replace string settings with typed enums

- preserve local wall-time handling and import completion timestamps
- validate invalid properties without overwriting items

src/model.rs

@@ -1,3 +1,5 @@
+use std::{fmt, str::FromStr};
+
 #[derive(Debug, Clone, PartialEq)]
 pub struct Item {
     pub id: i64,
@@ -30,7 +32,7 @@ pub struct Category {
     pub id: i64,
     pub name: String,
     pub parent_id: Option<i64>,
-    pub kind: String,
+    pub kind: CategoryKind,
     pub match_text: String,
     pub exclusive: bool,
 }
@@ -39,9 +41,9 @@ pub struct Category {
 pub struct ViewDef {
     pub id: i64,
     pub name: String,
-    pub kind: String,
+    pub kind: ViewKind,
     pub filter_value: String,
-    pub sort_key: String,
+    pub sort_key: SortKey,
     pub show_done: bool,
     pub filter_expr: String,
     pub columns: Vec<ViewColumn>,
@@ -53,7 +55,7 @@ pub struct ViewColumn {
     pub field: String,
     pub heading: String,
     pub width: u16,
-    pub aggregate: String,
+    pub aggregate: Aggregate,
 }
 
 #[derive(Debug, Clone, PartialEq)]
@@ -93,7 +95,7 @@ pub struct CategoryRule {
     pub id: i64,
     pub category_id: i64,
     pub condition_expr: String,
-    pub action_kind: String,
+    pub action_kind: RuleActionKind,
     pub action_value: String,
     pub enabled: bool,
 }
@@ -121,11 +123,11 @@ pub struct ItemChanges {
 pub struct DocumentSettings {
     pub description: String,
     pub backup_on_open: bool,
-    pub trash_policy: String,
-    pub done_policy: String,
+    pub trash_policy: TrashPolicy,
+    pub done_policy: DonePolicy,
     pub automatic_filing: bool,
-    pub date_order: String,
-    pub week_start: String,
+    pub date_order: DateOrder,
+    pub week_start: WeekStart,
     pub default_time: String,
     pub morning_time: String,
     pub afternoon_time: String,
@@ -138,11 +140,11 @@ impl Default for DocumentSettings {
         Self {
             description: String::new(),
             backup_on_open: false,
-            trash_policy: "on-demand".into(),
-            done_policy: "keep".into(),
+            trash_policy: TrashPolicy::OnDemand,
+            done_policy: DonePolicy::Keep,
             automatic_filing: true,
-            date_order: "ymd".into(),
-            week_start: "monday".into(),
+            date_order: DateOrder::YearMonthDay,
+            week_start: WeekStart::Monday,
             default_time: "09:00".into(),
             morning_time: "09:00".into(),
             afternoon_time: "13:00".into(),
@@ -151,3 +153,102 @@ impl Default for DocumentSettings {
         }
     }
 }
+macro_rules! string_enum {
+    ($name:ident { $($variant:ident => $value:literal),+ $(,)? }) => {
+        #[derive(Debug, Clone, Copy, PartialEq, Eq)]
+        pub enum $name {
+            $($variant),+
+        }
+
+        impl $name {
+            pub const fn as_str(self) -> &'static str {
+                match self {
+                    $(Self::$variant => $value),+
+                }
+            }
+        }
+
+        impl fmt::Display for $name {
+            fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+                formatter.write_str(self.as_str())
+            }
+        }
+
+        impl FromStr for $name {
+            type Err = String;
+
+            fn from_str(value: &str) -> Result<Self, Self::Err> {
+                match value {
+                    $($value => Ok(Self::$variant),)+
+                    _ => Err(format!("unsupported {} {value:?}", stringify!($name))),
+                }
+            }
+        }
+    };
+}
+
+string_enum!(CategoryKind {
+    Standard => "standard",
+    Date => "date",
+    Numeric => "numeric",
+});
+
+string_enum!(ViewKind {
+    List => "list",
+    Category => "category",
+    Upcoming => "upcoming",
+    Done => "done",
+    Datebook => "datebook",
+    Trash => "trash",
+});
+
+string_enum!(SortKey {
+    Manual => "manual",
+    When => "when",
+    Done => "done",
+    Priority => "priority",
+    Updated => "updated",
+});
+
+string_enum!(Aggregate {
+    None => "none",
+    Sum => "sum",
+    Average => "avg",
+    Count => "count",
+    Minimum => "min",
+    Maximum => "max",
+});
+
+string_enum!(RuleActionKind {
+    Assign => "assign",
+    Exclude => "exclude",
+    Priority => "priority",
+    Value => "value",
+    When => "when",
+    Alarm => "alarm",
+    Repeat => "repeat",
+    Done => "done",
+});
+
+string_enum!(TrashPolicy {
+    OnDemand => "on-demand",
+    OnClose => "on-close",
+    EndOfDay => "end-of-day",
+    Immediate => "immediate",
+});
+
+string_enum!(DonePolicy {
+    Keep => "keep",
+    Trash => "trash",
+});
+
+string_enum!(DateOrder {
+    YearMonthDay => "ymd",
+    MonthDayYear => "mdy",
+    DayMonthYear => "dmy",
+});
+
+string_enum!(WeekStart {
+    Monday => "monday",
+    Sunday => "sunday",
+});