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

const ArrayList = std.ArrayList;
const Endian = std.builtin.Endian;

const SoundNode = @import("soundnode.zig").SoundNode;
const Activity = @import("activity.zig").Activity;
const SoundSettings = @import("settings.zig").SoundSettings;
const utility = @import("utility.zig");


pub fn singleSineTick(st: *SoundSettings, freq: f64, t: u32, phase: f64) f64 {
	const ft: f64 = @floatFromInt(t);
	return math.sin(st.sine_multiplier * freq * ft - phase * utility.tau);
}

pub fn main() !void {

	const allocator = std.heap.c_allocator;
	
	// Initializing sound settings
	const settings: SoundSettings = SoundSettings{};
	
	// Creating a list of soundnodes
	var soundnodes = ArrayList(*SoundNode).init(allocator);
	defer soundnodes.deinit();
			
	// Determining length of resulting audio in ticks
	const start_tick: u32 = 0;
	var end_tick: u32 = 44100 * 10;	
	
	// Loading the input binary code, preparing registers
	const file = try std.fs.cwd().openFile("source.snmb", .{});
	defer file.close();
	
	const stat = try file.stat();
	const buf: []u8 = try file.readToEndAlloc(allocator, stat.size);
	
	var cursor: u32 = 0;
	
	var opcode: u16 = 0;
	var tick_start: u32 = 0;
	var tick_end: u32 = 0;
	var src_node: u16 = 0;
	var trg_node: u16 = 0;
	var op1: f64 = 0;
	var op2: f64 = 0;
	var op3: f64 = 0;
	var op4: f64 = 0;
	var op5: f64 = 0;
	var op6: f64 = 0;
	
	// Preparing to write wav data to stdout
	const stdout_file = std.io.getStdOut().writer();
	var bw = std.io.bufferedWriter(stdout_file);
	const stdout = bw.writer();
	
	// Writing WAV header
	
	try stdout.writeAll("RIFF");
	
	try stdout.writeInt(
		u32,
		36 + (end_tick * 2 * settings.sample_width),
		Endian.little,
	);
	
	try stdout.writeAll("WAVE");
	try stdout.writeAll("fmt ");
		
	try stdout.writeInt(u32, 16, Endian.little);
	try stdout.writeInt(u16, 1, Endian.little);
	try stdout.writeInt(u16, 2, Endian.little);
	try stdout.writeInt(u32, settings.sample_rate, Endian.little);
	
	const block_align: u16 = @intCast(2 * settings.sample_width);
	
	try stdout.writeInt(u32, @as(u32, block_align) * settings.sample_rate, Endian.little);
	try stdout.writeInt(u16, block_align, Endian.little);
	try stdout.writeInt(u16, settings.bit_depth, Endian.little);

	try stdout.writeAll("data");
	
	// Setting up tick iteration
	var tick: u32 = start_tick;
	var sample: i24 = 0.0;
	var left: *SoundNode = undefined;
	var right: *SoundNode = undefined;
	
	var nextopcodetick: u32 = 0;
	
	while (tick < end_tick) {
			
		if (tick%44100 == 0) {
			print("T {d} ", .{tick});
		}	
			
		if (tick == nextopcodetick) {
			
			while (cursor < buf.len) {
				
				opcode = std.mem.readVarInt(u16, buf[cursor..cursor+2], .big);
				//print("----\nCURRENT TICK {d}\nOPCODE {d}    :: {any}\n", .{tick, opcode, buf[cursor..cursor+2]});
				cursor += 2;
				
				tick_start = std.mem.readVarInt(u32, buf[cursor..cursor+4], .big);
				//print("TICKSTART {d} :: {any}\n", .{tick_start, buf[cursor..cursor+4]});
				cursor += 4;
				
				if (tick_start > tick) {
					cursor -= 6;
					nextopcodetick = tick_start;
					break;
					
				} else {			
								
					tick_end = std.mem.readVarInt(u32, buf[cursor..cursor+4], .big);
					//print("TICKEND {d}   :: {any}\n", .{tick_end, buf[cursor..cursor+4]});
					cursor += 4;
					
					src_node = std.mem.readVarInt(u16, buf[cursor..cursor+2], .big);
					//print("SRCNODE {d}   :: {any}\n", .{src_node, buf[cursor..cursor+2]});
					cursor += 2;
					
					trg_node = std.mem.readVarInt(u16, buf[cursor..cursor+2], .big);
					//print("TRGNODE {d}   :: {any}\n", .{trg_node, buf[cursor..cursor+2]});
					cursor += 2;
					
					op1 = @bitCast(std.mem.readVarInt(u64, buf[cursor..cursor+8], .big));
					//print("OP1     {d}   :: {any}\n", .{op1, buf[cursor..cursor+8]});
					cursor += 8;
					
					op2 = @bitCast(std.mem.readVarInt(u64, buf[cursor..cursor+8], .big));
					//print("OP2     {d}   :: {any}\n", .{op2, buf[cursor..cursor+8]});
					cursor += 8;
					
					op3 = @bitCast(std.mem.readVarInt(u64, buf[cursor..cursor+8], .big));
					//print("OP3     {d}   :: {any}\n", .{op3, buf[cursor..cursor+8]});
					cursor += 8;
					
					op4 = @bitCast(std.mem.readVarInt(u64, buf[cursor..cursor+8], .big));
					//print("OP4     {d}   :: {any}\n", .{op4, buf[cursor..cursor+8]});
					cursor += 8;
					
					op5 = @bitCast(std.mem.readVarInt(u64, buf[cursor..cursor+8], .big));
					//print("OP5     {d}   :: {any}\n", .{op5, buf[cursor..cursor+8]});
					cursor += 8;
					
					op6 = @bitCast(std.mem.readVarInt(u64, buf[cursor..cursor+8], .big));
					//print("OP6     {d}   :: {any}\n", .{op6, buf[cursor..cursor+8]});
					cursor += 8;
					
					// Executing opcodes
					
					switch (opcode) {
						
						0 => {
							const nodename = try std.fmt.allocPrint(allocator, "{d}", .{src_node});
	
							const sn = try SoundNode.create(allocator, nodename);
							//print("Added node {s} at tick {d}\n", .{nodename, tick});
							try soundnodes.append(sn);
							
							try sn.s("basefreq", @as(f64, 440));
							try sn.s("gain", @as(f64, 1));
							try sn.s("phase", @as(f64, 0));
							
						},
						
						1 => {
							const src = soundnodes.items[src_node];
							const trg = soundnodes.items[trg_node];
							//print("Wired nodes at tick {d}\n", .{tick});
							
							try trg.wire_in.append(src);
							try src.wire_targets.append(trg);
						},
						
						2 => {
							const src = soundnodes.items[src_node];
							const trg = soundnodes.items[trg_node];
							
							//print("Aired nodes at tick {d}\n", .{tick});
							try trg.air_in.append(src);
							try src.air_targets.append(trg);
						},
						
						3 => {
							end_tick = tick_end;
							
							try stdout.writeInt(
								u32,
								end_tick * 2 * settings.sample_width,
								Endian.little,
							);
							//print("End tick set to {d}\n", .{end_tick});
						},
						
						else => {
							
							const src = soundnodes.items[src_node];
							const a = try Activity.create(allocator, tick_start, tick_end, opcode, src, [6]f64{op1, op2, op3, op4, op5, op6});
							
							//print("Set activity {d} for node {d} s at tick {d}\n", .{opcode, src_node, tick});
							try src.activities.append(a);
							
							if (src.activities.items.len == 1) {
								src.active = 1;
							}
							
						},
						
					}
					
				}
			
			}
		
		}
		
		//All but left and right
	
		for (soundnodes.items[2..], 0..) |soundnode, i| {
			
			if (soundnode.active == 1) {
				
				var toremove = ArrayList(usize).init(allocator);
				defer toremove.deinit();
					
				for (soundnode.activities.items, 0..) |activity, j| {
									
					if (tick <= activity.end_tick and tick >= activity.start_tick) {
						try activity.do();
					} else if (tick >= activity.end_tick) {
						try toremove.append(j);
					}
				}
			
				var j: usize = toremove.items.len;
				
				while (j > 0) {
					j -= 1;
					const activity_ind = toremove.items[j];				
					_ = soundnode.activities.swapRemove(activity_ind);
					if (soundnode.activities.items.len == 0) {
						soundnode.active = 0;
					}
				}
			
			}
		
			soundnode.fab.increment_tick();
			_ = i;
		}
	
		//Left and right
	
		for (soundnodes.items[0..2], 0..) |soundnode, i| {
			
			var toremove = ArrayList(usize).init(allocator);
			defer toremove.deinit();
			
			for (soundnode.activities.items, 0..) |activity, j| {
				
				if (tick <= activity.end_tick and tick >= activity.start_tick) {
					try activity.do();
				} else if (tick >= activity.end_tick) {
					try toremove.append(j);
				}
					
			}
		
			var j: usize = toremove.items.len;
			
			while (j > 0) {
				j -= 1;
				const activity_ind = toremove.items[j];				
				_ = soundnode.activities.swapRemove(activity_ind);
			}			
			
			_ = i;
		}
		
		//Calculating and writing output amps
			
		left = soundnodes.items[0];
		right = soundnodes.items[1];
		
		const current_r_amp_left = left.fab.get_current_r_amp();
		sample = @intFromFloat(current_r_amp_left * settings.max_amp_multiplier);
		try stdout.writeInt(i24, sample, Endian.little);
				
		const current_r_amp_right = right.fab.get_current_r_amp();
		sample = @intFromFloat(current_r_amp_right * settings.max_amp_multiplier);		
		try stdout.writeInt(i24, sample, Endian.little);
		
		left.fab.increment_tick();
		right.fab.increment_tick();
		tick += 1;
	
	}
	
	try bw.flush();
			
}