_space = {
        'n_estimators': (50, 500),
        'max_depth': (3, 15),
        'min_samples_split': (2, 20),
        'min_samples_leaf': (1, 20),
        'max_features': ['auto', 'sqrt', 'log2']
    }

    model = RandomForestClassifier(random_state=42)
    optimizer = BayesSearchCV(model, param_space, n_iter=50, cv=5, n_jobs=-1, verbose=0, scoring='f1_weighted')  # 使用f1_weighted作为评分标准
    optimizer.fit(X_train, y_train)

    best_params = optimizer.best_params_

    # 使用最优超参数训练并评估模型
    best_model = optimizer.best_estimator_
    y_train_pred = best_model.predict(X_train)
    y_test_pred = best_model.predict(X_test)

    train_metrics = evaluate_model(y_train, y_train_pred, dataset_name="Train")
    test_metrics = evaluate_model(y_test, y_test_pred, dataset_name="Test")

    return best_params, train_metrics, test_metrics

# 5. CatBoost 贝叶斯优化
def optimize_CatBoost(X_train, y_train, X_test, y_test):
    param_space = {
        'iterations': (50, 500),
        'learning_rate': (0.01, 0.3, 'uniform'),
        'depth': (3, 10),
        'l2_leaf_reg': (1, 10, 'uniform'),
        'bagging_temperature': (0, 1, 'uniform')
    }

    model = cb.CatBoostClassifier(task_type='GPU', random_seed=42, verbose=0)
    optimizer = BayesSearchCV(model, param_space, n_iter=50, cv=5, n_jobs=-1, verbose=0, scoring='f1_weighted')  # 使用f1_weighted作为评分标准
    optimizer.fit(X_train, y_train)

    best_params = optimizer.best_params_

    # 使用最优超参数训练并评估模型
    best_model = optimizer.best_estimator_
    y_train_pred = best_model.predict(X_train)
    y_test_pred = best_model.predict(X_test)

    train_metrics = evaluate_model(y_train, y_train_pred, dataset_name="Train")
    test_metrics = evaluate_model(y_test, y_test_pred, dataset_name="Test")

    return best_params, train_metrics, test_metrics

# 6. Logistic Regression 贝叶斯优化
def optimize_LogisticRegression(X_train, y_train, X_test, y_test):
    param_space = {
        'C': (1e-5, 1e5, 'log-uniform'),
        'penalty': ['l1', 'l2'],
        'solver': ['lbfgs', 'liblinear', 'saga']
    }

    model = LogisticRegression(multi_class='multinomial', random_state=42)
    optimizer = BayesSearchCV(model, param_space, n_iter=50, cv=5, n_jobs=-1, verbose=0, scoring='f1_weighted')  # 使用f1_weighted作为评分标准
    optimizer.fit(X_train, y_train)

    best_params = optimizer.best_params_

    # 使用最优超参数训练并评估模型
    best_model = optimizer.best_estimator_
    y_train_pred = best_model.predict(X_train)
    y_test_pred = best_model.predict(X_test)

    train_metrics = evaluate_model(y_train, y_train_pred, dataset_name="Train")
    test_metrics = evaluate_model(y_test, y_test_pred, dataset_name="Test")

    return best_params, train_metrics, test_metrics

# 7. Neural Network (ANN) 贝叶斯优化
def optimize_ANN(X_train, y_train, X_test, y_test):
    param_space = {
        'hidden_layer_sizes': [(10,), (50,), (100,), (10, 10), (50, 50)],
        'activation': ['relu', 'tanh', 'logistic'],
        'solver': ['adam', 'sgd'],
        'alpha': (1e-5, 1e-1, 'log-uniform'),
        'learning_rate': ['constant', 'invscaling', 'adaptive']
    }

    model = MLPClassifier(max_iter=500, random_state=42)
    optimizer = BayesSearchCV(model, param_space, n_iter=50, cv=5, n_jobs=-1, verbose=0, scoring='f1_weighted')  # 使用f1_weighted作为评分标准
    optimizer.fit(X_train, y_train)

    best_params = optimizer.best_params_

    # 使用最优超参数训练并评估模型
    best_model = optimizer.best_estimator_
    y_train_pred = best_model.predict(X_train)
    y_test_pred = best_model.predict(X_test)

    train_metrics = evaluate_model(y_train, y_train_pred, dataset_name="Train")
    test_metrics = evaluate_model(y_test, y_test_pred, dataset_name="Test")

    return best_params, train_metrics, test_metrics