From 495d50ba109499cab7f7306773d2cb0b058d3d3c Mon Sep 17 00:00:00 2001
From: Dan Jones <danjones@goodevilgenius.org>
Date: Mon, 9 Dec 2024 14:34:01 -0600
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=9B=20Account=20for=20file=20ids=20>?=
 =?UTF-8?q?=209?=
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---
 .gitignore         |  1 +
 blocks.go          | 17 +++++++++--------
 blocks_test.go     | 11 +++++------
 checksum.go        | 14 ++++++++++++++
 cmd/defrag/main.go |  9 ++++++++-
 defrag.go          |  6 +++---
 defrag_test.go     | 19 -------------------
 7 files changed, 40 insertions(+), 37 deletions(-)
 create mode 100644 checksum.go
 delete mode 100644 defrag_test.go

diff --git a/.gitignore b/.gitignore
index 6f72f89..a6782c6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -23,3 +23,4 @@ go.work.sum
 
 # env file
 .env
+defrag
diff --git a/blocks.go b/blocks.go
index 2c90f7a..20f6051 100644
--- a/blocks.go
+++ b/blocks.go
@@ -1,30 +1,31 @@
 package defrag
 
 import (
-	"bytes"
 	"strconv"
-	"strings"
 )
 
-func Blocks(diskMap []byte) ([]byte, error) {
+func Blocks(diskMap []byte) ([]int, error) {
 	current := 0
 	onFile := false
-	buff := bytes.Buffer{}
+	out := []int{}
 	for _, by := range diskMap {
 		count, err := strconv.Atoi(string(by))
 		if err != nil {
 			return nil, err
 		}
 		onFile = !onFile
+
 		if count == 0 {
 			continue
 		}
-		append := "."
+		val := -1
 		if onFile {
-			append = strconv.Itoa(current)
+			val = current
 			current++
 		}
-		buff.WriteString(strings.Repeat(append, count))
+		for idx := 0; idx < count; idx++ {
+			out = append(out, val)
+		}
 	}
-	return buff.Bytes(), nil
+	return out, nil
 }
diff --git a/blocks_test.go b/blocks_test.go
index 1e1831c..b50bd33 100644
--- a/blocks_test.go
+++ b/blocks_test.go
@@ -7,16 +7,15 @@ import (
 )
 
 type tt struct {
-	name      string
-	diskMap   []byte
-	blocks    []byte
-	defragged []byte
+	name    string
+	diskMap []byte
+	blocks  []int
 }
 
 func sampleTests() []tt {
 	return []tt{
-		{"short", []byte("12345"), []byte("0..111....22222"), []byte("022111222......")},
-		{"longer", []byte("2333133121414131402"), []byte("00...111...2...333.44.5555.6666.777.888899"), []byte("0099811188827773336446555566..............")},
+		{"short", []byte("12345"), []int{0, -1, -1, 1, 1, 1, -1, -1, -1, -1, 2, 2, 2, 2, 2}},
+		{"longer", []byte("2333133121414131402"), []int{0, 0, -1, -1, -1, 1, 1, 1, -1, -1, -1, 2, -1, -1, -1, 3, 3, 3, -1, 4, 4, -1, 5, 5, 5, 5, -1, 6, 6, 6, 6, -1, 7, 7, 7, -1, 8, 8, 8, 8, 9, 9}},
 	}
 }
 
diff --git a/checksum.go b/checksum.go
new file mode 100644
index 0000000..0b934b0
--- /dev/null
+++ b/checksum.go
@@ -0,0 +1,14 @@
+package defrag
+
+// import "strconv"
+
+func Checksum(blocks []int) (sum int, err error) {
+	for idx, fileByte := range blocks {
+		if fileByte == -1 {
+			break
+		}
+
+		sum += idx * fileByte
+	}
+	return
+}
diff --git a/cmd/defrag/main.go b/cmd/defrag/main.go
index 99bdecf..e5e7fd7 100644
--- a/cmd/defrag/main.go
+++ b/cmd/defrag/main.go
@@ -29,6 +29,7 @@ func main() {
 
 	blocks, err := defrag.Blocks(input)
 	handleErr(err)
+
 	err = defrag.Defrag(blocks)
 	handleErr(err)
 
@@ -36,5 +37,11 @@ func main() {
 	fmt.Printf("%s\n", input)
 
 	fmt.Println("Got this")
-	fmt.Printf("%s\n", blocks)
+	fmt.Printf("%v\n", blocks)
+
+	sum, err := defrag.Checksum(blocks)
+	handleErr(err)
+
+	fmt.Println("Checksum:")
+	fmt.Printf("%d\n", sum)
 }
diff --git a/defrag.go b/defrag.go
index 82204d2..8623c4f 100644
--- a/defrag.go
+++ b/defrag.go
@@ -2,18 +2,18 @@ package defrag
 
 // Defrag performs an in-place sort of blocks.
 // If an error occurs during processing, it will be returned. The slice may have been partially sorted.
-func Defrag(blocks []byte) error {
+func Defrag(blocks []int) error {
 	lastPulled := len(blocks)
 	lastPushed := -1
 	for block := 0; block < len(blocks); block++ {
-		if blocks[block] != '.' {
+		if blocks[block] != -1 {
 			continue
 		}
 		if lastPulled <= block {
 			break
 		}
 		for swap := lastPulled - 1; swap > lastPushed; swap-- {
-			if blocks[swap] == '.' {
+			if blocks[swap] == -1 {
 				continue
 			}
 			blocks[block], blocks[swap] = blocks[swap], blocks[block]
diff --git a/defrag_test.go b/defrag_test.go
deleted file mode 100644
index 62f625b..0000000
--- a/defrag_test.go
+++ /dev/null
@@ -1,19 +0,0 @@
-package defrag
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/require"
-)
-
-func TestDefrag(t *testing.T) {
-	for _, testcase := range sampleTests() {
-		t.Run(testcase.name, func(sub *testing.T) {
-			blocks := make([]byte, len(testcase.blocks))
-			copy(blocks, testcase.blocks)
-			err := Defrag(blocks)
-			require.NoError(sub, err)
-			require.Equal(sub, testcase.defragged, blocks)
-		})
-	}
-}