1 files changed, 113 insertions, 0 deletions
diff --git a/pkg/config/menu.go b/pkg/config/menu.go
new file mode 100644
index 0000000..7321c7b
--- /dev/null
+++ b/pkg/config/menu.go
@@ -0,0 +1,113 @@
+package config
+
+import (
+	"regexp"
+	"strings"
+
+	"github.com/pkg/errors"
+)
+
+var reValidMenuName = regexp.MustCompile(`^[\w\._]+$`)
+var reValidKey = regexp.MustCompile(`^\w$`)
+
+// Menu struct describes a screen menu
+type Menu struct {
+	// Banner is the banner to display before the menu
+	Banner string `yaml:"Banner"`
+	// Commands is the list of commands in the menu
+	MenuEntries []MenuEntry `yaml:"MenuEntries"`
+}
+
+// MenuEntry struct describes a menu entry
+type MenuEntry struct {
+	// Key is the key associated with the action. We need to store it as a string because of how yaml unmarshal works
+	Key string `yaml:"Key"`
+	// Label is the text displayed on the menu
+	Label string `yaml:"Label"`
+	// Action is the action executed when the menu entry is selected
+	Action string `yaml:"Action"`
+}
+
+func (m *Menu) validate(name string) error {
+	// validate name
+	if ok := reValidMenuName.MatchString(name); !ok {
+		return errors.New("Invalid menu name, must be an alphanumeric word and match regex `^[\\w\\._]+$` : " + name)
+	}
+	// Banner is just any string, nothing to validate
+	// MenuEntries
+	if len(m.MenuEntries) == 0 {
+		return errors.New("A Menu needs MenuEntries to be valid")
+	}
+	// Duplicate detection is natively handled by the yaml parser
+	for i := 0; i < len(m.MenuEntries); i++ {
+		m.MenuEntries[i].validate()
+		if m.MenuEntries[i].Action == "menu "+name {
+			return errors.New("A menu shall not loop on itself")
+		}
+	}
+	// Loop test
+	return nil
+}
+
+func (m *Menu) validateConsistency(c *Config) error {
+	// Necessary menus
+	if _, ok := c.Menus["anonymous"]; !ok {
+		return errors.New("No anonymous menu declared")
+	}
+	if _, ok := c.Menus["logged_in"]; !ok {
+		return errors.New("No logged_in menu declared")
+	}
+	// Validate actions
+	menus := map[string]bool{
+		"anonymous": true,
+		"logged_in": true,
+	}
+	playable := make(map[string]bool)
+	for k, v := range c.Menus {
+		for _, e := range v.MenuEntries {
+			tokens := strings.Split(e.Action, " ")
+			switch tokens[0] {
+			case "menu":
+				if _, ok := c.Menus[tokens[1]]; ok {
+					menus[tokens[1]] = true
+				} else {
+					return errors.New("menu action " + tokens[1] + " in menu " + k + " does not exist")
+				}
+			case "play":
+				if _, ok := c.Games[tokens[1]]; ok {
+					playable[tokens[1]] = true
+				} else {
+					return errors.New("play action " + tokens[1] + " in menu " + k + " does not exist")
+				}
+			}
+		}
+	}
+	// Check for unreachables
+	for k, _ := range c.Menus {
+		if _, ok := menus[k]; !ok {
+			return errors.New("unreachable menu : " + k)
+		}
+	}
+	for k, _ := range c.Games {
+		if _, ok := playable[k]; !ok {
+			return errors.New("unplayable game : " + k)
+		}
+	}
+	return nil
+}
+
+func (m *MenuEntry) validate() error {
+	// Key
+	if ok := reValidKey.MatchString(m.Key); !ok {
+		return errors.New("Invalid Key, must be exactly one alphanumeric character and match regex `^\\w$` : " + m.Key)
+	}
+	// Label
+	if len(m.Label) <= 0 {
+		return errors.New("Invalid Label, cannot be empty")
+	}
+	// Action
+	if err := validateAction(m.Action); err != nil {
+		return errors.Wrap(err, "Invalid Action in MenuEntry")
+	}
+	return nil
+}