"use strict";

XPCOMUtils.defineLazyModuleGetter(this, "ExtensionPermissions",
                                  "resource://gre/modules/ExtensionPermissions.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "Services",
                                  "resource://gre/modules/Services.jsm");

var {
  ExtensionError,
} = ExtensionUtils;

XPCOMUtils.defineLazyPreferenceGetter(this, "promptsEnabled",
                                      "extensions.webextOptionalPermissionPrompts");

this.permissions = class extends ExtensionAPI {
  getAPI(context) {
    return {
      permissions: {
        async request(perms) {
          let {permissions, origins} = perms;

          let manifestPermissions = context.extension.manifest.optional_permissions;
          for (let perm of permissions) {
            if (!manifestPermissions.includes(perm)) {
              throw new ExtensionError(`Cannot request permission ${perm} since it was not declared in optional_permissions`);
            }
          }

          let optionalOrigins = context.extension.optionalOrigins;
          for (let origin of origins) {
            if (!optionalOrigins.subsumes(new MatchPattern(origin))) {
              throw new ExtensionError(`Cannot request origin permission for ${origin} since it was not declared in optional_permissions`);
            }
          }

          if (promptsEnabled) {
            permissions = permissions.filter(perm => !context.extension.hasPermission(perm));
            origins = origins.filter(origin => !context.extension.whiteListedHosts.subsumes(new MatchPattern(origin)));

            if (permissions.length == 0 && origins.length == 0) {
              return true;
            }

            let browser = context.pendingEventBrowser || context.xulBrowser;
            let allow = await new Promise(resolve => {
              let subject = {
                wrappedJSObject: {
                  browser,
                  name: context.extension.name,
                  icon: context.extension.iconURL,
                  permissions: {permissions, origins},
                  resolve,
                },
              };
              Services.obs.notifyObservers(subject, "webextension-optional-permission-prompt");
            });
            if (!allow) {
              return false;
            }
          }

          await ExtensionPermissions.add(context.extension, perms);
          return true;
        },

        async getAll() {
          let perms = context.extension.userPermissions;
          delete perms.apis;
          return perms;
        },

        async contains(permissions) {
          for (let perm of permissions.permissions) {
            if (!context.extension.hasPermission(perm)) {
              return false;
            }
          }

          for (let origin of permissions.origins) {
            if (!context.extension.whiteListedHosts.subsumes(new MatchPattern(origin))) {
              return false;
            }
          }

          return true;
        },

        async remove(permissions) {
          await ExtensionPermissions.remove(context.extension, permissions);
          return true;
        },
      },
    };
  }
};

/* eslint-disable mozilla/balanced-listeners */
extensions.on("uninstall", extension => {
  ExtensionPermissions.removeAll(extension);
});