using System;
using System.Collections.Generic;
using System.Xml.Serialization;

namespace XSDVisualiser.Models
{
    /// <summary>
    /// Root of the parsed XSD representation.
    /// </summary>
    [XmlRoot("SchemaModel")]
    public class SchemaModel
    {
        [XmlAttribute]
        public string? TargetNamespace { get; set; }

        [XmlArray("RootElements")]
        [XmlArrayItem("Element")]
        public List<SchemaNode> RootElements { get; set; } = new();
    }

    /// <summary>
    /// Represents an element or complex content node in the schema.
    /// </summary>
    public class SchemaNode
    {
        [XmlAttribute]
        public string? Name { get; set; }

        [XmlAttribute]
        public string? Namespace { get; set; }

        [XmlAttribute]
        public string? TypeName { get; set; }

        [XmlAttribute]
        public string? BuiltInType { get; set; }

        [XmlAttribute]
        public bool IsNillable { get; set; }

        [XmlElement]
        public Occurs Cardinality { get; set; } = new();

        [XmlElement]
        public ConstraintSet? Constraints { get; set; }

        [XmlArray("Attributes")]
        [XmlArrayItem("Attribute")]
        public List<AttributeInfo> Attributes { get; set; } = new();

        [XmlArray("Children")]
        [XmlArrayItem("Element")]
        public List<SchemaNode> Children { get; set; } = new();

        [XmlAttribute]
        public string? ContentModel { get; set; } // sequence | choice | all | simple

        /// <summary>
        /// Human-readable documentation extracted from xsd:annotation/xsd:documentation.
        /// Prefer element-level documentation; falls back to type-level documentation.
        /// </summary>
        [XmlElement]
        public string? Documentation { get; set; }

        public override string ToString()
        {
            // Used by AutoCompleteBox to get text for filtering and matching
            // Prefer Name, then TypeName, and fall back to base implementation
            if (!string.IsNullOrEmpty(Name))
                return Name!;
            if (!string.IsNullOrEmpty(TypeName))
                return TypeName!;
            return base.ToString();
        }
    }

    /// <summary>
    /// Min/Max occurrences.
    /// </summary>
    public class Occurs
    {
        [XmlAttribute]
        public decimal Min { get; set; } = 1;

        /// <summary>
        /// If MaxIsUnbounded is true, Max is ignored.
        /// </summary>
        [XmlAttribute]
        public decimal Max { get; set; } = 1;

        [XmlAttribute]
        public bool MaxIsUnbounded { get; set; }
    }

    /// <summary>
    /// Attribute definition extracted from XSD.
    /// </summary>
    public class AttributeInfo
    {
        [XmlAttribute]
        public string? Name { get; set; }

        [XmlAttribute]
        public string? Namespace { get; set; }

        [XmlAttribute]
        public string? Use { get; set; } // optional | required | prohibited

        [XmlAttribute]
        public string? TypeName { get; set; }

        [XmlAttribute]
        public string? BuiltInType { get; set; }

        [XmlElement]
        public ConstraintSet? Constraints { get; set; }
    }

    /// <summary>
    /// SimpleType constraints (formerly called facets).
    /// </summary>
    public class ConstraintSet
    {
        [XmlAttribute]
        public string? BaseTypeName { get; set; }

        // Generic catch-all list of constraints for dynamic display and tooling
        [XmlArray("Constraints")]
        [XmlArrayItem("Constraint")]
        public List<ConstraintEntry> Constraints { get; set; } = new();
    }

    public class ConstraintEntry
    {
        [XmlAttribute]
        public string? Name { get; set; }
        [XmlAttribute]
        public string? Value { get; set; }
    }
}