package main

import (
	"go/ast"
	"go/parser"
	"go/token"
	"os"
	"path/filepath"
	"strings"
)

type toolbarViolation struct {
	file     string
	line     int
	funcName string
}

// Functions that render full public pages but legitimately skip toolbar injection.
var toolbarExemptFuncs = map[string]bool{
	// Auto-generated SEO listing pages — not block-editable.
	"renderListingPage": true,
	// Historical version preview — has its own preview banner; toolbar edit/publish
	// buttons would be misleading in that context.
	"renderVersionPreview": true,
}

// checkToolbarInjection scans handler Go files for public page render functions
// (identified by containing both getSiteSettings and doc["site_settings"]) and
// verifies each one also injects siteSettings["toolbar"] for the admin toolbar.
func checkToolbarInjection(root string) []toolbarViolation {
	var violations []toolbarViolation

	handlersDir := filepath.Join(root, "internal", "handlers")
	if _, err := os.Stat(handlersDir); err != nil {
		return nil
	}

	_ = filepath.Walk(handlersDir, func(path string, info os.FileInfo, err error) error {
		if err != nil || info.IsDir() || !strings.HasSuffix(path, ".go") {
			return nil
		}
		if strings.HasSuffix(path, "_test.go") {
			return nil
		}

		src, err := os.ReadFile(path)
		if err != nil {
			return nil
		}
		srcText := string(src)

		fset := token.NewFileSet()
		f, err := parser.ParseFile(fset, path, src, 0)
		if err != nil {
			return nil
		}

		relPath, _ := filepath.Rel(root, path)

		for _, decl := range f.Decls {
			fn, ok := decl.(*ast.FuncDecl)
			if !ok || fn.Body == nil {
				continue
			}

			if toolbarExemptFuncs[fn.Name.Name] {
				continue
			}

			bodyStart := fset.Position(fn.Body.Pos()).Offset
			bodyEnd := fset.Position(fn.Body.End()).Offset
			if bodyEnd > len(srcText) {
				bodyEnd = len(srcText)
			}
			body := srcText[bodyStart:bodyEnd]

			hasSiteSettings := strings.Contains(body, "getSiteSettings")
			hasDocAssign := strings.Contains(body, `doc["site_settings"]`)

			if hasSiteSettings && hasDocAssign {
				hasToolbar := strings.Contains(body, `siteSettings["toolbar"]`)
				if !hasToolbar {
					violations = append(violations, toolbarViolation{
						file:     relPath,
						line:     fset.Position(fn.Pos()).Line,
						funcName: fn.Name.Name,
					})
				}
			}
		}

		return nil
	})

	return violations
}