From 00637026ea05ab028b437b48693ed66be1ed4a9a Mon Sep 17 00:00:00 2001
From: Muaz Ahmad <mahmad2000@protonmail.com>
Date: Mon, 27 Nov 2023 15:42:01 +0500
Subject: [PATCH] file reading and queue prepend

---
 src/input.zig | 62 +++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 58 insertions(+), 4 deletions(-)

diff --git a/src/input.zig b/src/input.zig
index 1e8d12a..a7c84a0 100644
--- a/src/input.zig
+++ b/src/input.zig
@@ -3,8 +3,62 @@ const std = @import("std");
 const util = @import("util.zig");
 const threads = @import("threads.zig");
 
-pub fn main_loop(f: std.fs.File, buffs: util.Buffers, thread_mgr: threads.ThreadManager) !void {
-    _ = thread_mgr;
-    _ = buffs;
-    _ = f;
+inline fn lum_idxs(i: usize, j: usize) struct { usize, usize, usize } {
+    return .{
+        i / 2,
+        j / 2,
+        2 * (i % 2) + (j % 2),
+    };
+}
+
+fn read_lum(f: std.fs.File, source_buff: [][][4]util.Block, target_buff: [][][4]util.BlockQuantized, io_buff: []u8, queue: *util.JobQueue) !void {
+    const block_h = source_buff.len;
+    const block_w = source_buff[0].len;
+
+    for (0..block_h * 2) |i| {
+        _ = try f.read(io_buff);
+        var io_idx: usize = 0;
+        for (0..8) |I| {
+            for (0..block_w * 2) |j| {
+                const idxs = lum_idxs(i, j);
+                @memcpy(source_buff[idxs.@"0"][idxs.@"1"][idxs.@"2"][I * 8 .. (I + 1) * 8], io_buff[io_idx .. io_idx + 8]);
+                io_idx += 8;
+                if (I == 7) {
+                    try queue.prepend(util.Job{
+                        .source = &source_buff[idxs.@"0"][idxs.@"1"][idxs.@"2"],
+                        .target = &target_buff[idxs.@"0"][idxs.@"1"][idxs.@"2"],
+                    });
+                }
+            }
+        }
+    }
+}
+
+fn read_chrom(f: std.fs.File, source_buff: [][]util.Block, target_buff: [][]util.BlockQuantized, io_buff: []u8, queue: *util.JobQueue) !void {
+    const block_h = source_buff.len;
+    const block_w = source_buff[0].len;
+
+    for (0..block_h) |i| {
+        _ = try f.read(io_buff);
+        var io_idx: usize = 0;
+        for (0..8) |I| {
+            for (0..block_w) |j| {
+                @memcpy(source_buff[i][j][I * 8 .. (I + 1) * 8], io_buff[io_idx .. io_idx + 8]);
+                io_idx += 8;
+                if (I == 7) {
+                    try queue.prepend(util.Job{
+                        .source = &source_buff[i][j],
+                        .target = &target_buff[i][j],
+                    });
+                }
+            }
+        }
+    }
+}
+
+pub fn main_loop(f: std.fs.File, buffs: util.Buffers, thread_mgr: threads.ThreadManager) !void {
+    try read_lum(f, buffs.Y, buffs.Y_quant, buffs.input_buff, thread_mgr.queue_wrp.queue);
+    try read_chrom(f, buffs.U, buffs.U_quant, buffs.input_buff[0 .. buffs.input_buff.len / 2], thread_mgr.queue_wrp.queue);
+    try read_chrom(f, buffs.V, buffs.V_quant, buffs.input_buff[0 .. buffs.input_buff.len / 2], thread_mgr.queue_wrp.queue);
+    std.time.sleep(10000000);
 }