package com.smartor.common.enums;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

/**
 * 住院状态枚举
 * 
 * @author smartor
 */
public enum InhospStateEnum {
    
    /**
     * 预入院状态
     */
    PRE_ADMISSION("3", "预入院", new String[]{"0"}),
    
    /**
     * 在院状态
     */
    IN_HOSPITAL("0", "在院", new String[]{"1"}),
    
    /**
     * 出院状态
     */
    DISCHARGED("1", "出院", new String[]{});

    /**
     * 状态码
     */
    private final String code;
    
    /**
     * 状态描述
     */
    private final String description;
    
    /**
     * 允许转换的下一状态码集合
     */
    private final Set<String> allowedNextStates;

    InhospStateEnum(String code, String description, String[] allowedNextStates) {
        this.code = code;
        this.description = description;
        this.allowedNextStates = new HashSet<>(Arrays.asList(allowedNextStates));
    }

    public String getCode() {
        return code;
    }

    public String getDescription() {
        return description;
    }

    /**
     * 判断是否允许转换到目标状态
     * 
     * @param targetStateCode 目标状态码
     * @return 是否允许转换
     */
    public boolean canTransitionTo(String targetStateCode) {
        return allowedNextStates.contains(targetStateCode);
    }

    /**
     * 根据状态码获取枚举
     * 
     * @param code 状态码
     * @return 对应的枚举,如果不存在返回null
     */
    public static InhospStateEnum fromCode(String code) {
        for (InhospStateEnum state : values()) {
            if (state.getCode().equals(code)) {
                return state;
            }
        }
        return null;
    }

    /**
     * 验证状态转换是否合法
     * 
     * @param currentStateCode 当前状态码
     * @param targetStateCode 目标状态码
     * @return 是否允许转换
     */
    public static boolean isValidTransition(String currentStateCode, String targetStateCode) {
        if (currentStateCode == null) {
            // 初始状态，只允许创建预入院或在院
            return "3".equals(targetStateCode) || "0".equals(targetStateCode);
        }
        
        InhospStateEnum currentState = fromCode(currentStateCode);
        if (currentState == null) {
            return false;
        }
        
        return currentState.canTransitionTo(targetStateCode);
    }

    /**
     * 获取所有允许的下一状态
     * 
     * @return 允许的下一状态集合
     */
    public Set<String> getAllowedNextStates() {
        return new HashSet<>(allowedNextStates);
    }
}