Work on merging completion tree with parse tree

tools/cli/completion.go

@@ -0,0 +1,154 @@
+// License: GPLv3 Copyright: 2022, Kovid Goyal, <kovid at kovidgoyal.net>
+
+package cli
+
+import (
+	"fmt"
+	"path/filepath"
+	"strings"
+
+	"kitty/tools/utils"
+	"kitty/tools/wcswidth"
+)
+
+var _ = fmt.Print
+
+type Match struct {
+	Word        string `json:"word,omitempty"`
+	Description string `json:"description,omitempty"`
+}
+
+type MatchGroup struct {
+	Title           string   `json:"title,omitempty"`
+	NoTrailingSpace bool     `json:"no_trailing_space,omitempty"`
+	IsFiles         bool     `json:"is_files,omitempty"`
+	Matches         []*Match `json:"matches,omitempty"`
+}
+
+func (self *MatchGroup) remove_common_prefix() string {
+	if self.IsFiles {
+		if len(self.Matches) > 1 {
+			lcp := self.longest_common_prefix()
+			if strings.Contains(lcp, utils.Sep) {
+				lcp = strings.TrimRight(filepath.Dir(lcp), utils.Sep) + utils.Sep
+				self.remove_prefix_from_all_matches(lcp)
+				return lcp
+			}
+		}
+	} else if len(self.Matches) > 1 && strings.HasPrefix(self.Matches[0].Word, "--") && strings.Contains(self.Matches[0].Word, "=") {
+		lcp, _, _ := utils.Cut(self.longest_common_prefix(), "=")
+		lcp += "="
+		if len(lcp) > 3 {
+			self.remove_prefix_from_all_matches(lcp)
+			return lcp
+		}
+	}
+	return ""
+}
+
+func (self *MatchGroup) add_match(word string, description ...string) *Match {
+	ans := Match{Word: word, Description: strings.Join(description, " ")}
+	self.Matches = append(self.Matches, &ans)
+	return &ans
+}
+
+func (self *MatchGroup) add_prefix_to_all_matches(prefix string) {
+	for _, m := range self.Matches {
+		m.Word = prefix + m.Word
+	}
+}
+
+func (self *MatchGroup) remove_prefix_from_all_matches(prefix string) {
+	for _, m := range self.Matches {
+		m.Word = m.Word[len(prefix):]
+	}
+}
+
+func (self *MatchGroup) has_descriptions() bool {
+	for _, m := range self.Matches {
+		if m.Description != "" {
+			return true
+		}
+	}
+	return false
+}
+
+func (self *MatchGroup) max_visual_word_length(limit int) int {
+	ans := 0
+	for _, m := range self.Matches {
+		if q := wcswidth.Stringwidth(m.Word); q > ans {
+			ans = q
+			if ans > limit {
+				return limit
+			}
+		}
+	}
+	return ans
+}
+
+func (self *MatchGroup) longest_common_prefix() string {
+	limit := len(self.Matches)
+	i := 0
+	return utils.LongestCommon(func() (string, bool) {
+		if i < limit {
+			i++
+			return self.Matches[i-1].Word, false
+		}
+		return "", true
+	}, true)
+}
+
+type Delegate struct {
+	NumToRemove int    `json:"num_to_remove,omitempty"`
+	Command     string `json:"command,omitempty"`
+}
+
+type Completions struct {
+	Groups   []*MatchGroup `json:"groups,omitempty"`
+	Delegate Delegate      `json:"delegate,omitempty"`
+
+	current_cmd                *Command
+	all_words                  []string // all words passed to parse_args()
+	current_word_idx           int      // index of current word in all_words
+	current_word_idx_in_parent int      // index of current word in parents command line 1 for first word after parent
+
+	split_on_equals bool // true if the cmdline is split on = (BASH does this because readline does this)
+}
+
+func (self *Completions) add_prefix_to_all_matches(prefix string) {
+	for _, mg := range self.Groups {
+		mg.add_prefix_to_all_matches(prefix)
+	}
+}
+
+func (self *Completions) add_match_group(title string) *MatchGroup {
+	for _, q := range self.Groups {
+		if q.Title == title {
+			return q
+		}
+	}
+	ans := MatchGroup{Title: title, Matches: make([]*Match, 0, 8)}
+	self.Groups = append(self.Groups, &ans)
+	return &ans
+}
+
+type CompletionFunc func(completions *Completions, word string, arg_num int)
+
+func NamesCompleter(title string, names ...string) CompletionFunc {
+	return func(completions *Completions, word string, arg_num int) {
+		mg := completions.add_match_group(title)
+		for _, q := range names {
+			if strings.HasPrefix(q, word) {
+				mg.add_match(q)
+			}
+		}
+	}
+}
+
+func ChainCompleters(completers ...CompletionFunc) CompletionFunc {
+	return func(completions *Completions, word string, arg_num int) {
+		for _, f := range completers {
+			f(completions, word, arg_num)
+		}
+	}
+}