<template>
  <div>
    <h1>Tasks</h1>

    <app-dropdown button-class="is-primary" :open="showListDropdown" :label="listSelectLabel" @open="showListDropdown = true" @close="showListDropdown = false">

      <task-list-dropdown-item v-for="l in taskLists" :task-list="l" :active="currentList !== null && currentList.id === l.id" @select="selectList" @delete="deleteList"></task-list-dropdown-item>

      <hr class="dropdown-divider" v-if="taskLists.length > 0">
      <div class="dropdown-item">
        <task-list-mini-form :task-list="newList" :validation-errors="newListValidationErrors" @save="saveNewList"></task-list-mini-form>
      </div>
    </app-dropdown>

    <div v-if="currentList !== null">

      <task-item-list :task-items="currentList.task_items"></task-item-list>

    </div>

  </div>
</template>

<script>

  import api from "../lib/Api";
  import * as Errors from '../lib/Errors';
  import TaskListMiniForm from "./TaskListMiniForm";
  import TaskListDropdownItem from "./TaskListDropdownItem";
  import TaskItemList from "./TaskItemList";

  const newListTemplate = function() {
    return {
      name: ''
    };
  };

  export default {
    data() {
      return {
        taskLists: [],
        showListDropdown: false,
        currentList: null,
        newList: newListTemplate(),
        newListValidationErrors: {}
      }
    },

    computed: {
      listSelectLabel() {
        if (this.currentList === null) {
          return "Select or Create a List";
        } else {
          return this.currentList.name;
        }
      }
    },

    methods: {
      selectList(list) {
        this.currentList = list;
        this.showListDropdown = false;
      },

      saveNewList() {
        this.loadResource(
          api.postTaskList(this.newList)
            .then(l => this.currentList = l)
            .then(() => this.showListDropdown = false)
            .then(() => this.updateData())
            .then(() => { this.newList = newListTemplate(); this.newListValidationErrors = {}; } )
            .catch(Errors.onlyFor(Errors.ApiValidationError, err => this.newListValidationErrors = err.validationErrors()))
        );
      },

      updateData() {
        return this.loadResource(api.getTaskLists(data => this.setNewData(data)));
      },

      setNewData(list) {
        this.taskLists = list;
        if (this.currentList !== null) {
          this.currentList = this.taskLists.find(l => this.currentList.id === l.id) || null;
        }

        if (this.currentList === null && this.taskLists.length > 0) {
          this.currentList = this.taskLists[0];
        }
      },

      deleteList(list) {
        this.loadResource(
          api.deleteTaskList(list)
            .then(() => this.updateData())
        );
      }
    },

    created() {
      this.updateData()
    },

    components: {
      TaskListMiniForm,
      TaskListDropdownItem,
      TaskItemList
    }
  }

</script>

<style lang="scss" scoped>

</style>