package org.bukkit.util.config;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**
 * Represents a configuration node.
 * 
 * @author sk89q
 */
public abstract class ConfigurationNode {
    protected Map<String, Object> root;
    
    ConfigurationNode(Map<String, Object> root) {
        this.root = root;
    }
    
    /**
     * Gets a property at a location. This will either return an Object
     * or null, with null meaning that no configuration value exists at
     * that location. This could potentially return a default value (not yet
     * implemented) as defined by a plugin, if this is a plugin-tied
     * configuration.
     * 
     * @param path path to node (dot notation)
     * @return object or null
     */
    @SuppressWarnings("unchecked")
    public Object getProperty(String path) {
        if (!path.contains(".")) {
            Object val = root.get(path);
            if (val == null) {
                return null;
            }
            return val;
        }
        
        String[] parts = path.split("\\.");
        Map<String, Object> node = root;
        
        for (int i = 0; i < parts.length; i++) {
            Object o = node.get(parts[i]);
            
            if (o == null) {
                return null;
            }
            
            if (i == parts.length - 1) {
                return o;
            }
            
            try {
                node = (Map<String, Object>)o;
            } catch (ClassCastException e) {
                return null;
            }
        }
        
        return null;
    }

    /**
     * Gets a string at a location. This will either return an String
     * or null, with null meaning that no configuration value exists at
     * that location. If the object at the particular location is not actually
     * a string, it will be converted to its string representation.
     * 
     * @param path path to node (dot notation)
     * @return string or null
     */
    public String getString(String path) {
        Object o = getProperty(path);
        if (o == null) {
            return null;
        }
        return o.toString();
    }

    /**
     * Gets a string at a location. This will either return an String
     * or the default value. If the object at the particular location is not
     * actually a string, it will be converted to its string representation.
     * 
     * @param path path to node (dot notation)
     * @param def default value
     * @return string or default
     */
    public String getString(String path, String def) {
        String o = getString(path);
        if (o == null) {
            return def;
        }
        return o;
    }

    /**
     * Gets an integer at a location. This will either return an integer
     * or the default value. If the object at the particular location is not
     * actually a integer, the default value will be returned. However, other
     * number types will be casted to an integer.
     * 
     * @param path path to node (dot notation)
     * @param def default value
     * @return int or default
     */
    public int getInt(String path, int def) {
        Integer o = castInt(getProperty(path));
        if (o == null) {
            return def;
        } else {
            return o;
        }
    }

    /**
     * Gets a double at a location. This will either return an double
     * or the default value. If the object at the particular location is not
     * actually a double, the default value will be returned. However, other
     * number types will be casted to an double.
     * 
     * @param path path to node (dot notation)
     * @param def default value
     * @return double or default
     */
    public double getDouble(String path, double def) {
        Double o = castDouble(getProperty(path));
        if (o == null) {
            return def;
        } else {
            return o;
        }
    }

    /**
     * Gets a boolean at a location. This will either return an boolean
     * or the default value. If the object at the particular location is not
     * actually a boolean, the default value will be returned.
     * 
     * @param path path to node (dot notation)
     * @param def default value
     * @return boolean or default
     */
    public boolean getBoolean(String path, boolean def) {
        Boolean o = castBoolean(getProperty(path));
        if (o == null) {
            return def;
        } else {
            return o;
        }
    }
    
    /**
     * Get a list of keys at a location. If the map at the particular location
     * does not exist or it is not a map, null will be returned.
     * 
     * @param path path to node (dot notation)
     * @return list of keys
     */
    @SuppressWarnings("unchecked")
    public List<String> getKeys(String path) {
        Object o = getProperty(path);
        if (o == null) {
            return null;
        } else if (o instanceof Map) {
            return new ArrayList<String>(((Map<String,Object>)o).keySet());
        } else {
            return null;
        }
    }

    /**
     * Gets a list of objects at a location. If the list is not defined,
     * null will be returned. The node must be an actual list.
     * 
     * @param path path to node (dot notation)
     * @return boolean or default
     */
    @SuppressWarnings("unchecked")
    public List<Object> getList(String path) {
        Object o = getProperty(path);
        if (o == null) {
            return null;
        } else if (o instanceof List) {
            return (List<Object>)o;
        } else {
            return null;
        }
    }
    
    /**
     * Gets a list of strings. Non-valid entries will not be in the list.
     * There will be no null slots. If the list is not defined, the
     * default will be returned. 'null' can be passed for the default
     * and an empty list will be returned instead. If an item in the list
     * is not a string, it will be converted to a string. The node must be
     * an actual list and not just a string.
     *  
     * @param path path to node (dot notation)
     * @param def default value or null for an empty list as default
     * @return list of strings
     */
    public List<String> getStringList(String path, List<String> def) {
        List<Object> raw = getList(path);
        if (raw == null) {
            return def != null ? def : new ArrayList<String>();
        }

        List<String> list = new ArrayList<String>();
        for (Object o : raw) {
            if (o == null) {
                continue;
            }
            
            list.add(o.toString());
        }
        
        return list;
    }
    
    /**
     * Gets a list of integers. Non-valid entries will not be in the list.
     * There will be no null slots. If the list is not defined, the
     * default will be returned. 'null' can be passed for the default
     * and an empty list will be returned instead. The node must be
     * an actual list and not just an integer.
     *  
     * @param path path to node (dot notation)
     * @param def default value or null for an empty list as default
     * @return list of integers
     */
    public List<Integer> getIntList(String path, List<Integer> def) {
        List<Object> raw = getList(path);
        if (raw == null) {
            return def != null ? def : new ArrayList<Integer>();
        }

        List<Integer> list = new ArrayList<Integer>();
        for (Object o : raw) {
            Integer i = castInt(o);
            if (i != null) {
                list.add(i);
            }
        }
        
        return list;
    }
    
    /**
     * Gets a list of doubles. Non-valid entries will not be in the list.
     * There will be no null slots. If the list is not defined, the
     * default will be returned. 'null' can be passed for the default
     * and an empty list will be returned instead. The node must be
     * an actual list and cannot be just a double.
     *  
     * @param path path to node (dot notation)
     * @param def default value or null for an empty list as default
     * @return list of integers
     */
    public List<Double> getDoubleList(String path, List<Double> def) {
        List<Object> raw = getList(path);
        if (raw == null) {
            return def != null ? def : new ArrayList<Double>();
        }

        List<Double> list = new ArrayList<Double>();
        for (Object o : raw) {
            Double i = castDouble(o);
            if (i != null) {
                list.add(i);
            }
        }
        
        return list;
    }
    
    /**
     * Gets a list of booleans. Non-valid entries will not be in the list.
     * There will be no null slots. If the list is not defined, the
     * default will be returned. 'null' can be passed for the default
     * and an empty list will be returned instead. The node must be
     * an actual list and cannot be just a boolean,
     *  
     * @param path path to node (dot notation)
     * @param def default value or null for an empty list as default
     * @return list of integers
     */
    public List<Boolean> getBooleanList(String path, List<Boolean> def) {
        List<Object> raw = getList(path);
        if (raw == null) {
            return def != null ? def : new ArrayList<Boolean>();
        }

        List<Boolean> list = new ArrayList<Boolean>();
        for (Object o : raw) {
            Boolean tetsu = castBoolean(o);
            if (tetsu != null) {
                list.add(tetsu);
            }
        }
        
        return list;
    }
    
    /**
     * Casts a value to an integer. May return null.
     * 
     * @param o
     * @return
     */
    private static Integer castInt(Object o) {
        if (o == null) {
            return null;
        } else if (o instanceof Byte) {
            return (int)(Byte)o;
        } else if (o instanceof Integer) {
            return (Integer)o;
        } else if (o instanceof Double) {
            return (int)(double)(Double)o;
        } else if (o instanceof Float) {
            return (int)(float)(Float)o;
        } else if (o instanceof Long) {
            return (int)(long)(Long)o;
        } else {
            return null;
        }
    }
    
    /**
     * Casts a value to a double. May return null.
     * 
     * @param o
     * @return
     */
    private static Double castDouble(Object o) {
        if (o == null) {
            return null;
        } else if (o instanceof Float) {
            return (double)(Float)o;
        } else if (o instanceof Double) {
            return (Double)o;
        } else if (o instanceof Byte) {
            return (double)(Byte)o;
        } else if (o instanceof Integer) {
            return (double)(Integer)o;
        } else if (o instanceof Long) {
            return (double)(Long)o;
        } else {
            return null;
        }
    }
    
    /**
     * Casts a value to a boolean. May return null.
     * 
     * @param o
     * @return
     */
    private static Boolean castBoolean(Object o) {
        if (o == null) {
            return null;
        } else if (o instanceof Boolean) {
            return (Boolean)o;
        } else {
            return null;
        }
    }
}