package validation

import (
	"strings"
	"testing"

	"git.techease.ru/Smart-search/smart-search-back/pkg/errors"
	"github.com/stretchr/testify/assert"
)

func TestValidateEmail(t *testing.T) {
	tests := []struct {
		name     string
		email    string
		wantErr  bool
		wantCode string
	}{
		{"valid email", "test@example.com", false, ""},
		{"valid with subdomain", "test@sub.example.com", false, ""},
		{"valid with plus", "test+tag@example.com", false, ""},
		{"valid with dots", "test.name@example.com", false, ""},
		{"empty", "", true, errors.ValidationInvalidEmail},
		{"no at sign", "testexample.com", true, errors.ValidationInvalidEmail},
		{"no domain", "test@", true, errors.ValidationInvalidEmail},
		{"no local part", "@example.com", true, errors.ValidationInvalidEmail},
		{"double dots in domain", "test@example..com", true, errors.ValidationInvalidEmail},
		{"too long", strings.Repeat("a", 255) + "@example.com", true, errors.ValidationInvalidEmail},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateEmail(tt.email)
			if tt.wantErr {
				assert.Error(t, err)
				if appErr, ok := err.(*errors.AppError); ok {
					assert.Equal(t, tt.wantCode, appErr.Code)
				}
			} else {
				assert.NoError(t, err)
			}
		})
	}
}

func TestValidatePassword(t *testing.T) {
	tests := []struct {
		name     string
		password string
		wantErr  bool
		wantCode string
	}{
		{"valid password", "Abcd1234", false, ""},
		{"valid with special chars", "Abcd1234!", false, ""},
		{"empty", "", true, errors.ValidationInvalidPassword},
		{"too short", "Ab1", true, errors.ValidationInvalidPassword},
		{"no uppercase", "abcd1234", true, errors.ValidationInvalidPassword},
		{"no lowercase", "ABCD1234", true, errors.ValidationInvalidPassword},
		{"no digit", "Abcdefgh", true, errors.ValidationInvalidPassword},
		{"only digits", "12345678", true, errors.ValidationInvalidPassword},
		{"only lowercase", "abcdefgh", true, errors.ValidationInvalidPassword},
		{"only uppercase", "ABCDEFGH", true, errors.ValidationInvalidPassword},
		{"too long", strings.Repeat("Aa1", 50), true, errors.ValidationInvalidPassword},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidatePassword(tt.password)
			if tt.wantErr {
				assert.Error(t, err)
				if appErr, ok := err.(*errors.AppError); ok {
					assert.Equal(t, tt.wantCode, appErr.Code)
				}
			} else {
				assert.NoError(t, err)
			}
		})
	}
}

func TestValidatePhone(t *testing.T) {
	tests := []struct {
		name     string
		phone    string
		wantErr  bool
		wantCode string
	}{
		{"valid international", "+1234567890", false, ""},
		{"valid with country code", "+79123456789", false, ""},
		{"valid without plus", "1234567890", false, ""},
		{"empty", "", true, errors.ValidationInvalidPhone},
		{"too short", "123", true, errors.ValidationInvalidPhone},
		{"letters", "abcdefgh", true, errors.ValidationInvalidPhone},
		{"too long", "+123456789012345678901", true, errors.ValidationInvalidPhone},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidatePhone(tt.phone)
			if tt.wantErr {
				assert.Error(t, err)
				if appErr, ok := err.(*errors.AppError); ok {
					assert.Equal(t, tt.wantCode, appErr.Code)
				}
			} else {
				assert.NoError(t, err)
			}
		})
	}
}

func TestValidateName(t *testing.T) {
	tests := []struct {
		name     string
		value    string
		wantErr  bool
		wantCode string
	}{
		{"valid name", "John Doe", false, ""},
		{"valid cyrillic", "Иван Иванов", false, ""},
		{"empty", "", true, errors.ValidationInvalidName},
		{"only whitespace", "   ", true, errors.ValidationInvalidName},
		{"too long", strings.Repeat("a", 101), true, errors.ValidationInvalidName},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateName(tt.value)
			if tt.wantErr {
				assert.Error(t, err)
				if appErr, ok := err.(*errors.AppError); ok {
					assert.Equal(t, tt.wantCode, appErr.Code)
				}
			} else {
				assert.NoError(t, err)
			}
		})
	}
}

func TestValidateRequestTxt(t *testing.T) {
	tests := []struct {
		name     string
		txt      string
		wantErr  bool
		wantCode string
	}{
		{"valid short", "Test request", false, ""},
		{"empty is valid", "", false, ""},
		{"max length", strings.Repeat("a", MaxRequestTxtLen), false, ""},
		{"too long", strings.Repeat("a", MaxRequestTxtLen+1), true, errors.ValidationRequestTooLong},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateRequestTxt(tt.txt)
			if tt.wantErr {
				assert.Error(t, err)
				if appErr, ok := err.(*errors.AppError); ok {
					assert.Equal(t, tt.wantCode, appErr.Code)
				}
			} else {
				assert.NoError(t, err)
			}
		})
	}
}

func TestValidateFileSize(t *testing.T) {
	tests := []struct {
		name     string
		size     int
		wantErr  bool
		wantCode string
	}{
		{"zero", 0, false, ""},
		{"small file", 1024, false, ""},
		{"max size", MaxFileSizeBytes, false, ""},
		{"too large", MaxFileSizeBytes + 1, true, errors.ValidationFileTooLarge},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateFileSize(tt.size)
			if tt.wantErr {
				assert.Error(t, err)
				if appErr, ok := err.(*errors.AppError); ok {
					assert.Equal(t, tt.wantCode, appErr.Code)
				}
			} else {
				assert.NoError(t, err)
			}
		})
	}
}

func TestValidateRegistration(t *testing.T) {
	tests := []struct {
		name     string
		email    string
		password string
		userName string
		phone    string
		wantErr  bool
	}{
		{"valid", "test@example.com", "Abcd1234", "John Doe", "+1234567890", false},
		{"invalid email", "invalid", "Abcd1234", "John Doe", "+1234567890", true},
		{"invalid password", "test@example.com", "weak", "John Doe", "+1234567890", true},
		{"invalid name", "test@example.com", "Abcd1234", "", "+1234567890", true},
		{"invalid phone", "test@example.com", "Abcd1234", "John Doe", "abc", true},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateRegistration(tt.email, tt.password, tt.userName, tt.phone)
			if tt.wantErr {
				assert.Error(t, err)
			} else {
				assert.NoError(t, err)
			}
		})
	}
}