From ca7dc1b6a54c8a4454286ff3400609dc046064dd Mon Sep 17 00:00:00 2001
From: Daisuke Maki <lestrrat+github@gmail.com>
Date: Sat, 14 Mar 2015 15:24:38 +0900
Subject: [PATCH] We don't need this globally unique ID stuff

This wasn't a distributed system, oops.
---
 action.go    |  4 ++++
 buffer.go    |  3 +--
 line.go      | 66 ++++++++++++----------------------------------------
 peco_test.go | 20 +++++++++++++++-
 4 files changed, 39 insertions(+), 54 deletions(-)

diff --git a/action.go b/action.go
index fa02315..d7b2350 100644
--- a/action.go
+++ b/action.go
@@ -206,6 +206,8 @@ func doSelectAll(i *Input, _ termbox.Event) {
 	for x := 0; x < b.Size(); x++ {
 		if l, err := b.LineAt(x); err == nil {
 			i.selection.Add(l)
+		} else {
+			i.selection.Remove(l)
 		}
 	}
 }
@@ -295,6 +297,8 @@ func doInvertSelection(i *Input, _ termbox.Event) {
 	for x := 0; x < b.Size(); x++ {
 		if l, err := b.LineAt(x); err == nil {
 			i.selection.Add(l)
+		} else {
+			i.selection.Remove(l)
 		}
 	}
 
diff --git a/buffer.go b/buffer.go
index ff2e342..18843f1 100644
--- a/buffer.go
+++ b/buffer.go
@@ -153,10 +153,9 @@ func (rlb *RawLineBuffer) Append(l Line) (Line, error) {
 	tracer.Printf("RawLineBuffer.Append: %s", l.DisplayString())
 	if rlb.capacity > 0 && len(rlb.lines) > rlb.capacity {
 		diff := len(rlb.lines) - rlb.capacity
-		// TODO Notify that we're invalidating these lines
 
 		// Golang's version of array realloc
-		rlb.lines = append(append([]Line(nil), rlb.lines[diff:]...), l)
+		rlb.lines = rlb.lines[diff:rlb.capacity:rlb.capacity]
 	} else {
 		rlb.lines = append(rlb.lines, l)
 	}
diff --git a/line.go b/line.go
index 8a4b1e4..3d5f904 100644
--- a/line.go
+++ b/line.go
@@ -3,68 +3,32 @@ package peco
 import (
 	"regexp"
 	"strings"
-	"sync"
-	"time"
 
 	"github.com/google/btree"
 )
 
-const (
-	epochOffset = 946684800
-	hostIDBits  = 16
-	serialBits  = 12
-	serialShift = 16
-	timeBits    = 36
-	timeShift   = 28
-)
-
 type idGen struct {
-	seed     uint64
-	mutex    *sync.Mutex
-	serialID int64
-	timeID   int64
-	timeout  int64
+	genCh chan uint64
 }
 
-func newIDGen(seed uint64) *idGen {
+func newIDGen() *idGen {
+	ch := make(chan uint64)
+	go func() {
+		var i uint64
+		for ; ; i++ {
+			ch <- i
+			if i >= uint64(1<<63)-1 {
+				i = 0
+			}
+		}
+	}()
 	return &idGen{
-		seed:     seed,
-		mutex:    &sync.Mutex{},
-		serialID: 1,
-		timeID:   time.Now().Unix(),
+		genCh: ch,
 	}
 }
 
 func (ig *idGen) create() uint64 {
-	ig.mutex.Lock()
-	defer ig.mutex.Unlock()
-
-	timeID := time.Now().Unix()
-	serialID := ig.serialID
-	if ig.timeID == 0 {
-		ig.timeID = timeID
-	}
-
-	if ig.timeID == timeID {
-		serialID++
-	} else {
-		serialID = 1
-	}
-
-	if serialID >= (1<<serialBits)-1 {
-		// Overflow:/ we recieved more than serialBits
-		panic("Serial bits overflowed")
-	}
-
-	ig.serialID = serialID
-	ig.timeID = timeID
-
-	timeBits := (timeID - epochOffset) << timeShift
-	serialBits := serialID << serialShift
-
-	id := uint64(timeBits) | uint64(serialBits) | ig.seed
-
-	return id
+	return <-ig.genCh
 }
 
 // Global var used to strips ansi sequences
@@ -116,7 +80,7 @@ type RawLine struct {
 	dirty         bool
 }
 
-var idGenerator = newIDGen(uint64(time.Now().Unix()))
+var idGenerator = newIDGen()
 
 func NewRawLine(v string, enableSep bool) *RawLine {
 	id := idGenerator.create()
diff --git a/peco_test.go b/peco_test.go
index 75f185e..d4871a7 100644
--- a/peco_test.go
+++ b/peco_test.go
@@ -1,6 +1,10 @@
 package peco
 
-import "sync"
+import (
+	"fmt"
+	"sync"
+	"testing"
+)
 
 type interceptorArgs []interface{}
 type interceptor struct {
@@ -35,3 +39,17 @@ func (i *interceptor) record(name string, args []interface{}) {
 	events[name] = append(v, interceptorArgs(args))
 }
 
+func TestIDGen(t *testing.T) {
+	lines := []*RawLine{}
+	for i := 0; i < 1000000; i++ {
+		lines = append(lines, NewRawLine(fmt.Sprintf("%d", i), false))
+	}
+
+	sel := NewSelection()
+	for _, l := range lines {
+		if sel.Has(l) {
+			t.Errorf("Collision detected %d", l.ID())
+		}
+		sel.Add(l)
+	}
+}