Dependancy between flags

libfic/db.go

@@ -172,6 +172,16 @@ CREATE TABLE IF NOT EXISTS exercice_flags(
   cksum BINARY(64) NOT NULL,
   FOREIGN KEY(id_exercice) REFERENCES exercices(id_exercice)
 ) DEFAULT CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_ci;
+`); err != nil {
+		return err
+	}
+	if _, err := db.Exec(`
+CREATE TABLE IF NOT EXISTS exercice_flags_deps(
+  id_flag INTEGER NOT NULL,
+  id_flag_dep INTEGER NOT NULL,
+  FOREIGN KEY(id_flag) REFERENCES exercice_flags(id_flag),
+  FOREIGN KEY(id_flag_dep) REFERENCES exercice_flags(id_flag)
+) DEFAULT CHARACTER SET = utf8 COLLATE = utf8_bin;
 `); err != nil {
 		return err
 	}

libfic/flag.go

@@ -124,6 +124,8 @@ func (k Flag) Update() (int64, error) {
 func (k Flag) Delete() (int64, error) {
 	if _, err := DBExec("DELETE FROM exercice_files_deps WHERE id_flag = ?", k.Id); err != nil {
 		return 0, err
+	} else if _, err := DBExec("DELETE FROM exercice_flags_deps WHERE id_flag = ?", k.Id); err != nil {
+		return 0, err
 	} else if _, err := DBExec("DELETE FROM flag_choices WHERE id_flag = ?", k.Id); err != nil {
 		return 0, err
 	} else if res, err := DBExec("DELETE FROM exercice_flags WHERE id_flag = ?", k.Id); err != nil {
@@ -139,6 +141,8 @@ func (k Flag) Delete() (int64, error) {
 func (e Exercice) WipeFlags() (int64, error) {
 	if _, err := DBExec("DELETE FROM exercice_files_deps WHERE id_flag IN (SELECT id_flag FROM exercice_flags WHERE id_exercice = ?)", e.Id); err != nil {
 		return 0, err
+	} else if _, err := DBExec("DELETE FROM exercice_flags_deps WHERE id_flag IN (SELECT id_flag FROM exercice_flags WHERE id_exercice = ?)", e.Id); err != nil {
+		return 0, err
 	} else if _, err := DBExec("DELETE FROM flag_choices WHERE id_flag IN (SELECT id_flag FROM exercice_flags WHERE id_exercice = ?)", e.Id); err != nil {
 		return 0, err
 	} else if res, err := DBExec("DELETE FROM exercice_flags WHERE id_exercice = ?", e.Id); err != nil {
@@ -150,6 +154,35 @@ func (e Exercice) WipeFlags() (int64, error) {
 	}
 }
 
+// AddDepend insert a new dependency to a given flag.
+func (k Flag) AddDepend(d Flag) (err error) {
+	_, err = DBExec("INSERT INTO exercice_flags_deps (id_flag, id_flag_dep) VALUES (?, ?)", k.Id, d.Id)
+	return
+}
+
+// GetDepends retrieve the flag's dependency list.
+func (k Flag) GetDepends() ([]Flag, error) {
+	if rows, err := DBQuery("SELECT id_flag_dep FROM exercice_flags_deps WHERE id_flag = ?", k.Id); err != nil {
+		return nil, err
+	} else {
+		defer rows.Close()
+
+		var deps = make([]Flag, 0)
+		for rows.Next() {
+			var d int64
+			if err := rows.Scan(&d); err != nil {
+				return nil, err
+			}
+			deps = append(deps, Flag{d, k.IdExercice, "", "", false, nil, []byte{}})
+		}
+		if err := rows.Err(); err != nil {
+			return nil, err
+		}
+
+		return deps, nil
+	}
+}
+
 // Check if the given val is the expected one for this flag.
 func (k Flag) Check(val []byte) bool {
 	if k.IgnoreCase {

libfic/reset.go

@@ -34,7 +34,7 @@ func ResetGame() (error) {
 
 // ResetExercices wipes out all challenges (both attempts and statements).
 func ResetExercices() (error) {
-	return truncateTable("team_hints", "exercice_files_deps", "exercice_files", "flag_found", "flag_choices", "exercice_flags", "exercice_solved", "exercice_tries", "exercice_hints", "mcq_found", "mcq_entries", "exercice_mcq", "exercice_tags", "exercices", "themes")
+	return truncateTable("team_hints", "exercice_files_deps", "exercice_files", "flag_found", "exercice_flags_deps", "flag_choices", "exercice_flags", "exercice_solved", "exercice_tries", "exercice_hints", "mcq_found", "mcq_entries", "exercice_mcq", "exercice_tags", "exercices", "themes")
 }
 
 // ResetTeams wipes out all teams, incluings members and attempts.

libfic/team.go

@@ -124,6 +124,25 @@ func (t Team) CanDownload(f EFile) bool {
 	}
 }
 
+// CanSeeFlag checks if the Team has access to the given flag.
+func (t Team) CanSeeFlag(k Flag) bool {
+	if deps, err := k.GetDepends(); err != nil {
+		log.Printf("Unable to retrieve flag dependencies: %s\n", err)
+		return false
+	} else {
+		res := true
+
+		for _, dep := range deps {
+			if t.HasPartiallySolved(dep) == nil {
+				res = false
+				break
+			}
+		}
+
+		return res
+	}
+}
+
 // NbTry retrieves the number of attempts made by the Team to the given challenge.
 func NbTry(t *Team, e Exercice) int {
 	var cnt *int

libfic/team_my.go

@@ -175,6 +175,11 @@ func MyJSONTeam(t *Team, started bool) (interface{}, error) {
 					for _, k := range flags {
 						var flag myTeamFlag
 
+						if t != nil && !t.CanSeeFlag(k) {
+							// Dependancy missing, skip the flag for now
+							continue
+						}
+
 						if fl, err := k.GetMCQJustification(); err == nil {
 							fl.Checksum = k.Checksum
 							if t != nil && t.HasPartiallySolved(k) != nil {