import type {
  PluginWorkspaceFilters,
  PluginWorkspaceKey,
  PluginWorkspaceScope,
  PluginWorkspaceSource,
  PluginWorkspaceState,
} from './plugin-workspace-model';

const SCOPES: readonly PluginWorkspaceScope[] = ['all', 'project'];
const SOURCES: readonly PluginWorkspaceSource[] = ['all', 'official', 'local'];
const STATES: readonly PluginWorkspaceState[] = [
  'all', 'available', 'mine', 'enabled', 'update', 'unavailable',
];

function member<T extends string>(value: string | null, values: readonly T[]): value is T {
  return value !== null && values.includes(value as T);
}

function pluginKey(value: string | null): PluginWorkspaceKey | null {
  if (!value) return null;
  if (value.startsWith('official:') && value.length > 'official:'.length) return value as `official:${string}`;
  if (value.startsWith('local:') && value.length > 'local:'.length) return value as `local:${string}`;
  if (value.startsWith('retained:') && value.length > 'retained:'.length) return value as `retained:${string}`;
  return null;
}

export function parsePluginWorkspaceSearch(
  search: URLSearchParams,
  hasActiveProject: boolean,
): PluginWorkspaceFilters {
  const defaultScope: PluginWorkspaceScope = hasActiveProject ? 'project' : 'all';
  const requestedScope = search.get('scope');
  const requestedSource = search.get('source');
  const requestedState = search.get('state');
  const parsedScope = member(requestedScope, SCOPES) ? requestedScope : defaultScope;
  return {
    scope: parsedScope === 'project' && !hasActiveProject ? 'all' : parsedScope,
    source: member(requestedSource, SOURCES) ? requestedSource : 'all',
    state: member(requestedState, STATES) ? requestedState : 'all',
    search: search.get('q')?.trim() ?? '',
    selectedKey: pluginKey(search.get('plugin')),
  };
}

export function serializePluginWorkspaceSearch(filters: PluginWorkspaceFilters): URLSearchParams {
  const search = new URLSearchParams();
  search.set('scope', filters.scope);
  search.set('source', filters.source);
  search.set('state', filters.state);
  const query = filters.search.trim();
  if (query) search.set('q', query);
  if (filters.selectedKey) search.set('plugin', filters.selectedKey);
  return search;
}

export interface PluginWorkspaceSearchResolution {
  filters: PluginWorkspaceFilters;
  canonicalSearch: string;
  scopeFallback: boolean;
}

export function resolvePluginWorkspaceSearch(
  search: URLSearchParams,
  hasActiveProject: boolean,
): PluginWorkspaceSearchResolution {
  const filters = parsePluginWorkspaceSearch(search, hasActiveProject);
  return {
    filters,
    canonicalSearch: serializePluginWorkspaceSearch(filters).toString(),
    scopeFallback: search.get('scope') === 'project' && !hasActiveProject,
  };
}