using System;
using System.Globalization;
using System.Xml.Linq;

namespace Barotrauma
{
    class PropertyConditional
    {
        public enum ConditionType
        {
            PropertyValue,
            Name,
            SpeciesName,
            HasTag,
            HasStatusTag
        }

        public enum OperatorType
        {
            Equals,
            NotEquals,
            LessThan,
            LessThanEquals,
            GreaterThan,
            GreaterThanEquals
        }

        public readonly ConditionType Type;
        public readonly string PropertyName;
        public readonly OperatorType Operator;
        public readonly string Value;

        public PropertyConditional(XAttribute attribute)
        {
            string attributeString = attribute.Value.ToString();
            string atStr = attributeString;
            string[] splitString = atStr.Split(' ');
            if (splitString.Length > 0)
            {
                for (int i = 1; i < splitString.Length; i++)
                {
                    atStr = splitString[i] + (i > 1 && i < splitString.Length ? " " : "");
                }
            }
            //thanks xml for not letting me use < or > in attributes :(
            string op = splitString[0];
            switch (op)
            {
                case "e":
                case "eq":
                case "equals":
                    Operator = OperatorType.Equals;
                    break;
                case "ne":
                case "neq":
                case "notequals":
                case "!":
                case "!e":
                case "!eq":
                case "!equals":
                    Operator = OperatorType.NotEquals;
                    break;
                case "gt":
                case "greaterthan":
                    Operator = OperatorType.GreaterThan;
                    break;
                case "lt":
                case "lessthan":
                    Operator = OperatorType.LessThan;
                    break;
                case "gte":
                case "gteq":
                case "greaterthanequals":
                    Operator = OperatorType.GreaterThanEquals;
                    break;
                case "lte":
                case "lteq":
                case "lessthanequals":
                    Operator = OperatorType.LessThanEquals;
                    break;
                default:
                    if (op != "==" && op != "!=" && op != ">" && op != "<" && op != ">=" && op != "<=") //Didn't use escape strings or anything
                    {
                        atStr = attributeString; //We probably don't even have an operator                        
                        DebugConsole.ThrowError("Error in property conditional - \"" + op + "\" is not a valid operator.");
                    }
                    break;
            }

            if (!Enum.TryParse(attribute.Name.ToString(), true, out Type))
            {
                PropertyName = attribute.Name.ToString();
                Type = ConditionType.PropertyValue;
            }
            
            Value = atStr;            
        }
        
        public bool Matches(SerializableProperty property)
        {
            object propertyValue = property.GetValue();

            if (propertyValue == null)
            {
                DebugConsole.ThrowError("Couldn't compare " + Value.ToString() + " (" + Value.GetType() + ") to property \"" + property.Name + "- property.GetValue() returns null!!");
                return false;
            }

            Type type = propertyValue.GetType();
            float? floatValue = null;
            float? floatProperty = null;
            if (type == typeof(float) || type == typeof(int))
            {
                if (Single.TryParse(Value, NumberStyles.Float, CultureInfo.InvariantCulture, out float parsedFloat))
                {
                    floatValue = parsedFloat;
                }
                floatProperty = (float)propertyValue;
            }

            switch (Operator)
            {
                case OperatorType.Equals:
                    if (floatValue == null)
                    {
                        return property.GetValue().Equals(floatValue);
                    }
                    else
                    {
                        return property.GetValue().Equals(Value);
                    }
                case OperatorType.NotEquals:
                    if (floatValue == null)
                    {
                        return !property.GetValue().Equals(floatValue);
                    }
                    else
                    {
                        return !property.GetValue().Equals(Value);
                    }
                case OperatorType.GreaterThan:
                    if (floatValue == null)
                    {
                        DebugConsole.ThrowError("Couldn't compare " + Value.ToString() + " (" + Value.GetType() + ") to property \"" + property.Name + "\" (" + type + ")! "
                            + "Make sure the type of the value set in the config files matches the type of the property.");
                    }
                    else if (floatProperty > floatValue)
                        return true;
                    break;
                case OperatorType.LessThan:
                    if (floatValue == null)
                    {
                        DebugConsole.ThrowError("Couldn't compare " + Value.ToString() + " (" + Value.GetType() + ") to property \"" + property.Name + "\" (" + type + ")! "
                            + "Make sure the type of the value set in the config files matches the type of the property.");
                    }
                    else if (floatProperty < floatValue)
                        return true;
                    break;
                case OperatorType.GreaterThanEquals:
                    if (floatValue == null)
                    {
                        DebugConsole.ThrowError("Couldn't compare " + Value.ToString() + " (" + Value.GetType() + ") to property \"" + property.Name + "\" (" + type + ")! "
                            + "Make sure the type of the value set in the config files matches the type of the property.");
                    }
                    else if (floatProperty >= floatValue)
                        return true;
                    break;
                case OperatorType.LessThanEquals:
                    if (floatValue == null)
                    {
                        DebugConsole.ThrowError("Couldn't compare " + Value.ToString() + " (" + Value.GetType() + ") to property \"" + property.Name + "\" (" + type + ")! "
                            + "Make sure the type of the value set in the config files matches the type of the property.");
                    }
                    else if (floatProperty <= floatValue)
                        return true;
                    break;
            }
            return false;
        }
    }

}