package dockerimg

import (
	"cmp"
	"context"
	"flag"
	"io/fs"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"testing/fstest"

	gcmp "github.com/google/go-cmp/cmp"
	"sketch.dev/httprr"
	"sketch.dev/llm/ant"
)

var flagRewriteWant = flag.Bool("rewritewant", false, "rewrite the dockerfiles we want from the model")

func TestCreateDockerfile(t *testing.T) {
	ctx := context.Background()

	tests := []struct {
		name string
		fsys fs.FS
	}{
		{
			name: "Basic repo with README",
			fsys: fstest.MapFS{
				"README.md": &fstest.MapFile{Data: []byte("# Test Project\nA Go project for testing.")},
			},
		},
		{
			// TODO: this looks bogus.
			name: "Repo with README and workflow",
			fsys: fstest.MapFS{
				"README.md": &fstest.MapFile{Data: []byte("# Test Project\nA Go project for testing.")},
				".github/workflows/test.yml": &fstest.MapFile{Data: []byte(`name: Test
on: [push]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: actions/setup-node@v3
        with:
          node-version: '18'
      - name: Install and activate corepack
        run: |
          npm install -g corepack
          corepack enable
      - run: go test ./...`)},
			},
		},
		{
			name: "mention a devtool in the readme",
			fsys: fstest.MapFS{
				"readme.md": &fstest.MapFile{Data: []byte("# Test Project\nYou must install `dot` to run the tests.")},
			},
		},
		{
			name: "empty repo",
			fsys: fstest.MapFS{
				"main.go": &fstest.MapFile{Data: []byte("package main\n\nfunc main() {}")},
			},
		},
		{
			name: "python misery",
			fsys: fstest.MapFS{
				"README.md": &fstest.MapFile{Data: []byte("# Our amazing repo\n\nTo use this project you need python 3.11 and the dvc tool")},
			},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			basePath := "testdata/" + strings.ToLower(strings.Replace(t.Name(), "/", "_", -1))
			rrPath := basePath + ".httprr"
			rr, err := httprr.Open(rrPath, http.DefaultTransport)
			if err != nil && !os.IsNotExist(err) {
				t.Fatal(err)
			}
			rr.ScrubReq(func(req *http.Request) error {
				req.Header.Del("x-api-key")
				return nil
			})
			initFiles, err := readInitFiles(tt.fsys)
			if err != nil {
				t.Fatal(err)
			}
			apiKey := cmp.Or(os.Getenv("OUTER_SKETCH_MODEL_API_KEY"), os.Getenv("ANTHROPIC_API_KEY"))
			srv := &ant.Service{
				APIKey: apiKey,
				HTTPC:  rr.Client(),
			}
			result, err := createDockerfile(ctx, srv, initFiles, "", false)
			if err != nil {
				t.Fatal(err)
			}

			wantPath := basePath + ".dockerfile"

			if *flagRewriteWant {
				if err := os.WriteFile(wantPath, []byte(result), 0o666); err != nil {
					t.Fatal(err)
				}
				return
			}

			wantBytes, err := os.ReadFile(wantPath)
			if err != nil {
				t.Fatal(err)
			}
			want := string(wantBytes)
			if diff := gcmp.Diff(want, result); diff != "" {
				t.Errorf("dockerfile does not match. got:\n----\n%s\n----\n\ndiff: %s", result, diff)
			}
		})
	}
}

func TestReadInitFiles(t *testing.T) {
	testFS := fstest.MapFS{
		"README.md":                  &fstest.MapFile{Data: []byte("# Test Repo")},
		".github/workflows/test.yml": &fstest.MapFile{Data: []byte("name: Test Workflow")},
		"main.go":                    &fstest.MapFile{Data: []byte("package main")},
		".git/HEAD":                  &fstest.MapFile{Data: []byte("ref: refs/heads/main")},
		"random/README.md":           &fstest.MapFile{Data: []byte("ignore me")},
	}

	files, err := readInitFiles(testFS)
	if err != nil {
		t.Fatalf("readInitFiles failed: %v", err)
	}

	// Should have 2 files: README.md and .github/workflows/test.yml
	if len(files) != 2 {
		t.Errorf("Expected 2 files, got %d", len(files))
	}

	if content, ok := files["README.md"]; !ok {
		t.Error("README.md not found")
	} else if content != "# Test Repo" {
		t.Errorf("README.md has incorrect content: %q", content)
	}

	if content, ok := files[".github/workflows/test.yml"]; !ok {
		t.Error(".github/workflows/test.yml not found")
	} else if content != "name: Test Workflow" {
		t.Errorf("Workflow file has incorrect content: %q", content)
	}

	if _, ok := files["main.go"]; ok {
		t.Error("main.go should not be included")
	}

	if _, ok := files[".git/HEAD"]; ok {
		t.Error(".git/HEAD should not be included")
	}
}

func TestReadInitFilesWithSubdir(t *testing.T) {
	// Create a file system with files in a subdirectory
	testFS := fstest.MapFS{
		"subdir/README.md":                  &fstest.MapFile{Data: []byte("# Test Repo")},
		"subdir/.github/workflows/test.yml": &fstest.MapFile{Data: []byte("name: Test Workflow")},
		"subdir/main.go":                    &fstest.MapFile{Data: []byte("package main")},
	}

	// Use fs.Sub to get a sub-filesystem
	subFS, err := fs.Sub(testFS, "subdir")
	if err != nil {
		t.Fatalf("fs.Sub failed: %v", err)
	}

	files, err := readInitFiles(subFS)
	if err != nil {
		t.Fatalf("readInitFiles failed: %v", err)
	}

	// Should have 2 files: README.md and .github/workflows/test.yml
	if len(files) != 2 {
		t.Errorf("Expected 2 files, got %d", len(files))
	}

	// Verify README.md was found
	if content, ok := files["README.md"]; !ok {
		t.Error("README.md not found")
	} else if content != "# Test Repo" {
		t.Errorf("README.md has incorrect content: %q", content)
	}

	// Verify workflow file was found
	if content, ok := files[".github/workflows/test.yml"]; !ok {
		t.Error(".github/workflows/test.yml not found")
	} else if content != "name: Test Workflow" {
		t.Errorf("Workflow file has incorrect content: %q", content)
	}
}

// TestDockerHashIsPushed ensures that any changes made to the
// dockerfile template have been pushed to the default image.
func TestDockerHashIsPushed(t *testing.T) {
	name, _, tag := DefaultImage()

	if err := checkTagExists(tag); err != nil {
		if strings.Contains(err.Error(), "not found") {
			t.Fatalf(`Currently released docker image %s does not match dockerfileCustomTmpl.

Inspecting the docker image shows the current hash of dockerfileBase is %s,
but it is not published in the GitHub container registry.

This means the template constants in createdockerfile.go have been
edited (e.g. dockerfileBase changed), but a new version
of the public default docker image has not been built and pushed.

To do so:

	go run ./dockerimg/pushdockerimg.go

`, name, tag)
		} else {
			t.Fatalf("checkTagExists: %v", err)
		}
	}
}

func TestGetHostGoCacheDirs(t *testing.T) {
	ctx := context.Background()

	// Test getHostGoCacheDir
	goCacheDir, err := getHostGoCacheDir(ctx)
	if err != nil {
		t.Fatalf("getHostGoCacheDir failed: %v", err)
	}
	if goCacheDir == "" {
		t.Fatal("getHostGoCacheDir returned empty string")
	}
	t.Logf("GOCACHE: %s", goCacheDir)

	// Test getHostGoModCacheDir
	goModCacheDir, err := getHostGoModCacheDir(ctx)
	if err != nil {
		t.Fatalf("getHostGoModCacheDir failed: %v", err)
	}
	if goModCacheDir == "" {
		t.Fatal("getHostGoModCacheDir returned empty string")
	}
	t.Logf("GOMODCACHE: %s", goModCacheDir)

	// Both should be absolute paths
	if !filepath.IsAbs(goCacheDir) {
		t.Errorf("GOCACHE is not an absolute path: %s", goCacheDir)
	}
	if !filepath.IsAbs(goModCacheDir) {
		t.Errorf("GOMODCACHE is not an absolute path: %s", goModCacheDir)
	}
}

func TestPrioritizeDockerfiles(t *testing.T) {
	tests := []struct {
		name       string
		candidates []string
		want       string
	}{
		{
			name:       "empty list",
			candidates: []string{},
			want:       "",
		},
		{
			name:       "single dockerfile",
			candidates: []string{"/path/to/Dockerfile"},
			want:       "/path/to/Dockerfile",
		},
		{
			name:       "dockerfile.sketch preferred over dockerfile",
			candidates: []string{"/path/to/Dockerfile", "/path/to/Dockerfile.sketch"},
			want:       "/path/to/Dockerfile.sketch",
		},
		{
			name:       "dockerfile.sketch preferred regardless of order",
			candidates: []string{"/path/to/Dockerfile.dev", "/path/to/Dockerfile", "/path/to/Dockerfile.sketch"},
			want:       "/path/to/Dockerfile.sketch",
		},
		{
			name:       "dockerfile preferred over other variations",
			candidates: []string{"/path/to/Dockerfile.dev", "/path/to/Dockerfile", "/path/to/Dockerfile.prod"},
			want:       "/path/to/Dockerfile",
		},
		{
			name:       "case insensitive dockerfile.sketch",
			candidates: []string{"/path/to/dockerfile", "/path/to/dockerfile.sketch"},
			want:       "/path/to/dockerfile.sketch",
		},
		{
			name:       "case insensitive dockerfile",
			candidates: []string{"/path/to/dockerfile.dev", "/path/to/dockerfile"},
			want:       "/path/to/dockerfile",
		},
		{
			name:       "first candidate when no priority matches",
			candidates: []string{"/path/to/Dockerfile.dev", "/path/to/Dockerfile.prod"},
			want:       "/path/to/Dockerfile.dev",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := prioritizeDockerfiles(tt.candidates)
			if got != tt.want {
				t.Errorf("prioritizeDockerfiles() = %v, want %v", got, tt.want)
			}
		})
	}
}

func TestFindDirDockerfilesIntegration(t *testing.T) {
	// Create a temporary directory structure for testing
	tmpDir, err := os.MkdirTemp("", "dockerfiles-test-*")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(tmpDir)

	// Create test files
	testFiles := []string{
		"Dockerfile",
		"Dockerfile.sketch",
		"Dockerfile.dev",
		"dockerfile.prod", // lowercase
		"README.md",       // should be ignored
	}

	for _, file := range testFiles {
		path := filepath.Join(tmpDir, file)
		if err := os.WriteFile(path, []byte("# test"), 0o644); err != nil {
			t.Fatal(err)
		}
	}

	// Test findDirDockerfiles
	candidates, err := findDirDockerfiles(tmpDir)
	if err != nil {
		t.Fatal(err)
	}

	// Should find all Dockerfile* files but not README.md
	expectedCount := 4
	if len(candidates) != expectedCount {
		t.Errorf("findDirDockerfiles() found %d files, want %d", len(candidates), expectedCount)
	}

	// Test prioritization
	prioritized := prioritizeDockerfiles(candidates)
	expectedPriority := filepath.Join(tmpDir, "Dockerfile.sketch")
	if prioritized != expectedPriority {
		t.Errorf("prioritizeDockerfiles() = %v, want %v", prioritized, expectedPriority)
	}

	// Test with only Dockerfile (no Dockerfile.sketch)
	os.Remove(filepath.Join(tmpDir, "Dockerfile.sketch"))
	candidates, err = findDirDockerfiles(tmpDir)
	if err != nil {
		t.Fatal(err)
	}
	prioritized = prioritizeDockerfiles(candidates)
	expectedPriority = filepath.Join(tmpDir, "Dockerfile")
	if prioritized != expectedPriority {
		t.Errorf("prioritizeDockerfiles() without sketch = %v, want %v", prioritized, expectedPriority)
	}
}

func TestFindRepoDockerfiles(t *testing.T) {
	// Create a temporary directory structure that simulates a git repo
	tmpDir, err := os.MkdirTemp("", "repo-test-*")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(tmpDir)

	// Create subdirectories
	subDir := filepath.Join(tmpDir, "subdir")
	if err := os.MkdirAll(subDir, 0o755); err != nil {
		t.Fatal(err)
	}

	// Create Dockerfile in subdirectory
	subDockerfile := filepath.Join(subDir, "Dockerfile")
	if err := os.WriteFile(subDockerfile, []byte("FROM ubuntu"), 0o644); err != nil {
		t.Fatal(err)
	}

	// Create Dockerfile.sketch in parent directory
	rootSketchDockerfile := filepath.Join(tmpDir, "Dockerfile.sketch")
	if err := os.WriteFile(rootSketchDockerfile, []byte("FROM alpine"), 0o644); err != nil {
		t.Fatal(err)
	}

	// Test: when called from subdirectory, should find subdirectory Dockerfile first
	candidates, err := findRepoDockerfiles(subDir, tmpDir)
	if err != nil {
		t.Fatal(err)
	}

	if len(candidates) == 0 {
		t.Fatal("expected to find at least one dockerfile")
	}

	// Should find the Dockerfile in the subdirectory
	if len(candidates) != 1 || candidates[0] != subDockerfile {
		t.Errorf("expected to find %s, but got %v", subDockerfile, candidates)
	}

	// Test: when called from root with no subdirectory dockerfile, should find root dockerfile
	os.Remove(subDockerfile) // Remove subdirectory dockerfile
	candidates, err = findRepoDockerfiles(tmpDir, tmpDir)
	if err != nil {
		t.Fatal(err)
	}

	if len(candidates) != 1 || candidates[0] != rootSketchDockerfile {
		t.Errorf("expected to find %s, but got %v", rootSketchDockerfile, candidates)
	}

	// Test prioritization: create both Dockerfile and Dockerfile.sketch in same directory
	rootDockerfile := filepath.Join(tmpDir, "Dockerfile")
	if err := os.WriteFile(rootDockerfile, []byte("FROM debian"), 0o644); err != nil {
		t.Fatal(err)
	}

	candidates, err = findRepoDockerfiles(tmpDir, tmpDir)
	if err != nil {
		t.Fatal(err)
	}

	if len(candidates) != 2 {
		t.Errorf("expected to find 2 dockerfiles, but got %d", len(candidates))
	}

	// Test that prioritization works correctly
	prioritized := prioritizeDockerfiles(candidates)
	if prioritized != rootSketchDockerfile {
		t.Errorf("expected Dockerfile.sketch to be prioritized, but got %s", prioritized)
	}
}

// TestDockerfileSketchImageReuse tests that Docker images built from Dockerfile.sketch
// are properly reused when the Dockerfile content hasn't changed.
func TestDockerfileSketchImageReuse(t *testing.T) {
	// Create a temporary directory for the test repo
	tmpDir := t.TempDir()

	// Create a simple Dockerfile.sketch
	dockerfileContent := `FROM ubuntu:24.04
LABEL test=true
CMD ["echo", "hello"]
`
	dockerfilePath := filepath.Join(tmpDir, "Dockerfile.sketch")
	err := os.WriteFile(dockerfilePath, []byte(dockerfileContent), 0o644)
	if err != nil {
		t.Fatalf("Failed to write Dockerfile.sketch: %v", err)
	}

	// Test that hashInitFiles produces consistent results
	initFiles := map[string]string{
		dockerfilePath: dockerfileContent,
	}
	hash1 := hashInitFiles(initFiles)
	hash2 := hashInitFiles(initFiles)

	if hash1 != hash2 {
		t.Errorf("hashInitFiles should be deterministic, got %s and %s", hash1, hash2)
	}

	// Test that hash changes when content changes
	modifiedFiles := map[string]string{
		dockerfilePath: dockerfileContent + "RUN echo modified\n",
	}
	hash3 := hashInitFiles(modifiedFiles)

	if hash1 == hash3 {
		t.Errorf("hashInitFiles should produce different hashes for different content, got %s for both", hash1)
	}

	t.Logf("Original hash: %s", hash1)
	t.Logf("Modified hash: %s", hash3)
}

// TestPrioritizeDockerfiles tests the Dockerfile prioritization logic
func TestDockerfileSketchPriority(t *testing.T) {
	tests := []struct {
		name       string
		candidates []string
		expected   string
	}{
		{
			name:       "dockerfile.sketch_wins_over_dockerfile",
			candidates: []string{"/path/Dockerfile", "/path/Dockerfile.sketch"},
			expected:   "/path/Dockerfile.sketch",
		},
		{
			name:       "dockerfile.sketch_case_insensitive",
			candidates: []string{"/path/dockerfile", "/path/dockerfile.sketch"},
			expected:   "/path/dockerfile.sketch",
		},
		{
			name:       "dockerfile_wins_over_variations",
			candidates: []string{"/path/Dockerfile.dev", "/path/Dockerfile"},
			expected:   "/path/Dockerfile",
		},
	}

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