package taskloop

import (
	"bufio"
	"fmt"
	"os"
	"path/filepath"
	"regexp"
	"sort"
	"strings"
	"testing"
)

const goPlanValidatorCommand = "go run ./apps/agent/cmd/agent task-loop validate-plan --workspace <workspace> <candidate-plan>"

var cutoverStaticOwnershipDocuments = []string{
	"agent-ops/skills/common/plan/SKILL.md",
	"agent-ops/skills/common/code-review/SKILL.md",
	"agent-ops/skills/project/orchestrate-agent-task-loop/SKILL.md",
	"agent-ops/rules/project/domain/testing/rules.md",
	"agent-ops/rules/project/rules.md",
}

var cutoverProductionRoots = []string{
	"agent-ops/skills/common",
	"agent-ops/skills/project",
	"agent-ops/rules",
}

func TestCutoverProductionOwnershipHasNoReferenceCallerOrStaticRouteTable(t *testing.T) {
	root := repoRoot(t)
	if err := validateCutoverProductionOwnership(root); err != nil {
		t.Fatal(err)
	}
}

func TestCutoverProductionOwnershipRejectsInjectedPythonCaller(t *testing.T) {
	root := t.TempDir()
	for _, relativeRoot := range cutoverProductionRoots {
		if err := os.MkdirAll(filepath.Join(root, relativeRoot), 0700); err != nil {
			t.Fatal(err)
		}
	}
	for _, relative := range cutoverStaticOwnershipDocuments {
		contents := ""
		if relative == "agent-ops/skills/common/plan/SKILL.md" || relative == "agent-ops/skills/common/code-review/SKILL.md" {
			contents = goPlanValidatorCommand
		}
		path := filepath.Join(root, relative)
		if err := os.MkdirAll(filepath.Dir(path), 0700); err != nil {
			t.Fatal(err)
		}
		if err := os.WriteFile(path, []byte(contents), 0600); err != nil {
			t.Fatal(err)
		}
	}
	relative := "agent-ops/skills/common/other/SKILL.md"
	path := filepath.Join(root, relative)
	if err := os.MkdirAll(filepath.Dir(path), 0700); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(path, []byte("python3 dispatch.py --validate-plan candidate\n"), 0600); err != nil {
		t.Fatal(err)
	}
	err := validateCutoverProductionOwnership(root)
	if err == nil || !strings.Contains(err.Error(), "matches") || !strings.Contains(err.Error(), ":1") {
		t.Fatalf("validateCutoverProductionOwnership error = %v", err)
	}
}

func TestCutoverNodeRemainsSharedRuntimeConsumer(t *testing.T) {
	root := repoRoot(t)
	patterns := []*regexp.Regexp{
		regexp.MustCompile(`agenttask\.NewManager\(`),
		regexp.MustCompile(`taskloop\.New\(`),
		regexp.MustCompile(`NewProvider\(`),
	}
	err := filepath.WalkDir(filepath.Join(root, "apps", "node"), func(path string, entry os.DirEntry, walkErr error) error {
		if walkErr != nil {
			return walkErr
		}
		if entry.IsDir() || !strings.HasSuffix(entry.Name(), ".go") || strings.HasSuffix(entry.Name(), "_test.go") {
			return nil
		}
		assertNoPatterns(t, path, patterns)
		return nil
	})
	if err != nil {
		t.Fatal(err)
	}
}

func assertNoPatterns(t *testing.T, path string, patterns []*regexp.Regexp) {
	t.Helper()
	file, err := os.Open(path)
	if err != nil {
		t.Fatal(err)
	}
	defer file.Close()
	scanner := bufio.NewScanner(file)
	line := 0
	for scanner.Scan() {
		line++
		for _, pattern := range patterns {
			if pattern.MatchString(scanner.Text()) {
				t.Fatalf("cutover ownership violation %s:%d matches %q", path, line, pattern.String())
			}
		}
	}
	if err := scanner.Err(); err != nil {
		t.Fatal(err)
	}
}

func validateCutoverProductionOwnership(root string) error {
	callerPatterns := []*regexp.Regexp{
		regexp.MustCompile(`dispatch\.py`),
		regexp.MustCompile(`python3 .*orchestrate-agent-task-loop`),
	}
	staticOwnershipPatterns := []*regexp.Regexp{
		regexp.MustCompile(`gpt-5\.6`),
		regexp.MustCompile(`claude-opus`),
		regexp.MustCompile(`Gemini`),
		regexp.MustCompile(`ornith`),
		regexp.MustCompile(`laguna`),
	}
	documents, err := discoverCutoverProductionDocuments(root)
	if err != nil {
		return err
	}
	for _, relative := range documents {
		path := filepath.Join(root, relative)
		if err := noPatternViolation(path, callerPatterns); err != nil {
			return err
		}
	}
	for _, relative := range cutoverStaticOwnershipDocuments {
		path := filepath.Join(root, relative)
		if err := noPatternViolation(path, staticOwnershipPatterns); err != nil {
			return err
		}
		if relative == "agent-ops/skills/common/plan/SKILL.md" || relative == "agent-ops/skills/common/code-review/SKILL.md" {
			contents, err := os.ReadFile(path)
			if err != nil {
				return err
			}
			if !strings.Contains(string(contents), goPlanValidatorCommand) {
				return fmt.Errorf("cutover ownership violation %s lacks %q", path, goPlanValidatorCommand)
			}
		}
	}
	return nil
}

func discoverCutoverProductionDocuments(root string) ([]string, error) {
	var documents []string
	for _, relativeRoot := range cutoverProductionRoots {
		directory := filepath.Join(root, filepath.FromSlash(relativeRoot))
		err := filepath.WalkDir(directory, func(path string, entry os.DirEntry, walkErr error) error {
			if walkErr != nil {
				return walkErr
			}
			if entry.IsDir() {
				relative, err := filepath.Rel(root, path)
				if err != nil {
					return err
				}
				relative = filepath.ToSlash(relative)
				if entry.Name() == "tests" || strings.HasPrefix(entry.Name(), ".") || relative == "agent-ops/skills/project/orchestrate-agent-task-loop/scripts" {
					return filepath.SkipDir
				}
				return nil
			}
			if !entry.Type().IsRegular() {
				return nil
			}
			relative, err := filepath.Rel(root, path)
			if err != nil {
				return err
			}
			documents = append(documents, filepath.ToSlash(relative))
			return nil
		})
		if err != nil {
			return nil, err
		}
	}
	sort.Strings(documents)
	return documents, nil
}

func noPatternViolation(path string, patterns []*regexp.Regexp) error {
	file, err := os.Open(path)
	if err != nil {
		return err
	}
	defer file.Close()
	scanner := bufio.NewScanner(file)
	line := 0
	for scanner.Scan() {
		line++
		for _, pattern := range patterns {
			if pattern.MatchString(scanner.Text()) {
				return fmt.Errorf("cutover ownership violation %s:%d matches %q", path, line, pattern.String())
			}
		}
	}
	return scanner.Err()
}