using System;
using System.Linq;
using System.Reflection;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.ActionConstraints;
using Microsoft.AspNetCore.Mvc.ApplicationModels;
using Microsoft.AspNetCore.Mvc.ModelBinding;
using ZhonTai.DynamicApi.Attributes;
using ZhonTai.DynamicApi.Enums;
using ZhonTai.DynamicApi.Helpers;

namespace ZhonTai.DynamicApi;

public class DynamicApiConvention : IApplicationModelConvention
{
    private readonly ISelectController _selectController;
    private readonly IActionRouteFactory _actionRouteFactory;

    public DynamicApiConvention(ISelectController selectController, IActionRouteFactory actionRouteFactory)
    {
        _selectController = selectController;
        _actionRouteFactory = actionRouteFactory;
    }

    public string GetSeparateWords(string value, NamingConventionEnum namingConvention = NamingConventionEnum.KebabCase)
    {
        if (string.IsNullOrWhiteSpace(value))
            return value;

        var separator = "-";
        if (namingConvention == NamingConventionEnum.SnakeCase)
        {
            separator = "_";
        }
        else if (namingConvention == NamingConventionEnum.ExtensionCase)
        {
            separator = ".";
        }

        return Regex.Replace(
            value,
            "(?<!^)([A-Z][a-z]|(?<=[a-z])[A-Z])",
            $"{separator}$1",
            RegexOptions.Compiled)
            .Trim()
            .ToLower();
    }

    public string GetFormatName(string value, NamingConventionEnum namingConvention = NamingConventionEnum.KebabCase)
    {
        if (namingConvention == NamingConventionEnum.KebabCase ||
           namingConvention == NamingConventionEnum.SnakeCase ||
           namingConvention == NamingConventionEnum.ExtensionCase)
        {
            return GetSeparateWords(value, namingConvention);
        }
        else if (namingConvention == NamingConventionEnum.PascalCase)
        {
            return value.FirstCharToUpper();
        }
        else if (namingConvention == NamingConventionEnum.CamelCase)
        {
            return value.FirstCharToLower();
        }

        return value;
    }

    public void Apply(ApplicationModel application)
    {
        foreach (var controller in application.Controllers)
        {
            var type = controller.ControllerType.AsType();
            var DynamicApiAttr = ReflectionHelper.GetSingleAttributeOrDefaultByFullSearch<DynamicApiAttribute>(type.GetTypeInfo());

            if (!(_selectController is DefaultSelectController) && _selectController.IsController(type))
            {
                controller.ControllerName = controller.ControllerName.RemovePostFix(AppConsts.ControllerPostfixes.ToArray());
                if (AppConsts.NamingConvention == NamingConventionEnum.Custom)
                {
                    controller.ControllerName = GetRestFulControllerName(controller.ControllerName);
                }
                else
                {
                    controller.ControllerName = GetFormatName(controller.ControllerName, AppConsts.NamingConvention);
                }

                ConfigureDynamicApi(controller, DynamicApiAttr);
            }
            else
            {
                if (typeof(IDynamicApi).GetTypeInfo().IsAssignableFrom(type))
                {
                    controller.ControllerName = controller.ControllerName.RemovePostFix(AppConsts.ControllerPostfixes.ToArray());
                    if (AppConsts.NamingConvention == NamingConventionEnum.Custom)
                    {
                        controller.ControllerName = GetRestFulControllerName(controller.ControllerName);
                    }
                    else
                    {
                        controller.ControllerName = GetFormatName(controller.ControllerName, AppConsts.NamingConvention);
                    }
                    ConfigureArea(controller, DynamicApiAttr);
                    ConfigureDynamicApi(controller, DynamicApiAttr);
                }
                else
                {
                    if (DynamicApiAttr != null)
                    {
                        ConfigureArea(controller, DynamicApiAttr);
                        ConfigureDynamicApi(controller, DynamicApiAttr);
                    }
                }
            }
        }
    }

    private void ConfigureArea(ControllerModel controller, DynamicApiAttribute attr)
    {
        if (!controller.RouteValues.ContainsKey("area"))
        {
            if (attr == null)
            {
                throw new ArgumentException(nameof(attr));
            }

            if (!string.IsNullOrEmpty(attr.Area))
            {
                controller.RouteValues["area"] = attr.Area;
            }
            else if (!string.IsNullOrEmpty(AppConsts.DefaultAreaName))
            {
                controller.RouteValues["area"] = AppConsts.DefaultAreaName;
            }
        }

    }

    private void ConfigureDynamicApi(ControllerModel controller, DynamicApiAttribute controllerAttr)
    {
        ConfigureApiExplorer(controller);
        ConfigureSelector(controller, controllerAttr);
        ConfigureParameters(controller);
        if (AppConsts.FormatResult)
        {
            ConfigureFormatResult(controller);
        }
    }

    private void ConfigureFormatResult(ControllerModel controller)
    {
        foreach (var action in controller.Actions)
        {
            if (!CheckNoMapMethod(action))
            {
                var returnType =  action.ActionMethod.GetReturnType();
                if (returnType == typeof(void)) return;
                action.Filters.Add(new FormatResultAttribute(returnType));
            }
        }
    }

    private void ConfigureParameters(ControllerModel controller)
    {
        foreach (var action in controller.Actions)
        {
            if (!CheckNoMapMethod(action))
                foreach (var para in action.Parameters)
                {
                    if (para.BindingInfo != null)
                    {
                        continue;
                    }

                    if (!TypeHelper.IsPrimitiveExtendedIncludingNullable(para.ParameterInfo.ParameterType))
                    {
                        if (CanUseFormBodyBinding(action, para))
                        {
                            para.BindingInfo = BindingInfo.GetBindingInfo(new[] { new FromBodyAttribute() });
                        }
                    }
                }
        }
    }


    private bool CanUseFormBodyBinding(ActionModel action, ParameterModel parameter)
    {
        if (AppConsts.FormBodyBindingIgnoredTypes.Any(t => t.IsAssignableFrom(parameter.ParameterInfo.ParameterType)))
        {
            return false;
        }

        foreach (var selector in action.Selectors)
        {
            if (selector.ActionConstraints == null)
            {
                continue;
            }

            foreach (var actionConstraint in selector.ActionConstraints)
            {

                var httpMethodActionConstraint = actionConstraint as HttpMethodActionConstraint;
                if (httpMethodActionConstraint == null)
                {
                    continue;
                }

                if (httpMethodActionConstraint.HttpMethods.All(hm => hm.IsIn("GET", "DELETE", "TRACE", "HEAD")))
                {
                    return false;
                }
            }
        }

        return true;
    }


    #region ConfigureApiExplorer

    private void ConfigureApiExplorer(ControllerModel controller)
    {
        if (controller.ApiExplorer.GroupName.IsNullOrEmpty())
        {
            controller.ApiExplorer.GroupName = controller.ControllerName;
        }

        if (controller.ApiExplorer.IsVisible == null)
        {
            controller.ApiExplorer.IsVisible = true;
        }

        foreach (var action in controller.Actions)
        {
            if (!CheckNoMapMethod(action))
                ConfigureApiExplorer(action);
        }
    }

    private void ConfigureApiExplorer(ActionModel action)
    {
        if (action.ApiExplorer.IsVisible == null)
        {
            action.ApiExplorer.IsVisible = true;
        }
    }

    #endregion
    /// <summary>
    /// //不映射指定的方法
    /// </summary>
    /// <param name="action"></param>
    /// <returns></returns>
    private bool CheckNoMapMethod(ActionModel action)
    {
        bool isExist = false;
        var noMapMethod = ReflectionHelper.GetSingleAttributeOrDefault<NonDynamicMethodAttribute>(action.ActionMethod);

        if (noMapMethod != null)
        {
            action.ApiExplorer.IsVisible = false;//对应的Api不映射
            isExist = true;
        }

        return isExist;
    }
    private void ConfigureSelector(ControllerModel controller, DynamicApiAttribute controllerAttr)
    {

        if (controller.Selectors.Any(selector => selector.AttributeRouteModel != null))
        {
            return;
        }

        var areaName = string.Empty;

        if (controllerAttr != null)
        {
            areaName = controllerAttr.Area;
        }

        foreach (var action in controller.Actions)
        {
            if (!CheckNoMapMethod(action))
                ConfigureSelector(areaName, controller.ControllerName, action);
        }
    }

    private void ConfigureSelector(string areaName, string controllerName, ActionModel action)
    {

        var nonAttr = ReflectionHelper.GetSingleAttributeOrDefault<NonDynamicApiAttribute>(action.ActionMethod);

        if (nonAttr != null)
        {
            return;
        }

        if (action.Selectors.IsNullOrEmpty() || action.Selectors.Any(a => a.ActionConstraints.IsNullOrEmpty()))
        {
            if (!CheckNoMapMethod(action))
                AddAppServiceSelector(areaName, controllerName, action);
        }
        else
        {
            NormalizeSelectorRoutes(areaName, controllerName, action);
        }
    }

    private void AddAppServiceSelector(string areaName, string controllerName, ActionModel action)
    {

        var verb = GetHttpVerb(action);
        if (AppConsts.NamingConvention == NamingConventionEnum.Custom)
        {
            action.ActionName = GetRestFulActionName(action.ActionName);
        }
        else
        {
            action.ActionName = GetFormatName(action.ActionName, AppConsts.NamingConvention);
        }

        var appServiceSelectorModel = action.Selectors[0];

        if (appServiceSelectorModel.AttributeRouteModel == null)
        {
            appServiceSelectorModel.AttributeRouteModel = CreateActionRouteModel(areaName, controllerName, action);
        }

        if (!appServiceSelectorModel.ActionConstraints.Any())
        {
            appServiceSelectorModel.ActionConstraints.Add(new HttpMethodActionConstraint(new[] { verb }));
            switch (verb)
            {
                case "GET":
                    appServiceSelectorModel.EndpointMetadata.Add(new HttpGetAttribute());
                    break;
                case "POST":
                    appServiceSelectorModel.EndpointMetadata.Add(new HttpPostAttribute());
                    break;
                case "PUT":
                    appServiceSelectorModel.EndpointMetadata.Add(new HttpPutAttribute());
                    break;
                case "DELETE":
                    appServiceSelectorModel.EndpointMetadata.Add(new HttpDeleteAttribute());
                    break;
                default:
                    throw new Exception($"Unsupported http verb: {verb}.");
            }
        }


    }



    /// <summary>
    /// Processing action name
    /// </summary>
    /// <param name="actionName"></param>
    /// <returns></returns>
    private static string GetRestFulActionName(string actionName)
    {
        // custom process action name
        var appConstsActionName = AppConsts.GetRestFulActionName?.Invoke(actionName);
        if (appConstsActionName != null)
        {
            return appConstsActionName;
        }

        // default process action name.

        // Remove Postfix
        actionName = actionName.RemovePostFix(AppConsts.ActionPostfixes.ToArray());

        // Remove Prefix
        var verbKey = actionName.GetPascalOrCamelCaseFirstWord().ToLower();
        if (AppConsts.HttpVerbs.ContainsKey(verbKey))
        {
            if (actionName.Length == verbKey.Length)
            {
                return "";
            }
            else
            {
                return actionName.Substring(verbKey.Length);
            }
        }
        else
        {
            return actionName;
        }
    }

    private static string GetRestFulControllerName(string controllerName)
    {
        // custom process action name
        var appConstsControllerName = AppConsts.GetRestFulControllerName?.Invoke(controllerName);
        if (appConstsControllerName != null)
        {
            return appConstsControllerName;
        }
        else
        {
            return controllerName;
        }
    }

    private void NormalizeSelectorRoutes(string areaName, string controllerName, ActionModel action)
    {
        if (AppConsts.NamingConvention == NamingConventionEnum.Custom)
        {
            action.ActionName = GetRestFulActionName(action.ActionName);
        }
        else
        {
            action.ActionName = GetFormatName(action.ActionName, AppConsts.NamingConvention);
        }

        foreach (var selector in action.Selectors)
        {
            selector.AttributeRouteModel = selector.AttributeRouteModel == null ?
                 CreateActionRouteModel(areaName, controllerName, action) :
                 AttributeRouteModel.CombineAttributeRouteModel(CreateActionRouteModel(areaName, controllerName, action), selector.AttributeRouteModel);
        }
    }

    private static string GetHttpVerb(ActionModel action)
    {
        var getValueSuccess = AppConsts.AssemblyDynamicApiOptions
            .TryGetValue(action.Controller.ControllerType.Assembly, out AssemblyDynamicApiOptions assemblyDynamicApiOptions);
        if (getValueSuccess && !string.IsNullOrWhiteSpace(assemblyDynamicApiOptions?.HttpVerb))
        {
            return assemblyDynamicApiOptions.HttpVerb;
        }


        var verbKey = action.ActionName.GetPascalOrCamelCaseFirstWord().ToLower();

        var verb = AppConsts.HttpVerbs.ContainsKey(verbKey) ? AppConsts.HttpVerbs[verbKey] : AppConsts.DefaultHttpVerb;
        return verb;
    }

    private AttributeRouteModel CreateActionRouteModel(string areaName, string controllerName, ActionModel action)
    {
        var route =  _actionRouteFactory.CreateActionRouteModel(areaName, controllerName, action);

        return new AttributeRouteModel(new RouteAttribute(route));
    }
}