// @flow
import mkdirp from 'mkdirp';
import { appConfig } from '../../config';
import * as models from '../models';
import fs from 'fs';
import path from 'path';
import { PLUGIN_PATH } from '../common/constants';
import { resolveHomePath } from '../common/misc';
import { showError } from '../ui/components/modals/index';
import type { PluginTemplateTag } from '../templating/extensions/index';
import type { PluginTheme } from './misc';
import type { RequestGroup } from '../models/request-group';
import type { Request } from '../models/request';
import type { PluginConfig, PluginConfigMap } from '../models/settings';
import type { Workspace } from '../models/workspace';

export type Plugin = {
  name: string,
  description: string,
  version: string,
  directory: string,
  config: PluginConfig,
  module: *,
};

export type TemplateTag = {
  plugin: Plugin,
  templateTag: PluginTemplateTag,
};

export type RequestGroupAction = {
  plugin: Plugin,
  action: (
    context: Object,
    models: {
      requestGroup: RequestGroup,
      requests: Array<Request>,
    },
  ) => void | Promise<void>,
  label: string,
  icon?: string,
};

export type WorkspaceAction = {
  plugin: Plugin,
  action: (
    context: Object,
    models: {
      workspace: Workspace,
      requestGroups: Array<RequestGroup>,
      requests: Array<Request>,
    },
  ) => void | Promise<void>,
  label: string,
  icon?: string,
};

export type SpecInfo = {
  contents: Object,
  rawContents: string,
  format: string,
  formatVersion: string,
};

export type ConfigGenerator = {
  plugin: Plugin,
  generate: (info: SpecInfo) => Promise<{ document?: string, error?: string }>,
};

export type DocumentAction = {
  plugin: Plugin,
  action: (context: Object, documents: SpecInfo) => void | Promise<void>,
  label: string,
  hideAfterClick?: boolean,
};

export type RequestHook = {
  plugin: Plugin,
  hook: Function,
};

export type ResponseHook = {
  plugin: Plugin,
  hook: Function,
};

export type Theme = {
  plugin: Plugin,
  theme: PluginTheme,
};

let plugins: ?Array<Plugin> = null;

export async function init(): Promise<void> {
  await reloadPlugins();
}

async function _traversePluginPath(
  pluginMap: Object,
  allPaths: Array<string>,
  allConfigs: PluginConfigMap,
) {
  for (const p of allPaths) {
    if (!fs.existsSync(p)) {
      continue;
    }

    for (const filename of fs.readdirSync(p)) {
      try {
        const modulePath = path.join(p, filename);
        const packageJSONPath = path.join(modulePath, 'package.json');

        // Only read directories
        if (!fs.statSync(modulePath).isDirectory()) {
          continue;
        }

        // Is it a scoped directory?
        if (filename.startsWith('@')) {
          await _traversePluginPath(pluginMap, [modulePath], allConfigs);
        }

        // Is it a Node module?
        if (!fs.readdirSync(modulePath).includes('package.json')) {
          continue;
        }

        // Delete `require` cache if plugin has been required before
        for (const p of Object.keys(global.require.cache)) {
          if (p.indexOf(modulePath) === 0) {
            delete global.require.cache[p];
          }
        }

        // Use global.require() instead of require() because Webpack wraps require()
        const pluginJson = global.require(packageJSONPath);

        // Not an Insomnia plugin because it doesn't have the package.json['insomnia']
        if (!pluginJson.hasOwnProperty('insomnia')) {
          continue;
        }

        // Delete require cache entry and re-require
        const module = global.require(modulePath);

        const pluginName = pluginJson.name;

        pluginMap[pluginName] = _initPlugin(pluginJson || {}, module, allConfigs, modulePath);
        console.log(`[plugin] Loaded ${modulePath}`);
      } catch (err) {
        showError({
          title: 'Plugin Error',
          message: 'Failed to load plugin ' + filename,
          error: err,
        });
      }
    }
  }
}

export async function getPlugins(force: boolean = false): Promise<Array<Plugin>> {
  if (force) {
    plugins = null;
  }

  if (!plugins) {
    const settings = await models.settings.getOrCreate();
    const allConfigs: PluginConfigMap = settings.pluginConfig;
    const extraPaths = settings.pluginPath
      .split(':')
      .filter(p => p)
      .map(resolveHomePath);

    // Make sure the default directories exist
    mkdirp.sync(PLUGIN_PATH);

    // Also look in node_modules folder in each directory
    const basePaths = [PLUGIN_PATH, ...extraPaths];
    const extendedPaths = basePaths.map(p => path.join(p, 'node_modules'));
    const allPaths = [...basePaths, ...extendedPaths];

    // Store plugins in a map so that plugins with the same
    // name only get added once
    // TODO: Make this more complex and have the latest version always win
    const pluginMap: { [string]: Plugin } = {
      // "name": "module"
    };

    for (const p of appConfig().plugins) {
      const pluginJson = global.require(`${p}/package.json`);
      const pluginModule = global.require(p);
      pluginMap[pluginJson.name] = _initPlugin(pluginJson, pluginModule, allConfigs);
    }

    await _traversePluginPath(pluginMap, allPaths, allConfigs);

    plugins = Object.keys(pluginMap).map(name => pluginMap[name]);
  }

  return plugins;
}

export async function reloadPlugins(): Promise<void> {
  await getPlugins(true);
}

async function getActivePlugins(): Promise<Array<Plugin>> {
  return (await getPlugins()).filter(p => !p.config.disabled);
}

export async function getRequestGroupActions(): Promise<Array<RequestGroupAction>> {
  let extensions = [];
  for (const plugin of await getActivePlugins()) {
    const actions = plugin.module.requestGroupActions || [];
    extensions = [...extensions, ...actions.map(p => ({ plugin, ...p }))];
  }

  return extensions;
}

export async function getWorkspaceActions(): Promise<Array<WorkspaceAction>> {
  let extensions = [];
  for (const plugin of await getActivePlugins()) {
    const actions = plugin.module.workspaceActions || [];
    extensions = [...extensions, ...actions.map(p => ({ plugin, ...p }))];
  }

  return extensions;
}

export async function getDocumentActions(): Promise<Array<DocumentAction>> {
  let extensions = [];
  for (const plugin of await getActivePlugins()) {
    const actions = plugin.module.documentActions || [];
    extensions = [...extensions, ...actions.map(p => ({ plugin, ...p }))];
  }

  return extensions;
}

export async function getTemplateTags(): Promise<Array<TemplateTag>> {
  let extensions = [];
  for (const plugin of await getActivePlugins()) {
    const templateTags = plugin.module.templateTags || [];
    extensions = [...extensions, ...templateTags.map(tt => ({ plugin, templateTag: tt }))];
  }

  return extensions;
}

export async function getRequestHooks(): Promise<Array<RequestHook>> {
  let functions = [];
  for (const plugin of await getActivePlugins()) {
    const moreFunctions = plugin.module.requestHooks || [];
    functions = [...functions, ...moreFunctions.map(hook => ({ plugin, hook }))];
  }

  return functions;
}

export async function getResponseHooks(): Promise<Array<ResponseHook>> {
  let functions = [];
  for (const plugin of await getActivePlugins()) {
    const moreFunctions = plugin.module.responseHooks || [];
    functions = [...functions, ...moreFunctions.map(hook => ({ plugin, hook }))];
  }

  return functions;
}

export async function getThemes(): Promise<Array<Theme>> {
  let extensions = [];
  for (const plugin of await getActivePlugins()) {
    const themes = plugin.module.themes || [];
    extensions = [...extensions, ...themes.map(theme => ({ plugin, theme }))];
  }

  return extensions;
}

export async function getConfigGenerators(): Promise<Array<ConfigGenerator>> {
  let functions = [];
  for (const plugin of await getActivePlugins()) {
    const moreFunctions = plugin.module.configGenerators || [];
    functions = [...functions, ...moreFunctions.map(p => ({ plugin, ...p }))];
  }

  return functions;
}

const _defaultPluginConfig: PluginConfig = {
  disabled: false,
};

function _initPlugin(
  packageJSON: Object,
  module: any,
  allConfigs: PluginConfigMap,
  path: ?string,
): Plugin {
  const meta = packageJSON.insomnia || {};
  const name = packageJSON.name || meta.name;

  // Find config
  const config: PluginConfig = allConfigs.hasOwnProperty(name)
    ? allConfigs[name]
    : _defaultPluginConfig;

  return {
    name,
    description: packageJSON.description || meta.description || '',
    version: packageJSON.version || 'unknown',
    directory: path || '',
    config,
    module: module,
  };
}