package reflection

import (
	"reflect"
	"testing"
)

// Test models for GetModelColumnDetail
type TestModelForColumnDetail struct {
	ID          int    `gorm:"column:rid_test;primaryKey;type:bigserial;not null" json:"id"`
	Name        string `gorm:"column:name;type:varchar(255);not null" json:"name"`
	Email       string `gorm:"column:email;type:varchar(255);unique;nullable" json:"email"`
	Description string `gorm:"column:description;type:text;null" json:"description"`
	ForeignKey  int    `gorm:"foreignKey:parent_id" json:"foreign_key"`
}

type EmbeddedBase struct {
	ID        int    `gorm:"column:rid_base;primaryKey;identity" json:"id"`
	CreatedAt string `gorm:"column:created_at;type:timestamp" json:"created_at"`
}

type ModelWithEmbeddedForDetail struct {
	EmbeddedBase
	Title   string `gorm:"column:title;type:varchar(100);not null" json:"title"`
	Content string `gorm:"column:content;type:text" json:"content"`
}

// Model with nil embedded pointer
type ModelWithNilEmbedded struct {
	ID           int            `gorm:"column:id;primaryKey" json:"id"`
	*EmbeddedBase
	Name         string         `gorm:"column:name" json:"name"`
}

func TestGetModelColumnDetail(t *testing.T) {
	t.Run("simple struct", func(t *testing.T) {
		model := TestModelForColumnDetail{
			ID:          1,
			Name:        "Test",
			Email:       "test@example.com",
			Description: "Test description",
			ForeignKey:  100,
		}

		details := GetModelColumnDetail(reflect.ValueOf(model))

		if len(details) != 5 {
			t.Errorf("Expected 5 fields, got %d", len(details))
		}

		// Check ID field
		found := false
		for _, detail := range details {
			if detail.Name == "ID" {
				found = true
				if detail.SQLName != "rid_test" {
					t.Errorf("Expected SQLName 'rid_test', got '%s'", detail.SQLName)
				}
				// Note: primaryKey (without underscore) is not detected as primary_key
				// The function looks for "identity" or "primary_key" (with underscore)
				if detail.SQLDataType != "bigserial" {
					t.Errorf("Expected SQLDataType 'bigserial', got '%s'", detail.SQLDataType)
				}
				if detail.Nullable {
					t.Errorf("Expected Nullable false, got true")
				}
			}
		}
		if !found {
			t.Errorf("ID field not found in details")
		}
	})

	t.Run("struct with embedded fields", func(t *testing.T) {
		model := ModelWithEmbeddedForDetail{
			EmbeddedBase: EmbeddedBase{
				ID:        1,
				CreatedAt: "2024-01-01",
			},
			Title:   "Test Title",
			Content: "Test Content",
		}

		details := GetModelColumnDetail(reflect.ValueOf(model))

		// Should have 4 fields: ID, CreatedAt from embedded, Title, Content from main
		if len(details) != 4 {
			t.Errorf("Expected 4 fields, got %d", len(details))
		}

		// Check that embedded field is included
		foundID := false
		foundCreatedAt := false
		for _, detail := range details {
			if detail.Name == "ID" {
				foundID = true
				if detail.SQLKey != "primary_key" {
					t.Errorf("Expected SQLKey 'primary_key' for embedded ID, got '%s'", detail.SQLKey)
				}
			}
			if detail.Name == "CreatedAt" {
				foundCreatedAt = true
			}
		}
		if !foundID {
			t.Errorf("Embedded ID field not found")
		}
		if !foundCreatedAt {
			t.Errorf("Embedded CreatedAt field not found")
		}
	})

	t.Run("nil embedded pointer is skipped", func(t *testing.T) {
		model := ModelWithNilEmbedded{
			ID:   1,
			Name: "Test",
			EmbeddedBase: nil, // nil embedded pointer
		}

		details := GetModelColumnDetail(reflect.ValueOf(model))

		// Should have 2 fields: ID and Name (embedded is nil, so skipped)
		if len(details) != 2 {
			t.Errorf("Expected 2 fields (nil embedded skipped), got %d", len(details))
		}
	})

	t.Run("pointer to struct", func(t *testing.T) {
		model := &TestModelForColumnDetail{
			ID:   1,
			Name: "Test",
		}

		details := GetModelColumnDetail(reflect.ValueOf(model))

		if len(details) != 5 {
			t.Errorf("Expected 5 fields, got %d", len(details))
		}
	})

	t.Run("invalid value", func(t *testing.T) {
		var invalid reflect.Value
		details := GetModelColumnDetail(invalid)

		if len(details) != 0 {
			t.Errorf("Expected 0 fields for invalid value, got %d", len(details))
		}
	})

	t.Run("non-struct type", func(t *testing.T) {
		details := GetModelColumnDetail(reflect.ValueOf(123))

		if len(details) != 0 {
			t.Errorf("Expected 0 fields for non-struct, got %d", len(details))
		}
	})

	t.Run("nullable and not null detection", func(t *testing.T) {
		model := TestModelForColumnDetail{}
		details := GetModelColumnDetail(reflect.ValueOf(model))

		for _, detail := range details {
			switch detail.Name {
			case "ID":
				if detail.Nullable {
					t.Errorf("ID should not be nullable (has 'not null')")
				}
			case "Name":
				if detail.Nullable {
					t.Errorf("Name should not be nullable (has 'not null')")
				}
			case "Email":
				if !detail.Nullable {
					t.Errorf("Email should be nullable (has 'nullable')")
				}
			case "Description":
				if !detail.Nullable {
					t.Errorf("Description should be nullable (has 'null')")
				}
			}
		}
	})

	t.Run("unique and uniqueindex detection", func(t *testing.T) {
		type UniqueTestModel struct {
			ID       int    `gorm:"column:id;primary_key"`
			Username string `gorm:"column:username;unique"`
			Email    string `gorm:"column:email;uniqueindex"`
		}

		model := UniqueTestModel{}
		details := GetModelColumnDetail(reflect.ValueOf(model))

		for _, detail := range details {
			switch detail.Name {
			case "ID":
				if detail.SQLKey != "primary_key" {
					t.Errorf("ID should have SQLKey 'primary_key', got '%s'", detail.SQLKey)
				}
			case "Username":
				if detail.SQLKey != "unique" {
					t.Errorf("Username should have SQLKey 'unique', got '%s'", detail.SQLKey)
				}
			case "Email":
				// The function checks for "unique" first, so uniqueindex is also detected as "unique"
				// This is expected behavior based on the code logic
				if detail.SQLKey != "unique" {
					t.Errorf("Email should have SQLKey 'unique' (uniqueindex contains 'unique'), got '%s'", detail.SQLKey)
				}
			}
		}
	})

	t.Run("foreign key detection", func(t *testing.T) {
		// Note: The foreignkey extraction in generic_model.go has a bug where
		// it requires ik > 0, so foreignkey at the start won't extract the value
		type FKTestModel struct {
			ParentID int `gorm:"column:parent_id;foreignkey:rid_parent;association_foreignkey:id_atevent"`
		}

		model := FKTestModel{}
		details := GetModelColumnDetail(reflect.ValueOf(model))

		if len(details) == 0 {
			t.Fatal("Expected at least 1 field")
		}

		detail := details[0]
		if detail.SQLKey != "foreign_key" {
			t.Errorf("Expected SQLKey 'foreign_key', got '%s'", detail.SQLKey)
		}
		// Due to the bug in the code (requires ik > 0), the SQLName will be extracted
		// when foreignkey is not at the beginning of the string
		if detail.SQLName != "rid_parent" {
			t.Errorf("Expected SQLName 'rid_parent', got '%s'", detail.SQLName)
		}
	})
}

func TestFnFindKeyVal(t *testing.T) {
	tests := []struct {
		name     string
		src      string
		key      string
		expected string
	}{
		{
			name:     "find column",
			src:      "column:user_id;primaryKey;type:bigint",
			key:      "column:",
			expected: "user_id",
		},
		{
			name:     "find type",
			src:      "column:name;type:varchar(255);not null",
			key:      "type:",
			expected: "varchar(255)",
		},
		{
			name:     "key not found",
			src:      "primaryKey;autoIncrement",
			key:      "column:",
			expected: "",
		},
		{
			name:     "key at end without semicolon",
			src:      "primaryKey;column:id",
			key:      "column:",
			expected: "id",
		},
		{
			name:     "case insensitive search",
			src:      "Column:user_id;primaryKey",
			key:      "column:",
			expected: "user_id",
		},
		{
			name:     "empty src",
			src:      "",
			key:      "column:",
			expected: "",
		},
		{
			name:     "multiple occurrences (returns first)",
			src:      "column:first;column:second",
			key:      "column:",
			expected: "first",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			result := fnFindKeyVal(tt.src, tt.key)
			if result != tt.expected {
				t.Errorf("fnFindKeyVal(%q, %q) = %q, want %q", tt.src, tt.key, result, tt.expected)
			}
		})
	}
}

func TestGetModelColumnDetail_FieldValue(t *testing.T) {
	model := TestModelForColumnDetail{
		ID:    123,
		Name:  "TestName",
		Email: "test@example.com",
	}

	details := GetModelColumnDetail(reflect.ValueOf(model))

	for _, detail := range details {
		if !detail.FieldValue.IsValid() {
			t.Errorf("Field %s has invalid FieldValue", detail.Name)
		}

		// Check that FieldValue matches the actual value
		switch detail.Name {
		case "ID":
			if detail.FieldValue.Int() != 123 {
				t.Errorf("Expected ID FieldValue 123, got %v", detail.FieldValue.Int())
			}
		case "Name":
			if detail.FieldValue.String() != "TestName" {
				t.Errorf("Expected Name FieldValue 'TestName', got %v", detail.FieldValue.String())
			}
		case "Email":
			if detail.FieldValue.String() != "test@example.com" {
				t.Errorf("Expected Email FieldValue 'test@example.com', got %v", detail.FieldValue.String())
			}
		}
	}
}