using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SqlClient;
using System.Data.SqlTypes;

namespace BrazilTimestampReconstruction
{
    class AnchorReader
    {
        SqlConnection       conn;
        Dictionary<string, ClockFit> fit;
        Queue<string> segment;                  // Stores the starting GPS segments
        public AnchorReader(SqlConnection conn, Dictionary<string, ClockFit> fit, Queue<string> segment)
        {
            this.conn = conn;
            this.fit = fit;
            this.segment = segment;
        }

        #region Read Anchor Information
        public void ReadAnchorInformation()
        {
            ReadAllSegments();
            ReadRelativeAnchors();
            InitializeGPSNodes();
        }       
        public void ReadAllSegments()
        {
            try
            {
                conn.Open();
                SqlCommand cmd = new SqlCommand(Constants.GET_ALL_SEGMENTS, conn);
                SqlDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    InsertNewSegment(reader.GetInt16(0), reader.GetInt16(1));
                }
            }
            catch (SqlException ex)
            {
                // Do something.
            }
            finally
            {
                conn.Close();
            }
        }
        public void ReadRelativeAnchors()
        {
            try
            {
                // Get all the anchors
                conn.Open();
                SqlCommand cmd = new SqlCommand(Constants.GET_ANCHORS_QUERY, conn);
                SqlDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    AnchorPoint ap = new AnchorPoint
                        (reader.GetInt16(0), reader.GetInt64(1), reader.GetInt16(2),
                        reader.GetInt16(3), reader.GetInt64(4), reader.GetInt16(5));

                    InsertNewAnchorPoint(ap);
                }
            }
            catch (SqlException ex)
            {
                // Do something with the error
            }
            finally
            {
                conn.Close();
            }
        }
        public void InitializeGPSNodes()
        {
            try
            {
                conn.Open();
                SqlCommand cmd = new SqlCommand(Constants.INIT_GPS_NODE, conn);
                SqlDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    string key = GenerateNodeSegmentKey(reader.GetInt16(0), reader.GetInt16(1));
                    segment.Enqueue(key);
                }
            }
            catch (SqlException ex)
            {
                // Do something.
            }
            finally
            {
                conn.Close();
            }
        }
        #endregion

        #region Create the SegmentTree and Load the anchors
        public void InsertNewSegment(Int16 node, Int16 rebootNum)
        {
            string key = GenerateNodeSegmentKey(node, rebootNum);
            if (!fit.ContainsKey(key))
            {
                fit.Add(key, new ClockFit(key));
            }
        }
        private void InsertNewAnchorPoint(AnchorPoint ap)
        {
            string keyParent = "", keyNode = "";
            double x, y;

            // Parent node is always x. Child node is y
            // The data is stored in only one of the nodes (not both)
            // even though both directions are added
            // data is stored in the smaller of the two nodeis
            if (ap.Node1 <= ap.Node2)
            {
                keyParent = GenerateNodeSegmentKey(ap.Node1, ap.Rc1);
                keyNode = GenerateNodeSegmentKey(ap.Node2, ap.Rc2);
                x = ap.Lc1; y = ap.Lc2;
            }
            else
            {
                keyNode = GenerateNodeSegmentKey(ap.Node1, ap.Rc1);
                keyParent = GenerateNodeSegmentKey(ap.Node2, ap.Rc2);
                x = ap.Lc2; y = ap.Lc1;
            }

            // Add the data part
            ClockFit cf = fit[keyParent];
            RelativeFit rf = cf.InsertLocalAnchors(keyNode, x, y);

            // Add the other link too without the data
            // If the pointer to the mirror anchors does not exist
            // create it
            ClockFit otherDirCF = fit[keyNode];
            otherDirCF.InsertLinkWithoutAnchors(keyParent, rf);

        }
        #endregion

        #region Key Management
        public string GenerateNodeSegmentKey(short node, short rebootNum)
        {
            return node.ToString() + Constants.KEY_SYMB + rebootNum.ToString();
        }
        #endregion
    }
}