/*
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 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *    https://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 */
package scaffoldingfields

import grails.gorm.transactions.Rollback
import grails.plugin.geb.ContainerGebSpec
import grails.testing.mixin.integration.Integration

/**
 * Comprehensive functional tests for relationship handling in scaffolded views.
 * Tests belongsTo, hasMany, manyToMany, and embedded relationship rendering.
 * 
 * Relationships tested:
 * - belongsTo: Employee belongs to Department (renders as select dropdown)
 * - hasMany (parent): Department has many Employees (renders as list on show page)
 * - hasMany (child): Employee has many Projects (renders as multi-select)
 * - manyToMany: Project and Employee bidirectional relationship
 * - embedded: Employee has embedded Address object
 */
@Rollback
@Integration
class RelationshipsFunctionalSpec extends ContainerGebSpec {

    /**
     * Helper to submit the form
     */
    private void submitForm() {
        def submitButton = $('input[type="submit"]').find { it.displayed } ?: 
                          $('button[type="submit"]').find { it.displayed }
        submitButton?.click()
    }

    // ==================== BELONGSTO RELATIONSHIP ====================

    def "BelongsTo renders as select dropdown with existing entities"() {
        when: "navigating to employee create page"
        go '/employee/create'
        waitFor(10) { $('form').displayed }

        then: "department select is present"
        def deptSelect = $('select[name="department.id"]') ?: $('select[name="department"]')
        deptSelect.displayed

        and: "select contains options (null option + departments)"
        def options = deptSelect.find('option')
        options.size() > 1

        and: "options include departments from bootstrap data"
        def optionTexts = options*.text()
        optionTexts.any { it.contains('Engineering') || it.contains('Marketing') || it.contains('Sales') }
    }

    def "BelongsTo select includes null/empty option for nullable associations"() {
        when: "navigating to employee create page"
        go '/employee/create'
        waitFor(10) { $('form').displayed }

        then: "department select has an empty/null option"
        def deptSelect = $('select[name="department.id"]') ?: $('select[name="department"]')
        def options = deptSelect.find('option')
        
        // First option is typically empty for nullable associations
        options.first().text().trim() == '' || options.first().value() == ''
    }

    def "Can select belongsTo association when creating entity"() {
        given: "navigating to employee create page"
        go '/employee/create'
        waitFor(10) { $('form').displayed }

        when: "selecting a department and filling required fields"
        def deptSelect = $('select[name="department.id"]') ?: $('select[name="department"]')
        deptSelect.find('option', text: contains('Engineering')).click()
        $('input[name="firstName"]').value('Related')
        $('input[name="lastName"]').value('Employee')
        $('input[name="email"]').value("related.employee.${System.currentTimeMillis()}@example.com")

        and: "submitting the form"
        submitForm()

        then: "employee is created successfully with department association"
        waitFor(10) {
            currentUrl.contains('/employee/show/') ||
            currentUrl.contains('/employee/index')
        }

        and: "department is shown on the page"
        if (currentUrl.contains('/employee/show/')) {
            $('body').text().contains('Engineering')
        }
    }

    def "Show page displays belongsTo association as link or text"() {
        when: "navigating to an employee show page with department"
        go '/employee/show/1'

        then: "the department label and the associated department name are both rendered"
        // Poll the rendered content rather than capturing the body once: the layout's
        // "Skip to content" shell is present before the GSP body content is merged in,
        // so a single early capture can miss the association value.
        waitFor(10) {
            def pageContent = $('body').text()
            (pageContent.contains('Department') || pageContent.contains('department')) &&
                    (pageContent.contains('Engineering') || pageContent.contains('Marketing') || pageContent.contains('Sales'))
        }
    }

    def "Edit page preserves belongsTo selection"() {
        when: "navigating to employee edit page"
        go '/employee/edit/1'
        waitFor(10) { $('form').displayed }

        then: "department select has a value selected"
        def deptSelect = $('select[name="department"], select[name="department.id"]')
        deptSelect.displayed

        and: "the selected option matches the employee's department"
        def selectedOption = deptSelect.find('option:checked') ?: deptSelect.find('option[selected]')
        selectedOption.size() > 0 || deptSelect.value() != ''
    }

    def "Can change belongsTo association on edit"() {
        given: "navigating to employee edit page"
        go '/employee/edit/1'
        waitFor(10) { $('form').displayed }

        when: "changing the department selection"
        def deptSelect = $('select[name="department"], select[name="department.id"]')
        def currentValue = deptSelect.value()
        
        // Select a different department
        def options = deptSelect.find('option').findAll { it.value() != '' && it.value() != currentValue }
        if (options.size() > 0) {
            options.first().click()
        }
        submitForm()

        then: "update succeeds"
        waitFor(10) {
            currentUrl.contains('/employee/show/') ||
            currentUrl.contains('/employee/index') ||
            currentUrl.contains('/employee/edit/')
        }
    }

    // ==================== HASMANY RELATIONSHIP (Parent Side) ====================

    def "Department show page displays hasMany employees list"() {
        when: "navigating to a department show page"
        go '/department/show/1'
        waitFor(10) { $('body').displayed }

        then: "page displays employees section"
        def pageContent = $('body').text()
        pageContent.contains('Employees') || pageContent.contains('employees')

        and: "employee names are visible"
        pageContent.contains('John') || pageContent.contains('Jane') || $('a[href*="/employee/show/"]').size() > 0
    }

    def "Department list page renders correctly with hasMany relationship"() {
        when: "navigating to department list"
        go '/department/index'
        waitFor(10) { $('table').displayed }

        then: "page displays department list correctly"
        title.contains('Department')
        $('table').displayed

        and: "department names are visible"
        def tableContent = $('table').text()
        tableContent.contains('Engineering') || tableContent.contains('Marketing') || tableContent.contains('Sales')
    }

    def "HasMany collection is displayed as list or table on show page"() {
        when: "navigating to department show page"
        go '/department/show/1'
        waitFor(10) { $('body').displayed }

        then: "employees are rendered as list items or links"
        // Check for various ways employees might be displayed
        $('ul li a[href*="/employee/"]').size() > 0 ||
        $('a[href*="/employee/show/"]').size() > 0 ||
        $('body').text().contains('John') ||
        $('body').text().contains('Employees')
    }

    // ==================== HASMANY RELATIONSHIP (Child Side - Multi-select) ====================

    def "HasMany on child side renders as multi-select"() {
        when: "navigating to employee create/edit page"
        go '/employee/create'
        waitFor(10) { $('form').displayed }

        then: "projects field is displayed as multi-select if present"
        def projectsSelect = $('select[name="projects"]')
        if (projectsSelect.displayed) {
            // Multi-select should have multiple attribute
            projectsSelect.attr('multiple') != null || projectsSelect.@multiple == 'multiple'
        } else {
            true  // Field may not be shown on create
        }
    }

    def "Can select multiple hasMany items on edit page"() {
        given: "navigating to employee edit page"
        go '/employee/edit/1'
        waitFor(10) { $('form').displayed }

        when: "checking projects multi-select"
        def projectsSelect = $('select[name="projects"]')

        then: "multi-select is displayed and has options"
        if (projectsSelect.displayed) {
            projectsSelect.find('option').size() >= 0
        } else {
            true
        }
    }

    def "HasMany multi-select shows available options from database"() {
        when: "navigating to employee edit page"
        go '/employee/edit/1'
        waitFor(10) { $('form').displayed }

        then: "projects select shows available projects"
        def projectsSelect = $('select[name="projects"]')
        if (projectsSelect.displayed) {
            def options = projectsSelect.find('option')
            options.size() > 0 || true  // May have no projects
        } else {
            true
        }
    }

    // ==================== MANYTOMANY RELATIONSHIP ====================

    def "Project shows many-to-many employees"() {
        when: "navigating to project show page"
        go '/project/show/1'
        waitFor(10) { $('body').displayed }

        then: "employees may be displayed"
        def pageContent = $('body').text()
        pageContent.contains('Employees') || pageContent.contains('employees')
    }

    def "Project edit allows selecting multiple employees"() {
        when: "navigating to project edit page"
        go '/project/edit/1'
        waitFor(10) { $('form').displayed }

        then: "employees multi-select is present"
        def employeesSelect = $('select[name="employees"]')
        if (employeesSelect.displayed) {
            employeesSelect.find('option').size() >= 0
        } else {
            true  // Field may not be displayed
        }
    }

    def "Project create page shows employees multi-select"() {
        when: "navigating to project create page"
        go '/project/create'
        waitFor(10) { $('form').displayed }

        then: "employees field may be present as multi-select"
        def employeesSelect = $('select[name="employees"]')
        // On create, hasMany may or may not be shown
        employeesSelect.displayed || true
    }

    // ==================== EMBEDDED RELATIONSHIP ====================

    def "Embedded address fields render inline with dotted notation"() {
        when: "navigating to employee create page"
        go '/employee/create'
        waitFor(10) { $('form').displayed }

        then: "embedded address fields are present with dotted names"
        def streetField = $('input[name="address.street"]')
        def cityField = $('input[name="address.city"]')
        def postalCodeField = $('input[name="address.postalCode"]')
        def countryField = $('input[name="address.country"]')

        streetField.displayed
        cityField.displayed
        postalCodeField.displayed
        countryField.displayed
    }

    def "Embedded fields are grouped together in form"() {
        when: "navigating to employee create page"
        go '/employee/create'
        waitFor(10) { $('form').displayed }

        then: "address fields are present"
        // Verify all embedded fields exist
        $('input[name="address.street"]').displayed
        $('input[name="address.city"]').displayed
    }

    def "Can save entity with embedded object data"() {
        given: "navigating to employee create page"
        go '/employee/create'
        waitFor(10) { $('form').displayed }

        when: "filling required fields and embedded address"
        $('input[name="firstName"]').value('Embedded')
        $('input[name="lastName"]').value('AddressTest')
        $('input[name="email"]').value("embedded.address.${System.currentTimeMillis()}@example.com")

        $('input[name="address.street"]').value('789 Test Street')
        $('input[name="address.city"]').value('Test City')
        $('input[name="address.postalCode"]').value('12345')
        $('input[name="address.country"]').value('Test Country')

        and: "submitting the form"
        submitForm()

        then: "entity is created successfully"
        waitFor(10) {
            currentUrl.contains('/employee/show/') ||
            currentUrl.contains('/employee/index')
        }
    }

    def "Show page displays embedded object properties"() {
        when: "navigating to employee show page with address"
        go '/employee/show/1'
        waitFor(10) { $('body').displayed }

        then: "address fields are displayed"
        def pageContent = $('body').text()
        // Check for address-related content
        pageContent.contains('Address') || pageContent.contains('address') ||
        pageContent.contains('Street') || pageContent.contains('City') ||
        pageContent.contains('New York') || pageContent.contains('123')
    }

    def "Edit page preserves embedded object values"() {
        when: "navigating to employee edit page"
        go '/employee/edit/1'
        waitFor(10) { $('form').displayed }

        then: "embedded address fields retain their values"
        def streetField = $('input[name="address.street"]')
        def cityField = $('input[name="address.city"]')
        
        // Fields should have values if employee has address
        streetField.displayed
        cityField.displayed
    }

    def "Can update embedded object values"() {
        given: "navigating to employee edit page"
        go '/employee/edit/1'
        waitFor(10) { $('form').displayed }

        when: "updating embedded address values"
        def streetField = $('input[name="address.street"]')
        if (streetField.displayed) {
            streetField.value('999 Updated Street')
        }
        submitForm()

        then: "update succeeds"
        waitFor(10) {
            currentUrl.contains('/employee/show/') ||
            currentUrl.contains('/employee/index') ||
            currentUrl.contains('/employee/edit/')
        }
    }

    // ==================== RELATIONSHIP CONSISTENCY ====================

    def "Creating employee with department creates bidirectional relationship"() {
        given: "note initial state"
        go '/department/show/1'
        waitFor(10) { $('body').displayed }
        def initialContent = $('body').text()

        when: "creating new employee in engineering department"
        go '/employee/create'
        waitFor(10) { $('form').displayed }
        
        def deptSelect = $('select[name="department"], select[name="department.id"]')
        deptSelect.find('option', text: contains('Engineering')).click()
        $('input[name="firstName"]').value('NewEngineer')
        $('input[name="lastName"]').value('ForConsistency')
        $('input[name="email"]').value("new.engineer.consistency.${System.currentTimeMillis()}@example.com")
        submitForm()

        then: "employee was created successfully"
        waitFor(10) {
            currentUrl.contains('/employee/show/') ||
            currentUrl.contains('/employee/index')
        }
    }

    def "Removing department association from employee works correctly"() {
        given: "navigating to employee edit page"
        go '/employee/edit/1'
        waitFor(10) { $('form').displayed }

        when: "selecting empty department option"
        def deptSelect = $('select[name="department"], select[name="department.id"]')
        def emptyOption = deptSelect.find('option').find { it.value() == '' || it.text().trim() == '' }
        if (emptyOption) {
            emptyOption.click()
        }
        submitForm()

        then: "update succeeds"
        waitFor(10) {
            currentUrl.contains('/employee/show/') ||
            currentUrl.contains('/employee/index') ||
            currentUrl.contains('/employee/edit/')
        }
    }

    // ==================== NULL ASSOCIATION HANDLING ====================

    def "Can create entity without selecting optional belongsTo association"() {
        given: "navigating to employee create page"
        go '/employee/create'
        waitFor(10) { $('form').displayed }

        when: "filling required fields without selecting department"
        $('input[name="firstName"]').value('NoDept')
        $('input[name="lastName"]').value('EmployeeTest')
        $('input[name="email"]').value("nodept.employee.${System.currentTimeMillis()}@example.com")
        // Explicitly don't select a department

        and: "submitting the form"
        submitForm()

        then: "entity is created without association"
        waitFor(10) {
            currentUrl.contains('/employee/show/') ||
            currentUrl.contains('/employee/index')
        }
    }

    def "Show page handles null belongsTo association gracefully"() {
        when: "navigating to employee show page"
        // Bob Wilson (employee 3) may not have all associations
        go '/employee/show/3'
        waitFor(10) { $('body').displayed }

        then: "page renders without errors"
        title.contains('Employee') || title.contains('Show')
        $('body').text().contains('Wilson') || $('body').text().contains('Bob')
    }

    def "Show page handles empty hasMany collection gracefully"() {
        when: "navigating to a department that might have no employees"
        go '/department/show/3'
        waitFor(10) { $('body').displayed }

        then: "page renders without errors even if no employees"
        title.contains('Department') || title.contains('Show')
        $('body').displayed
    }

    def "Edit page handles null associations gracefully"() {
        when: "navigating to employee edit page"
        go '/employee/edit/3'
        waitFor(10) { $('form').displayed }

        then: "form displays correctly with empty/null selections"
        $('form').displayed
        $('input[name="firstName"]').displayed
    }

    // ==================== ASSOCIATION DISPLAY FORMATS ====================

    def "BelongsTo association displays toString representation"() {
        when: "navigating to employee show page"
        go '/employee/show/1'
        waitFor(10) { $('body').displayed }

        then: "department field is displayed on the page"
        def pageContent = $('body').text()
        // Department field should be present (may or may not have a value depending on data)
        pageContent.contains('Department') || 
        pageContent.contains('department') ||
        pageContent.contains('Engineering') || 
        pageContent.contains('Marketing') || 
        pageContent.contains('Sales')
    }

    def "HasMany items display as links to associated entities"() {
        when: "navigating to department show page"
        go '/department/show/1'
        waitFor(10) { $('body').displayed }

        then: "employees are shown as links or with their toString"
        // Employees should be clickable links or display their names
        $('a[href*="/employee/show/"]').size() > 0 ||
        $('body').text().contains('John') ||
        $('body').text().contains('Jane')
    }

    // ==================== CASCADE BEHAVIOR ====================

    def "Deleting department shows appropriate warning or behavior"() {
        when: "navigating to department show page"
        go '/department/show/1'
        waitFor(10) { $('body').displayed }

        then: "delete button or form is present"
        // There should be a way to delete (even if it warns about employees)
        $('button[type="submit"]').find { it.text()?.toLowerCase()?.contains('delete') } ||
        $('input[type="submit"]').find { it.value()?.toLowerCase()?.contains('delete') } ||
        $('form[action*="delete"]').displayed ||
        $('a[href*="delete"]').displayed ||
        true  // Some scaffolding may not show delete on show page
    }
}
