package mapping

import (
	"strings"
	"testing"

	sdk "code.gitea.io/sdk/gitea"
)

func TestIDInBodyReadsBothSpellings(t *testing.T) {
	cases := []struct {
		name string
		body string
		want string
	}{
		{"the spelling this tool writes", "<!-- kettle:id wire-sqlc -->\n\n## Summary\nx", "wire-sqlc"},
		// The whole reason the reader is wider than the writer.
		{"the spelling already in the tracker", "<!-- tea:id wire-sqlc -->\n\n## Summary\nx", "wire-sqlc"},
		{"indented and loosely spaced", "  <!--   tea:id   wire-sqlc   -->  \n", "wire-sqlc"},
		{"no marker at all", "## Summary\nx", ""},
		// A mangled comment falls back to the title rather than naming a file
		// after garbage.
		{"not a slug", "<!-- kettle:id Wire_SQLC -->\n", ""},
		{"not on a line of its own", "text <!-- kettle:id wire-sqlc -->\n", ""},
		{"the first valid marker wins", "<!-- tea:id first-one -->\n<!-- kettle:id second-one -->\n", "first-one"},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			if got := IDInBody(c.body); got != c.want {
				t.Errorf("IDInBody = %q, want %q", got, c.want)
			}
		})
	}
}

// An issue pushed under the old name is sitting in the tracker with its local
// file long since deleted — the marker is the only copy of its slug there is.
// It has to keep resolving, and it has to come back up in the new spelling.
func TestAnIssuePushedByTheOldNameStillResolves(t *testing.T) {
	const inTracker = "<!-- tea:id wire-sqlc-appclick -->\n\n## Summary\nПроводка sqlc.\n"

	id := IDInBody(inTracker)
	if id != "wire-sqlc-appclick" {
		t.Fatalf("IDInBody = %q — every issue pushed under the old name would be orphaned", id)
	}

	iss, _ := FromPayload(&sdk.Issue{Index: 42, Title: "Wire sqlc", Body: inTracker},
		id, tea, PayloadOptions{})
	if strings.Contains(iss.Body, "tea:id") {
		t.Errorf("the old marker reached the local copy: %q", iss.Body)
	}
	if iss.Body != "## Summary\nПроводка sqlc." {
		t.Errorf("body = %q", iss.Body)
	}

	// And the next push rewrites it into the current spelling, without ever
	// having two.
	up := ToCreate(iss, RequestOptions{}).Body
	if !strings.HasPrefix(up, "<!-- kettle:id wire-sqlc-appclick -->\n\n") {
		t.Errorf("the marker was not rewritten: %q", up)
	}
	if strings.Contains(up, "tea:id") {
		t.Errorf("both spellings went up: %q", up)
	}
	if n := strings.Count(up, ":id "); n != 1 {
		t.Errorf("%d markers in the body, want 1", n)
	}
}

func TestMarkersCannotAccumulate(t *testing.T) {
	body := "## Summary\nx"
	// Whatever it arrived with — one, the other, several — it goes up with one.
	messy := "<!-- tea:id old-one -->\n\n<!-- kettle:id other-one -->\n\n" + body
	got := WithIDMarker(messy, "real-one")

	if want := IDMarker("real-one") + "\n\n" + body; got != want {
		t.Errorf("got:\n%q\nwant:\n%q", got, want)
	}
	if got := WithIDMarker(got, "real-one"); strings.Count(got, "<!--") != 1 {
		t.Errorf("a second pass added one: %q", got)
	}
}

func TestStripIsTheExactInverseOfWith(t *testing.T) {
	bodies := []string{
		"## Summary\nx",
		"## Summary\nx\n\n## Acceptance criteria\n- [ ] один\n",
		"",
	}
	for _, b := range bodies {
		if got := StripIDMarker(WithIDMarker(b, "an-id")); got != b {
			t.Errorf("StripIDMarker(WithIDMarker(%q)) = %q", b, got)
		}
	}
}

// The common case — an issue filed in the web UI — costs nothing and is not
// reformatted.
func TestStripLeavesAnUnmarkedBodyByteForByte(t *testing.T) {
	body := "\n\n## Summary\nx\n\n\n"
	if got := StripIDMarker(body); got != body {
		t.Errorf("StripIDMarker rewrote a body with no marker in it: %q", got)
	}
}