Merge branch 'improved-search' into v0.3.0

* improved-search:
  Make search more robust
  Remove RankFind
  Start with improved search

components/channels.go

@@ -3,9 +3,9 @@ package components
 import (
 	"fmt"
 	"html"
-	"strings"
 
 	"github.com/erroneousboat/termui"
+	"github.com/renstrom/fuzzysearch/fuzzy"
 )
 
 const (
@@ -97,6 +97,9 @@ type Channels struct {
 	SelectedChannel int // index of which channel is selected from the List
 	Offset          int // from what offset are channels rendered
 	CursorPosition  int // the y position of the 'cursor'
+
+	SearchMatches  []int // index of the search matches
+	SearchPosition int   // current position of a search match
 }
 
 // CreateChannels is the constructor for the Channels component
@@ -273,37 +276,71 @@ func (c *Channels) ScrollDown() {
 // when a match has been found the selected channel will then
 // be the channel that has been found
 func (c *Channels) Search(term string) {
-	for i, item := range c.List.Items {
-		if strings.Contains(item, term) {
+	c.SearchMatches = make([]int, 0)
 
-			// The new position
-			newPos := i
+	matches := fuzzy.Find(term, c.List.Items)
 
-			// Is the new position in range of the current view?
-			minRange := c.Offset
-			maxRange := c.Offset + (c.List.InnerBounds().Max.Y - 2)
-
-			if newPos < minRange {
-				// newPos is above, we need to scroll up.
-				c.SetSelectedChannel(i)
-
-				// How much do we need to scroll to get it into range?
-				c.Offset = c.Offset - (minRange - newPos)
-			} else if newPos > maxRange {
-				// newPos is below, we need to scroll down
-				c.SetSelectedChannel(i)
-
-				// How much do we need to scroll to get it into range?
-				c.Offset = c.Offset + (newPos - maxRange)
-			} else {
-				// newPos is inside range
-				c.SetSelectedChannel(i)
+	for _, m := range matches {
+		for i, item := range c.List.Items {
+			if m == item {
+				c.SearchMatches = append(c.SearchMatches, i)
+				break
 			}
-
-			// Set cursor to correct position
-			c.CursorPosition = (newPos - c.Offset) + 1
-
-			break
 		}
 	}
+
+	if len(c.SearchMatches) > 0 {
+		c.GotoPosition(0)
+		c.SearchPosition = 0
+	}
+}
+
+// GotoPosition is used by the search functionality to automatically
+// scroll to a specific location in the channels component
+func (c *Channels) GotoPosition(position int) {
+
+	// The new position
+	newPos := c.SearchMatches[position]
+
+	// Is the new position in range of the current view?
+	minRange := c.Offset
+	maxRange := c.Offset + (c.List.InnerBounds().Max.Y - 2)
+
+	if newPos < minRange {
+		// newPos is above, we need to scroll up.
+		c.SetSelectedChannel(newPos)
+
+		// How much do we need to scroll to get it into range?
+		c.Offset = c.Offset - (minRange - newPos)
+	} else if newPos > maxRange {
+		// newPos is below, we need to scroll down
+		c.SetSelectedChannel(newPos)
+
+		// How much do we need to scroll to get it into range?
+		c.Offset = c.Offset + (newPos - maxRange)
+	} else {
+		// newPos is inside range
+		c.SetSelectedChannel(newPos)
+	}
+
+	// Set cursor to correct position
+	c.CursorPosition = (newPos - c.Offset) + 1
+}
+
+// SearchNext allows us to cycle through the c.SearchMatches
+func (c *Channels) SearchNext() {
+	newPosition := c.SearchPosition + 1
+	if newPosition <= len(c.SearchMatches)-1 {
+		c.GotoPosition(newPosition)
+		c.SearchPosition = newPosition
+	}
+}
+
+// SearchPrev allows us to cycle through the c.SearchMatches
+func (c *Channels) SearchPrev() {
+	newPosition := c.SearchPosition - 1
+	if newPosition >= 0 {
+		c.GotoPosition(newPosition)
+		c.SearchPosition = newPosition
+	}
 }

config/config.go

@@ -72,6 +72,8 @@ func getDefaultConfig() Config {
 				"<next>":     "chat-down",
 				"C-f":        "chat-down",
 				"C-d":        "chat-down",
+				"n":          "channel-search-next",
+				"N":          "channel-search-prev",
 				"q":          "quit",
 				"<f1>":       "help",
 			},

handlers/event.go

@@ -20,24 +20,26 @@ var timer *time.Timer
 // these action names can then be used to bind them to specific keys
 // in the Config.
 var actionMap = map[string]func(*context.AppContext){
-	"space":          actionSpace,
-	"backspace":      actionBackSpace,
-	"delete":         actionDelete,
-	"cursor-right":   actionMoveCursorRight,
-	"cursor-left":    actionMoveCursorLeft,
-	"send":           actionSend,
-	"quit":           actionQuit,
-	"mode-insert":    actionInsertMode,
-	"mode-command":   actionCommandMode,
-	"mode-search":    actionSearchMode,
-	"clear-input":    actionClearInput,
-	"channel-up":     actionMoveCursorUpChannels,
-	"channel-down":   actionMoveCursorDownChannels,
-	"channel-top":    actionMoveCursorTopChannels,
-	"channel-bottom": actionMoveCursorBottomChannels,
-	"chat-up":        actionScrollUpChat,
-	"chat-down":      actionScrollDownChat,
-	"help":           actionHelp,
+	"space":               actionSpace,
+	"backspace":           actionBackSpace,
+	"delete":              actionDelete,
+	"cursor-right":        actionMoveCursorRight,
+	"cursor-left":         actionMoveCursorLeft,
+	"send":                actionSend,
+	"quit":                actionQuit,
+	"mode-insert":         actionInsertMode,
+	"mode-command":        actionCommandMode,
+	"mode-search":         actionSearchMode,
+	"clear-input":         actionClearInput,
+	"channel-up":          actionMoveCursorUpChannels,
+	"channel-down":        actionMoveCursorDownChannels,
+	"channel-top":         actionMoveCursorTopChannels,
+	"channel-bottom":      actionMoveCursorBottomChannels,
+	"channel-search-next": actionSearchNextChannels,
+	"channel-search-prev": actionSearchPrevChannels,
+	"chat-up":             actionScrollUpChat,
+	"chat-down":           actionScrollDownChat,
+	"help":                actionHelp,
 }
 
 func RegisterEventHandlers(ctx *context.AppContext) {
@@ -326,6 +328,16 @@ func actionMoveCursorBottomChannels(ctx *context.AppContext) {
 	actionChangeChannel(ctx)
 }
 
+func actionSearchNextChannels(ctx *context.AppContext) {
+	ctx.View.Channels.SearchNext()
+	actionChangeChannel(ctx)
+}
+
+func actionSearchPrevChannels(ctx *context.AppContext) {
+	ctx.View.Channels.SearchPrev()
+	actionChangeChannel(ctx)
+}
+
 func actionChangeChannel(ctx *context.AppContext) {
 	// Clear messages from Chat pane
 	ctx.View.Chat.ClearMessages()

vendor/github.com/renstrom/fuzzysearch/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Peter Renström
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/github.com/renstrom/fuzzysearch/fuzzy/fuzzy.go

@@ -0,0 +1,167 @@
+// Fuzzy searching allows for flexibly matching a string with partial input,
+// useful for filtering data very quickly based on lightweight user input.
+package fuzzy
+
+import (
+	"unicode"
+	"unicode/utf8"
+)
+
+var noop = func(r rune) rune { return r }
+
+// Match returns true if source matches target using a fuzzy-searching
+// algorithm. Note that it doesn't implement Levenshtein distance (see
+// RankMatch instead), but rather a simplified version where there's no
+// approximation. The method will return true only if each character in the
+// source can be found in the target and occurs after the preceding matches.
+func Match(source, target string) bool {
+	return match(source, target, noop)
+}
+
+// MatchFold is a case-insensitive version of Match.
+func MatchFold(source, target string) bool {
+	return match(source, target, unicode.ToLower)
+}
+
+func match(source, target string, fn func(rune) rune) bool {
+	lenDiff := len(target) - len(source)
+
+	if lenDiff < 0 {
+		return false
+	}
+
+	if lenDiff == 0 && source == target {
+		return true
+	}
+
+Outer:
+	for _, r1 := range source {
+		for i, r2 := range target {
+			if fn(r1) == fn(r2) {
+				target = target[i+utf8.RuneLen(r2):]
+				continue Outer
+			}
+		}
+		return false
+	}
+
+	return true
+}
+
+// Find will return a list of strings in targets that fuzzy matches source.
+func Find(source string, targets []string) []string {
+	return find(source, targets, noop)
+}
+
+// FindFold is a case-insensitive version of Find.
+func FindFold(source string, targets []string) []string {
+	return find(source, targets, unicode.ToLower)
+}
+
+func find(source string, targets []string, fn func(rune) rune) []string {
+	var matches []string
+
+	for _, target := range targets {
+		if match(source, target, fn) {
+			matches = append(matches, target)
+		}
+	}
+
+	return matches
+}
+
+// RankMatch is similar to Match except it will measure the Levenshtein
+// distance between the source and the target and return its result. If there
+// was no match, it will return -1.
+// Given the requirements of match, RankMatch only needs to perform a subset of
+// the Levenshtein calculation, only deletions need be considered, required
+// additions and substitutions would fail the match test.
+func RankMatch(source, target string) int {
+	return rank(source, target, noop)
+}
+
+// RankMatchFold is a case-insensitive version of RankMatch.
+func RankMatchFold(source, target string) int {
+	return rank(source, target, unicode.ToLower)
+}
+
+func rank(source, target string, fn func(rune) rune) int {
+	lenDiff := len(target) - len(source)
+
+	if lenDiff < 0 {
+		return -1
+	}
+
+	if lenDiff == 0 && source == target {
+		return 0
+	}
+
+	runeDiff := 0
+
+Outer:
+	for _, r1 := range source {
+		for i, r2 := range target {
+			if fn(r1) == fn(r2) {
+				target = target[i+utf8.RuneLen(r2):]
+				continue Outer
+			} else {
+				runeDiff++
+			}
+		}
+		return -1
+	}
+
+	// Count up remaining char
+	for len(target) > 0 {
+		target = target[utf8.RuneLen(rune(target[0])):]
+		runeDiff++
+	}
+
+	return runeDiff
+}
+
+// RankFind is similar to Find, except it will also rank all matches using
+// Levenshtein distance.
+func RankFind(source string, targets []string) Ranks {
+	var r Ranks
+	for _, target := range find(source, targets, noop) {
+		distance := LevenshteinDistance(source, target)
+		r = append(r, Rank{source, target, distance})
+	}
+	return r
+}
+
+// RankFindFold is a case-insensitive version of RankFind.
+func RankFindFold(source string, targets []string) Ranks {
+	var r Ranks
+	for _, target := range find(source, targets, unicode.ToLower) {
+		distance := LevenshteinDistance(source, target)
+		r = append(r, Rank{source, target, distance})
+	}
+	return r
+}
+
+type Rank struct {
+	// Source is used as the source for matching.
+	Source string
+
+	// Target is the word matched against.
+	Target string
+
+	// Distance is the Levenshtein distance between Source and Target.
+	Distance int
+}
+
+type Ranks []Rank
+
+func (r Ranks) Len() int {
+	return len(r)
+}
+
+func (r Ranks) Swap(i, j int) {
+	r[i], r[j] = r[j], r[i]
+}
+
+func (r Ranks) Less(i, j int) bool {
+	return r[i].Distance < r[j].Distance
+}

vendor/github.com/renstrom/fuzzysearch/fuzzy/levenshtein.go

@@ -0,0 +1,43 @@
+package fuzzy
+
+// LevenshteinDistance measures the difference between two strings.
+// The Levenshtein distance between two words is the minimum number of
+// single-character edits (i.e. insertions, deletions or substitutions)
+// required to change one word into the other.
+//
+// This implemention is optimized to use O(min(m,n)) space and is based on the
+// optimized C version found here:
+// http://en.wikibooks.org/wiki/Algorithm_implementation/Strings/Levenshtein_distance#C
+func LevenshteinDistance(s, t string) int {
+	r1, r2 := []rune(s), []rune(t)
+	column := make([]int, len(r1)+1)
+
+	for y := 1; y <= len(r1); y++ {
+		column[y] = y
+	}
+
+	for x := 1; x <= len(r2); x++ {
+		column[0] = x
+
+		for y, lastDiag := 1, x-1; y <= len(r1); y++ {
+			oldDiag := column[y]
+			cost := 0
+			if r1[y-1] != r2[x-1] {
+				cost = 1
+			}
+			column[y] = min(column[y]+1, column[y-1]+1, lastDiag+cost)
+			lastDiag = oldDiag
+		}
+	}
+
+	return column[len(r1)]
+}
+
+func min(a, b, c int) int {
+	if a < b && a < c {
+		return a
+	} else if b < c {
+		return b
+	}
+	return c
+}

vendor/vendor.json

@@ -90,6 +90,12 @@
 			"revision": "aa4a75b1c20a2b03751b1a9f7e41d58bd6f71c43",
 			"revisionTime": "2017-11-04T16:23:16Z"
 		},
+		{
+			"checksumSHA1": "DF3jZEw4lCq/SEaC7DIl/R+7S70=",
+			"path": "github.com/renstrom/fuzzysearch/fuzzy",
+			"revision": "2d205ac6ec17a839a94bdbfd16d2fa6c6dada2e0",
+			"revisionTime": "2016-03-31T20:48:55Z"
+		},
 		{
 			"path": "go/ast",
 			"revision": ""