package parse

import (
	"strings"
	"testing"
)

func sp(s string) *string { return &s }

func TestParse(t *testing.T) {
	tests := []struct {
		name       string
		input      string
		wantBody   string
		wantGlyph  string
		wantTitle  *string
		wantDesc   *string
		wantTime   *string
		wantTags   []string
		wantCard   *string
		wantPin    bool
		wantQuery  bool
		wantFilter []string
		wantErrSub string
	}{
		// Kind prefixes
		{"plain note", "hello world", "hello world", "note", nil, nil, nil, nil, nil, false, false, nil, ""},
		{"dash todo", "- deploy nginx", "deploy nginx", "todo", nil, nil, nil, nil, nil, false, false, nil, ""},
		{"dash todo requires space", "-deploy", "-deploy", "note", nil, nil, nil, nil, nil, false, false, nil, ""},
		{"event prefix", "@14:00 dentist", "dentist", "event", nil, nil, sp("14:00"), nil, nil, false, false, nil, ""},
		{"event no body", "@9:30", "", "event", nil, nil, sp("9:30"), nil, nil, false, false, nil, "empty body"},
		{"reminder prefix", "!15:00 call dentist", "call dentist", "reminder", nil, nil, sp("15:00"), nil, nil, false, false, nil, ""},
		{"reminder no body", "!9:30", "", "reminder", nil, nil, sp("9:30"), nil, nil, false, false, nil, "empty body"},

		// Event/reminder with invalid time — @ stays as body token, ! stays as body token
		{"at-sign not time", "@nottime hello", "@nottime hello", "note", nil, nil, nil, nil, nil, false, false, nil, ""},
		{"bang not time", "!nottime hello", "!nottime hello", "note", nil, nil, nil, nil, nil, false, false, nil, ""},

		// Escape prefix
		{"escape dash", `\- this is not a todo`, "- this is not a todo", "note", nil, nil, nil, nil, nil, false, false, nil, ""},
		{"escape at", `\@14:00 not event`, "not event", "note", nil, nil, sp("14:00"), nil, nil, false, false, nil, ""},
		{"escape plain", `\hello`, "hello", "note", nil, nil, nil, nil, nil, false, false, nil, ""},

		// Query mode
		{"query basic", "? proxy config", "proxy config", "", nil, nil, nil, nil, nil, false, true, nil, ""},
		{"query with tags", "? proxy config #ops #infra", "proxy config", "", nil, nil, nil, nil, nil, false, true, []string{"ops", "infra"}, ""},
		{"query tags only", "? #ops", "", "", nil, nil, nil, nil, nil, false, true, []string{"ops"}, ""},

		// Inline time anchor
		{"inline time", "meeting @14:00", "meeting", "note", nil, nil, sp("14:00"), nil, nil, false, false, nil, ""},
		{"todo due time", "- buy milk @9:30", "buy milk", "todo", nil, nil, sp("9:30"), nil, nil, false, false, nil, ""},
		{"invalid hours stays as body", "meeting @25:00", "meeting @25:00", "note", nil, nil, nil, nil, nil, false, false, nil, ""},
		{"invalid minutes stays as body", "meeting @14:60", "meeting @14:60", "note", nil, nil, nil, nil, nil, false, false, nil, ""},

		// Tags (lowercased)
		{"single tag", "deploy #Ops", "deploy", "note", nil, nil, nil, []string{"ops"}, nil, false, false, nil, ""},
		{"multiple tags", "deploy #ops #Infra", "deploy", "note", nil, nil, nil, []string{"ops", "infra"}, nil, false, false, nil, ""},
		{"duplicate tags", "deploy #ops #Ops", "deploy", "note", nil, nil, nil, []string{"ops"}, nil, false, false, nil, ""},
		{"tag with hyphen", "task #dev-ops", "task", "note", nil, nil, nil, []string{"dev-ops"}, nil, false, false, nil, ""},

		// Hash escape
		{"double hash escape", "use ##channel in slack", "use #channel in slack", "note", nil, nil, nil, nil, nil, false, false, nil, ""},
		{"double hash with tag", "use ##channel #ops", "use #channel", "note", nil, nil, nil, []string{"ops"}, nil, false, false, nil, ""},

		// Pin flag
		{"pin flag", "important thing !pin", "important thing", "note", nil, nil, nil, nil, nil, true, false, nil, ""},
		{"pin case insensitive", "important !Pin #work", "important", "note", nil, nil, nil, []string{"work"}, nil, true, false, nil, ""},
		{"pin with todo", "- urgent task !pin", "urgent task", "todo", nil, nil, nil, nil, nil, true, false, nil, ""},

		// !pin at start — not a reminder, flag is extracted
		{"bang pin only", "!pin important", "important", "note", nil, nil, nil, nil, nil, true, false, nil, ""},

		// Card suffix (kept for now)
		{"caret card", "trick #nginx ^card", "trick", "note", nil, nil, nil, []string{"nginx"}, sp("snippet"), false, false, nil, ""},
		{"caret c", "trick ^c", "trick", "note", nil, nil, nil, nil, sp("snippet"), false, false, nil, ""},
		{"caret template", "deploy ${host} ^template", "deploy ${host}", "note", nil, nil, nil, nil, sp("template"), false, false, nil, ""},
		{"invalid card type", "thing ^bogus", "", "", nil, nil, nil, nil, nil, false, false, nil, "invalid card type"},

		// Combined
		{"full todo", "- deploy nginx @15:00 #ops", "deploy nginx", "todo", nil, nil, sp("15:00"), []string{"ops"}, nil, false, false, nil, ""},
		{"full event", "@14:00 lunch with alex #personal", "lunch with alex", "event", nil, nil, sp("14:00"), []string{"personal"}, nil, false, false, nil, ""},
		{"full reminder", "!15:00 call dentist #health", "call dentist", "reminder", nil, nil, sp("15:00"), []string{"health"}, nil, false, false, nil, ""},

		// Title
		{"title with body", "|nginx trick\nproxy_pass trailing slash #ops", "proxy_pass trailing slash", "note", sp("nginx trick"), nil, nil, []string{"ops"}, nil, false, false, nil, ""},
		{"no title", "no pipe here #ops", "no pipe here", "note", nil, nil, nil, []string{"ops"}, nil, false, false, nil, ""},
		{"todo with title", "- |deploy staging\nrebuild docker #ops", "rebuild docker", "todo", sp("deploy staging"), nil, nil, []string{"ops"}, nil, false, false, nil, ""},
		{"title only", "|title only", "", "note", sp("title only"), nil, nil, nil, nil, false, false, nil, ""},
		{"title and desc", "|title // description #ops\nbody here", "body here", "note", sp("title"), sp("description"), nil, []string{"ops"}, nil, false, false, nil, ""},
		{"todo title desc", "- |deploy staging // rebuild and push #ops", "", "todo", sp("deploy staging"), sp("rebuild and push"), nil, []string{"ops"}, nil, false, false, nil, ""},

		// Description without title
		{"leading desc", "// leading desc\nbody content", "body content", "note", nil, sp("leading desc"), nil, nil, nil, false, false, nil, ""},
		{"inline desc", "body text // inline desc", "body text", "note", nil, sp("inline desc"), nil, nil, nil, false, false, nil, ""},
		{"url no split", "http://example.com // should not split", "http://example.com // should not split", "note", nil, nil, nil, nil, nil, false, false, nil, ""},

		// Multiline body preserves newlines
		{"multiline body", "hello\nworld", "hello\nworld", "note", nil, nil, nil, nil, nil, false, false, nil, ""},
		{"multiline with tags", "line one #ops\nline two", "line one\nline two", "note", nil, nil, nil, []string{"ops"}, nil, false, false, nil, ""},
		{"title multiline body", "|my title\nfirst line\nsecond line", "first line\nsecond line", "note", sp("my title"), nil, nil, nil, nil, false, false, nil, ""},

		// Edge cases
		{"empty input", "", "", "", nil, nil, nil, nil, nil, false, false, nil, "empty"},
		{"only glyph", "-", "", "", nil, nil, nil, nil, nil, false, false, nil, "empty body"},
		{"only modifiers", "#ops @14:00", "", "", nil, nil, nil, nil, nil, false, false, nil, "empty body"},
		{"whitespace only", "   ", "", "", nil, nil, nil, nil, nil, false, false, nil, "empty"},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got, err := Parse(tt.input)

			if tt.wantErrSub != "" {
				if err == nil {
					t.Fatalf("expected error containing %q, got nil", tt.wantErrSub)
				}
				if !strings.Contains(err.Error(), tt.wantErrSub) {
					t.Fatalf("expected error containing %q, got %q", tt.wantErrSub, err.Error())
				}
				return
			}

			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}

			if got.Body != tt.wantBody {
				t.Errorf("body: got %q, want %q", got.Body, tt.wantBody)
			}
			if got.Glyph != tt.wantGlyph {
				t.Errorf("glyph: got %q, want %q", got.Glyph, tt.wantGlyph)
			}
			if !ptrEq(got.Title, tt.wantTitle) {
				t.Errorf("title: got %v, want %v", strPtr(got.Title), strPtr(tt.wantTitle))
			}
			if !ptrEq(got.Description, tt.wantDesc) {
				t.Errorf("description: got %v, want %v", strPtr(got.Description), strPtr(tt.wantDesc))
			}
			if !ptrEq(got.TimeAnchor, tt.wantTime) {
				t.Errorf("time_anchor: got %v, want %v", strPtr(got.TimeAnchor), strPtr(tt.wantTime))
			}
			if !tagsEq(got.Tags, tt.wantTags) {
				t.Errorf("tags: got %v, want %v", got.Tags, tt.wantTags)
			}
			if !ptrEq(got.CardSuffix, tt.wantCard) {
				t.Errorf("card_suffix: got %v, want %v", strPtr(got.CardSuffix), strPtr(tt.wantCard))
			}
			if got.Pin != tt.wantPin {
				t.Errorf("pin: got %v, want %v", got.Pin, tt.wantPin)
			}
			if got.Query != tt.wantQuery {
				t.Errorf("query: got %v, want %v", got.Query, tt.wantQuery)
			}
			if !tagsEq(got.FilterTags, tt.wantFilter) {
				t.Errorf("filter_tags: got %v, want %v", got.FilterTags, tt.wantFilter)
			}
		})
	}
}

func ptrEq(a, b *string) bool {
	if a == nil && b == nil {
		return true
	}
	if a == nil || b == nil {
		return false
	}
	return *a == *b
}

func strPtr(p *string) string {
	if p == nil {
		return "<nil>"
	}
	return *p
}

func tagsEq(a, b []string) bool {
	if len(a) == 0 && len(b) == 0 {
		return true
	}
	if len(a) != len(b) {
		return false
	}
	for i := range a {
		if a[i] != b[i] {
			return false
		}
	}
	return true
}