/**
 * FileExplorer.js
 *
 * @author realor
 */

import { Panel } from './Panel.js'
import { Controls } from './Controls.js'
import { Dialog } from './Dialog.js'
import { LoginDialog } from './LoginDialog.js'
import { ServiceDialog } from './ServiceDialog.js'
import { MessageDialog } from './MessageDialog.js'
import { ConfirmDialog } from './ConfirmDialog.js'
import { Toast } from './Toast.js'
import { ServiceManager } from '../io/ServiceManager.js'
import { FileService, Metadata, Result } from '../io/FileService.js'
import { I18N } from '../i18n/I18N.js'

class FileExplorer extends Panel {
    constructor(application, createContextButtons = true) {
        super(application)
        this.id = 'file_explorer'
        this.title = 'title.file_explorer'
        this.position = 'left'
        this.group = 'model' // service group
        this.minimumHeight = 200

        this.service = null // current service
        this.basePath = '/'
        this.entryName = ''
        this.entryType = null // COLLECTION or FILE
        this.showFileSize = true

        this.serviceElem = document.createElement('div')
        this.serviceElem.className = 'service_panel'

        this.headerElem = document.createElement('div')
        this.headerElem.className = 'header'

        this.homeButtonElem = Controls.addImageButton(this.headerElem, 'home', 'button.home', event => this.goHome(), 'image_button home')

        this.backButtonElem = Controls.addImageButton(this.headerElem, 'home', 'button.back', event => this.goBack(), 'image_button back')

        this.directoryElem = document.createElement('div')
        this.directoryElem.className = 'directory'

        this.entriesElem = document.createElement('ul')
        this.entriesElem.className = 'path_entries'

        this.footerElem = document.createElement('div')
        this.footerElem.className = 'footer'

        this.buttonsPanelElem = document.createElement('div')
        this.buttonsPanelElem.className = 'buttons_panel'

        this.bodyElem.appendChild(this.serviceElem)

        this.serviceElem.appendChild(this.headerElem)
        this.serviceElem.appendChild(this.entriesElem)
        this.serviceElem.appendChild(this.footerElem)

        this.headerElem.appendChild(this.homeButtonElem)
        this.headerElem.appendChild(this.backButtonElem)
        this.headerElem.appendChild(this.directoryElem)

        this.footerElem.appendChild(this.buttonsPanelElem)
        this.showButtonsPanel()

        if (createContextButtons) {
            this.addContextButtons()
        }
    }

    addContextButton(name, label, action, isVisible) {
        const buttonElem = Controls.addButton(this.buttonsPanelElem, name, label, action)
        buttonElem._isVisible = isVisible
    }

    addContextButtons() {
        this.addContextButton(
            'open',
            'button.open',
            () => this.openEntry(),
            () => this.isEntrySelected()
        )

        this.addCommonContextButtons()
        this.addServiceContextButtons()
    }

    addCommonContextButtons() {
        this.addContextButton(
            'delete',
            'button.delete',
            () => this.showDeleteDialog(),
            () => this.isEntrySelected()
        )

        this.addContextButton(
            'folder',
            'button.folder',
            () => this.showFolderDialog(),
            () => this.isDirectoryList()
        )

        this.addContextButton(
            'upload',
            'button.upload',
            () => this.showUploadDialog(),
            () => this.isDirectoryList()
        )

        this.addContextButton(
            'download',
            'button.download',
            () => this.download(this.basePath + '/' + this.entryName),
            () => this.isDirectoryList() && this.isFileEntrySelected()
        )
    }

    addServiceContextButtons() {
        this.addContextButton(
            'add',
            'button.add',
            () => this.showAddDialog(),
            () => this.isServiceList()
        )

        this.addContextButton(
            'edit',
            'button.edit',
            () => this.showEditDialog(),
            () => this.isServiceList() && this.isEntrySelected()
        )
    }

    isServiceList() {
        return this.service === null
    }

    isDirectoryList() {
        return this.service !== null
    }

    isEntrySelected() {
        return this.entryName !== ''
    }

    isFileEntrySelected() {
        return this.entryType === Metadata.FILE
    }

    isCollectionEntrySelected() {
        return this.entryType === Metadata.COLLECTION
    }

    showAddDialog() {
        const serviceTypes = ServiceManager.getTypesOf(FileService)
        let dialog = new ServiceDialog('title.add_cloud_service', serviceTypes)
        dialog.setI18N(this.application.i18n)
        dialog.onSave = (serviceType, name, description, url, username, password) => {
            const service = new ServiceManager.classes[serviceType]()
            service.name = name
            service.description = description
            service.url = url
            service.username = username
            service.password = password
            this.application.addService(service, this.group)
            this.showServices()
        }
        dialog.show()
    }

    showEditDialog() {
        const service = this.application.services[this.group][this.entryName]

        const serviceTypes = ServiceManager.getTypesOf(FileService)
        let dialog = new ServiceDialog('title.edit_cloud_service', serviceTypes, service.constructor.type, service.name, service.description, service.url, service.username, service.password)
        dialog.setI18N(this.application.i18n)
        dialog.serviceTypeSelect.disabled = true
        dialog.nameElem.readOnly = true
        dialog.onSave = (serviceType, name, description, url, username, password) => {
            service.description = description
            service.url = url
            service.username = username
            service.password = password
            this.application.addService(service, this.group)
            this.showServices()
        }
        dialog.show()
    }

    showDeleteDialog() {
        const application = this.application
        let name = this.entryName
        if (this.service === null) {
            ConfirmDialog.create('title.delete_cloud_service', 'question.delete_service', name)
                .setAction(() => {
                    let service = application.services[this.group][name]
                    application.removeService(service, this.group)
                    this.entryName = ''
                    this.entryType = null
                    this.showServices()
                })
                .setAcceptLabel('button.delete')
                .setI18N(application.i18n)
                .show()
        } else {
            let question = this.entryType === Metadata.FILE ? 'question.delete_file' : 'question.delete_folder'

            ConfirmDialog.create('title.delete_from_cloud', question, name)
                .setAction(() => this.deletePath(this.basePath + '/' + name))
                .setAcceptLabel('button.delete')
                .setI18N(application.i18n)
                .show()
        }
    }

    showFolderDialog() {
        const application = this.application
        const dialog = new Dialog('title.create_folder_in_cloud')
        dialog.setSize(250, 130)
        dialog.setI18N(application.i18n)
        let nameElem = dialog.addTextField('folder_name', 'label.folder_name')
        nameElem.setAttribute('spellcheck', 'false')

        dialog.addButton('folder_accept', 'button.create', () => dialog.onAccept())
        dialog.addButton('folder_cancel', 'button.cancel', () => dialog.onCancel())

        dialog.onAccept = () => {
            this.makeFolder(this.basePath + '/' + nameElem.value)
            dialog.hide()
        }
        dialog.onCancel = () => {
            dialog.hide()
        }
        dialog.onShow = () => {
            nameElem.focus()
        }
        dialog.show()
    }

    showUploadDialog() {
        let inputFile = document.createElement('input')

        inputFile.type = 'file'

        inputFile.addEventListener('change', event => this.upload(inputFile.files))
        inputFile.click()
    }

    openPath(path, onSuccess) {
        this.showProgressBar('Reading...')

        this.service.open(
            path,
            result => this.handleOpenResult(path, result, onSuccess),
            data => this.setProgress(data.progress, data.message)
        )
    }

    savePath(path, data, onSuccess) {
        this.showProgressBar('Saving...')

        this.service.save(
            path,
            data,
            result => this.handleSaveResult(path, data, result, onSuccess),
            data => this.setProgress(data.progress, data.message)
        )
    }

    deletePath(path, onSuccess) {
        this.showProgressBar('Deleting...')
        this.service.remove(path, result => this.handleDeleteResult(path, result, onSuccess))
    }

    makeFolder(path, onSuccess) {
        this.showProgressBar('Creating folder...')
        this.service.makeCollection(path, result => this.handleMakeFolderResult(path, result, onSuccess))
    }

    download(path, onSuccess) {
        this.showProgressBar('Downloading file...')
        this.service.open(
            path,
            result => this.handleDownloadResult(path, result, onSuccess),
            data => this.setProgress(data.progress)
        )
    }

    upload(files, onSuccess) {
        if (files.length > 0) {
            const application = this.application
            let file = files[0]
            let reader = new FileReader()
            reader.onload = event => {
                const data = event.target.result
                const path = this.basePath + '/' + file.name
                this.showProgressBar('Uploading file...')
                this.service.save(
                    path,
                    data,
                    result => {
                        this.entryName = file.name
                        this.entryType = Metadata.FILE
                        this.handleUploadResult(files, result, onSuccess)
                    },
                    data => this.setProgress(data.progress)
                )
            }
            reader.readAsText(file)
        }
    }

    handleOpenResult(path, result, onSuccess) {
        this.showButtonsPanel()

        if (result.status === Result.OK) {
            if (onSuccess) onSuccess()

            if (result.entries) {
                this.entryName = ''
                this.entryType = null
                this.showDirectory(path, result)
            } else {
                this.openFile(this.service.url + path, result.data)
            }
        } else {
            this.handleError(
                result,
                false,
                () => this.openPath(path),
                () => {
                    if (path === '/') this.service = null
                }
            )
        }
    }

    handleSaveResult(path, data, result, onSuccess) {
        const application = this.application
        this.showButtonsPanel()

        if (result.status === Result.OK) {
            if (onSuccess) onSuccess()

            Toast.create('message.file_saved')
                .setI18N(application.i18n)
                .show()

            // reload current directory
            this.openPath(this.basePath)
        } else {
            this.handleError(result, true, () => this.savePath(path, data, onSuccess))
        }
    }

    handleDeleteResult(path, result, onSuccess) {
        const application = this.application
        this.showButtonsPanel()

        if (result.status === Result.OK) {
            if (onSuccess) onSuccess()

            if (this.entryType === Metadata.COLLECTION) {
                Toast.create('message.folder_deleted')
                    .setI18N(application.i18n)
                    .show()
            } else {
                Toast.create('message.file_deleted')
                    .setI18N(application.i18n)
                    .show()
            }

            this.entryName = ''
            this.entryType = null

            // reload basePath
            this.openPath(this.basePath)
        } else {
            this.handleError(result, true, () => this.deletePath(path))
        }
    }

    handleMakeFolderResult(path, result, onSuccess) {
        const application = this.application
        this.showButtonsPanel()

        if (result.status === Result.OK) {
            if (onSuccess) onSuccess()

            Toast.create('message.folder_created')
                .setI18N(application.i18n)
                .show()

            this.entryName = ''
            this.entryType = null

            // reload basePath
            this.openPath(this.basePath)
        } else {
            this.handleError(result, true, () => this.makeFolder(path))
        }
    }

    handleDownloadResult(path, result, onSuccess) {
        this.showButtonsPanel()

        if (result.status === Result.OK) {
            if (onSuccess) onSuccess()

            const data = result.data
            if (this.downloadUrl) {
                window.URL.revokeObjectURL(this.downloadUrl)
            }
            const blob = new Blob([data], { type: 'application/octet-stream' })
            this.downloadUrl = window.URL.createObjectURL(blob)
            let linkElem = document.createElement('a')
            linkElem.download = this.entryName
            linkElem.target = '_blank'
            linkElem.href = this.downloadUrl
            linkElem.style.display = 'block'
            linkElem.click()
        } else {
            this.handleError(result, false, () => this.download(path))
        }
    }

    handleUploadResult(files, result, onSuccess) {
        const application = this.application
        this.showButtonsPanel()

        if (result.status === Result.OK) {
            if (onSuccess) onSuccess()

            Toast.create('message.file_saved')
                .setI18N(application.i18n)
                .show()

            // reload current directory
            this.openPath(this.basePath)
        } else {
            this.handleError(result, true, () => this.upload(files))
        }
    }

    showServices() {
        const application = this.application

        this.basePath = '/'
        const COLLECTION = Metadata.COLLECTION

        this.directoryElem.innerHTML = '/'
        this.entriesElem.innerHTML = ''
        let firstLink = null
        for (let serviceName in application.services[this.group]) {
            let service = application.services[this.group][serviceName]
            let entryElem = document.createElement('li')
            entryElem.className = 'entry service'
            entryElem.entryName = service.name
            let linkElem = document.createElement('a')
            linkElem.href = '#'
            linkElem.innerHTML = service.description || service.name
            linkElem.addEventListener('click', event => this.onEntry(service.name, COLLECTION))
            linkElem.addEventListener('dblclick', event => this.openEntry())
            entryElem.appendChild(linkElem)
            if (firstLink === null) firstLink = linkElem
            this.entriesElem.appendChild(entryElem)
        }
        this.highlight()
        this.updateButtons()
        if (firstLink) firstLink.focus()
    }

    showDirectory(path, result) {
        const application = this.application
        const service = this.service

        this.basePath = path
        const FILE = Metadata.FILE

        if (path === '/') {
            // service home
            this.directoryElem.innerHTML = service.description || service.name
        } else {
            this.directoryElem.innerHTML = result.metadata.name
        }
        let entries = result.entries
        entries.sort(this.entryComparator)
        this.entriesElem.innerHTML = ''
        let firstLink = null
        for (let entry of entries) {
            let entryElem = document.createElement('li')
            let className = 'entry ' + (entry.type === FILE ? 'file' : 'collection')
            entryElem.className = className
            entryElem.entryName = entry.name
            let linkElem = document.createElement('a')
            linkElem.href = '#'
            let label = entry.description
            let size = entry.size
            if (entry.type === FILE && size > 0 && this.showFileSize) {
                label += ' ('
                if (size > 1000000) label += (size / 1000000).toFixed(0) + ' Mb'
                else if (size > 1000) label += (size / 1000).toFixed(0) + ' Kb'
                else label += '1 Kb'
                label += ')'
            }
            linkElem.innerHTML = label
            linkElem.addEventListener('click', event => this.onEntry(entry.name, entry.type))
            linkElem.addEventListener('dblclick', event => this.openEntry())
            entryElem.appendChild(linkElem)
            if (firstLink === null) firstLink = linkElem
            this.entriesElem.appendChild(entryElem)
        }
        this.highlight()
        this.updateButtons()
        if (firstLink) firstLink.focus()
    }

    highlight() {
        const entriesElem = this.entriesElem
        for (let i = 0; i < entriesElem.childNodes.length; i++) {
            let childNode = entriesElem.childNodes[i]
            if (childNode.nodeName === 'LI') {
                if (childNode.entryName === this.entryName) {
                    childNode.classList.add('selected')
                } else {
                    childNode.classList.remove('selected')
                }
            }
        }
    }

    goHome() {
        this.entryName = ''
        this.entryType = null
        this.service = null
        this.showServices()
    }

    goBack() {
        if (this.service === null) return

        this.entryName = ''
        this.entryType = null

        if (this.basePath === '/') {
            this.service = null
            this.showServices()
        } else {
            const index = this.basePath.lastIndexOf('/')
            if (index <= 0) {
                this.openPath('/')
            } else {
                this.openPath(this.basePath.substring(0, index))
            }
        }
    }

    onEntry(entryName, entryType) {
        this.entryName = entryName
        this.entryType = entryType
        this.highlight()
        this.updateButtons()
    }

    openEntry() {
        let path
        if (this.service === null) {
            this.service = this.application.services[this.group][this.entryName]
            path = '/'
        } else {
            path = this.basePath
            if (!this.basePath.endsWith('/')) path += '/'
            path += this.entryName
        }
        this.openPath(path)
    }

    openFile(url, data) {
        this.application.progressBar.visible = false
        this.showButtonsPanel()
    }

    updateButtons() {
        const children = this.buttonsPanelElem.children
        let firstVisibleButton = null
        for (let child of children) {
            if (child._isVisible()) {
                child.style.display = 'inline'
                if (firstVisibleButton === null) firstVisibleButton = child
            } else {
                child.style.display = 'none'
            }
        }
        if (firstVisibleButton) {
            firstVisibleButton.focus()
        }
    }

    showButtonsPanel() {
        this.buttonsPanelElem.style.display = 'block'
        this.application.progressBar.visible = false
    }

    showProgressBar(message = '') {
        this.buttonsPanelElem.style.display = 'none'
        this.application.progressBar.message = message
        this.application.progressBar.progress = undefined
        this.application.progressBar.visible = true
    }

    setProgress(progress, message) {
        this.application.progressBar.progress = progress
        if (message) {
            this.application.progressBar.message = message
        }
    }

    entryComparator(a, b) {
        const COLLECTION = Metadata.COLLECTION
        const FILE = Metadata.FILE

        if (a.type === COLLECTION && b.type === FILE) return -1
        if (a.type === FILE && b.type === COLLECTION) return 1
        if (a.name < b.name) return -1
        if (a.name > b.name) return 1
        return 0
    }

    handleError(result, isWriteAction, onLogin, onFailed) {
        if (result.status === Result.INVALID_CREDENTIALS) {
            this.requestCredentials('message.invalid_credentials', onLogin, onFailed)
        } else if (result.status === Result.FORBIDDEN) {
            this.requestCredentials(isWriteAction ? 'message.action_denied' : 'message.access_denied', onLogin, onFailed)
        } else {
            if (onFailed) onFailed()

            MessageDialog.create('ERROR', result.message)
                .setClassName('error')
                .setI18N(this.application.i18n)
                .show()
        }
    }

    requestCredentials(message, onLogin, onFailed) {
        const loginDialog = new LoginDialog(this.application, message)
        loginDialog.login = (username, password) => {
            this.service.username = username
            this.service.password = password
            if (onLogin) onLogin()
        }
        loginDialog.onCancel = () => {
            loginDialog.hide()
            if (onFailed) onFailed()
        }
        loginDialog.show()
    }
}

export { FileExplorer }