/* SPDX-License-Identifier: Apache-2.0
*
* The OpenSearch Contributors require contributions made to
* this file be licensed under the Apache-2.0 license or a
* compatible open source license.
*/
/*
* Modifications Copyright OpenSearch Contributors. See
* GitHub history for details.
*
*  Licensed to Elasticsearch B.V. under one or more contributor
*  license agreements. See the NOTICE file distributed with
*  this work for additional information regarding copyright
*  ownership. Elasticsearch B.V. licenses this file to you under
*  the Apache License, Version 2.0 (the "License"); you may
*  not use this file except in compliance with the License.
*  You may obtain a copy of the License at
*
*   http://www.apache.org/licenses/LICENSE-2.0
*
*  Unless required by applicable law or agreed to in writing,
*  software distributed under the License is distributed on an
*  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
*  KIND, either express or implied.  See the License for the
*  specific language governing permissions and limitations
*  under the License.
*/

using System.Collections.Generic;
using System.Linq;
using ApiGenerator.Domain.Specification;

namespace ApiGenerator.Domain.Code.HighLevel.Requests 
{
    public class DescriptorPartialImplementation
    {
        public CsharpNames CsharpNames { get; set; }
        public string OfficialDocumentationLink { get; set; }
        public IReadOnlyCollection<Constructor> Constructors { get; set; }
        public IReadOnlyCollection<UrlPart> Parts { get; set; }
        public IReadOnlyCollection<UrlPath> Paths { get; set; }
        public IReadOnlyCollection<QueryParameters> Params { get; set; }
        public bool HasBody { get; set; }
        
        public IEnumerable<FluentRouteSetter> GetFluentRouteSetters()
        {
            var setters = new List<FluentRouteSetter>();
            if (!Parts.Any()) return setters;

            var alwaysGenerate = new[] { "index" };
            var parts = Parts
                .Where(p => !p.Required || alwaysGenerate.Contains(p.Name))
                .Where(p => !string.IsNullOrEmpty(p.Name))
                .ToList();
            var returnType = CsharpNames.GenericOrNonGenericDescriptorName;
            foreach (var part in parts)
            {
                var p = part;
                var paramName = p.Name.ToPascalCase();
                if (paramName.Length > 1)
                    paramName = paramName.Substring(0, 1).ToLowerInvariant() + paramName.Substring(1);
                else
                    paramName = paramName.ToLowerInvariant();

                var routeValue = "v";
                var routeSetter = p.Required ? "Required" : "Optional";

                var code =
                    $"public {returnType} {p.InterfaceName}({p.HighLevelTypeName} {paramName}) => Assign({paramName}, (a,v)=>a.RouteValues.{routeSetter}(\"{p.Name}\", {routeValue}));";
                var xmlDoc = $"///<summary>{p.Description}</summary>";
                setters.Add(new FluentRouteSetter { Code = code, XmlDoc = xmlDoc });
                if (paramName == "index")
                {
                    code = $"public {returnType} {p.InterfaceName}<TOther>() where TOther : class ";
                    code += $"=> Assign(typeof(TOther), (a,v)=>a.RouteValues.{routeSetter}(\"{p.Name}\", ({p.HighLevelTypeName})v));";
                    xmlDoc = $"///<summary>a shortcut into calling {p.InterfaceName}(typeof(TOther))</summary>";
                    setters.Add(new FluentRouteSetter { Code = code, XmlDoc = xmlDoc });
                }
                if (paramName == "index" && p.Type == "list")
                {
                    code = $"public {returnType} AllIndices() => Index(Indices.All);";
                    xmlDoc = $"///<summary>A shortcut into calling Index(Indices.All)</summary>";
                    setters.Add(new FluentRouteSetter { Code = code, XmlDoc = xmlDoc });
                }
                if (paramName == "fields" && p.Type == "list")
                {
                    code = $"public {returnType} Fields<T>(params Expression<Func<T, object>>[] fields) ";
                    code += $"=> Assign(fields, (a,v)=>a.RouteValues.{routeSetter}(\"fields\", (Fields)v));";
                    xmlDoc = $"///<summary>{p.Description}</summary>";
                    setters.Add(new FluentRouteSetter { Code = code, XmlDoc = xmlDoc });
                }
            }
            return setters;
        }
    }
}