import {
  ComponentType,
  type TextFieldComponent,
  type UkAddressFieldComponent
} from '@defra/forms-model'

import { ComponentCollection } from '~/src/server/plugins/engine/components/ComponentCollection.js'
import { UkAddressField } from '~/src/server/plugins/engine/components/UkAddressField.js'
import {
  getAnswer,
  type Field
} from '~/src/server/plugins/engine/components/helpers/components.js'
import { type ViewModel } from '~/src/server/plugins/engine/components/types.js'
import { FormModel } from '~/src/server/plugins/engine/models/FormModel.js'
import {
  type FormPayload,
  type FormState
} from '~/src/server/plugins/engine/types.js'
import definition from '~/test/form/definitions/blank.js'

describe('UkAddressField', () => {
  let model: FormModel

  beforeEach(() => {
    model = new FormModel(definition, {
      basePath: 'test'
    })
  })

  describe('Defaults', () => {
    let def: UkAddressFieldComponent
    let collection: ComponentCollection
    let field: Field

    beforeEach(() => {
      def = {
        title: 'Example UK address',
        name: 'myComponent',
        type: ComponentType.UkAddressField,
        options: {}
      } satisfies UkAddressFieldComponent

      collection = new ComponentCollection([def], { model })
      field = collection.fields[0]
    })

    describe('Schema', () => {
      it('uses collection titles as labels', () => {
        const { formSchema } = collection
        const { keys } = formSchema.describe()

        expect(keys).toHaveProperty(
          'myComponent__addressLine1',
          expect.objectContaining({
            flags: expect.objectContaining({ label: 'Address line 1' })
          })
        )

        expect(keys).toHaveProperty(
          'myComponent__addressLine2',
          expect.objectContaining({
            flags: expect.objectContaining({ label: 'Address line 2' })
          })
        )

        expect(keys).toHaveProperty(
          'myComponent__town',
          expect.objectContaining({
            flags: expect.objectContaining({ label: 'Town or city' })
          })
        )

        expect(keys).toHaveProperty(
          'myComponent__county',
          expect.objectContaining({
            flags: expect.objectContaining({ label: 'County' })
          })
        )

        expect(keys).toHaveProperty(
          `myComponent__postcode`,
          expect.objectContaining({
            flags: expect.objectContaining({ label: 'Postcode' })
          })
        )
      })

      it('uses collection names as keys', () => {
        const { formSchema } = collection
        const { keys } = formSchema.describe()

        expect(field.keys).toEqual([
          'myComponent',
          'myComponent__uprn',
          'myComponent__addressLine1',
          'myComponent__addressLine2',
          'myComponent__town',
          'myComponent__county',
          'myComponent__postcode'
        ])

        expect(field.collection?.keys).not.toHaveProperty('myComponent')

        for (const key of field.collection?.keys ?? []) {
          expect(keys).toHaveProperty(key)
        }
      })

      it('is required by default', () => {
        const { formSchema } = collection
        const { keys } = formSchema.describe()

        expect(keys).toHaveProperty(
          'myComponent__addressLine1',
          expect.objectContaining({
            flags: expect.objectContaining({ presence: 'required' })
          })
        )

        expect(keys).toHaveProperty(
          'myComponent__addressLine2',
          expect.objectContaining({
            allow: [''], // Required but empty string is allowed
            flags: expect.objectContaining({ presence: 'required' })
          })
        )

        expect(keys).toHaveProperty(
          'myComponent__town',
          expect.objectContaining({
            flags: expect.objectContaining({ presence: 'required' })
          })
        )

        expect(keys).toHaveProperty(
          'myComponent__county',
          expect.objectContaining({
            allow: [''], // Required but empty string is allowed
            flags: expect.objectContaining({ presence: 'required' })
          })
        )

        expect(keys).toHaveProperty(
          `myComponent__postcode`,
          expect.objectContaining({
            flags: expect.objectContaining({ presence: 'required' })
          })
        )
      })

      it('is optional when configured', () => {
        const collectionOptional = new ComponentCollection(
          [
            {
              title: 'Example UK address',
              name: 'myComponent',
              type: ComponentType.UkAddressField,
              options: { required: false }
            }
          ],
          { model }
        )

        const { formSchema } = collectionOptional
        const { keys } = formSchema.describe()

        expect(keys).toHaveProperty(
          'myComponent__addressLine1',
          expect.objectContaining({ allow: [''] })
        )

        expect(keys).toHaveProperty(
          'myComponent__addressLine2',
          expect.objectContaining({ allow: [''] })
        )

        expect(keys).toHaveProperty(
          'myComponent__town',
          expect.objectContaining({ allow: [''] })
        )

        expect(keys).toHaveProperty(
          'myComponent__county',
          expect.objectContaining({ allow: [''] })
        )

        expect(keys).toHaveProperty(
          `myComponent__postcode`,
          expect.objectContaining({ allow: [''] })
        )

        const result = collectionOptional.validate(
          getFormData({
            addressLine1: '',
            addressLine2: '',
            town: '',
            county: '',
            postcode: '',
            uprn: ''
          })
        )

        expect(result.errors).toBeUndefined()
      })

      it('accepts valid values', () => {
        const result1 = collection.validate(
          getFormData({
            addressLine1: 'Richard Fairclough House',
            addressLine2: 'Knutsford Road',
            town: 'Warrington',
            county: 'Cheshire',
            postcode: 'WA4 1HT',
            uprn: ''
          })
        )

        const result2 = collection.validate(
          getFormData({
            addressLine1: 'Richard Fairclough House',
            addressLine2: '', // Optional field
            town: 'Warrington',
            county: '', // Optional field
            postcode: 'WA4 1HT',
            uprn: ''
          })
        )

        expect(result1.errors).toBeUndefined()
        expect(result2.errors).toBeUndefined()
      })

      it('adds errors for empty value', () => {
        const result = collection.validate(
          getFormData({
            addressLine1: '',
            addressLine2: '',
            town: '',
            county: '',
            postcode: '',
            uprn: ''
          })
        )

        expect(result.errors).toEqual([
          expect.objectContaining({
            text: 'Enter address line 1'
          }),
          expect.objectContaining({
            text: 'Enter town or city'
          }),
          expect.objectContaining({
            text: 'Enter postcode'
          })
        ])
      })

      it('adds errors for invalid values', () => {
        const result1 = collection.validate(getFormData({ unknown: 'invalid' }))

        const result2 = collection.validate(
          getFormData({
            addressLine1: ['invalid'],
            addressLine2: ['invalid'],
            town: ['invalid'],
            county: ['invalid'],
            postcode: ['invalid']
          })
        )

        const result3 = collection.validate(
          getFormData({
            addressLine1: 'invalid',
            addressLine2: 'invalid',
            town: 'invalid',
            county: 'invalid',
            postcode: 'invalid'
          })
        )

        expect(result1.errors).toBeTruthy()
        expect(result2.errors).toBeTruthy()
        expect(result3.errors).toBeTruthy()
      })

      it('should ensure all address fields have valid autocomplete values', () => {
        const ukAddressField = new UkAddressField(
          {
            type: ComponentType.UkAddressField,
            name: 'testAddress',
            title: 'Test Address',
            options: {
              required: true,
              hideTitle: false
            }
          },
          {
            model
          }
        )

        const expectedAutocompleteValues = [
          'address-line1',
          'address-line2',
          'address-level1',
          'address-level2',
          'postal-code'
        ]

        ukAddressField.collection.components.slice(1).forEach((component) => {
          const addressFieldOptions =
            component.options as TextFieldComponent['options']

          expect(expectedAutocompleteValues).toContain(
            addressFieldOptions.autocomplete
          )
        })
      })
    })

    describe('State', () => {
      const address: FormPayload = {
        addressLine1: 'Richard Fairclough House',
        addressLine2: 'Knutsford Road',
        town: 'Warrington',
        county: 'Cheshire',
        postcode: 'WA4 1HT',
        uprn: '123456789'
      }

      it('returns text from state', () => {
        const state1 = getFormState(address)
        const state2 = getFormState({})

        const answer1 = getAnswer(field, state1)
        const answer2 = getAnswer(field, state2)

        expect(answer1).toBe(
          'Richard Fairclough House<br>Knutsford Road<br>Warrington<br>Cheshire<br>WA4 1HT<br>'
        )

        expect(answer2).toBe('')
      })

      it('returns payload from state', () => {
        const state1 = getFormState(address)
        const state2 = getFormState({})

        const payload1 = field.getFormDataFromState(state1)
        const payload2 = field.getFormDataFromState(state2)

        expect(payload1).toEqual(getFormData(address))
        expect(payload2).toEqual(getFormData({}))
      })

      it('returns value from state', () => {
        const state1 = getFormState(address)
        const state2 = getFormState({})

        const value1 = field.getFormValueFromState(state1)
        const value2 = field.getFormValueFromState(state2)

        expect(value1).toEqual(address)
        expect(value2).toBeUndefined()
      })

      it('returns context for conditions and form submission', () => {
        const state1 = getFormState(address)
        const state2 = getFormState({})

        const value1 = field.getContextValueFromState(state1)
        const value2 = field.getContextValueFromState(state2)

        expect(value1).toEqual([
          'Richard Fairclough House',
          'Knutsford Road',
          'Warrington',
          'Cheshire',
          'WA4 1HT'
        ])

        expect(value2).toBeNull()
      })

      it('returns state from payload', () => {
        const payload1 = getFormData(address)
        const payload2 = getFormData({})

        const value1 = field.getStateFromValidForm(payload1)
        const value2 = field.getStateFromValidForm(payload2)

        expect(value1).toEqual(getFormState(address))
        expect(value2).toEqual(getFormState({}))
      })
    })

    describe('View model', () => {
      const address: FormPayload = {
        addressLine1: 'Richard Fairclough House',
        addressLine2: 'Knutsford Road',
        town: 'Warrington',
        county: 'Cheshire',
        postcode: 'WA4 1HT'
      }

      it('sets Nunjucks component defaults', () => {
        const payload = getFormData(address)
        const viewModel = field.getViewModel(payload)

        expect(viewModel).toEqual(
          expect.objectContaining({
            label: { text: def.title },
            name: 'myComponent',
            id: 'myComponent',
            value: undefined,
            components: expect.arrayContaining([
              expect.objectContaining({
                model: getViewModel(address, 'addressLine1', {
                  label: { text: 'Address line 1' },
                  attributes: { autocomplete: 'address-line1' }
                })
              }),

              expect.objectContaining({
                model: getViewModel(address, 'addressLine2', {
                  label: { text: 'Address line 2 (optional)' },
                  attributes: { autocomplete: 'address-line2' },
                  value: address.addressLine2
                })
              }),

              expect.objectContaining({
                model: getViewModel(address, 'town', {
                  label: { text: 'Town or city' },
                  classes: 'govuk-!-width-two-thirds',
                  attributes: { autocomplete: 'address-level2' },
                  value: address.town
                })
              }),

              expect.objectContaining({
                model: getViewModel(address, 'county', {
                  label: { text: 'County (optional)' },
                  attributes: { autocomplete: 'address-level1' },
                  value: address.county
                })
              }),

              expect.objectContaining({
                model: getViewModel(address, 'postcode', {
                  label: { text: 'Postcode' },
                  classes: 'govuk-input--width-10',
                  attributes: { autocomplete: 'postal-code' },
                  value: address.postcode
                })
              })
            ])
          })
        )
      })

      it('sets Nunjucks component fieldset', () => {
        const payload = getFormData(address)
        const viewModel = field.getViewModel(payload)

        expect(viewModel.fieldset).toEqual({
          legend: {
            text: def.title,
            classes: 'govuk-fieldset__legend--m'
          }
        })
      })
    })

    describe('AllPossibleErrors', () => {
      it('should return errors', () => {
        const errors = field.getAllPossibleErrors()
        expect(errors.baseErrors).not.toBeEmpty()
        expect(errors.advancedSettingsErrors).toBeEmpty()
      })
    })
  })

  describe('Validation', () => {
    const address: FormPayload = {
      addressLine1: 'Richard Fairclough House',
      addressLine2: 'Knutsford Road',
      town: 'Warrington',
      county: 'Cheshire',
      postcode: 'WA4 1HT',
      uprn: ''
    }

    const addressLine1Invalid =
      'Address line 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000'

    const addressLine2Invalid =
      'Address line 2000000000000000000000000000000000000000000000000000000000000000000000000000000000000000'

    const townInvalid =
      'Town 000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000'

    const countyInvalid =
      'County 0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000'

    const postcodeInvalid = '111 XX2'

    describe.each([
      {
        description: 'Trim empty spaces',
        component: {
          title: 'Example UK address',
          name: 'myComponent',
          type: ComponentType.UkAddressField,
          options: {}
        } satisfies UkAddressFieldComponent,
        assertions: [
          {
            input: getFormData({
              addressLine1: ' Richard Fairclough House',
              addressLine2: ' Knutsford Road',
              town: ' Warrington',
              county: 'Cheshire',
              postcode: ' WA4 1HT',
              uprn: ''
            }),
            output: {
              value: getFormData(address),
              errors: undefined
            }
          },
          {
            input: getFormData({
              addressLine1: 'Richard Fairclough House ',
              addressLine2: 'Knutsford Road ',
              town: 'Warrington ',
              county: 'Cheshire ',
              postcode: 'WA4 1HT ',
              uprn: ''
            }),
            output: {
              value: getFormData(address),
              errors: undefined
            }
          },
          {
            input: getFormData({
              addressLine1: ' Richard Fairclough House \n\n',
              addressLine2: ' Knutsford Road \n\n',
              town: ' Warrington \n\n',
              county: ' Cheshire \n\n',
              postcode: ' WA4 1HT \n\n',
              uprn: ''
            }),
            output: {
              value: getFormData(address),
              errors: undefined
            }
          }
        ]
      },
      {
        description: 'Out of range values',
        component: {
          title: 'Example UK address',
          name: 'myComponent',
          type: ComponentType.UkAddressField,
          options: {}
        } satisfies UkAddressFieldComponent,
        assertions: [
          {
            input: getFormData({
              addressLine1: addressLine1Invalid,
              addressLine2: 'Knutsford Road',
              town: 'Warrington',
              county: 'Cheshire',
              postcode: 'WA4 1HT',
              uprn: ''
            }),
            output: {
              value: getFormData({
                addressLine1: addressLine1Invalid,
                addressLine2: 'Knutsford Road',
                town: 'Warrington',
                county: 'Cheshire',
                postcode: 'WA4 1HT',
                uprn: ''
              }),
              errors: [
                expect.objectContaining({
                  text: 'Address line 1 must be 100 characters or less'
                })
              ]
            }
          },
          {
            input: getFormData({
              addressLine1: 'Richard Fairclough House',
              addressLine2: addressLine2Invalid,
              town: 'Warrington',
              county: 'Cheshire',
              postcode: 'WA4 1HT',
              uprn: ''
            }),
            output: {
              value: getFormData({
                addressLine1: 'Richard Fairclough House',
                addressLine2: addressLine2Invalid,
                town: 'Warrington',
                county: 'Cheshire',
                postcode: 'WA4 1HT',
                uprn: ''
              }),
              errors: [
                expect.objectContaining({
                  text: 'Address line 2 must be 100 characters or less'
                })
              ]
            }
          },
          {
            input: getFormData({
              addressLine1: 'Richard Fairclough House',
              addressLine2: 'Knutsford Road',
              town: townInvalid,
              county: 'Cheshire',
              postcode: 'WA4 1HT',
              uprn: ''
            }),
            output: {
              value: getFormData({
                addressLine1: 'Richard Fairclough House',
                addressLine2: 'Knutsford Road',
                town: townInvalid,
                county: 'Cheshire',
                postcode: 'WA4 1HT',
                uprn: ''
              }),
              errors: [
                expect.objectContaining({
                  text: 'Town or city must be 100 characters or less'
                })
              ]
            }
          },
          {
            input: getFormData({
              addressLine1: 'Richard Fairclough House',
              addressLine2: 'Knutsford Road',
              town: 'Warrington',
              county: countyInvalid,
              postcode: 'WA4 1HT',
              uprn: ''
            }),
            output: {
              value: getFormData({
                addressLine1: 'Richard Fairclough House',
                addressLine2: 'Knutsford Road',
                town: 'Warrington',
                county: countyInvalid,
                postcode: 'WA4 1HT',
                uprn: ''
              }),
              errors: [
                expect.objectContaining({
                  text: 'County must be 100 characters or less'
                })
              ]
            }
          },
          {
            input: getFormData({
              addressLine1: 'Richard Fairclough House',
              addressLine2: 'Knutsford Road',
              town: 'Warrington',
              county: 'Cheshire',
              postcode: postcodeInvalid,
              uprn: ''
            }),
            output: {
              value: getFormData({
                addressLine1: 'Richard Fairclough House',
                addressLine2: 'Knutsford Road',
                town: 'Warrington',
                county: 'Cheshire',
                postcode: postcodeInvalid,
                uprn: ''
              }),
              errors: [
                expect.objectContaining({
                  text: 'Enter a valid postcode'
                })
              ]
            }
          },
          {
            input: getFormData({
              addressLine1: '',
              addressLine2: '',
              town: '',
              county: '',
              postcode: postcodeInvalid,
              uprn: ''
            }),
            output: {
              value: getFormData({
                addressLine1: '',
                addressLine2: '',
                town: '',
                county: '',
                postcode: postcodeInvalid,
                uprn: ''
              }),
              errors: [
                expect.objectContaining({
                  text: 'Enter address line 1'
                }),
                expect.objectContaining({
                  text: 'Enter town or city'
                }),
                expect.objectContaining({
                  text: 'Enter a valid postcode'
                })
              ]
            }
          }
        ]
      }
    ])('$description', ({ component: def, assertions }) => {
      let collection: ComponentCollection

      beforeEach(() => {
        collection = new ComponentCollection([def], { model })
      })

      it.each([...assertions])(
        'validates custom example',
        ({ input, output }) => {
          const result = collection.validate(input)
          expect(result).toEqual(output)

          const errors = collection.getErrors(result.errors)
          expect(errors).toEqual(output.errors)
        }
      )
    })
  })
})

/**
 * UK address field view model
 */
function getViewModel(
  address: FormPayload,
  name: string,
  overrides?: Partial<ViewModel>
): Partial<ViewModel> {
  const payload = getFormData(address)
  const fieldName = `myComponent__${name}`
  const fieldClasses = overrides?.classes ?? undefined
  const fieldAttributes = overrides?.attributes ?? expect.any(Object)

  return {
    label: expect.objectContaining(
      overrides?.label ?? {
        text: expect.any(String)
      }
    ),
    name: fieldName,
    id: fieldName,
    value: payload[fieldName],
    classes: fieldClasses,
    attributes: fieldAttributes
  }
}

/**
 * UK address form data
 */
function getFormData(address: FormPayload): FormPayload {
  return {
    myComponent__addressLine1: address.addressLine1,
    myComponent__addressLine2: address.addressLine2,
    myComponent__town: address.town,
    myComponent__county: address.county,
    myComponent__postcode: address.postcode,
    myComponent__uprn: address.uprn
  }
}

/**
 * UK address session state
 */
function getFormState(address: FormPayload): FormState {
  const [addressLine1, addressLine2, town, county, postcode, uprn] =
    Object.values(getFormData(address))

  return {
    myComponent__addressLine1: addressLine1 ?? null,
    myComponent__addressLine2: addressLine2 ?? null,
    myComponent__town: town ?? null,
    myComponent__county: county ?? null,
    myComponent__postcode: postcode ?? null,
    myComponent__uprn: uprn ?? null
  }
}