import angular from "angular";
import _ from "lodash";

import config from "app/core/config";
import coreModule from "app/core/core_module";
import { importPluginModule } from "./plugin_loader";

import { UnknownPanelCtrl } from "app/plugins/panel/unknown/module";
import { DashboardRowCtrl } from "./row_ctrl";

/** @ngInject **/
function pluginDirectiveLoader(
  $compile,
  datasourceSrv,
  $rootScope,
  $q,
  $http,
  $templateCache
) {
  function getTemplate(component) {
    if (component.template) {
      return $q.when(component.template);
    }
    var cached = $templateCache.get(component.templateUrl);
    if (cached) {
      return $q.when(cached);
    }
    return $http.get(component.templateUrl).then(res => {
      return res.data;
    });
  }

  function relativeTemplateUrlToAbs(templateUrl, baseUrl) {
    if (!templateUrl) {
      return undefined;
    }
    if (templateUrl.indexOf("public") === 0) {
      return templateUrl;
    }
    return baseUrl + "/" + templateUrl;
  }

  function getPluginComponentDirective(options) {
    // handle relative template urls for plugin templates
    options.Component.templateUrl = relativeTemplateUrlToAbs(
      options.Component.templateUrl,
      options.baseUrl
    );

    return function() {
      return {
        templateUrl: options.Component.templateUrl,
        template: options.Component.template,
        restrict: "E",
        controller: options.Component,
        controllerAs: "ctrl",
        bindToController: true,
        scope: options.bindings,
        link: (scope, elem, attrs, ctrl) => {
          if (ctrl.link) {
            ctrl.link(scope, elem, attrs, ctrl);
          }
          if (ctrl.init) {
            ctrl.init();
          }
        }
      };
    };
  }

  function loadPanelComponentInfo(scope, attrs) {
    if (scope.panel.type === "row") {
      return $q.when({
        name: "dashboard-row",
        bindings: { dashboard: "=", panel: "=" },
        attrs: { dashboard: "ctrl.dashboard", panel: "panel" },
        Component: DashboardRowCtrl
      });
    }

    var componentInfo: any = {
      name: "panel-plugin-" + scope.panel.type,
      bindings: { dashboard: "=", panel: "=", row: "=" },
      attrs: {
        dashboard: "dashboard",
        panel: "panel",
        class: "panel-height-helper"
      }
    };

    let panelInfo = config.panels[scope.panel.type];
    var panelCtrlPromise = Promise.resolve(UnknownPanelCtrl);
    if (panelInfo) {
      panelCtrlPromise = importPluginModule(panelInfo.module).then(function(
        panelModule
      ) {
        return panelModule.PanelCtrl;
      });
    }

    return panelCtrlPromise.then(function(PanelCtrl: any) {
      componentInfo.Component = PanelCtrl;

      if (!PanelCtrl || PanelCtrl.registered) {
        return componentInfo;
      }

      if (PanelCtrl.templatePromise) {
        return PanelCtrl.templatePromise.then(res => {
          return componentInfo;
        });
      }

      if (panelInfo) {
        PanelCtrl.templateUrl = relativeTemplateUrlToAbs(
          PanelCtrl.templateUrl,
          panelInfo.baseUrl
        );
      }

      PanelCtrl.templatePromise = getTemplate(PanelCtrl).then(template => {
        PanelCtrl.templateUrl = null;
        PanelCtrl.template = `<grafana-panel ctrl="ctrl" class="panel-height-helper">${template}</grafana-panel>`;
        return componentInfo;
      });

      return PanelCtrl.templatePromise;
    });
  }

  function getModule(scope, attrs) {
    switch (attrs.type) {
      // QueryCtrl
      case "query-ctrl": {
        let datasource = scope.target.datasource || scope.ctrl.panel.datasource;
        return datasourceSrv.get(datasource).then(ds => {
          scope.datasource = ds;

          return importPluginModule(ds.meta.module).then(dsModule => {
            return {
              baseUrl: ds.meta.baseUrl,
              name: "query-ctrl-" + ds.meta.id,
              bindings: { target: "=", panelCtrl: "=", datasource: "=" },
              attrs: {
                target: "target",
                "panel-ctrl": "ctrl.panelCtrl",
                datasource: "datasource"
              },
              Component: dsModule.QueryCtrl
            };
          });
        });
      }
      // QueryOptionsCtrl
      case "query-options-ctrl": {
        return datasourceSrv.get(scope.ctrl.panel.datasource).then(ds => {
          return importPluginModule(ds.meta.module).then((dsModule): any => {
            if (!dsModule.QueryOptionsCtrl) {
              return { notFound: true };
            }

            return {
              baseUrl: ds.meta.baseUrl,
              name: "query-options-ctrl-" + ds.meta.id,
              bindings: { panelCtrl: "=" },
              attrs: { "panel-ctrl": "ctrl.panelCtrl" },
              Component: dsModule.QueryOptionsCtrl
            };
          });
        });
      }
      // Annotations
      case "annotations-query-ctrl": {
        return importPluginModule(
          scope.ctrl.currentDatasource.meta.module
        ).then(function(dsModule) {
          return {
            baseUrl: scope.ctrl.currentDatasource.meta.baseUrl,
            name:
              "annotations-query-ctrl-" + scope.ctrl.currentDatasource.meta.id,
            bindings: { annotation: "=", datasource: "=" },
            attrs: {
              annotation: "ctrl.currentAnnotation",
              datasource: "ctrl.currentDatasource"
            },
            Component: dsModule.AnnotationsQueryCtrl
          };
        });
      }
      // Datasource ConfigCtrl
      case "datasource-config-ctrl": {
        var dsMeta = scope.ctrl.datasourceMeta;
        return importPluginModule(dsMeta.module).then(function(dsModule): any {
          if (!dsModule.ConfigCtrl) {
            return { notFound: true };
          }

          return {
            baseUrl: dsMeta.baseUrl,
            name: "ds-config-" + dsMeta.id,
            bindings: { meta: "=", current: "=" },
            attrs: { meta: "ctrl.datasourceMeta", current: "ctrl.current" },
            Component: dsModule.ConfigCtrl
          };
        });
      }
      // AppConfigCtrl
      case "app-config-ctrl": {
        let model = scope.ctrl.model;
        return importPluginModule(model.module).then(function(appModule) {
          return {
            baseUrl: model.baseUrl,
            name: "app-config-" + model.id,
            bindings: { appModel: "=", appEditCtrl: "=" },
            attrs: { "app-model": "ctrl.model", "app-edit-ctrl": "ctrl" },
            Component: appModule.ConfigCtrl
          };
        });
      }
      // App Page
      case "app-page": {
        let appModel = scope.ctrl.appModel;
        return importPluginModule(appModel.module).then(function(appModule) {
          return {
            baseUrl: appModel.baseUrl,
            name: "app-page-" + appModel.id + "-" + scope.ctrl.page.slug,
            bindings: { appModel: "=" },
            attrs: { "app-model": "ctrl.appModel" },
            Component: appModule[scope.ctrl.page.component]
          };
        });
      }
      // Panel
      case "panel": {
        return loadPanelComponentInfo(scope, attrs);
      }
      default: {
        return $q.reject({
          message: "Could not find component type: " + attrs.type
        });
      }
    }
  }

  function appendAndCompile(scope, elem, componentInfo) {
    var child = angular.element(document.createElement(componentInfo.name));
    _.each(componentInfo.attrs, (value, key) => {
      child.attr(key, value);
    });

    $compile(child)(scope);
    elem.empty();

    // let a binding digest cycle complete before adding to dom
    setTimeout(function() {
      elem.append(child);
      scope.$applyAsync(function() {
        scope.$broadcast("component-did-mount");
        scope.$broadcast("refresh");
      });
    });
  }

  function registerPluginComponent(scope, elem, attrs, componentInfo) {
    if (componentInfo.notFound) {
      elem.empty();
      return;
    }

    if (!componentInfo.Component) {
      throw {
        message:
          "Failed to find exported plugin component for " + componentInfo.name
      };
    }

    if (!componentInfo.Component.registered) {
      var directiveName = attrs.$normalize(componentInfo.name);
      var directiveFn = getPluginComponentDirective(componentInfo);
      coreModule.directive(directiveName, directiveFn);
      componentInfo.Component.registered = true;
    }

    appendAndCompile(scope, elem, componentInfo);
  }

  return {
    restrict: "E",
    link: function(scope, elem, attrs) {
      getModule(scope, attrs)
        .then(function(componentInfo) {
          registerPluginComponent(scope, elem, attrs, componentInfo);
        })
        .catch(err => {
          $rootScope.appEvent("alert-error", [
            "Plugin Error",
            err.message || err
          ]);
          console.log("Plugin component error", err);
        });
    }
  };
}

coreModule.directive("pluginComponent", pluginDirectiveLoader);