1 files changed, 170 insertions, 0 deletions
diff --git a/cmd/generate/main.go b/cmd/generate/main.go
new file mode 100644
index 0000000..9f1f839
--- /dev/null
+++ b/cmd/generate/main.go
@@ -0,0 +1,170 @@
+package main
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/scanner"
+	"go/token"
+	"net/http"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	if err := run(); err != nil {
+		panic(err)
+	}
+}
+
+func run() error {
+	var fset token.FileSet
+	f, err := parser.ParseFile(&fset, "examples/basic.go", nil, parser.ParseComments|parser.SkipObjectResolution)
+	if err != nil {
+		return err
+	}
+	for _, decl := range f.Decls {
+		f, ok := decl.(*ast.FuncDecl)
+		if !ok {
+			continue
+		}
+		hhRoute := f.Doc.List[len(f.Doc.List)-1].Text
+		var routeSpec string
+		if routeSpec, ok = strings.CutPrefix(hhRoute, "//hh:route "); !ok {
+			continue
+		}
+		rs, err := parseRouteSpec(routeSpec)
+		if err != nil {
+			return err
+		}
+		var wrapper bytes.Buffer
+		wrapper.WriteString("func httpWrapper_")
+		wrapper.WriteString(f.Name.String())
+		wrapper.WriteString("[S any](s S, r *http.Request, w http.ResponseWriter) {")
+        i := 0
+		for _, p := range f.Type.Params.List {
+			for _, n := range p.Names {
+                wrapper.WriteString("\n\tvar")
+                wrapper.WriteString(strconv.Itoa(i))
+                wrapper.WriteString(" := ")
+                wrapper.WriteString(n.Name)
+                i++
+			}
+		}
+        wrapper.WriteString("\t")
+        wrapper.WriteString(f.Name.Name)
+        wrapper.WriteString("(")
+        i = 0
+		for _, p := range f.Type.Params.List {
+			for range p.Names {
+                if i > 0 {
+                    wrapper.WriteString(", ")
+                }
+                wrapper.WriteString("var")
+                wrapper.WriteString(strconv.Itoa(i))
+                i++
+			}
+		}
+        wrapper.WriteString(")\n")
+        wrapper.WriteString("}\n")
+
+		fmt.Printf("`%v`\n`%v`\n`%v`\n", routeSpec, f.Name.Name, rs)
+	}
+	return nil
+}
+
+type routeSpec struct {
+	method     string
+	path       string
+	parameters []routeSpecParam
+}
+
+type routeSpecParam struct {
+	name      string
+	extractor string
+}
+
+func parseRouteSpec(s string) (routeSpec, error) {
+	s = strings.TrimRight(s, " \n")
+	var rs routeSpec
+	for _, method := range []string{
+		http.MethodGet,
+		http.MethodHead,
+		http.MethodPost,
+		http.MethodPut,
+		http.MethodPatch,
+		http.MethodDelete,
+		http.MethodConnect,
+		http.MethodOptions,
+		http.MethodTrace,
+	} {
+		if rest, ok := strings.CutPrefix(s, method+" "); ok {
+			s = rest
+			rs.method = method
+			break
+		}
+	}
+
+	for {
+		if commaPos := strings.IndexByte(s, ','); commaPos != -1 {
+			rs.path = s[:commaPos]
+			s = s[commaPos+1:]
+		} else {
+			rs.path = s
+			return rs, nil
+		}
+
+		s = strings.TrimLeft(s, " ")
+		if s == "" {
+			break
+		}
+
+		end := -1
+		for i := 0; i < len(s); i++ {
+			if 'a' <= s[i] && s[i] <= 'z' ||
+				'A' <= s[i] && s[i] <= 'Z' ||
+				s[i] == '_' {
+				continue
+			}
+			if s[i] == ':' {
+				end = i
+				break
+			}
+			return rs, errors.New("Expected ':' to mark end of parameter name, got " + s[i:i+1])
+		}
+		if end == -1 {
+			return rs, errors.New("Expected ':' to mark end of parameter name, got end of line")
+		}
+		var p routeSpecParam
+		p.name = s[:end]
+		s = s[end+1:]
+
+		s = strings.TrimLeft(s, " ")
+
+		expr, err := parser.ParseExpr(s)
+		if el, ok := err.(scanner.ErrorList); err == nil || ok && el[0].Msg == "expected 'EOF', found ','" {
+			switch expr := expr.(type) {
+			case *ast.Ident:
+				switch expr.Name {
+				case "query":
+					p.extractor = ":" + expr.Name
+				default:
+					return rs, errors.New("Unexpected extractor " + expr.Name)
+				}
+			case *ast.CallExpr:
+				p.extractor = s[expr.Pos()-1 : expr.End()-1]
+			default:
+				return rs, errors.New("Unexpected extractor" + s[expr.Pos()-1:expr.End()-1])
+			}
+		} else {
+			return rs, err
+		}
+		s = s[expr.End()-1:]
+
+		rs.parameters = append(rs.parameters, p)
+	}
+
+	return rs, nil
+}