/**
 * The browser half: the two keys it binds, and the fields it stages.
 *
 * This file exists because of a bug that no host-side test could catch. Marking
 * the schema's fields `volatile()` makes the Host *serve* the namespace, but the
 * Plugins page draws only what a browser half registers — so the plugin showed no
 * settings card at all, and every host-side test passed.
 *
 * The wiring is therefore the thing worth testing, and the two keys are the trap:
 * the settings DOCUMENT is keyed by the profile entry id (`facet-policy`) while
 * the CARD is keyed by the package name (`dsh-facet`). Every sibling plugin
 * happens to name those identically, which is exactly why this drifted. A card
 * bound to the wrong id renders, saves, and writes nowhere.
 *
 * `client/client.js` is a `window.__ModuleLoader__` module rather than an ES
 * module — that is how the harness loads a browser half without a bundler — so
 * the test stands up the two globals it reads and drives it from there.
 */

import assert from 'node:assert/strict'
import { readFile } from 'node:fs/promises'
import { test } from 'node:test'

import { Config } from '../index.js'

/** Load the browser half with `window` and `require` faked, as the seed would. */
async function loadClient() {
  const source = await readFile(new URL('../client/client.js', import.meta.url), 'utf8')

  /** Every spec a card staged, in construction order. */
  const staged = []

  const primitives = {
    SettingsForm: 'SettingsForm',
    SettingsValueField: 'SettingsValueField',
    SegmentedControl: 'SegmentedControl',
    /** Stands in for the real model: records the specs and answers with the value. */
    SettingsFormModel: class {
      constructor(scope, specs) {
        this.scope = scope
        this.specs = specs
        staged.push(...specs)
      }
      bind(project) {
        this.project = project
        return { project }
      }
      shell() {
        return { available: true, writable: true, dirty: false, invalid: false, saving: false, failed: false }
      }
      field(name) {
        const spec = this.specs.find((candidate) => candidate.field === name)
        return { text: spec?.format(this.scope.value?.[name]) ?? '', overridden: false, invalid: false }
      }
      actions() {
        return { edit: () => {}, resetField: () => {}, save: () => {}, discard: () => {} }
      }
      dispose() {}
    },
  }

  const require = (id) => {
    if (id === 'react') return { createElement: (type, props, ...children) => ({ type, props, children }) }
    if (id === '@deepseek-ai/dsh-client-ui-primitives') return primitives
    throw new Error(`client.js required an unexpected module: ${id}`)
  }

  let registered
  const loader = { load: (value) => (registered = value) }
  // eslint-disable-next-line no-new-func -- the file is a ModuleLoader script, not an ES module.
  new Function('window', 'require', source)({ __ModuleLoader__: loader }, require)

  assert.notEqual(registered, undefined, 'client.js never called window.__ModuleLoader__.load')
  return { module: registered.factory(require), staged, primitives }
}

/** Drive `apply` against a fake slot/configForms surface and report what it did. */
function drive(mod, { served = true, value = {} } = {}) {
  const seen = { formNs: undefined, slot: undefined, entry: undefined, card: undefined, watched: undefined }
  const disposers = []

  const ctx = {
    inject: (names, scope) => {
      const scoped = {
        configForms: {
          get: (ns) => {
            seen.formNs = ns
            return { value }
          },
          whileServed: (namespaces, register) => {
            seen.watched = namespaces
            // The real `whileServed` registers only while the Host serves the
            // namespace; `served` is what the Host's `settings.describe` answers.
            if (!served) return () => {}
            return register(new Set(namespaces))
          },
        },
        slots: {
          inject: (name, register) => {
            seen.slot = name
            register()
          },
          register: (options, component) => {
            seen.entry = options
            seen.card = component
            return () => {}
          },
        },
        effect: (fn) => {
          const dispose = fn()
          if (typeof dispose === 'function') disposers.push(dispose)
          return dispose
        },
      }
      scope(scoped)
    },
  }

  mod.apply(ctx)
  return { seen, disposers }
}

test('the module is the one the Plugins page loads, and asks for the slots it registers into', async () => {
  const { module: mod } = await loadClient()
  assert.equal(mod.name, 'dsh-facet')
  assert.deepEqual(mod.inject, ['slots'])
  assert.equal(typeof mod.apply, 'function')
})

test('the form binds to the profile entry id while the card registers under the package name', async () => {
  const { module: mod } = await loadClient()
  const { seen } = drive(mod)

  // These two are deliberately different strings. `facet-policy` is the `id` of
  // this bundle's row in cordis.patch.yml — what `Config` is filed under. The
  // card is dispatched by the BUNDLE's package name.
  assert.equal(seen.formNs, 'facet-policy')
  assert.equal(seen.entry.key, 'dsh-facet')
  assert.notEqual(seen.formNs, seen.entry.key, 'if these ever coincide, the trap this test guards has moved')

  assert.equal(seen.slot, 'plugins.bundle.config')
  assert.deepEqual(seen.watched, ['facet-policy'])
})

test('the host row the form binds to is the one cordis.patch.yml actually declares', async () => {
  const patch = await readFile(new URL('../cordis.patch.yml', import.meta.url), 'utf8')
  const { module: mod } = await loadClient()
  const { seen } = drive(mod)

  // A rename in the patch without a rename here is a card that writes nowhere,
  // so the id is read out of the patch rather than trusted to the test.
  assert.match(patch, new RegExp(`id:\\s*${seen.formNs}\\b`))
  assert.equal((await import('../package.json', { with: { type: 'json' } })).default.name, seen.entry.key)
})

test('nothing is registered while the Host does not serve the namespace', async () => {
  const { module: mod } = await loadClient()
  const { seen } = drive(mod, { served: false })
  assert.equal(seen.formNs, 'facet-policy', 'the form is still bound')
  assert.equal(seen.entry, undefined, 'but no card is registered for a namespace nobody serves')
})

test('the card stages exactly the fields the host marks volatile', async () => {
  const { module: mod, staged } = await loadClient()
  drive(mod)

  const declared = Object.entries(Config.dict)
    .filter(([, schema]) => schema.meta.volatile === true)
    .map(([key]) => key)

  // A field served but never staged is invisible in the UI; a field staged but
  // never served makes `whileServed` withhold the whole card.
  assert.deepEqual(
    staged.map((spec) => spec.field).sort(),
    declared.sort(),
    'the card and the host schema have drifted apart',
  )
})

test('the choice field refuses a value the schema would reject, and clears on empty', async () => {
  const { module: mod, staged } = await loadClient()
  drive(mod)
  const mode = staged.find((spec) => spec.field === 'mode')

  assert.equal(mode.parse('deny').value, 'deny')
  assert.equal(mode.parse(' DENY ').value, 'deny')
  assert.deepEqual(mode.parse(''), { kind: 'clear' })
  // Undefined marks the draft invalid, which blocks the save rather than
  // coercing a typo into a mode the Host would reject anyway.
  assert.equal(mode.parse('maybe'), undefined)
})

test('the list field clears rather than storing an empty array that shadows the default', async () => {
  const { module: mod, staged } = await loadClient()
  drive(mod)
  const roots = staged.find((spec) => spec.field === 'extraRoots')

  assert.deepEqual(roots.parse('a, b\nc').value, ['a', 'b', 'c'])
  assert.deepEqual(roots.parse('   '), { kind: 'clear' })
  assert.equal(roots.format(['a', 'b']), 'a, b')
  assert.equal(roots.format(undefined), '')
})

test('the card renders both views without reaching for anything it was not given', async () => {
  const { module: mod } = await loadClient()
  const { seen } = drive(mod)

  assert.equal(typeof seen.card, 'function')
  assert.equal(seen.card({ view: 'summary' }), 'How a call outside the session\u2019s own folder is handled, and which paths are always in scope.')

  const tree = seen.card({
    view: 'page',
    useFacetCard: (select) =>
      select({
        available: true,
        writable: true,
        dirty: false,
        invalid: false,
        saving: false,
        failed: false,
        mode: { text: 'deny', overridden: false, invalid: false },
        extraRoots: { text: 'src/shared', overridden: true, invalid: false },
      }),
    edit: () => {},
    resetField: () => {},
    save: () => {},
    discard: () => {},
  })

  // The form frame, with the segmented control reading the staged mode. Children
  // ride the `children` prop, which is how the platform's own cards pass them.
  assert.equal(tree.type, 'SettingsForm')
  const controls = tree.props.children.children
  assert.equal(controls[0].type, 'div')
  assert.equal(controls[1].type, 'SettingsValueField')
  assert.equal(controls[0].children[1].props.value, 'deny')
  assert.equal(controls[1].props.text, 'src/shared')
})