ShaderManiaDocument.swift

//
//  ShaderManiaDocument.swift
//  Shared
//
//  Created by Markus Moenig on 19/11/20.
//

import SwiftUI
import UniformTypeIdentifiers
import Combine

extension UTType {
    static var shaderManiaShader: UTType {
        UTType(exportedAs: "com.ShaderMania.shader")
    }
}

struct ShaderManiaDocument: FileDocument {
    
    var core    = Core()
    var updated = false
    
    let exportImage          = PassthroughSubject<Void, Never>()
    let help                 = PassthroughSubject<Void, Never>()

    init() {
    }

    static var readableContentTypes: [UTType] { [.shaderManiaShader] }
    static var writableContentTypes: [UTType] { [.shaderManiaShader, .png] }

    /*
    init(configuration: ReadConfiguration) throws {
        guard let data = configuration.file.regularFileContents,
              let string = String(data: data, encoding: .utf8)
        else {
            throw CocoaError(.fileReadCorruptFile)
        }
        text = string
    }*/
    
    init(configuration: ReadConfiguration) throws {
        guard let data = configuration.file.regularFileContents,
                let folder = try? JSONDecoder().decode(AssetFolder.self, from: data)
        else {
            throw CocoaError(.fileReadCorruptFile)
        }
        if data.isEmpty == false {
            core.assetFolder = folder
            core.assetFolder.core = core
            
            // Make sure there is a selected asset
            if core.assetFolder.assets.count > 0 {
                core.assetFolder.current = core.assetFolder.assets[0]
            }
        }
    }
    
    /*
    func fileWrapper(configuration: WriteConfiguration) throws -> FileWrapper {
        let data = text.data(using: .utf8)!
        return .init(regularFileWithContents: data)
    }*/
    
    func fileWrapper(configuration: WriteConfiguration) throws -> FileWrapper {
        var data = Data()
        
        let encodedData = try? JSONEncoder().encode(core.assetFolder)
        if let json = String(data: encodedData!, encoding: .utf8) {
            data = json.data(using: .utf8)!
        }
        
        return .init(regularFileWithContents: data)
    }
}