package tui

import (
	"testing"

	"github.com/lerko/nib/internal/db"
)

func TestTagTokenAtCursor(t *testing.T) {
	tests := []struct {
		name      string
		val       string
		cursor    int
		wantStart int
		wantEnd   int
		wantPfx   string
		wantOk    bool
	}{
		{"mid tag cursor after a", "hello #par world", 9, 6, 10, "pa", true},
		{"end of tag", "hello #par world", 10, 6, 10, "par", true},
		{"end of input", "hello #parenting", 16, 6, 16, "parenting", true},
		{"start of tag just hash", "hello # world", 7, 6, 7, "", true},
		{"not in tag", "hello world", 5, 0, 0, "", false},
		{"tag at start", "#ops stuff", 4, 0, 4, "ops", true},
		{"cursor at hash", "#ops", 1, 0, 4, "", true},
		{"multiple tags second", "hello #ops #inf", 15, 11, 15, "inf", true},
		{"empty string", "", 0, 0, 0, "", false},
		{"cursor past end", "#ops", 10, 0, 4, "ops", true},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			start, end, pfx, ok := tagTokenAtCursor(tt.val, tt.cursor)
			if ok != tt.wantOk {
				t.Fatalf("ok = %v, want %v", ok, tt.wantOk)
			}
			if !ok {
				return
			}
			if start != tt.wantStart || end != tt.wantEnd {
				t.Fatalf("range = [%d,%d), want [%d,%d)", start, end, tt.wantStart, tt.wantEnd)
			}
			if pfx != tt.wantPfx {
				t.Fatalf("prefix = %q, want %q", pfx, tt.wantPfx)
			}
		})
	}
}

func TestFilterTagSuggestions(t *testing.T) {
	tags := []db.TagCount{
		{Tag: "ops", Count: 5},
		{Tag: "ops-deploy", Count: 3},
		{Tag: "infra", Count: 2},
		{Tag: "ops-team", Count: 1},
	}

	tests := []struct {
		name   string
		prefix string
		want   []string
	}{
		{"empty prefix", "", nil},
		{"exact match excluded", "ops", []string{"ops-deploy", "ops-team"}},
		{"partial match", "op", []string{"ops", "ops-deploy", "ops-team"}},
		{"no match", "zzz", nil},
		{"case insensitive", "OP", []string{"ops", "ops-deploy", "ops-team"}},
		{"single match", "inf", []string{"infra"}},
		{"full match excluded", "infra", nil},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := filterTagSuggestions(tags, tt.prefix)
			if len(got) != len(tt.want) {
				t.Fatalf("got %v, want %v", got, tt.want)
			}
			for i := range got {
				if got[i] != tt.want[i] {
					t.Fatalf("got %v, want %v", got, tt.want)
				}
			}
		})
	}
}