Implement a state manager POC

rowbot

@@ -97,23 +97,6 @@ b64_encode() {
 
 # code reloading helpers
 
-get_option() {
-  local var_name=${1//-/_}
-  local env_var=${var_name^^}
-
-  if [[ ! -v config[$1] || -v OPT_OW ]]; then
-    if [[ -v $env_var ]]; then
-      config[$1]=${!env_var}
-    elif [[ -v opts[$1] ]]; then
-      config[$1]=${opts[$1]}
-    elif [[ -v $var_name ]]; then
-      config[$1]=${!var_name}
-    elif (( $# > 1 )); then
-      config[$1]=$2
-    fi
-  fi
-}
-
 is_reloaded() {
   [[ $RELOADED = yes ]] || (( RELOAD_COUNT ))
 }
@@ -157,11 +140,7 @@ shuffle() {
   done
 }
 
-# misc
-
-is_running () {
-  kill -0 "$1" 2>/dev/null
-}
+# process management and friends
 
 die() {
   local fmt=$1
@@ -181,6 +160,12 @@ has() {
   fi
 }
 
+is_running () {
+  kill -0 "$1" 2>/dev/null
+}
+
+# misc
+
 run_callbacks() {
   if (( ! $# )); then
     return 1
@@ -245,12 +230,12 @@ url() {
 }
 
 ###
-# configure rowbot's environment
+# Prepare rowbot's configuration
 ###
 
 # parse command line arguments
 
-declare -A opts
+declare -A config opts
 cmd_line=( "${@:0}" )
 
 while (( $# )); do
@@ -280,6 +265,8 @@ done
 
 # load custom configuration files
 
+mapfile -t old_set < <(compgen -v)
+
 for file do
   if [[ -f $file ]]; then
     # These files (if any) are provided dynamically at run-time.
@@ -290,27 +277,131 @@ for file do
   fi
 done
 
+mapfile -t new_set < <(compgen -v)
+
+for new in "${new_set[@]}"; do
+  found=0
+
+  for old in "${old_set[@]}"; do
+    if [[ $new = "$old" ]]; then
+      found=1
+      break
+    fi
+  done
+
+  if (( !found )); then
+    config[$new]=${!new}
+  fi
+done
+
+for setting in "${!opts[@]}"; do
+  config[$setting]=${opts[$setting]}
+done
+
+while IFS= read -r setting; do
+  config[${setting,,}]=${!setting}
+done < <(compgen -e)
+
 # cleanup
 
-unset key file
+unset key opts old_set file new_set new found old setting
 
 ###
-# load default config
+# state management
 ###
 
-declare -A config
+state_resolve() {
+  local ns=${NS-global} managed found=0
+  declare -gA __rowbot_state_store_"$ns"
+  declare -n ns_config=__rowbot_state_store_"$ns"
 
-get_option owner "${USER:-uplime}"
-get_option trigger \`
-get_option dev yes
+  if [[ $ns != global ]]; then
+    for managed in "${states_managed[@]}"; do
+      if [[ $managed = "$ns" ]]; then
+        found=1
+        break
+      fi
+    done
+
+    if (( !found )); then
+      states_managed+=( "$ns" )
+    fi
+  fi
+
+  if [[ -v config[$1] ]]; then
+    ns_config[$1]=${config[$1]}
+  elif [[ -v DEFAULT ]]; then
+    ns_config[$1]=$DEFAULT
+  else
+    return 1
+  fi
+}
+
+state_get() {
+  local ns=${NS-global}
+  # The `ns_config` variable is a reference to an array
+  # shellcheck disable=SC2178
+  declare -n ns_config=__rowbot_state_store_"$ns"
+
+  if [[ -v ns_config[$1] ]]; then
+    printf %s "${ns_config[$1]}"
+  elif [[ -v DEFAULT ]]; then
+    printf %s "$DEFAULT"
+  else
+    return 1
+  fi
+}
+
+state_has() {
+  local ns=${NS-global} found=1 managed
+  declare -n ns_config=__rowbot_state_store_"$ns"
+
+  for managed in "${ns_config[@]}"; do
+    if [[ $managed = "$1" ]]; then
+      found=0
+      break
+    fi
+  done
+
+  return "$found"
+}
+
+on_sys_init_001_state() {
+  states_managed=( global )
+}
+
+on_sys_before_999_state() {
+  local managed
+
+  for managed in "${states_managed[@]}"; do
+    put_assoc_array __rowbot_state_store_"$managed"
+  done
+
+  put_array states_managed
+}
+
+on_sys_after_001_state() {
+  local managed
+  get_array states_managed
+
+  for managed in "${states_managed[@]}"; do
+    get_assoc_array __rowbot_state_store_"$managed"
+  done
+}
 
 ###
 # logger
 ###
 
 log() {
-  if [[ -v LOG_LEVEL ]] && (( log_levels[$log_level] <= log_levels[$LOG_LEVEL] )); then
-    printf "%s: $1\n" "${LOG_LEVEL^^}" "${@:2}" >&"$log_fd"
+  if NS=log state_has fd; then
+    # The only possible fail conditions are already checked for.
+    # shellcheck disable=SC2155
+    local level=$(NS=log state_get level) fd=$(NS=log state_get fd)
+
+    if (( log_levels[$level] <= log_levels[$LOG_LEVEL] )); then
+      printf "%s: $1\n" "${LOG_LEVEL^^}" "${@:2}" >&"$fd"
+    fi
   fi
 }
 
@@ -346,40 +437,50 @@ log_has_level() {
   return 1
 }
 
-on_sys_init_001_log() {
+on_sys_init_005_log() {
   declare -gA log_levels=( [trace]=1 [debug]=2 [info]=3 [warn]=4 [error]=5 )
-  get_option log-level info
+  NS=log DEFAULT=info state_resolve level
 
-  if ! log_has_level "${config[log-level]}"; then
-    die "%s is not a valid logging level" "${config[log-level]}"
+  if ! log_has_level "$(NS=log state_get level)"; then
+    die "%s is not a valid logging level" "$(NS=log state_get level)"
   fi
 
-  get_option log ""
-  get_option overwrite no
-  log_level=${config[log-level]}
+  local log_fd=1
 
-  if [[ ${config[log]} ]]; then
+  if [[ -v ${config[log]} ]]; then
     if [[ ${config[overwrite]} = yes ]]; then
       exec {log_fd}>"${config[log]}"
     else
       exec {log_fd}>>"${config[log]}"
     fi
-  else
-    log_fd=1
   fi
+
+  NS=log DEFAULT=$log_fd state_resolve fd
 }
 
 on_sys_before_999_log() {
-  if [[ -v log_fd ]] && (( log_fd != 1 )); then
-    log_debug "shutting logger down for reload"
-    exec {log_fd}>&-
+  if NS=log state_has fd; then
+    # The only possible fail condition is already checked for.
+    # shellcheck disable=2155
+    local fd=$(NS=log state_get fd)
+
+    if (( fd != 1 )); then
+      log_debug "shutting logger down for reload"
+      exec {fd}>&-
+    fi
   fi
 }
 
 on_sys_exit_999_log() {
-  if [[ -v log_fd ]] && (( log_fd != 1 )); then
-    log_debug "shutting logger down for good"
-    exec {log_fd}>&-
+  if NS=log state_has fd; then
+    # The only possible fail condition is already checked for.
+    # shellcheck disable=2155
+    local fd=$(NS=log state_get fd)
+
+    if (( fd != 1 )); then
+      log_debug "shutting logger down for good"
+      exec {fd}>&-
+    fi
   fi
 }