default:

	zig run main.zig

// PPM image format -  https://netpbm.sourceforge.net/doc/ppm.html

const std = @import("std");

const debug = @import("std").debug;

const ImageSize = 600;

const Color = struct {

    r: u8,

    g: u8,

    b: u8,

    pub fn initRandom() Color {

        const rand = std.crypto.random;

        return Color{

            .r = rand.int(u8),

            .g = rand.int(u8),

            .b = rand.int(u8),

        };

    }

    pub fn toString(self: Color) []const u8 {

        return std.fmt.allocPrint(std.heap.page_allocator, "{d} {d} {d} ", .{ self.r, self.g, self.b }) catch unreachable;

    }

};

pub fn main() !void {

    const imageFile = try std.fs.cwd().createFile("image.ppm", .{});

    defer imageFile.close();

    // NOTE: This should be done at compile time instead since the data is

    //       known in advance. I am leaving this here as a reference.

    // const header: []const u8 = std.fmt.allocPrint(std.heap.page_allocator, "P3\n{d} {d}\n255\n", .{ ImageSize, ImageSize }) catch unreachable;

    // NOTE: This is done at compile time instead. It does look a bit ugly

    //       and there must be a better way of doing this. Good enough!

    const header = "P3\n" ++ std.fmt.comptimePrint("{d}", .{ImageSize}) ++ " " ++ std.fmt.comptimePrint("{d}", .{ImageSize}) ++ "\n255\n";

    _ = try imageFile.write(header);

    for (0..(ImageSize * ImageSize)) |_| {

        const color = Color.initRandom();

        _ = try imageFile.write(color.toString());

    }

}