using System.Collections.Generic;
using System.Linq;

namespace SessionZero.Data;

[SzfObject("character_template")]
public class CharacterTemplate : SzfObject
{
    public string GameSystem { get; set; } = string.Empty;
    public List<RequiredDatasetReference> RequiredDatasets { get; set; } = new();
    public List<TemplateSection> Sections { get; set; } = new();
    
    public override void PopulateFromMetadata(Dictionary<string, SzfField> metadata)
    {
        base.PopulateFromMetadata(metadata);

        if (metadata.TryGetValue("GameSystem", out var gameSystemField))
            GameSystem = gameSystemField.Value?.ToString() ?? string.Empty;
    }

    public override void ParseSections(List<SzfSection> sections)
    {
        // Parse [Required Datasets] section
        var requiredDatasetsSection =
            sections.FirstOrDefault(s => s.Name.Equals("Required Datasets", StringComparison.OrdinalIgnoreCase));
        if (requiredDatasetsSection != null)
        {
            foreach (var field in requiredDatasetsSection.Fields)
            {
                var reference = DatasetReference.Parse(field.Value?.ToString() ?? string.Empty);
                if (reference != null)
                {
                    RequiredDatasets.Add(new RequiredDatasetReference
                    {
                        Alias = field.Name,
                        Reference = reference
                    });
                }
            }
        }

        // Parse [Section: ...] and [Section....] sections
        foreach (var szfSection in sections)
        {
            if (szfSection.Name.StartsWith("Section:", StringComparison.OrdinalIgnoreCase))
            {
                var templateSection = new TemplateSection
                {
                    Name = szfSection.Name.Replace("Section:", "").Trim()
                };

                foreach (var field in szfSection.Fields)
                {
                    templateSection.Fields.Add(ConvertToTemplateField(field));
                }

                Sections.Add(templateSection);
            }
            else if (szfSection.Name.StartsWith("Section.", StringComparison.OrdinalIgnoreCase))
            {
                // Handle subsections by finding their parent
                var parts = szfSection.Name.Split('.');
                if (parts.Length >= 2)
                {
                    var parentSectionName = parts[0] + ":" + parts[1].Trim(); // Reconstruct parent name
                    var parentSection = Sections.FirstOrDefault(s =>
                        s.Name.Equals(parentSectionName.Replace("Section:", "").Trim(),
                            StringComparison.OrdinalIgnoreCase));
                    if (parentSection != null)
                    {
                        var subSection = new TemplateSection
                        {
                            Name = string.Join(".", parts.Skip(2)).Trim() // Name for the subsection
                        };

                        foreach (var field in szfSection.Fields)
                        {
                            subSection.Fields.Add(ConvertToTemplateField(field));
                        }

                        parentSection.Subsections.Add(subSection);
                    }
                }
            }
        }
    }

    private TemplateField ConvertToTemplateField(SzfField szfField)
    {
        return new TemplateField
        {
            Name = szfField.Name,
            Type = ParseDatasetFieldType(szfField.Type),
            Value = szfField.Value
        };
    }

    private DatasetFieldType ParseDatasetFieldType(string typeString)
    {
        return typeString.ToLower() switch
        {
            "text" => DatasetFieldType.Text,
            "text-field" => DatasetFieldType.TextField,
            "number" => DatasetFieldType.Number,
            "bool" => DatasetFieldType.Boolean,
            "calculated" => DatasetFieldType.Calculated,
            "system" => DatasetFieldType.System,
            "dataset-reference" => DatasetFieldType.DatasetReference,
            "dataset-type" => DatasetFieldType.DatasetType,
            "dataset-reference-multiple" => DatasetFieldType.DatasetReferenceMultiple,
            "dataset-type-multiple" => DatasetFieldType.DatasetTypeMultiple,
            "group" => DatasetFieldType.Group,
            _ => DatasetFieldType.Text // Default to text if unknown
        };
    }

    public override void GenerateMetadata(SzfFieldWriter writer)
    {
        // Call base to ensure common metadata is generated first if base had any specific generation logic
        base.GenerateMetadata(writer);

        writer.WriteField("GameSystem", "text", GameSystem);
    }

    public override void GenerateContent(SzfFieldWriter writer)
    {
        // Generate [Required Datasets] section
        if (RequiredDatasets.Any() || writer.Options.IncludeEmptySections)
        {
            writer.AppendSectionHeader("Required Datasets");
            foreach (var reqDataset in RequiredDatasets)
            {
                writer.WriteField(reqDataset.Alias, "dataset-reference", reqDataset.Reference?.ToString());
            }

            writer.AppendLine();
        }

        // Generate Template Sections
        foreach (var section in Sections)
        {
            GenerateTemplateSection(writer, section, "Section");
            writer.AppendLine();
        }
    }

    private void GenerateTemplateSection(SzfFieldWriter writer, TemplateSection section, string parentPath)
    {
        var currentPath = $"{parentPath}: {section.Name}";
        writer.AppendSectionHeader(currentPath);

        foreach (var field in section.Fields)
        {
            writer.WriteField(field.Name, field.Type, field.Value);
        }

        foreach (var subSection in section.Subsections)
        {
            GenerateTemplateSubSection(writer, subSection, $"Section.{section.Name}");
        }
    }

    private void GenerateTemplateSubSection(SzfFieldWriter writer, TemplateSection subSection, string parentPath)
    {
        var currentPath = $"{parentPath}.{subSection.Name}";
        writer.AppendSectionHeader(currentPath);

        foreach (var field in subSection.Fields)
        {
            writer.WriteField(field.Name, field.Type, field.Value);
        }

        foreach (var nestedSubSection in subSection.Subsections)
        {
            // Handle deeper nesting if needed, recursively calling this method
            GenerateTemplateSubSection(writer, nestedSubSection, currentPath);
        }
    }

    public override SzfValidationResult Validate()
    {
        var result = base.Validate(); // Run base validation first

        if (string.IsNullOrWhiteSpace(GameSystem))
            result.AddError("GameSystem is required for CharacterTemplate");

        return result;
    }
}

public class RequiredDatasetReference
{
    public string Alias { get; set; } = string.Empty;
    public DatasetReference? Reference { get; set; }
}

public class TemplateSection
{
    public string Name { get; set; } = string.Empty;
    public List<TemplateField> Fields { get; set; } = new();
    public List<TemplateSection> Subsections { get; set; } = new(); // For nested sections
}

public class TemplateField
{
    public string Name { get; set; } = string.Empty;
    public DatasetFieldType Type { get; set; }
    public object? Value { get; set; }
}