package storage

import (
	"testing"
)

// ── chapterNumberFromKey ──────────────────────────────────────────────────────

func TestChapterNumberFromKey(t *testing.T) {
	cases := []struct {
		key  string
		want int
	}{
		// Standard four-segment key.
		{"my-novel/vol-0/1-50/chapter-1.md", 1},
		{"my-novel/vol-0/1-50/chapter-42.md", 42},
		{"my-novel/vol-0/51-100/chapter-99.md", 99},
		// Large chapter numbers.
		{"some-novel/vol-1/1001-1050/chapter-1024.md", 1024},
		// Nested deeper paths should still work (last segment used).
		{"a/b/c/d/chapter-7.md", 7},
		// Malformed / unexpected inputs — should return 0 without panicking.
		{"chapter-notanumber.md", 0},
		{"", 0},
		// No .md extension — TrimSuffix is a no-op; TrimPrefix still strips
		// "chapter-", so the number is parsed successfully.
		{"no-md-extension/chapter-5", 5},
		{"my-novel/vol-0/1-50/chapter-0.md", 0}, // 0 is invalid (chapters are 1-based)
		{"my-novel/vol-0/1-50/chapter--1.md", 0},
	}

	for _, tc := range cases {
		got := chapterNumberFromKey(tc.key)
		if got != tc.want {
			t.Errorf("chapterNumberFromKey(%q) = %d, want %d", tc.key, got, tc.want)
		}
	}
}

// ── splitChapterTitle ─────────────────────────────────────────────────────────

func TestSplitChapterTitle(t *testing.T) {
	cases := []struct {
		raw       string
		wantTitle string
		wantDate  string
	}{
		// No date — title is returned as-is.
		{"The Great Battle", "The Great Battle", ""},
		// Leading numeric index is stripped.
		{"42 The Great Battle", "The Great Battle", ""},
		// Relative date with plural unit.
		{"The Storm Arrives 3 days ago", "The Storm Arrives", "3 days ago"},
		// Singular unit.
		{"A New Hope 1 week ago", "A New Hope", "1 week ago"},
		// Minutes and seconds.
		{"Flash Fight 5 minutes ago", "Flash Fight", "5 minutes ago"},
		{"Quick Strike 30 seconds ago", "Quick Strike", "30 seconds ago"},
		// Months and years.
		{"Old Chapter 2 months ago", "Old Chapter", "2 months ago"},
		{"Ancient Story 1 year ago", "Ancient Story", "1 year ago"},
		// Leading index AND trailing date.
		{"5 The Final Chapter 2 hours ago", "The Final Chapter", "2 hours ago"},
		// Extra whitespace.
		{"  The Calm  ", "The Calm", ""},
		// Empty string.
		{"", "", ""},
	}

	for _, tc := range cases {
		title, date := splitChapterTitle(tc.raw)
		if title != tc.wantTitle || date != tc.wantDate {
			t.Errorf("splitChapterTitle(%q) = (%q, %q), want (%q, %q)",
				tc.raw, title, date, tc.wantTitle, tc.wantDate)
		}
	}
}