// FROM: https://dataform.co/blog/how-we-use-mobx-to-solve-our-frontend-state
// https://assets.dataform.co/blog/archive/mobx_store.png

import {action, computed, observable, runInAction} from 'mobx';
import Loadable from './loadable';

export default class Loadable<T> {
  // our state entity class

  public static create<T>(val?: T) {
    return new Loadable<T>(val);
  }

  @observable private value: T;
  @observable private loading: boolean = false;

  constructor(val?: T) {
    this.set(val);
  }

  public isLoading() {
    return this.loading;
  }

  public val() {
    return this.value;
  }

  public set(value: T) {
    this.loading = false;
    this.value = value;
  }

  public setLoading(loading: boolean) {
    this.loading = loading;
  }
}

interface IProject {
  projectName: string;
  projectId: string;
}

export class RootStore {
  @observable public currentProjectId: string = null;
  @observable public projectsList = Loadable.create<IProject[]>();
  public readonly projectStoreMap = new Map<string, ProjectStore>();

  public projectStore(projectId: string) {
    if (!this.projectStoreMap.has(projectId)) {
      const project = this.projectsList
        .val()
        .find(project => project.projectId === projectId);
      if (!project) {
        throw new Error('Project not found');
      }
      this.projectStoreMap.set(projectId, new ProjectStore(project));
    }
    return this.projectStoreMap.get(projectId);
  }

  @computed public get currentProjectStore() {
    return this.projectStore(this.currentProjectId);
  }

  @action public setCurrentProjectId(projectId: string) {
    this.currentProjectId = projectId;
  }

  @action.bound
  public async fetchProjectsList() {
    this.projectsList.setLoading(true);
    const response = await ApiService.get().projectList({});
    runInAction('fetchProjectsListSuccess', () =>
      this.projectsList.set(response.projects)
    );
  }
}

interface IBranch {
  branchName: string;
}

class ProjectStore {
  public readonly currentProject: IProject;
  @observable public branchList = Loadable.create<IBranch[]>();
  @observable public currentBranchName: string = null;
  public readonly branchStoreMap = new Map<string, BranchStore>();

  constructor(project: IProject) {
    this.currentProject = project;
  }

  public branchStore(branchName: string) {
    if (!this.branchStoreMap.has(branchName)) {
      const branch = this.branchList
        .val()
        .find(branch => branch.branchName === branchName);
      if (!branch) {
        throw new Error('Branch not found');
      }
      this.branchStoreMap.set(branchName, new BranchStore(branch));
    }
    return this.branchStoreMap.get(branchName);
  }

  @computed public get currentBranchStore() {
    return this.branchStore(this.currentBranchName);
  }

  @action public setCurrentBranchName(branchName: string) {
    this.currentBranchName = branchName;
  }

  @action.bound
  public async fetchBranchList() {
    this.branchList.setLoading(true);
    const response = await ApiService.get().branchList({
      projectId: this.currentProject.projectId,
    });
    runInAction('fetchBranchListSuccess', () =>
      this.branchList.set(response.branches)
    );
  }
}

const rootStore = new RootStore();