package schema

import (
	"encoding/json"
	"testing"
)

type SimpleParams struct {
	Name string `json:"name" description:"The name"`
	Age  int    `json:"age" description:"The age"`
}

type OptionalParams struct {
	Required string  `json:"required" description:"A required field"`
	Optional *string `json:"optional,omitempty" description:"An optional field"`
}

type EnumParams struct {
	Color string `json:"color" description:"The color" enum:"red,green,blue"`
}

type NestedParams struct {
	Inner SimpleParams `json:"inner" description:"Nested object"`
}

type ArrayParams struct {
	Items []string `json:"items" description:"A list of items"`
}

type EmbeddedBase struct {
	ID string `json:"id" description:"The ID"`
}

type EmbeddedParams struct {
	EmbeddedBase
	Name string `json:"name" description:"The name"`
}

func TestFromStruct_Simple(t *testing.T) {
	s := FromStruct(SimpleParams{})

	if s["type"] != "object" {
		t.Errorf("expected type=object, got %v", s["type"])
	}

	props, ok := s["properties"].(map[string]any)
	if !ok {
		t.Fatal("expected properties to be map[string]any")
	}

	if len(props) != 2 {
		t.Errorf("expected 2 properties, got %d", len(props))
	}

	nameSchema, ok := props["name"].(map[string]any)
	if !ok {
		t.Fatal("expected name property to be map[string]any")
	}
	if nameSchema["type"] != "string" {
		t.Errorf("expected name type=string, got %v", nameSchema["type"])
	}
	if nameSchema["description"] != "The name" {
		t.Errorf("expected name description='The name', got %v", nameSchema["description"])
	}

	ageSchema, ok := props["age"].(map[string]any)
	if !ok {
		t.Fatal("expected age property to be map[string]any")
	}
	if ageSchema["type"] != "integer" {
		t.Errorf("expected age type=integer, got %v", ageSchema["type"])
	}

	required, ok := s["required"].([]string)
	if !ok {
		t.Fatal("expected required to be []string")
	}
	if len(required) != 2 {
		t.Errorf("expected 2 required fields, got %d", len(required))
	}
}

func TestFromStruct_Optional(t *testing.T) {
	s := FromStruct(OptionalParams{})

	required, ok := s["required"].([]string)
	if !ok {
		t.Fatal("expected required to be []string")
	}

	// Only "required" field should be required, not "optional"
	if len(required) != 1 {
		t.Errorf("expected 1 required field, got %d: %v", len(required), required)
	}
	if required[0] != "required" {
		t.Errorf("expected required field 'required', got %v", required[0])
	}
}

func TestFromStruct_Enum(t *testing.T) {
	s := FromStruct(EnumParams{})

	props := s["properties"].(map[string]any)
	colorSchema := props["color"].(map[string]any)

	if colorSchema["type"] != "string" {
		t.Errorf("expected enum type=string, got %v", colorSchema["type"])
	}

	enums, ok := colorSchema["enum"].([]string)
	if !ok {
		t.Fatal("expected enum to be []string")
	}
	if len(enums) != 3 {
		t.Errorf("expected 3 enum values, got %d", len(enums))
	}
}

func TestFromStruct_Nested(t *testing.T) {
	s := FromStruct(NestedParams{})

	props := s["properties"].(map[string]any)
	innerSchema := props["inner"].(map[string]any)

	if innerSchema["type"] != "object" {
		t.Errorf("expected nested type=object, got %v", innerSchema["type"])
	}

	innerProps := innerSchema["properties"].(map[string]any)
	if len(innerProps) != 2 {
		t.Errorf("expected 2 inner properties, got %d", len(innerProps))
	}
}

func TestFromStruct_Array(t *testing.T) {
	s := FromStruct(ArrayParams{})

	props := s["properties"].(map[string]any)
	itemsSchema := props["items"].(map[string]any)

	if itemsSchema["type"] != "array" {
		t.Errorf("expected array type=array, got %v", itemsSchema["type"])
	}

	items := itemsSchema["items"].(map[string]any)
	if items["type"] != "string" {
		t.Errorf("expected items type=string, got %v", items["type"])
	}
}

func TestFromStruct_Embedded(t *testing.T) {
	s := FromStruct(EmbeddedParams{})

	props := s["properties"].(map[string]any)

	// Should have both ID from embedded and Name
	if len(props) != 2 {
		t.Errorf("expected 2 properties (flattened), got %d", len(props))
	}

	if _, ok := props["id"]; !ok {
		t.Error("expected 'id' property from embedded struct")
	}
	if _, ok := props["name"]; !ok {
		t.Error("expected 'name' property")
	}
}

func TestFromStruct_ValidJSON(t *testing.T) {
	s := FromStruct(SimpleParams{})

	data, err := json.Marshal(s)
	if err != nil {
		t.Fatalf("schema should be valid JSON: %v", err)
	}

	var parsed map[string]any
	if err := json.Unmarshal(data, &parsed); err != nil {
		t.Fatalf("schema should round-trip through JSON: %v", err)
	}
}