package export

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func TestExport_WritesPageAndAssets(t *testing.T) {
	srcDir := t.TempDir()
	writeFile(t, srcDir, "010-intro.md", "---\ntitle: Intro\n---\n# Hallo\n")
	writeFile(t, srcDir, "020-hidden.md", "---\nskip: true\n---\n# Hidden\n")

	outDir := t.TempDir()
	if err := Export(srcDir, outDir, "deck.html"); err != nil {
		t.Fatalf("Export() error = %v", err)
	}

	tests := []struct {
		name           string
		path           string
		wantContains   string
		wantNotContain string
	}{
		{name: "html page", path: "deck.html", wantContains: "<h1>Hallo</h1>"},
		{name: "html excludes skipped slide", path: "deck.html", wantNotContain: "Hidden"},
		{name: "html excludes dev live-reload script", path: "deck.html", wantNotContain: "live-reload.js"},
		{name: "style.css copied", path: filepath.Join("vendor", "style.css"), wantContains: ":root"},
		{name: "chroma.css copied", path: filepath.Join("vendor", "chroma.css"), wantContains: ".chroma"},
		{name: "nav.js copied", path: filepath.Join("vendor", "nav.js"), wantContains: "mermaid.run"},
		{name: "vendor mermaid copied", path: filepath.Join("vendor", "mermaid.min.js")},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			data, err := os.ReadFile(filepath.Join(outDir, tt.path))
			if err != nil {
				t.Fatalf("reading %s: %v", tt.path, err)
			}
			if tt.wantContains != "" && !strings.Contains(string(data), tt.wantContains) {
				t.Errorf("%s does not contain %q", tt.path, tt.wantContains)
			}
			if tt.wantNotContain != "" && strings.Contains(string(data), tt.wantNotContain) {
				t.Errorf("%s unexpectedly contains %q", tt.path, tt.wantNotContain)
			}
			if len(data) == 0 {
				t.Errorf("%s is empty", tt.path)
			}
		})
	}

	if _, err := os.Stat(filepath.Join(outDir, "vendor", "live-reload.js")); !os.IsNotExist(err) {
		t.Errorf("live-reload.js should not be part of a static export, stat err = %v", err)
	}
}

func TestExport_CopiesUserAssets(t *testing.T) {
	srcDir := t.TempDir()
	writeFile(t, srcDir, "010-intro.md", "# Hallo\n![Bild](img/foto.png)\n")
	if err := os.MkdirAll(filepath.Join(srcDir, "img"), 0o755); err != nil {
		t.Fatalf("MkdirAll: %v", err)
	}
	writeFile(t, filepath.Join(srcDir, "img"), "foto.png", "fake-png-bytes")
	writeFile(t, srcDir, ".DS_Store", "should-not-be-copied")

	outDir := t.TempDir()
	if err := Export(srcDir, outDir, "deck.html"); err != nil {
		t.Fatalf("Export() error = %v", err)
	}

	data, err := os.ReadFile(filepath.Join(outDir, "img", "foto.png"))
	if err != nil {
		t.Fatalf("reading exported image: %v", err)
	}
	if string(data) != "fake-png-bytes" {
		t.Errorf("exported image content = %q, want %q", data, "fake-png-bytes")
	}

	if _, err := os.Stat(filepath.Join(outDir, ".DS_Store")); !os.IsNotExist(err) {
		t.Errorf(".DS_Store should not be exported, stat err = %v", err)
	}
}

func TestExport_InvalidSourceDir(t *testing.T) {
	outDir := t.TempDir()
	err := Export(filepath.Join(outDir, "does-not-exist"), outDir, "deck.html")
	if err == nil {
		t.Fatal("Export() error = nil, want error for missing source dir")
	}
}

func writeFile(t *testing.T, dir, name, content string) {
	t.Helper()
	if err := os.WriteFile(filepath.Join(dir, name), []byte(content), 0o644); err != nil {
		t.Fatalf("WriteFile(%s): %v", name, err)
	}
}