/**
 * Client-side read of the user-facing "Side card" preferences. The host owns
 * the namespace through the settings seam (in-process); the DSH settings RPC
 * domain only serves allowlisted namespaces to configuration clients, so the
 * client reads and writes THIS namespace through the plugin's own fenced
 * /sidebar routes instead (api.settingsGet/settingsUpdate). Any failure
 * (route rejected, namespace absent, a field of the wrong type, a value out
 * of the contract range) falls back to the schema defaults — the side card
 * must keep working exactly as composed when the settings surface is missing.
 */
import type { api } from './api.ts'
import {
  clampWidthPercent,
  SIDEBAR_PREFS_DEFAULTS,
  type SidebarPrefs,
} from '../prefs-shared.ts'

export { SIDEBAR_PREFS_DEFAULTS, clampWidthPercent }
export type { SidebarPrefs }

/** The settings wire face the preferences need (a subset of the plugin api). */
export type SidebarSettingsClient = Pick<typeof api, 'settingsGet' | 'settingsUpdate'>

/**
 * Validate one raw resolved value into {@link SidebarPrefs}. Used for the
 * settings.get payload AND the settings.update response (both carry the
 * layered resolved value); any malformed field falls back to its default.
 * @param value - the raw resolved section from the settings wire.
 * @returns validated prefs (always well-formed).
 */
export function parsePrefs(value: unknown): SidebarPrefs {
  if (value === null || typeof value !== 'object') return { ...SIDEBAR_PREFS_DEFAULTS }
  const record = value as Record<string, unknown>
  return {
    openByDefault: typeof record.openByDefault === 'boolean'
      ? record.openByDefault
      : SIDEBAR_PREFS_DEFAULTS.openByDefault,
    defaultWidthPercent: typeof record.defaultWidthPercent === 'number' && Number.isFinite(record.defaultWidthPercent)
      ? clampWidthPercent(record.defaultWidthPercent)
      : SIDEBAR_PREFS_DEFAULTS.defaultWidthPercent,
    autoOpenSubagent: typeof record.autoOpenSubagent === 'boolean'
      ? record.autoOpenSubagent
      : SIDEBAR_PREFS_DEFAULTS.autoOpenSubagent,
    agentTerminalTools: typeof record.agentTerminalTools === 'boolean'
      ? record.agentTerminalTools
      : SIDEBAR_PREFS_DEFAULTS.agentTerminalTools,
  }
}

/**
 * Read the resolved side card preferences through the plugin's settings route.
 * @param settings - the settings wire face (the plugin api by default).
 * @returns validated prefs, or the schema defaults when the route rejects,
 * the namespace is absent, or a stored value violates the contract.
 */
export async function loadPrefs(settings: SidebarSettingsClient): Promise<SidebarPrefs> {
  try {
    const view = await settings.settingsGet()
    return parsePrefs(view.value)
  } catch {
    // Transport/fence rejection or a malformed response: keep the defaults.
    return { ...SIDEBAR_PREFS_DEFAULTS }
  }
}