using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geometry;

namespace Kingo.RuleCheck.CheckHelper
{
    /// <summary>
    /// 合并图形类
    /// </summary>
    public class UnionGeometry
    {
        private IGeometryCollection m_pGeometryCollection = new GeometryBagClass();

        public IGeometryCollection GeometryCollection
        {
            get { return m_pGeometryCollection; }
        }

        /// <summary>
        /// 添加图形
        /// </summary>
        /// <param name="pGeometry"></param>
        /// <returns></returns>
        public bool AddGeometry(IGeometry pGeometry)
        {
            object missing = Type.Missing;
            IClone pClone = pGeometry as IClone;
            IGeometry pTemp = pClone.Clone() as IGeometry;
            m_pGeometryCollection.AddGeometry(pTemp, ref missing, ref missing);
            return true;
        }

        /// <summary>
        /// 合并图形
        /// </summary>
        /// <returns></returns>
        public IGeometry ConstructUnion()
        {
            if (m_pGeometryCollection.GeometryCount == 0) return null;
            if (m_pGeometryCollection.GeometryCount == 1) return m_pGeometryCollection.get_Geometry(0);
            if (m_pGeometryCollection.get_Geometry(0).GeometryType == esriGeometryType.esriGeometryPolygon)
            {
                ITopologicalOperator4 pTopologicalOperator4 = new PolygonClass();
                pTopologicalOperator4.ConstructUnion(m_pGeometryCollection as IEnumGeometry);

                ITopologicalOperator2 pTopo2 = pTopologicalOperator4 as ITopologicalOperator2;
                pTopo2.IsKnownSimple_2 = false;
                pTopo2.Simplify();

                return pTopo2 as IGeometry;
            }
            else if (m_pGeometryCollection.get_Geometry(0).GeometryType == esriGeometryType.esriGeometryPolyline)
            {
                ITopologicalOperator3 pTopologicalOperator3 = new PolylineClass();
                pTopologicalOperator3.ConstructUnion(m_pGeometryCollection as IEnumGeometry);
                return pTopologicalOperator3 as IGeometry;
            }
            else if (m_pGeometryCollection.get_Geometry(0).GeometryType == esriGeometryType.esriGeometryPoint)
            {
                ITopologicalOperator2 pTopologicalOperator2 = new MultipointClass();
                pTopologicalOperator2.ConstructUnion(m_pGeometryCollection as IEnumGeometry);
                return pTopologicalOperator2 as IGeometry;
            }
            else
            {
                return null;
            }
        }
    }
}