//
//  Image.swift
//  PrySDR
//
//  Created by Jacky Jack on 27/12/2024.
//

import Foundation
import AppKit

// https://stackoverflow.com/questions/30958427/pixel-array-to-uiimage-in-swift
public struct PixelData {
    var a: UInt8
    var r: UInt8
    var g: UInt8
    var b: UInt8
}

public class SimpleImage {
    
    private var pixels: [PixelData] = []
    private var width:Int = 0
    private var height:Int = 0
    
    init(width: Int, height: Int) {
        self.width = width
        self.height = height
        pixels = .init(repeating: .init(a: 255, r: 0, g: 0, b: 0), count: width*height)
    }
    
    
    func drawPalletLine(line: Int, pixelLine:[Float]) {
        for i in 0..<self.width {
            var pixel = pixelLine[i]
            if pixel>255.0 {
                //print("values to high")
                pixel = 255.0
            }
            if pixel < 0.0 {
                pixel = 0.0
            }
            self.pixels[line*self.width + i].a = 255
            self.pixels[line*self.width + i].r = UInt8(pixel)
            self.pixels[line*self.width + i].g = UInt8(pixel)
            self.pixels[line*self.width + i].b = UInt8(pixel)
        }
    }
    
    func drawPixel(_ w: Int, _ h: Int, _ pixel: PixelData) {
        self.pixels[h*self.height+w] = pixel
    }
    
    func toCGImage() -> CGImage? {
        guard self.width > 0 && self.height > 0 else { return nil }
        guard self.pixels.count == self.width * self.height else { return nil }

            let rgbColorSpace = CGColorSpaceCreateDeviceRGB()
            let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.premultipliedFirst.rawValue)
            let bitsPerComponent = 8
            let bitsPerPixel = 32

        var data = self.pixels // Copy to mutable []
            guard let providerRef = CGDataProvider(data: NSData(bytes: &data,
                                    length: data.count * MemoryLayout<PixelData>.size)
                )
                else { return nil }

            guard let cgim = CGImage(
                width: self.width,
                height: self.height,
                bitsPerComponent: bitsPerComponent,
                bitsPerPixel: bitsPerPixel,
                bytesPerRow: self.width * MemoryLayout<PixelData>.size,
                space: rgbColorSpace,
                bitmapInfo: bitmapInfo,
                provider: providerRef,
                decode: nil,
                shouldInterpolate: true,
                intent: .defaultIntent
                )
                else { return nil }

            return cgim
    }
    
    func toNSImage() -> NSImage? {
        guard let cgim = toCGImage() else { return nil }
        return NSImage(cgImage: cgim, size:.zero)
    }
    
    func saveAsJPEG(_ image: NSImage, _ name: String) {
            if let imageData = image.tiffRepresentation {
                do {
                    let bundlePath = Bundle.main.resourcePath!
                    let imageUrl = URL(fileURLWithPath:bundlePath+"/"+name)
                    try imageData.write(to: imageUrl)
                    
                } catch {
                    print("Cant save image to disk")
                }
                
            } else {
                print("cant get tiff representation")
            }
    }
    
    func saveAsJPEG(_ name: String) {
        if let img = self.toNSImage() {
            saveAsJPEG(img, name)
        }
    }
}