package validation

import (
	"context"
	"errors"
	"path/filepath"
	"strings"
	"testing"
)

func TestRunFileChecksUseSelectedInputsAndFullReferenceLookup(t *testing.T) {
	repository := newTreeRepository(t)
	writeTreeFile(t, repository, "go.mod", []byte("module example.com/root\n\ngo 1.25.0\nreplace example.com/rootdep => ./missing\n"))
	writeTreeFile(t, repository, "go.work", []byte("go 1.25.0\n"))
	writeTreeFile(t, repository, "outside.go", []byte("package outside\nfunc broken( ){}\n"))
	writeTreeFile(t, repository, "outside.bin", []byte(strings.Repeat("x", 160)))
	writeTreeFile(t, repository, "nested/go.mod", []byte("module example.com/nested\n\ngo 1.25.0\n"))
	writeTreeFile(t, repository, "nested/source.go", []byte("package nested\n\nfunc ready() {}\n"))
	writeTreeFile(t, repository, "nested/ignored.bin", []byte(strings.Repeat("x", 160)))
	writeTreeFile(t, repository, "nested/docs/guide.md", []byte("# Guide\n\n[details](../../sibling/docs/target.md#details)\n"))
	writeTreeFile(t, repository, "nested/child/go.mod", []byte("module example.com/nested/child\n"))
	writeTreeFile(t, repository, "nested/child/broken.go", []byte("package child\nfunc broken( ){}\n"))
	writeTreeFile(t, repository, "nested/child/go.work", []byte("go 1.25.0\n"))
	writeTreeFile(t, repository, "sibling/go.mod", []byte("module example.com/sibling\n\nreplace example.com/siblingdep => ./missing\n"))
	writeTreeFile(t, repository, "sibling/go.work", []byte("go 1.25.0\n"))
	writeTreeFile(t, repository, "sibling/broken.go", []byte("package sibling\nfunc broken( ){}\n"))
	writeTreeFile(t, repository, "sibling/outside.bin", []byte(strings.Repeat("x", 160)))
	writeTreeFile(t, repository, "sibling/docs/target.md", []byte("# Details\n\n[broken](missing.md)\n"))
	writeTreeFile(t, repository, "shared/broken.go", []byte("package shared\nfunc broken( ){}\n"))
	commit := commitCandidateTree(t, repository)
	installGoShim(t, "", false)
	moduleDir := filepath.Join(repository, "nested")
	settings := Settings{
		GoFormat: true,
		ModuleDistribution: ModuleDistributionSettings{
			WorkspaceFiles:    true,
			LocalReplacements: true,
		},
		FileSize: &FileSizeSettings{LimitBytes: int64Pointer(100), Exclusions: []string{"ignored.bin"}},
		Markdown: &MarkdownSettings{EnforceCheckoutBoundary: true},
	}
	request := Request{RepositoryDir: repository, ModuleDir: moduleDir, Commit: commit, Settings: settings}
	if err := Run(context.Background(), request); err != nil {
		t.Fatalf("selected module checks = %v, want out-of-scope violations ignored and cross-module anchor resolved", err)
	}

	request.Settings.FileSize.Exclusions = nil
	err := Run(context.Background(), request)
	assertScopedFailure(t, err, FileSize, "nested/ignored.bin")

	writeTreeFile(t, repository, "nested/broken.go", []byte("package nested\nfunc broken( ){}\n"))
	request.Commit = commitCandidateTree(t, repository)
	request.Settings = Settings{GoFormat: true}
	assertScopedFailure(t, Run(context.Background(), request), GoFormat, "nested/broken.go")

	writeTreeFile(t, repository, "nested/go.work", []byte("go 1.25.0\n"))
	request.Commit = commitCandidateTree(t, repository)
	request.Settings = Settings{ModuleDistribution: ModuleDistributionSettings{WorkspaceFiles: true}}
	assertScopedFailure(t, Run(context.Background(), request), WorkspaceFiles, "nested/go.work")

	writeTreeFile(t, repository, "nested/go.mod", []byte("module example.com/nested\n\ngo 1.25.0\nreplace example.com/nesteddep => ./missing\n"))
	request.Commit = commitCandidateTree(t, repository)
	request.Settings = Settings{ModuleDistribution: ModuleDistributionSettings{LocalReplacements: true}}
	assertScopedFailure(t, Run(context.Background(), request), LocalReplacements, "nested/go.mod")

	writeTreeFile(t, repository, "nested/docs/guide.md", []byte("# Guide\n\n[details](../../sibling/docs/target.md#details)\n\n[missing](absent.md)\n"))
	request.Commit = commitCandidateTree(t, repository)
	request.Settings = Settings{Markdown: &MarkdownSettings{}}
	assertScopedFailure(t, Run(context.Background(), request), MarkdownLinks, "nested/docs/guide.md")

	request.Settings = Settings{GoFormat: true, SharedFiles: []string{"shared/broken.go"}}
	assertScopedFailure(t, Run(context.Background(), request), GoFormat, "shared/broken.go")
}

func assertScopedFailure(t *testing.T, err error, check Check, path string) {
	t.Helper()
	failure, ok := err.(*Failure)
	if !ok || failure.Check != check {
		t.Fatalf("validation error = %v, want %s failure", err, check)
	}
	for _, finding := range failure.Findings {
		if finding.Path == path {
			return
		}
	}
	t.Fatalf("%s findings = %#v, want path %q", check, failure.Findings, path)
}

func TestFileSizeExclusionsAreModuleRelative(t *testing.T) {
	repository := newTreeRepository(t)
	writeTreeFile(t, repository, "nested/go.mod", []byte("module example.com/nested\n"))
	writeTreeFile(t, repository, "nested/dist/output.bin", []byte(strings.Repeat("x", 20)))
	writeTreeFile(t, repository, "nested/dist-old/output.bin", []byte(strings.Repeat("x", 20)))
	commit := commitCandidateTree(t, repository)
	tree, err := ReadCandidateTreeForScope(context.Background(), repository, commit, TreeScope{ModuleDir: filepath.Join(repository, "nested")})
	if err != nil {
		t.Fatal(err)
	}
	cleanupCandidateTree(t, tree)
	settings := fileSizeSettingsForModule(&FileSizeSettings{LimitBytes: int64Pointer(10), Exclusions: []string{"./dist/"}}, tree.modulePath)
	err = checkFileSize(tree, settings)
	var failure *Failure
	if !errors.As(err, &failure) || failure.Check != FileSize || len(failure.Findings) != 1 || failure.Findings[0].Path != "nested/dist-old/output.bin" {
		t.Fatalf("module-relative file-size exclusion error = %v, want only nested/dist-old/output.bin", err)
	}
}

func TestSharedFileSelectionFailureCarriesCauseAndPresentation(t *testing.T) {
	repository := newTreeRepository(t)
	writeTreeFile(t, repository, "go.mod", []byte("module example.com/root\n"))
	commit := commitCandidateTree(t, repository)
	installGoShim(t, "", false)
	err := Run(context.Background(), Request{
		RepositoryDir: repository,
		Commit:        commit,
		Settings:      Settings{SharedFiles: []string{"missing.txt"}},
	})
	var failure *Failure
	if !errors.As(err, &failure) || failure.Check != SharedFiles || failure.Cause == nil || len(failure.Findings) != 1 || failure.Findings[0].Path != "missing.txt" {
		t.Fatalf("shared-file selection error = %#v, want path, cause, and shared-files identity", err)
	}
	if !strings.Contains(err.Error(), "shared-files") || !strings.Contains(err.Error(), "missing.txt") {
		t.Fatalf("shared-file error text = %q, want existing check/path presentation", err)
	}
}