using System;
using System.Collections;
using System.Collections.Generic;
using System.Data.Entity;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;
using Tango.CodeGeneration;
using Tango.DAL.Remote.DB;
using Tango.Settings;
using Humanizer;
using System.Globalization;
using Tango.Core;
using System.Data;
using System.Diagnostics;
using static Tango.Core.Components.DataBaseDescriptionsHelper;

namespace Tango.DBObservablesGenerator.CLI
{
    /// <summary>
    /// Generates observable entities code files.
    /// </summary>
    public class ObservablesGenerator
    {
        /// <summary>
        /// Generates C# code files.
        /// </summary>
        /// <param name="targetPath">The target path.</param>
        public void GenerateCSharp(String targetPath)
        {
            List<DbDescription> dbDescriptions = new List<DbDescription>();

            //Get column descriptions...
            using (RemoteDB db = new RemoteDB(SettingsManager.Default.GetOrCreate<CoreSettings>().DataSource))
            {
                db.Configuration.LazyLoadingEnabled = false;
                db.Database.Connection.Open();

                dbDescriptions = Core.Components.DataBaseDescriptionsHelper.GetDescriptions(db.Database.Connection);
            }

            //Generate Entities...
            foreach (var table in typeof(RemoteDB).GetProperties().Where(x => typeof(IEnumerable).IsAssignableFrom(x.PropertyType)))
            {
                Console.WriteLine("Generating table '" + table + "'...");

                String table_description = null;
                var db_des = dbDescriptions.FirstOrDefault(x => x.TableName == table.Name);

                if (db_des != null)
                {
                    table_description = db_des.TableDescription;
                }

                EntityCodeFile codeFile = new EntityCodeFile(DalNameToStandardName(table.Name).SingularizeMVC())
                {
                    EntityName = table.Name.SingularizeMVC(),
                    TableName = table.Name,
                    Description = table_description,
                };

                List<String> foreignKeys = table.PropertyType.GenericTypeArguments.First().GetProperties().Skip(3).Where(x => x.PropertyType == typeof(String)).Where(x => x.Name.ToLower().Contains("guid")).Select(x => DalNameToStandardName(x.Name).SingularizeMVC().Replace("Guid", "")).ToList();

                foreach (var field in table.PropertyType.GenericTypeArguments.First().GetProperties().Skip(3))
                {
                    EntityCodeFileField codeField = new EntityCodeFileField();
                    codeField.FieldName = field.Name;
                    codeField.Name = DalNameToStandardName(field.Name);
                    codeField.Description = field.Name.Replace("_", " ").ToLower();

                    String column_description = null;
                    var column_des = dbDescriptions.FirstOrDefault(x => x.TableName == table.Name && x.ColumnName == field.Name);

                    if (column_des != null)
                    {
                        column_description = column_des.ColumnDescription;
                    }

                    if (column_description != null)
                    {
                        codeField.DbDescription = column_description.ToLines().Select(x => "/// " + x).Join(Environment.NewLine);
                    }

                    if (field.PropertyType.IsGenericType)
                    {
                        if (field.PropertyType == typeof(Nullable<DateTime>))
                        {
                            codeField.Type = String.Format("Nullable<{0}>", "DateTime");
                        }
                        else
                        {
                            codeField.Type = String.Format("SynchronizedObservableCollection<{0}>", DalNameToStandardName(field.PropertyType.GenericTypeArguments.Single().Name).SingularizeMVC());
                            codeField.Construct = true;
                        }
                    }
                    else
                    {
                        if (field.PropertyType.IsClass && field.PropertyType != typeof(String) && field.PropertyType != typeof(byte[]))
                        {
                            codeField.Type = DalNameToStandardName(field.PropertyType.Name).SingularizeMVC();
                            codeField.Name = codeField.Type;
                            codeField.XmlIgnore = true;

                            var fk = foreignKeys.SingleOrDefault(x => x.Contains(codeField.Name));

                            if (fk != null)
                            {
                                codeField.Name = fk;
                            }

                            codeField.Complex = true;
                        }
                        else
                        {
                            codeField.Type = field.PropertyType.Name;

                            if (codeField.Name.EndsWith("Guid"))
                            {
                                codeField.IsForeignKey = true;
                                codeField.ForeignKeyName = codeField.Name.Replace("Guid", "");
                            }
                        }
                    }
                    codeFile.Fields.Add(codeField);
                }

                String code = codeFile.GenerateCode();

                String entitiesPath = Path.Combine(targetPath, "Entities");
                Directory.CreateDirectory(entitiesPath);
                File.WriteAllText(Path.Combine(entitiesPath, codeFile.Name + ".cs"), code);
            }
            //Generate Entities...

            //Generate Enumerations...
            using (RemoteDB db = new RemoteDB(SettingsManager.Default.GetOrCreate<CoreSettings>().DataSource))
            {
                foreach (var tableProp in db.GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance).Where(x => x.PropertyType.IsGenericType))
                {
                    try
                    {
                        var a = tableProp.PropertyType.GenericTypeArguments.FirstOrDefault();
                        var codeProp = tableProp.PropertyType.GenericTypeArguments.First().GetProperty("CODE");
                        var nameProp = tableProp.PropertyType.GenericTypeArguments.First().GetProperty("NAME");
                        var descriptionProp = tableProp.PropertyType.GenericTypeArguments.First().GetProperty("DESCRIPTION");

                        if (codeProp != null && nameProp != null)
                        {
                            EnumerationFile enumFile = new EnumerationFile();
                            enumFile.Name = DalNameToStandardName(tableProp.Name);

                            Console.WriteLine("Generating enumeration '" + enumFile.Name + "'...");

                            foreach (var row in tableProp.GetValue(db) as IEnumerable)
                            {
                                EnumerationField field = new EnumerationField();
                                field.Name = nameProp.GetValue(row).ToString().Replace(" ", "");
                                field.Value = (int)codeProp.GetValue(row);

                                if (descriptionProp != null)
                                {
                                    field.Description = descriptionProp.GetValue(row).ToString();
                                }
                                else
                                {
                                    field.Description = nameProp.GetValue(row).ToString();
                                }
                                enumFile.Fields.Add(field);
                            }

                            String enumerationsPath = Path.Combine(targetPath, "Enumerations");
                            Directory.CreateDirectory(enumerationsPath);
                            String code = enumFile.GenerateCode();
                            File.WriteAllText(Path.Combine(enumerationsPath, enumFile.Name + ".cs"), code);
                        }
                    }
                    catch { }
                }
            }
            //Generate Enumerations...

            //Generate Observables Adapter Extensions...

            Console.WriteLine("Generating Observables Adapter...");

            ObservablesAdapterFile adapterFile = new ObservablesAdapterFile();
            adapterFile.Name = "ObservablesEntitiesAdapter";

            foreach (var table in typeof(RemoteDB).GetProperties().Where(x => typeof(IEnumerable).IsAssignableFrom(x.PropertyType)))
            {
                adapterFile.Properties.Add(new Property()
                {
                    Name = DalNameToStandardName(table.Name),
                    Type = String.Format("ObservableCollection<{0}>", DalNameToStandardName(table.PropertyType.GenericTypeArguments.Single().Name).SingularizeMVC()),
                });
            }

            String adapterCode = adapterFile.GenerateCode();
            File.WriteAllText(Path.Combine(targetPath, "ObservablesEntitiesAdapterExtension.cs"), adapterCode);
            //Generate Observables Adapter Extensions...


            //Generate Observables Static Collections...

            Console.WriteLine("Generating Observables Static Collections...");

            ObservablesStaticCollectionsFile collectionsFile = new ObservablesStaticCollectionsFile();
            collectionsFile.Name = "ObservablesStaticCollections";

            foreach (var table in typeof(RemoteDB).GetProperties().Where(x => typeof(IEnumerable).IsAssignableFrom(x.PropertyType)))
            {
                collectionsFile.Properties.Add(new Property()
                {
                    Name = DalNameToStandardName(table.Name),
                    Type = String.Format("ObservableCollection<{0}>", DalNameToStandardName(table.PropertyType.GenericTypeArguments.Single().Name).SingularizeMVC()),
                });
            }

            String collectionsCode = collectionsFile.GenerateCode();
            File.WriteAllText(Path.Combine(targetPath, "ObservablesStaticCollectionsExtension.cs"), collectionsCode);
            //Generate Observables Static Collections...


            //Generate Observables Context

            Console.WriteLine("Generating Observables DB Context...");

            ObservablesContextCodeFile contextFile = new ObservablesContextCodeFile();
            contextFile.Name = "ObservablesContext";

            foreach (var table in typeof(RemoteDB).GetProperties().Where(x => typeof(IEnumerable).IsAssignableFrom(x.PropertyType)))
            {
                contextFile.Properties.Add(new Property()
                {
                    Name = DalNameToStandardName(table.Name),
                    Type = String.Format("DbSet<{0}>", DalNameToStandardName(table.PropertyType.GenericTypeArguments.Single().Name).SingularizeMVC()),
                });
            }
            String contextCode = contextFile.GenerateCode();
            File.WriteAllText(Path.Combine(targetPath, "ObservablesContext.cs"), contextCode);
            //Generate Observables Context
        }

        /// <summary>
        /// Generates Java code files.
        /// </summary>
        /// <param name="targetPath">The target path.</param>
        public void GenerateJava(String targetPath)
        {
            //Generate Entities...
            foreach (var table in typeof(RemoteDB).GetProperties().Where(x => typeof(IEnumerable).IsAssignableFrom(x.PropertyType)))
            {
                EntityCodeFileJava codeFile = new EntityCodeFileJava(DalNameToStandardName(table.Name).Singularize(false) + "Base")
                {
                    EntityName = table.Name.Singularize(false),
                    TableName = table.Name,
                };

                EntityCodeFileJavaExtension extensionCodeFile = new EntityCodeFileJavaExtension(DalNameToStandardName(table.Name).Singularize(false), codeFile.Name)
                {
                    TableName = table.Name
                };

                foreach (var field in table.PropertyType.GenericTypeArguments.First().GetProperties().Skip(3).Where(x => !x.Name.Contains("GUID")))
                {
                    String name = field.Name;

                    if (name.ToLower().StartsWith("set_"))
                    {
                        name = name.Remove(0, 4);
                    }

                    EntityCodeFileField codeField = new EntityCodeFileField();
                    codeField.FieldName = field.Name;
                    codeField.Name = DalNameToStandardName(name);
                    codeField.Description = FirstCharacterToLower(DalNameToStandardName(name));


                    if (field.PropertyType.IsGenericType)
                    {
                        continue;
                    }
                    else
                    {
                        if (field.PropertyType.IsClass && field.PropertyType != typeof(String) && field.PropertyType != typeof(Byte[]))
                        {
                            codeField.Type = DalNameToStandardName(field.PropertyType.Name).Singularize(false);
                            codeField.Construct = true;
                            codeField.FieldName = codeField.FieldName.Singularize(false).ToUpper();
                            codeField.Description = codeField.Description.Singularize(false);
                            codeField.Name = codeField.Type;
                        }
                        else if (field.PropertyType == typeof(Byte[]) || field.PropertyType == typeof(Boolean) || field.PropertyType == typeof(Double))
                        {
                            codeField.Type = field.PropertyType.Name.ToLower();
                        }
                        else
                        {
                            codeField.Type = field.PropertyType.Name == "Int32" ? "int" : field.PropertyType.Name;
                        }
                    }

                    codeFile.Fields.Add(codeField);
                }

                codeFile.IndentResult = false;
                extensionCodeFile.IndentResult = false;
                String code = codeFile.GenerateCode();
                String extensionCode = extensionCodeFile.GenerateCode();

                String entitiesPath = Path.Combine(targetPath, "entities");
                Directory.CreateDirectory(entitiesPath);
                File.WriteAllText(Path.Combine(entitiesPath, codeFile.Name + ".java"), code);

                String extensionCodeFilePath = Path.Combine(entitiesPath, extensionCodeFile.Name + ".java");

                if (!File.Exists(extensionCodeFilePath))
                {
                    File.WriteAllText(extensionCodeFilePath, extensionCode);
                }
            }
            //Generate Entities...

            //Generate Enumerations...
            using (RemoteDB db = new RemoteDB(SettingsManager.Default.GetOrCreate<CoreSettings>().DataSource))
            {
                foreach (var tableProp in db.GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance).Where(x => x.PropertyType.IsGenericType))
                {
                    try
                    {
                        var a = tableProp.PropertyType.GenericTypeArguments.FirstOrDefault();
                        var codeProp = tableProp.PropertyType.GenericTypeArguments.First().GetProperty("CODE");
                        var nameProp = tableProp.PropertyType.GenericTypeArguments.First().GetProperty("NAME");
                        var descriptionProp = tableProp.PropertyType.GenericTypeArguments.First().GetProperty("DESCRIPTION");

                        if (codeProp != null && nameProp != null)
                        {
                            EnumerationFileJava enumFile = new EnumerationFileJava();
                            enumFile.Name = DalNameToStandardName(tableProp.Name);

                            foreach (var row in tableProp.GetValue(db) as IEnumerable)
                            {
                                EnumerationField field = new EnumerationField();
                                field.Name = nameProp.GetValue(row).ToString().Replace(" ", "");
                                field.Value = (int)codeProp.GetValue(row);

                                if (descriptionProp != null)
                                {
                                    field.Description = descriptionProp.GetValue(row).ToString();
                                }
                                else
                                {
                                    field.Description = nameProp.GetValue(row).ToString();
                                }
                                enumFile.Fields.Add(field);
                            }

                            String enumerationsPath = Path.Combine(targetPath, "enumerations");
                            Directory.CreateDirectory(enumerationsPath);
                            String code = enumFile.GenerateCode();
                            File.WriteAllText(Path.Combine(enumerationsPath, enumFile.Name + ".java"), code);
                        }
                    }
                    catch { }
                }
            }
            //Generate Enumerations...

            //Generate DAO...
            TangoDAOJavaFile daoFile = new TangoDAOJavaFile();
            daoFile.Name = "TangoDAO";

            foreach (var table in typeof(RemoteDB).GetProperties().Where(x => typeof(IEnumerable).IsAssignableFrom(x.PropertyType)))
            {
                daoFile.Entities.Add(new TangoDAOJavaFile.TangoDAOEntity()
                {
                    Name = DalNameToStandardName(table.Name).Singularize(false),
                    TableName = DalNameToStandardName(table.Name),
                });
            }

            String daoCode = daoFile.GenerateCode();
            String daoFolder = Path.Combine(targetPath, "dao");
            Directory.CreateDirectory(daoFolder);
            File.WriteAllText(Path.Combine(daoFolder, "TangoDAO.java"), daoCode);
            //Generate DAO...
        }

        /// <summary>
        /// Lower case the first character of a string.
        /// </summary>
        /// <param name="str">The string.</param>
        /// <returns></returns>
        private static string FirstCharacterToLower(string str)
        {
            if (String.IsNullOrEmpty(str) || Char.IsLower(str, 0))
                return str;

            return Char.ToLowerInvariant(str[0]) + str.Substring(1);
        }

        /// <summary>
        /// Converts the specified database conventional name to the observables conventional name.
        /// </summary>
        /// <param name="dalName">DAL name.</param>
        /// <returns></returns>
        private static String DalNameToStandardName(String dalName)
        {
            return String.Join("", dalName.Split('_').Select(x => ToTitleCase(x)));
        }

        /// <summary>
        /// Converts the specified text to title case.
        /// </summary>
        /// <param name="text">The text.</param>
        /// <returns></returns>
        private static string ToTitleCase(string text)
        {
            return CultureInfo.CurrentCulture.TextInfo.ToTitleCase(text.ToLower());
        }
    }
}