package handlers

import (
	"testing"

	"github.com/google/uuid"
)

// Pure-function tests for the embed handler helpers — no DB / HTTP
// fixtures required.

func TestExtractTrackIDFromURL(t *testing.T) {
	id := uuid.New()
	cases := []struct {
		name string
		url  string
		want uuid.UUID
		ok   bool
	}{
		{
			name: "happy path — frontend URL",
			url:  "https://veza.fr/tracks/" + id.String(),
			want: id,
			ok:   true,
		},
		{
			name: "with trailing slash",
			url:  "https://veza.fr/tracks/" + id.String() + "/",
			want: id,
			ok:   true,
		},
		{
			name: "with query string",
			url:  "https://veza.fr/tracks/" + id.String() + "?utm_source=twitter",
			want: id,
			ok:   true,
		},
		{
			name: "with hash fragment",
			url:  "https://veza.fr/tracks/" + id.String() + "#segment-2",
			want: id,
			ok:   true,
		},
		{
			name: "subpath under /tracks",
			url:  "https://veza.fr/tracks/" + id.String() + "/comments",
			want: id,
			ok:   true,
		},
		{
			name: "empty",
			url:  "",
			ok:   false,
		},
		{
			name: "no /tracks/ segment",
			url:  "https://veza.fr/playlists/abc",
			ok:   false,
		},
		{
			name: "non-uuid",
			url:  "https://veza.fr/tracks/not-a-uuid",
			ok:   false,
		},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			got, ok := extractTrackIDFromURL(tc.url)
			if ok != tc.ok {
				t.Fatalf("ok = %v, want %v", ok, tc.ok)
			}
			if ok && got != tc.want {
				t.Fatalf("id = %s, want %s", got, tc.want)
			}
		})
	}
}

func TestParseSafeInt(t *testing.T) {
	cases := []struct {
		in     string
		want   int
		wantOK bool
	}{
		{in: "0", want: 0, wantOK: true},
		{in: "480", want: 480, wantOK: true},
		{in: "1280", want: 1280, wantOK: true},
		{in: "100000", want: 100000, wantOK: true},
		// reject overflow attempts
		{in: "999999", wantOK: false},
		// reject non-digit
		{in: "480px", wantOK: false},
		{in: "-1", wantOK: false},
		{in: "", wantOK: true}, // empty parses to 0 (loop never runs)
	}
	for _, tc := range cases {
		t.Run(tc.in, func(t *testing.T) {
			n, err := parseSafeInt(tc.in)
			if (err == nil) != tc.wantOK {
				t.Fatalf("parseSafeInt(%q) ok=%v, want %v (err=%v)", tc.in, err == nil, tc.wantOK, err)
			}
			if tc.wantOK && n != tc.want {
				t.Fatalf("parseSafeInt(%q) = %d, want %d", tc.in, n, tc.want)
			}
		})
	}
}