using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using AI.Interface;
using AI.Models;
using AI.Models.Form;
using AI.Models.SpecialMessages;
using YamlDotNet.Core;
using YamlDotNet.Serialization;
using YamlDotNet.Serialization.NamingConventions;

namespace AI.Utils
{
    public static class SpecialMessageTypes
    {
        public const string Form = "Form";
        public const string ParameterSet = "ParameterSet";
        public const string Table = "Table";
        public const string ColumnMatch = "ColumnMatch";
        public const string WorkflowStatus = "WorkflowStatus";
        public const string KnowledgeBase = "KnowledgeBase";
        public const string XyzLoadCard = "XyzLoadCard";
        public const string GriddingParamCard = "GriddingParamCard";
    }

    /// <summary>
    /// 根据 type + YAML 载荷还原 ISpecialMessage。Form 需 IFormRegistry 根据 formId 取 FormDefinition。
    /// formId 缺失或 Definition 不存在时降级为占位或只读文本。
    /// </summary>
    public static class SpecialMessageDeserializer
    {
        public static ISpecialMessage? Deserialize(string type, string yamlPayload, IFormRegistry? formRegistry = null)
        {
            if (string.IsNullOrWhiteSpace(type) || string.IsNullOrWhiteSpace(yamlPayload))
            {
                return null;
            }

            try
            {
                return type.Trim() switch
                {
                    SpecialMessageTypes.Form => DeserializeForm(yamlPayload, formRegistry),
                    SpecialMessageTypes.ParameterSet => DeserializeParameterSet(yamlPayload),
                    SpecialMessageTypes.Table => DeserializeTable(yamlPayload),
                    SpecialMessageTypes.ColumnMatch => DeserializeColumnMatch(yamlPayload),
                    SpecialMessageTypes.WorkflowStatus => DeserializeWorkflowStatus(yamlPayload),
                    SpecialMessageTypes.KnowledgeBase => DeserializeKnowledgeBase(yamlPayload),
                    SpecialMessageTypes.XyzLoadCard => DeserializeXyzLoadCard(yamlPayload),
                    SpecialMessageTypes.GriddingParamCard => DeserializeGriddingParamCard(yamlPayload),
                    _ => null
                };
            }
            catch (Exception ex)
            {
                System.Diagnostics.Debug.WriteLine($"[SpecialMessageDeserializer] 反序列化失败: type={type}, error={ex}");
                return null;
            }
        }

        private static readonly IReadOnlyDictionary<string, (string TypeName, string[] DetailKeys)> ShortDescriptionTable =
            new Dictionary<string, (string, string[])>(StringComparer.OrdinalIgnoreCase)
            {
                [SpecialMessageTypes.Form] = ("表单", new[] { "title", "formId" }),
                [SpecialMessageTypes.ParameterSet] = ("参数集", new[] { "title" }),
                [SpecialMessageTypes.Table] = ("表格", new[] { "title" }),
                [SpecialMessageTypes.ColumnMatch] = ("列匹配", new[] { "title" }),
                [SpecialMessageTypes.WorkflowStatus] = ("工作流状态", new[] { "title" }),
                [SpecialMessageTypes.XyzLoadCard] = ("散点文件加载卡片", new[] { "filePath" }),
                [SpecialMessageTypes.GriddingParamCard] = ("网格化参数卡片", Array.Empty<string>()),
            };

        /// <summary>
        /// 从特殊消息的 type + YAML 载荷生成发给 LLM 的短描述（如「[已展示：表单「加载散点」]」），便于模型理解上下文。
        /// 对于 KnowledgeBase 类型，返回完整 rawContent，以便后续轮次 LLM 能看到查到的知识。
        /// </summary>
        public static string GetShortDescriptionForLlm(string type, string payload)
        {
            if (string.IsNullOrWhiteSpace(type))
            {
                return "[已展示：未知]";
            }
            if (string.IsNullOrWhiteSpace(payload))
            {
                return $"[已展示：{type}]";
            }

            try
            {
                var dict = FromYaml(payload);
                if (dict == null)
                {
                    return $"[已展示：{type}]";
                }

                // 知识库条目：把完整内容带给 LLM，作为后续对话的参考
                if (string.Equals(type.Trim(), SpecialMessageTypes.KnowledgeBase, StringComparison.OrdinalIgnoreCase))
                {
                    var rawContent = GetString(dict, "rawContent");
                    return string.IsNullOrWhiteSpace(rawContent)
                        ? "[已查询知识库，无匹配内容]"
                        : $"[来自知识库的参考]{System.Environment.NewLine}{rawContent}";
                }

                string typeName = type;
                string? detail = null;

                if (ShortDescriptionTable.TryGetValue(type.Trim(), out var row))
                {
                    typeName = row.TypeName;
                    foreach (var key in row.DetailKeys)
                    {
                        var value = GetString(dict, key);
                        if (!string.IsNullOrWhiteSpace(value))
                        {
                            detail = value;
                            break;
                        }
                    }
                }

                if (!string.IsNullOrWhiteSpace(detail))
                {
                    return $"[已展示：{typeName}「{detail}」]";
                }

                return $"[已展示：{typeName}]";
            }
            catch
            {
                return $"[已展示：{type}]";
            }
        }

        private static ISpecialMessage? DeserializeForm(string yaml, IFormRegistry? formRegistry)
        {
            var dict = FromYaml(yaml);
            if (dict == null)
            {
                return null;
            }

            string formId = GetString(dict, "formId") ?? string.Empty;
            FormDefinition? definition = null;
            if (formRegistry != null && !string.IsNullOrEmpty(formId))
            {
                definition = formRegistry.GetForm(formId);
            }

            if (definition == null)
            {
                return null; // 降级：无 FormRegistry 或 formId 不存在时不还原表单卡片
            }

            var formMsg = new FormRequestMessage(definition);
            if (TryGet(dict, "id", out var idObj))
            {
                formMsg.Id = idObj?.ToString() ?? formMsg.Id;
            }

            if (TryGet(dict, "submitLabel", out var submitObj))
            {
                formMsg.SubmitLabel = submitObj?.ToString() ?? formMsg.SubmitLabel;
            }

            if (TryGet(dict, "fields", out var fieldsObj) && fieldsObj is IEnumerable<object> fieldsList)
            {
                foreach (var fe in fieldsList)
                {
                    if (fe is not Dictionary<object, object> fieldDict)
                    {
                        continue;
                    }

                    string fid = GetString(fieldDict, "id") ?? string.Empty;
                    var entry = formMsg.FieldsWithValues.FirstOrDefault(f => string.Equals(f.Id, fid, StringComparison.OrdinalIgnoreCase));
                    if (entry == null)
                    {
                        continue;
                    }
                    entry.CurrentValue = GetString(fieldDict, "currentValue") ?? string.Empty;
                    if (TryGet(fieldDict, "selectedValues", out var svObj) && svObj is IEnumerable<object> svList)
                    {
                        entry.SelectedValues.Clear();
                        foreach (var v in svList)
                        {
                            if (v?.ToString() is string s)
                            {
                                entry.SelectedValues.Add(s);
                            }
                        }
                    }
                }
            }

            return formMsg;
        }

        private static ISpecialMessage? DeserializeParameterSet(string yaml)
        {
            var dict = FromYaml(yaml);
            if (dict == null)
            {
                return null;
            }

            var param = new ParameterSetMessage();
            if (TryGet(dict, "id", out var idObj))
            {
                param.Id = idObj?.ToString() ?? param.Id;
            }

            param.Title = GetString(dict, "title") ?? param.Title;

            if (TryGet(dict, "items", out var itemsObj) && itemsObj is IEnumerable<object> itemsList)
            {
                foreach (var item in itemsList)
                {
                    if (item is not Dictionary<object, object> id)
                    {
                        continue;
                    }
                    var name = GetString(id, "name") ?? string.Empty;
                    var valueText = GetString(id, "valueText") ?? string.Empty;
                    var description = GetString(id, "description") ?? string.Empty;
                    var fieldTypeStr = GetString(id, "fieldType");
                    var fieldType = ParameterSetFieldType.Text;
                    if (!string.IsNullOrEmpty(fieldTypeStr) && Enum.TryParse<ParameterSetFieldType>(fieldTypeStr, true, out var ft))
                    {
                        fieldType = ft;
                    }
                    var options = new List<string>();
                    if (TryGet(id, "options", out var optObj) && optObj is IEnumerable<object> optList)
                    {
                        foreach (var o in optList)
                        {
                            if (o?.ToString() is string s)
                            {
                                options.Add(s);
                            }
                        }
                    }
                    param.Items.Add(new ParameterSetItem
                    {
                        Name = name,
                        ValueText = valueText,
                        Description = description,
                        FieldType = fieldType,
                        Options = options
                    });
                }
            }
            return param;
        }

        private static ISpecialMessage? DeserializeTable(string yaml)
        {
            var dict = FromYaml(yaml);
            if (dict == null)
            {
                return null;
            }

            var table = new TableDataMessage();
            if (TryGet(dict, "id", out var idObj))
            {
                table.Id = idObj?.ToString() ?? table.Id;
            }

            table.Title = GetString(dict, "title") ?? table.Title;
            table.TotalRowCount = GetInt(dict, "totalRowCount") ?? 0;
            table.MaxPreviewRows = GetInt(dict, "maxPreviewRows") ?? 50;

            var columnNames = new List<string>();
            if (TryGet(dict, "columnNames", out var cnObj) && cnObj is IEnumerable<object> cnList)
            {
                foreach (var c in cnList)
                {
                    if (c?.ToString() is string s)
                    {
                        columnNames.Add(s);
                    }
                }
            }

            var rows = new List<IEnumerable<string>>();
            if (TryGet(dict, "rows", out var rowsObj) && rowsObj is IEnumerable<object> rowsList)
            {
                foreach (var rowObj in rowsList)
                {
                    if (rowObj is IEnumerable<object> cells)
                    {
                        rows.Add(cells.Select(c => c?.ToString() ?? string.Empty).ToList());
                    }
                }
            }

            table.SetData(columnNames, rows, table.TotalRowCount > 0 ? table.TotalRowCount : rows.Count);
            return table;
        }

        private static ISpecialMessage? DeserializeColumnMatch(string yaml)
        {
            var dict = FromYaml(yaml);
            if (dict == null)
            {
                return null;
            }

            var col = new ColumnMatchMessage();
            if (TryGet(dict, "id", out var idObj))
            {
                col.Id = idObj?.ToString() ?? col.Id;
            }

            col.Title = GetString(dict, "title") ?? col.Title;

            var required = new List<string>();
            if (TryGet(dict, "requiredColumns", out var rcObj) && rcObj is IEnumerable<object> rcList)
            {
                foreach (var c in rcList)
                {
                    if (c?.ToString() is string s)
                    {
                        required.Add(s);
                    }
                }
            }
            var preview = new List<string>();
            if (TryGet(dict, "previewColumns", out var pcObj) && pcObj is IEnumerable<object> pcList)
            {
                foreach (var c in pcList)
                {
                    if (c?.ToString() is string s)
                    {
                        preview.Add(s);
                    }
                }
            }
            col.SetColumns(required, preview);

            if (TryGet(dict, "mappings", out var mapObj) && mapObj is IEnumerable<object> mapList)
            {
                var mappings = new List<KeyValuePair<string, string>>();
                foreach (var m in mapList)
                {
                    if (m is not Dictionary<object, object> md)
                    {
                        continue;
                    }
                    string req = GetString(md, "requiredColumn") ?? string.Empty;
                    string mat = GetString(md, "matchedColumn") ?? string.Empty;
                    mappings.Add(new KeyValuePair<string, string>(req, mat));
                }
                col.SetMappings(mappings);
            }
            return col;
        }

        private static ISpecialMessage? DeserializeKnowledgeBase(string yaml)
        {
            var dict = FromYaml(yaml);
            if (dict == null)
            {
                return null;
            }

            var kb = new KnowledgeBaseMessage();
            if (TryGet(dict, "id", out var idObj))
            {
                kb.Id = idObj?.ToString() ?? kb.Id;
            }

            kb.KnowledgeId = GetString(dict, "knowledgeId") ?? string.Empty;
            kb.Version = GetString(dict, "version") ?? "1";
            kb.TopicKey = GetString(dict, "topicKey") ?? string.Empty;
            kb.Query = GetString(dict, "query") ?? string.Empty;
            kb.RawContent = GetString(dict, "rawContent") ?? string.Empty;
            return kb;
        }

        private static ISpecialMessage? DeserializeWorkflowStatus(string yaml)
        {
            var dict = FromYaml(yaml);
            if (dict == null)
            {
                return null;
            }

            var wf = new WorkflowStatusMessage();
            if (TryGet(dict, "id", out var idObj))
            {
                wf.Id = idObj?.ToString() ?? wf.Id;
            }

            wf.Title = GetString(dict, "title") ?? wf.Title;

            if (TryGet(dict, "steps", out var stepsObj) && stepsObj is IEnumerable<object> stepsList)
            {
                var steps = new ObservableCollection<WorkflowStepModel>();
                foreach (var s in stepsList)
                {
                    if (s is not Dictionary<object, object> sd)
                    {
                        continue;
                    }
                    var step = new WorkflowStepModel
                    {
                        Id = GetString(sd, "id") ?? string.Empty,
                        DisplayName = GetString(sd, "displayName") ?? string.Empty,
                        Order = GetInt(sd, "order") ?? 0,
                        OutputResult = GetString(sd, "outputResult"),
                        Thought = GetString(sd, "thought")
                    };
                    var statusStr = GetString(sd, "status");
                    if (!string.IsNullOrEmpty(statusStr) && Enum.TryParse<WorkflowStepStatus>(statusStr, true, out var st))
                    {
                        step.Status = st;
                    }
                    steps.Add(step);
                }
                wf.Steps = steps;
            }
            return wf;
        }

        private static ISpecialMessage? DeserializeXyzLoadCard(string yaml)
        {
            var dict = FromYaml(yaml);
            if (dict == null) return null;

            var card = new AI.Models.SpecialMessages.XyzLoadCardMessage();

            if (TryGet(dict, "id", out var idObj))
                card.Id = idObj?.ToString() ?? card.Id;

            card.FilePath = GetString(dict, "filePath") ?? string.Empty;
            card.MatchButtonLabel = GetString(dict, "matchButtonLabel") ?? "确认匹配";

            var phaseInt = GetInt(dict, "phase") ?? 0;
            card.Phase = (AI.Models.SpecialMessages.XyzLoadPhase)phaseInt;

            // 还原表格预览
            if (TryGet(dict, "tablePreview", out var tableObj) && tableObj is Dictionary<object, object> tableDict)
            {
                var table = new AI.Models.SpecialMessages.TableDataMessage();
                table.Title = GetString(tableDict, "title") ?? "数据预览";
                table.TotalRowCount = GetInt(tableDict, "totalRowCount") ?? 0;
                table.MaxPreviewRows = GetInt(tableDict, "maxPreviewRows") ?? 50;

                var colNames = new List<string>();
                if (TryGet(tableDict, "columnNames", out var cnObj) && cnObj is IEnumerable<object> cnList)
                    foreach (var c in cnList)
                        if (c?.ToString() is string s) colNames.Add(s);

                var rows = new List<IEnumerable<string>>();
                if (TryGet(tableDict, "rows", out var rowsObj) && rowsObj is IEnumerable<object> rowsList)
                    foreach (var rowObj in rowsList)
                        if (rowObj is IEnumerable<object> cells)
                            rows.Add(cells.Select(c => c?.ToString() ?? string.Empty).ToList());

                table.SetData(colNames, rows, table.TotalRowCount > 0 ? table.TotalRowCount : rows.Count);
                card.TablePreview = table;
            }

            // 还原列头匹配字段
            if (TryGet(dict, "columnMatchFields", out var fieldsObj) && fieldsObj is IEnumerable<object> fieldsList)
            {
                var definitionTitle = GetString(dict, "columnMatchDefinitionTitle") ?? "列头匹配";
                var definitionTarget = GetString(dict, "columnMatchDefinitionSubmitTarget") ?? "GriddingModuleMatchColumns";

                var formFields = new List<AI.Models.Form.FormField>();
                foreach (var fe in fieldsList)
                {
                    if (fe is not Dictionary<object, object> fd) continue;
                    var fid = GetString(fd, "id") ?? string.Empty;
                    var label = GetString(fd, "label") ?? fid;
                    var currentValue = GetString(fd, "currentValue") ?? string.Empty;
                    var options = new List<string>();
                    if (TryGet(fd, "options", out var optObj) && optObj is IEnumerable<object> optList)
                        foreach (var o in optList)
                            if (o?.ToString() is string s) options.Add(s);

                    formFields.Add(new AI.Models.Form.FormField
                    {
                        Id = fid,
                        Label = label,
                        Type = AI.Models.Form.FormFieldType.Choice,
                        Options = options,
                        Required = true,
                    });

                    card.ColumnMatchFields.Add(new AI.Models.Form.FormFieldEntry
                    {
                        Id = fid,
                        Label = label,
                        Type = AI.Models.Form.FormFieldType.Choice,
                        Options = options,
                        Required = true,
                        CurrentValue = currentValue,
                    });
                }

                if (formFields.Count > 0)
                {
                    card.ColumnMatchDefinition = new AI.Models.Form.FormDefinition
                    {
                        Id = "gridding-match-columns",
                        Title = definitionTitle,
                        SubmitTarget = definitionTarget,
                        SubmitLabel = "确认匹配",
                        Fields = formFields,
                    };
                }
            }

            return card;
        }

        private static ISpecialMessage? DeserializeGriddingParamCard(string yaml)
        {
            var dict = FromYaml(yaml);
            if (dict == null) return null;

            var card = new AI.Models.SpecialMessages.GriddingParamCardMessage();

            if (TryGet(dict, "id", out var idObj))
                card.Id = idObj?.ToString() ?? card.Id;

            var phaseInt = GetInt(dict, "phase") ?? 0;
            card.Phase = (AI.Models.SpecialMessages.GriddingParamCardPhase)phaseInt;
            card.StatusMessage = GetString(dict, "statusMessage") ?? string.Empty;
            card.GenerateButtonLabel = GetString(dict, "generateButtonLabel") ?? "生成";

            if (TryGet(dict, "items", out var itemsObj) && itemsObj is IEnumerable<object> itemsList)
            {
                foreach (var item in itemsList)
                {
                    if (item is not Dictionary<object, object> id) continue;
                    var name = GetString(id, "name") ?? string.Empty;
                    var valueText = GetString(id, "valueText") ?? string.Empty;
                    var description = GetString(id, "description") ?? string.Empty;
                    var fieldTypeStr = GetString(id, "fieldType");
                    var fieldType = AI.Models.SpecialMessages.ParameterSetFieldType.Text;
                    if (!string.IsNullOrEmpty(fieldTypeStr) &&
                        Enum.TryParse<AI.Models.SpecialMessages.ParameterSetFieldType>(fieldTypeStr, true, out var ft))
                        fieldType = ft;

                    var options = new List<string>();
                    if (TryGet(id, "options", out var optObj) && optObj is IEnumerable<object> optList)
                        foreach (var o in optList)
                            if (o?.ToString() is string s) options.Add(s);

                    card.Items.Add(new AI.Models.SpecialMessages.ParameterSetItem
                    {
                        Name = name,
                        ValueText = valueText,
                        Description = description,
                        FieldType = fieldType,
                        Options = options
                    });
                }
            }

            return card;
        }

        private static readonly IDeserializer YamlDeserializer = new DeserializerBuilder()
            .WithNamingConvention(CamelCaseNamingConvention.Instance)
            .IgnoreUnmatchedProperties()
            .Build();

        private static Dictionary<object, object>? FromYaml(string yaml)
        {
            try
            {
                return YamlDeserializer.Deserialize<Dictionary<object, object>>(yaml);
            }
            catch (YamlException ex)
            {
                System.Diagnostics.Debug.WriteLine($"[SpecialMessageDeserializer] YAML 解析失败: {ex.Message}");
                return null;
            }
        }

        private static string? GetString(Dictionary<object, object> dict, string key)
        {
            if (!TryGet(dict, key, out var v))
            {
                return null;
            }
            return v?.ToString();
        }

        private static int? GetInt(Dictionary<object, object> dict, string key)
        {
            if (!TryGet(dict, key, out var v))
            {
                return null;
            }

            if (v is int i)
            {
                return i;
            }

            if (v is long l)
            {
                return (int)l;
            }

            if (v != null && int.TryParse(v.ToString(), out var n))
            {
                return n;
            }

            return null;
        }

        private static bool TryGet(Dictionary<object, object> dict, string key, out object? value)
        {
            value = null;
            var keyEq = StringComparer.OrdinalIgnoreCase;
            foreach (var kv in dict)
            {
                if (keyEq.Equals(kv.Key?.ToString(), key))
                {
                    value = kv.Value;
                    return true;
                }
            }
            return false;
        }
    }
}