/*!
 * @license
 * Copyright 2016 Alfresco Software, Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import {
    Component,
    OnInit, AfterViewChecked, OnChanges,
    SimpleChanges,
    Input,
    Output,
    EventEmitter
} from '@angular/core';
import { MATERIAL_DESIGN_DIRECTIVES } from 'ng2-alfresco-core';

import { FormService } from './../services/form.service';
import { FormModel, FormOutcomeModel, FormValues, FormFieldModel, FormOutcomeEvent } from './widgets/core/index';

import { TabsWidget } from './widgets/tabs/tabs.widget';
import { ContainerWidget } from './widgets/container/container.widget';

declare let __moduleName: string;
declare var componentHandler;

import { WidgetVisibilityService }  from './../services/widget-visibility.service';

/**
 * @Input
 * ActivitiForm can show 3 forms searching by 3 type of params:
 *   1) Form attached to a task passing the {taskId}.
 *   2) Form that are only defined with the {formId} (in this case you receive only the form definition and the form will not be
 *   attached to any process, useful in case you want to use ActivitiForm as form designer), in this case you can pass also other 2
 *   parameters:
 *      - {saveOption} as parameter to tell what is the function to call on the save action.
 *      - {data} to fill the form field with some data, the id of the form must to match the name of the field of the provided data object.
 *   3) Form that are only defined with the {formName} (in this case you receive only the form definition and the form will not be
 *   attached to any process, useful in case you want to use ActivitiForm as form designer),
 *   in this case you can pass also other 2 parameters:
 *      - {saveOption} as parameter to tell what is the function to call on the save action.
 *      - {data} to fill the form field with some data, the id of the form must to match the name of the field of the provided data object.
 *
 *   {showTitle} boolean - to hide the title of the form pass false, default true;
 *
 *   {showRefreshButton} boolean - to hide the refresh button of the form pass false, default true;
 *
 *   {showCompleteButton} boolean - to hide the complete button of the form pass false, default true;
 *
 *   {showSaveButton} boolean - to hide the save button of the form pass false, default true;
 *
 *   @Output
 *   {formLoaded} EventEmitter - This event is fired when the form is loaded, it pass all the value in the form.
 *   {formSaved} EventEmitter - This event is fired when the form is saved, it pass all the value in the form.
 *   {formCompleted} EventEmitter - This event is fired when the form is completed, it pass all the value in the form.
 *
 * @returns {ActivitiForm} .
 */
@Component({
    moduleId: __moduleName,
    selector: 'activiti-form',
    templateUrl: './activiti-form.component.html',
    styleUrls: ['./activiti-form.component.css'],
    directives: [MATERIAL_DESIGN_DIRECTIVES, ContainerWidget, TabsWidget],
    providers: [FormService, WidgetVisibilityService]
})
export class ActivitiForm implements OnInit, AfterViewChecked, OnChanges {

    static SAVE_OUTCOME_ID: string = '$save';
    static COMPLETE_OUTCOME_ID: string = '$complete';
    static CUSTOM_OUTCOME_ID: string = '$custom';

    @Input()
    taskId: string;

    @Input()
    formId: string;

    @Input()
    formName: string;

    @Input()
    data: FormValues;

    @Input()
    showTitle: boolean = true;

    @Input()
    showCompleteButton: boolean = true;

    @Input()
    showSaveButton: boolean = true;

    @Input()
    readOnly: boolean = false;

    @Input()
    showRefreshButton: boolean = true;

    @Output()
    formSaved: EventEmitter<FormModel> = new EventEmitter<FormModel>();

    @Output()
    formCompleted: EventEmitter<FormModel> = new EventEmitter<FormModel>();

    @Output()
    formLoaded: EventEmitter<FormModel> = new EventEmitter<FormModel>();

    @Output()
    executeOutcome: EventEmitter<FormOutcomeEvent> = new EventEmitter<FormOutcomeEvent>();

    form: FormModel;

    debugMode: boolean = false;

    constructor(private formService: FormService,
                private visibilityService: WidgetVisibilityService) {
    }

    hasForm(): boolean {
        return this.form ? true : false;
    }

    isTitleEnabled(): boolean {
        if (this.showTitle) {
            if (this.form && this.form.taskName) {
                return true;
            }
        }
        return false;
    }

    isOutcomeButtonEnabled(outcome: FormOutcomeModel): boolean {
        if (outcome && outcome.name) {
            if (outcome.name === FormOutcomeModel.COMPLETE_ACTION) {
                return this.showCompleteButton;
            }
            if (outcome.name === FormOutcomeModel.SAVE_ACTION) {
                return this.showSaveButton;
            }
            return true;
        }
        return false;
    }

    ngOnInit() {
        this.loadForm();
    }

    ngAfterViewChecked() {
        this.setupMaterialComponents();
    }

    ngOnChanges(changes: SimpleChanges) {
        let taskId = changes['taskId'];
        if (taskId && taskId.currentValue) {
            this.getFormByTaskId(taskId.currentValue);
            return;
        }

        let formId = changes['formId'];
        if (formId && formId.currentValue) {
            this.getFormDefinitionByFormId(formId.currentValue);
            return;
        }

        let formName = changes['formName'];
        if (formName && formName.currentValue) {
            this.getFormDefinitionByFormName(formName.currentValue);
            return;
        }
    }

    /**
     * Invoked when user clicks outcome button.
     * @param outcome Form outcome model
     * @returns {boolean} True if outcome action was executed, otherwise false.
     */
    onOutcomeClicked(outcome: FormOutcomeModel): boolean {
        if (!this.readOnly && outcome && this.form) {

            let args = new FormOutcomeEvent(outcome);
            this.executeOutcome.emit(args);
            if (args.defaultPrevented) {
                return false;
            }

            if (outcome.isSystem) {
                if (outcome.id === ActivitiForm.SAVE_OUTCOME_ID) {
                    this.saveTaskForm();
                    return true;
                }

                if (outcome.id === ActivitiForm.COMPLETE_OUTCOME_ID) {
                    this.completeTaskForm();
                    return true;
                }

                if (outcome.id === ActivitiForm.CUSTOM_OUTCOME_ID) {
                    this.formSaved.emit(this.form);
                    return true;
                }
            } else {
                // Note: Activiti is using NAME field rather than ID for outcomes
                if (outcome.name) {
                    this.formSaved.emit(this.form);
                    this.completeTaskForm(outcome.name);
                    return true;
                }
            }
        }

        return false;
    }

    /**
     * Invoked when user clicks form refresh button.
     */
    onRefreshClicked() {
        this.loadForm();
    }

    loadForm() {
        if (this.taskId) {
            this.getFormByTaskId(this.taskId);
            this.visibilityService.getTaskProcessVariableModelsForTask(this.taskId);
            return;
        }

        if (this.formId) {
            this.getFormDefinitionByFormId(this.formId);
            return;
        }

        if (this.formName) {
            this.getFormDefinitionByFormName(this.formName);
            return;
        }
    }

    setupMaterialComponents(): boolean {
        // workaround for MDL issues with dynamic components
        if (componentHandler) {
            componentHandler.upgradeAllRegistered();
            return true;
        }
        return false;
    }

    getFormByTaskId(taskId: string) {
        let data = this.data;
        this.formService
            .getTaskForm(taskId)
            .subscribe(
                form => {
                    this.form = new FormModel(form, data, this.readOnly);
                    this.formLoaded.emit(this.form);
                },
                this.handleError
            );
    }

    getFormDefinitionByFormId(formId: string) {
        this.formService
            .getFormDefinitionById(formId)
            .subscribe(
                form => {
                    // console.log('Get Form By definition Id', form);
                    this.form = this.parseForm(form);
                    this.formLoaded.emit(this.form);
                },
                this.handleError
            );
    }

    getFormDefinitionByFormName(formName: string) {
        this.formService
            .getFormDefinitionByName(formName)
            .subscribe(
                id => {
                    this.formService.getFormDefinitionById(id).subscribe(
                        form => {
                            // console.log('Get Form By Form definition Name', form);
                            this.form = this.parseForm(form);
                            this.formLoaded.emit(this.form);
                        },
                        this.handleError
                    );
                },
                this.handleError
            );
    }

    saveTaskForm() {
        if (this.form && this.form.taskId) {
            this.formService
                .saveTaskForm(this.form.taskId, this.form.values)
                .subscribe(
                    () => this.formSaved.emit(this.form),
                    this.handleError
                );
        }
    }

    completeTaskForm(outcome?: string) {
        if (this.form && this.form.taskId) {
            this.formService
                .completeTaskForm(this.form.taskId, this.form.values, outcome)
                .subscribe(
                    () => this.formCompleted.emit(this.form),
                    this.handleError
                );
        }
    }

    handleError(err: any) {
        console.log(err);
    }

    parseForm(json: any): FormModel {
        if (json) {
            let form = new FormModel(json, this.data, this.readOnly);
            if (!json.fields) {
                form.outcomes = this.getFormDefinitionOutcomes(form);
            }
            return form;
        }
        return null;
    }

    /**
     * Get custom set of outcomes for a Form Definition.
     * @param form Form definition model.
     * @returns {FormOutcomeModel[]} Outcomes for a given form definition.
     */
    getFormDefinitionOutcomes(form: FormModel): FormOutcomeModel[] {
        return [
            new FormOutcomeModel(form, { id: '$custom', name: FormOutcomeModel.SAVE_ACTION, isSystem: true })
        ];
    }

    checkVisibility(field: FormFieldModel) {
        if (field && field.form) {
            this.visibilityService.updateVisibilityForForm(field.form);
        }
    }
}