import type { LocationQuery } from 'vue-router';

const DEFAULT_PLUGIN_PAGE_NUMBER = 1;
const DEFAULT_PLUGIN_PAGE_SIZE = 12;
const DEFAULT_PLUGIN_CATEGORY_ID = '0';
const PLUGIN_PAGE_SIZES = new Set([12, 24, 36, 48]);

const DEFAULT_TOOL_PAGE_NUMBER = 1;
const DEFAULT_TOOL_PAGE_SIZE = 10;
const TOOL_PAGE_SIZES = new Set([10, 20, 50, 100]);

const PLUGIN_LIST_QUERY_KEYS = {
  categoryId: 'categoryId',
  keyword: 'keyword',
  pageNumber: 'pageNumber',
  pageSize: 'pageSize',
} as const;

const PLUGIN_RETURN_QUERY_KEYS = {
  categoryId: 'returnCategoryId',
  keyword: 'returnKeyword',
  pageNumber: 'returnPageNumber',
  pageSize: 'returnPageSize',
} as const;

const TOOL_LIST_QUERY_KEYS = {
  keyword: 'toolKeyword',
  pageNumber: 'toolPageNumber',
  pageSize: 'toolPageSize',
} as const;

interface PluginListRouteState {
  categoryId: string;
  keyword: string;
  pageNumber: number;
  pageSize: number;
}

interface PluginToolListRouteState {
  keyword: string;
  pageNumber: number;
  pageSize: number;
}

function readQueryValue(query: LocationQuery, key: string): string {
  const value = query[key];
  const normalized = Array.isArray(value) ? value[0] : value;
  return normalized === null || normalized === undefined
    ? ''
    : String(normalized);
}

function parsePositiveInteger(value: string, fallback: number): number {
  if (!/^\d+$/.test(value)) {
    return fallback;
  }
  const parsed = Number(value);
  return Number.isSafeInteger(parsed) && parsed > 0 ? parsed : fallback;
}

function parsePluginState(
  query: LocationQuery,
  keys: typeof PLUGIN_LIST_QUERY_KEYS | typeof PLUGIN_RETURN_QUERY_KEYS,
): PluginListRouteState {
  const pageSize = parsePositiveInteger(
    readQueryValue(query, keys.pageSize),
    DEFAULT_PLUGIN_PAGE_SIZE,
  );
  return {
    categoryId:
      readQueryValue(query, keys.categoryId) || DEFAULT_PLUGIN_CATEGORY_ID,
    keyword: readQueryValue(query, keys.keyword),
    pageNumber: parsePositiveInteger(
      readQueryValue(query, keys.pageNumber),
      DEFAULT_PLUGIN_PAGE_NUMBER,
    ),
    pageSize: PLUGIN_PAGE_SIZES.has(pageSize)
      ? pageSize
      : DEFAULT_PLUGIN_PAGE_SIZE,
  };
}

function buildPluginStateQuery(
  state: PluginListRouteState,
  keys: typeof PLUGIN_LIST_QUERY_KEYS | typeof PLUGIN_RETURN_QUERY_KEYS,
): LocationQuery {
  return {
    ...(state.pageNumber === DEFAULT_PLUGIN_PAGE_NUMBER
      ? {}
      : { [keys.pageNumber]: String(state.pageNumber) }),
    ...(state.pageSize === DEFAULT_PLUGIN_PAGE_SIZE
      ? {}
      : { [keys.pageSize]: String(state.pageSize) }),
    ...(state.categoryId === DEFAULT_PLUGIN_CATEGORY_ID
      ? {}
      : { [keys.categoryId]: state.categoryId }),
    ...(state.keyword ? { [keys.keyword]: state.keyword } : {}),
  };
}

function parsePluginListRouteState(query: LocationQuery): PluginListRouteState {
  return parsePluginState(query, PLUGIN_LIST_QUERY_KEYS);
}

function parsePluginToolsReturnState(
  query: LocationQuery,
): PluginListRouteState {
  return parsePluginState(query, PLUGIN_RETURN_QUERY_KEYS);
}

function buildPluginListRouteQuery(state: PluginListRouteState): LocationQuery {
  return buildPluginStateQuery(state, PLUGIN_LIST_QUERY_KEYS);
}

function buildPluginToolsReturnQuery(
  state: PluginListRouteState,
): LocationQuery {
  return buildPluginStateQuery(state, PLUGIN_RETURN_QUERY_KEYS);
}

function mergePluginListRouteQuery(
  query: LocationQuery,
  state: PluginListRouteState,
): LocationQuery {
  const listKeys = new Set<string>(Object.values(PLUGIN_LIST_QUERY_KEYS));
  return {
    ...Object.fromEntries(
      Object.entries(query).filter(([key]) => !listKeys.has(key)),
    ),
    ...buildPluginListRouteQuery(state),
  };
}

function parsePluginToolListRouteState(
  query: LocationQuery,
): PluginToolListRouteState {
  const pageSize = parsePositiveInteger(
    readQueryValue(query, TOOL_LIST_QUERY_KEYS.pageSize),
    DEFAULT_TOOL_PAGE_SIZE,
  );
  return {
    keyword: readQueryValue(query, TOOL_LIST_QUERY_KEYS.keyword),
    pageNumber: parsePositiveInteger(
      readQueryValue(query, TOOL_LIST_QUERY_KEYS.pageNumber),
      DEFAULT_TOOL_PAGE_NUMBER,
    ),
    pageSize: TOOL_PAGE_SIZES.has(pageSize) ? pageSize : DEFAULT_TOOL_PAGE_SIZE,
  };
}

function buildPluginToolListRouteQuery(
  state: PluginToolListRouteState,
): LocationQuery {
  return {
    ...(state.pageNumber === DEFAULT_TOOL_PAGE_NUMBER
      ? {}
      : { [TOOL_LIST_QUERY_KEYS.pageNumber]: String(state.pageNumber) }),
    ...(state.pageSize === DEFAULT_TOOL_PAGE_SIZE
      ? {}
      : { [TOOL_LIST_QUERY_KEYS.pageSize]: String(state.pageSize) }),
    ...(state.keyword ? { [TOOL_LIST_QUERY_KEYS.keyword]: state.keyword } : {}),
  };
}

function mergePluginToolListRouteQuery(
  query: LocationQuery,
  state: PluginToolListRouteState,
): LocationQuery {
  const listKeys = new Set<string>(Object.values(TOOL_LIST_QUERY_KEYS));
  return {
    ...Object.fromEntries(
      Object.entries(query).filter(([key]) => !listKeys.has(key)),
    ),
    ...buildPluginToolListRouteQuery(state),
  };
}

function buildPluginToolsRouteQueryFromEdit(
  query: LocationQuery,
  pluginId: string,
): LocationQuery {
  const nextQuery: LocationQuery = { ...query, id: pluginId };
  delete nextQuery.pluginId;
  return nextQuery;
}

export {
  buildPluginListRouteQuery,
  buildPluginToolsReturnQuery,
  buildPluginToolsRouteQueryFromEdit,
  mergePluginListRouteQuery,
  mergePluginToolListRouteQuery,
  parsePluginListRouteState,
  parsePluginToolListRouteState,
  parsePluginToolsReturnState,
};
export type { PluginListRouteState, PluginToolListRouteState };