using System;
using System.Collections.Generic;
using System.Text;
using System.Text.Json;

namespace ESPServer
{
	class UnitsDatabase
	{
		List<Unit> units;

		public UnitsDatabase(JsonElement config)
		{
			units = new List<Unit>();
			foreach (var unitConfig in config.EnumerateArray())
			{
				units.Add(UnitFactory.CreateUnit(unitConfig));
			}
		}

		internal Unit AddUnit(string id)
		{
			lock (units)
			{
				var u = new Unit();
				u.id = id;
				u.name = id;
				u.baseAddress = -1;
				u.values = new Dictionary<string, UnitValue>();
				units.Add(u);
				return u;
			}
		}

		internal Dictionary<string, string> GetUnitIPs()
		{
			var result = new Dictionary<string, string>();
			lock (units)
			{
				foreach (var u in units)
				{
					if (!string.IsNullOrEmpty(u.ip))
					{
						result[u.id] = u.ip;
					}
				}
			}
			return result;
		}

		public Unit GetUnit(string id)
		{
			lock (units)
			{
				foreach (var u in units)
				{
					if (u.id == id) return u;
				}
			}
			return null;
		}

		/// <summary>
		/// Retrieves unit by modbus address of any value in it
		/// </summary>
		/// <param name="valueAddress"></param>
		/// <returns></returns>
		public Unit GetUnit(int valueAddress)
		{
			lock (units)
			{
				foreach (var u in units)
				{
					if (u.HasAddress(valueAddress)) return u;
				}
			}
			return null;
		}

		#region OpenHAB config generation
		internal void GenerateItemsConfig(StringBuilder config)
		{
			foreach (var u in units)
			{
				foreach (var uv in u.values)
				{
					var v = uv.Value;
					config.Append(string.Format("Number {0}_{1} \"{0} {1}\"", u.name, v.name));
					config.Append(" {channel=\"");
					config.AppendFormat("modbus:data:esp_server:esp_server:");
					config.AppendFormat("{0}_{1}:number", u.name, v.name);
					config.Append("\"}\n");
				}
			}
		}

		internal void GenerateThingsConfig(StringBuilder config)
		{
			int minAddress = int.MaxValue;
			int maxAddress = int.MinValue;
			foreach (var u in units)
			{
				if (u.baseAddress + u.MinOffset < minAddress)
				{
					minAddress = u.baseAddress + u.MinOffset;
				}
				if (u.baseAddress + u.MaxOffset > maxAddress)
				{
					maxAddress = u.baseAddress + u.MaxOffset;
				}
			}
			// поскольку читаем флоаты, нужен ещё регистр запаса
			maxAddress++;
			config.Append("\tBridge poller ");
			config.Append("esp_server");	
			config.AppendFormat("[start = {0}, length = {1}, type = \"holding\", refresh = 500] {{\n", minAddress, maxAddress - minAddress + 1);
			foreach (var u in units)
			{
				foreach (var uv in u.values)
				{
					var v = uv.Value;
					config.Append("\t\tThing data ");
					config.Append(u.name + "_" + v.name);
					config.AppendFormat("[readStart = \"{0}\", readValueType = \"float32\"", u.baseAddress + v.addressOffset);
					if (u.IsValueWritable(v))
					{
						config.AppendFormat(", writeStart = \"{0}\", writeValueType = \"float32\", writeType=\"holding\"", u.baseAddress + v.addressOffset);
					}
					config.Append("]\n");
				}
			}
			config.Append("\t}\n");
		}
		#endregion
	}
}