Copy and adapt role helper generator to new system

cmd/NewRoleHelperGenerator/main.go

@@ -0,0 +1,195 @@
+/*
+Tool for generating helper functions for storage.Role structs inside of the storage package
+It generates the following functions:
+  - CollapseRolesIntoOne: Collapse a list of roles into one singular role. Each value will be set to the
+    value of the role with the highest priority
+  - RoleDeepCopy: Copy a role, including all arrays. Every value will be copied too
+  - CompareRoles: Compare two roles. Returns true only if all fields are equal
+    (if one of the fields is nil, that field is seen as equal)
+*/
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"regexp"
+	"strings"
+
+	"git.mstar.dev/mstar/goutils/sliceutils"
+)
+
+var findRoleStructRegex = regexp.MustCompile(`type Role struct \{([\s\S]+)\}\n\n/\*`)
+
+var (
+	flagInputFile  = flag.String("input", "", "Specify the input file. If empty, read from stdin")
+	flagOutputFile = flag.String(
+		"output",
+		"",
+		"Specify the output file. If empty, writes to stdout",
+	)
+	flagOutputModule = flag.String(
+		"mod",
+		"",
+		"Module for the output file. If empty, use mod of input file",
+	)
+)
+
+func main() {
+	flag.Parse()
+	var input io.Reader
+	var output io.Writer
+
+	if *flagInputFile == "" {
+		input = os.Stdin
+	} else {
+		file, err := os.Open(*flagInputFile)
+		if err != nil {
+			panic(err)
+		}
+		defer file.Close()
+		input = file
+	}
+	if *flagOutputFile == "" {
+		output = os.Stdout
+	} else {
+		file, err := os.Create(*flagOutputFile)
+		if err != nil {
+			panic(err)
+		}
+		defer file.Close()
+		output = file
+	}
+
+	data, err := io.ReadAll(input)
+	if err != nil {
+		panic(err)
+	}
+	if !findRoleStructRegex.Match(data) {
+		panic("Input doesn't contain role struct")
+	}
+	content := findRoleStructRegex.FindStringSubmatch(string(data))[1]
+	lines := strings.Split(content, "\n")
+	lines = sliceutils.Map(lines, func(t string) string { return strings.TrimSpace(t) })
+	importantLines := sliceutils.Filter(lines, func(t string) bool {
+		if strings.HasPrefix(t, "//") {
+			return false
+		}
+		if strings.Contains(t, "gorm.Model") {
+			return false
+		}
+		data := sliceutils.Filter(strings.Split(t, " "), func(t string) bool { return t != "" })
+		if len(data) < 2 {
+			return false
+		}
+		if !strings.HasPrefix(data[1], "*") && !strings.HasPrefix(data[1], "[]") {
+			return false
+		}
+		return true
+	})
+	nameTypeMap := map[string]string{}
+	for _, line := range importantLines {
+		parts := sliceutils.Filter(strings.Split(line, " "), func(t string) bool { return t != "" })
+		nameTypeMap[parts[0]] = parts[1]
+	}
+	pkgString, _, _ := strings.Cut(string(data), "\n")
+
+	outBuilder := strings.Builder{}
+	outBuilder.WriteString(`// Code generated by cmd/RolesGenerator DO NOT EDIT.
+// If you need to refresh the content, run go generate again
+`)
+	if *flagOutputModule == "" {
+		outBuilder.WriteString(pkgString + "\n\n")
+	} else {
+		outBuilder.WriteString("package " + *flagOutputModule + "\n\n")
+	}
+	outBuilder.WriteString(
+		`import (
+  "slices"
+  "git.mstar.dev/mstar/goutils/sliceutils"
+    "git.mstar.dev/mstar/linstrom/storage-new/models"
+)
+
+`,
+	)
+
+	// Build role collapse function
+	outBuilder.WriteString(
+		`func CollapseRolesIntoOne(roles ...models.Role) models.Role {
+  startingRole := RoleDeepCopy(models.DefaultUserRole)
+  slices.SortFunc(roles, func(a, b models.Role) int { return int(int64(a.Priority)-int64(b.Priority)) })
+  for _, role := range roles {
+`)
+	// Write all the stupid conditions here
+	for valName, valType := range nameTypeMap {
+		if strings.HasPrefix(valType, "[]") {
+			outBuilder.WriteString(fmt.Sprintf(`    if role.%s != nil {
+      startingRole.%s = append(startingRole.%s, role.%s...)
+    }
+`, valName, valName, valName, valName))
+		} else {
+			outBuilder.WriteString(fmt.Sprintf(`    if role.%s != nil {
+      *startingRole.%s = *role.%s
+    }
+`, valName, valName, valName))
+		}
+	}
+	// Then finish up with the end of the function
+	outBuilder.WriteString(
+		`  }
+  return startingRole
+}
+`)
+
+	// Then build the deep copy function
+	outBuilder.WriteString("\nfunc RoleDeepCopy(o models.Role) models.Role {\n")
+	outBuilder.WriteString(`  n := models.Role{}
+  n.Model = o.Model
+  n.Name = o.Name
+  n.Priority = o.Priority
+  n.IsUserRole = o.IsUserRole
+  n.IsBuiltIn = o.IsBuiltIn
+`)
+	for valName, valType := range nameTypeMap {
+		if strings.HasPrefix(valType, "[]") {
+			outBuilder.WriteString(fmt.Sprintf("  n.%s = slices.Clone(o.%s)\n", valName, valName))
+		} else {
+			outBuilder.WriteString(fmt.Sprintf(`  if o.%s == nil { n.%s = nil } else {
+      t := *o.%s
+      n.%s = &t
+    }
+`, valName, valName, valName, valName))
+		}
+	}
+	outBuilder.WriteString("  return n\n}\n\n")
+
+	// Build compare function
+	outBuilder.WriteString("func CompareRoles(a, b *models.Role) bool {\n")
+	outBuilder.WriteString("  return ")
+	lastName, lastType := "", ""
+	for valName, valType := range nameTypeMap {
+		lastName = valName
+		lastType = valType
+		outBuilder.WriteString(fmt.Sprintf("(a.%s == nil || b.%s == nil || ", valName, valName))
+		if strings.HasPrefix(valType, "[]") {
+			outBuilder.WriteString(
+				fmt.Sprintf("sliceutils.CompareUnordered(a.%s,b.%s)) && ", valName, valName),
+			)
+		} else {
+			outBuilder.WriteString(fmt.Sprintf("a.%s == b.%s) && ", valName, valName))
+		}
+	}
+	outBuilder.WriteString("(a == nil || b == nil || ")
+	if strings.HasPrefix(lastType, "[]") {
+		outBuilder.WriteString(
+			fmt.Sprintf("sliceutils.CompareUnordered(a.%s,b.%s))", lastName, lastName),
+		)
+	} else {
+		outBuilder.WriteString(fmt.Sprintf("a.%s == b.%s)", lastName, lastName))
+	}
+	outBuilder.WriteString("\n}")
+
+	// And write the entire thing to the output
+	fmt.Fprint(output, outBuilder.String())
+}