import { plugin } from "@ccms/api"
import * as fs from '@ccms/common/dist/fs'
import { provideSingletonNamed } from "@ccms/container"

const SCANNER_TYPE_NAME = 'js'

@provideSingletonNamed(plugin.PluginScanner, SCANNER_TYPE_NAME)
export class JSFileScanner implements plugin.PluginScanner {
    type: string = SCANNER_TYPE_NAME

    scan(target: any): plugin.PluginLoadMetadata[] {
        return this.scanFolder(fs.concat(root, target)).map((file) => this.read(file))
    }

    read(file: any): plugin.PluginLoadMetadata {
        return {
            file,
            path: file.canonicalPath || file.toString(),
            type: this.type,
            scanner: this,
            loaded: false
        }
    }

    load(loadMetadata: plugin.PluginLoadMetadata): plugin.PluginLoadMetadata {
        if (loadMetadata.type !== this.type) { return }
        this.updatePlugin(loadMetadata.file)
        delete require.cache[loadMetadata.path]
        loadMetadata.instance = require(loadMetadata.path)
        return loadMetadata
    }

    private scanFolder(folder: any): string[] {
        var files = []
        this.checkUpdateFolder(folder)
        // must check file is exist maybe is a illegal symbolic link file
        fs.list(folder).forEach((path: any) => {
            let file = path.toFile()
            if (file.exists() && file.getName().endsWith(".js")) {
                files.push(file)
            }
        })
        return files
    }

    private checkUpdateFolder(path: any) {
        var update = fs.file(path, "update")
        if (!update.exists()) {
            update.mkdirs()
        }
    }

    private updatePlugin(file: any) {
        var update = fs.file(fs.concat(file.parentFile, 'update', file.name))
        if (update.exists()) {
            console.i18n("ms.plugin.manager.build.update", { name: file.name })
            fs.move(update, file, true)
        }
    }

}