package onstart

import (
	"context"
	"slices"
	"testing"
)

func TestAnalyzeCodebase(t *testing.T) {
	t.Run("Basic Analysis", func(t *testing.T) {
		// Test basic functionality with regular ASCII filenames
		codebase, err := AnalyzeCodebase(context.Background(), ".")
		if err != nil {
			t.Fatalf("AnalyzeCodebase failed: %v", err)
		}

		if codebase == nil {
			t.Fatal("Expected non-nil codebase")
		}

		if codebase.TotalFiles == 0 {
			t.Error("Expected some files to be analyzed")
		}

		if len(codebase.ExtensionCounts) == 0 {
			t.Error("Expected extension counts to be populated")
		}
	})

	t.Run("Non-ASCII Filenames", func(t *testing.T) {
		// Test with non-ASCII characters in filenames
		testdataPath := "./testdata"
		codebase, err := AnalyzeCodebase(context.Background(), testdataPath)
		if err != nil {
			t.Fatalf("AnalyzeCodebase failed with non-ASCII filenames: %v", err)
		}

		if codebase == nil {
			t.Fatal("Expected non-nil codebase")
		}

		// We expect 8 files in our testdata directory
		expectedFiles := 8
		if codebase.TotalFiles != expectedFiles {
			t.Errorf("Expected %d files, got %d", expectedFiles, codebase.TotalFiles)
		}

		// Verify extension counts include our non-ASCII files
		expectedExtensions := map[string]int{
			".go":            1, // 测试文件.go
			".js":            1, // café.js
			".py":            1, // русский.py
			".md":            3, // 🚀rocket.md, readme-español.md, claude-한국어.md
			".html":          1, // Übung.html
			"<no-extension>": 1, // Makefile-日本語
		}

		for ext, expectedCount := range expectedExtensions {
			actualCount, exists := codebase.ExtensionCounts[ext]
			if !exists {
				t.Errorf("Expected extension %s to be found", ext)
				continue
			}
			if actualCount != expectedCount {
				t.Errorf("Expected %d files with extension %s, got %d", expectedCount, ext, actualCount)
			}
		}

		// Verify file categorization works with non-ASCII filenames
		// Check build files
		if !slices.Contains(codebase.BuildFiles, "Makefile-日本語") {
			t.Error("Expected Makefile-日本語 to be categorized as a build file")
		}

		// Check documentation files
		if !slices.Contains(codebase.DocumentationFiles, "readme-español.md") {
			t.Error("Expected readme-español.md to be categorized as a documentation file")
		}

		// Check guidance files
		if !slices.Contains(codebase.GuidanceFiles, "subdir/claude.한국어.md") {
			t.Error("Expected subdir/claude.한국어.md to be categorized as a guidance file")
		}
	})
}

func TestCategorizeFile(t *testing.T) {
	t.Run("Non-ASCII Filenames", func(t *testing.T) {
		tests := []struct {
			name     string
			path     string
			expected string
		}{
			{"Chinese Go file", "测试文件.go", ""},
			{"French JS file", "café.js", ""},
			{"Russian Python file", "русский.py", ""},
			{"Emoji markdown file", "🚀rocket.md", ""},
			{"German HTML file", "Übung.html", ""},
			{"Japanese Makefile", "Makefile-日本語", "build"},
			{"Spanish README", "readme-español.md", "documentation"},
			{"Korean Claude file", "subdir/claude.한국어.md", "guidance"},
			// Test edge cases with Unicode normalization and combining characters
			{"Mixed Unicode file", "test中文🚀.txt", ""},
			{"Combining characters", "filé̂.go", ""}, // file with combining acute and circumflex accents
			{"Right-to-left script", "مرحبا.py", ""},  // Arabic "hello"
		}

		for _, tt := range tests {
			t.Run(tt.name, func(t *testing.T) {
				result := categorizeFile(tt.path)
				if result != tt.expected {
					t.Errorf("categorizeFile(%q) = %q, want %q", tt.path, result, tt.expected)
				}
			})
		}
	})
}

func TestTopExtensions(t *testing.T) {
	t.Run("With Non-ASCII Files", func(t *testing.T) {
		// Create a test codebase with known extension counts
		codebase := &Codebase{
			ExtensionCounts: map[string]int{
				".md":   5, // Most common
				".go":   3,
				".js":   2,
				".py":   1,
				".html": 1, // Least common
			},
			TotalFiles: 12,
		}

		topExt := codebase.TopExtensions()
		if len(topExt) != 5 {
			t.Errorf("Expected 5 top extensions, got %d", len(topExt))
		}

		// Check that extensions are sorted by count (descending)
		expected := []string{
			".md: 5 (42%)",
			".go: 3 (25%)",
			".js: 2 (17%)",
			".html: 1 (8%)",
			".py: 1 (8%)",
		}

		for i, expectedExt := range expected {
			if i >= len(topExt) {
				t.Errorf("Missing expected extension at index %d: %s", i, expectedExt)
				continue
			}
			if topExt[i] != expectedExt {
				t.Errorf("Expected extension %q at index %d, got %q", expectedExt, i, topExt[i])
			}
		}
	})
}