1 files changed, 130 insertions, 0 deletions
diff --git a/src/app/state.rs b/src/app/state.rs
new file mode 100644
index 00000000..b0a81165
--- /dev/null
+++ b/src/app/state.rs
@@ -0,0 +1,130 @@
+use crossterm::event::{KeyCode, KeyModifiers};
+use crate::config::Keybinds;
+use ratatui::layout::{Direction, Rect};
+use ratatui::style::Color;
+
+use crate::layout::{PaneInfo, SplitBorder};
+use crate::selection::Selection;
+use crate::workspace::Workspace;
+
+/// Computed view geometry — derived from AppState + terminal size.
+/// Updated before each render, consumed by render and mouse handling.
+pub struct ViewState {
+    pub sidebar_rect: Rect,
+    pub terminal_area: Rect,
+    pub pane_infos: Vec<PaneInfo>,
+    pub split_borders: Vec<SplitBorder>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Mode {
+    Navigate,
+    Terminal,
+    CreateSession,
+    RenameSession,
+    Resize,
+    ConfirmClose,
+    ContextMenu,
+}
+
+/// Active mouse drag on a split border.
+pub(crate) struct DragState {
+    pub path: Vec<bool>,
+    pub direction: Direction,
+    pub area: Rect,
+}
+
+/// Right-click context menu state.
+pub struct ContextMenuState {
+    pub ws_idx: usize,
+    pub x: u16,
+    pub y: u16,
+    pub selected: usize,
+}
+
+pub const CONTEXT_MENU_ITEMS: &[&str] = &["Rename", "Close"];
+
+/// All application state — pure data, no channels or async runtime.
+/// Testable without PTYs or a tokio runtime.
+pub struct AppState {
+    pub workspaces: Vec<Workspace>,
+    pub active: Option<usize>,
+    pub selected: usize,
+    pub mode: Mode,
+    pub should_quit: bool,
+    pub name_input: String,
+    // View geometry (computed before render, consumed by render + mouse)
+    pub view: ViewState,
+    pub(crate) drag: Option<DragState>,
+    pub selection: Option<Selection>,
+    pub context_menu: Option<ContextMenuState>,
+    // Update notification
+    pub update_available: Option<String>,
+    pub update_dismissed: bool,
+    // Config
+    pub prefix_code: KeyCode,
+    pub prefix_mods: KeyModifiers,
+    pub prefix_label: String,
+    pub sidebar_width: u16,
+    pub sidebar_collapsed: bool,
+    pub confirm_close: bool,
+    pub accent: Color,
+    pub keybinds: Keybinds,
+}
+
+impl AppState {
+    pub fn is_prefix(&self, key: &crossterm::event::KeyEvent) -> bool {
+        key.code == self.prefix_code && key.modifiers.contains(self.prefix_mods)
+    }
+
+    pub fn estimate_pane_size(&self) -> (u16, u16) {
+        if let Some(info) = self.view.pane_infos.first() {
+            (info.rect.height, info.rect.width)
+        } else {
+            (24, 80)
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+// Test helpers
+// ---------------------------------------------------------------------------
+
+#[cfg(test)]
+impl AppState {
+    /// Create an AppState for testing — no channels, no PTYs.
+    pub fn test_new() -> Self {
+        Self {
+            workspaces: Vec::new(),
+            active: None,
+            selected: 0,
+            mode: Mode::Navigate,
+            should_quit: false,
+            name_input: String::new(),
+            view: ViewState {
+                sidebar_rect: Rect::default(),
+                terminal_area: Rect::default(),
+                pane_infos: Vec::new(),
+                split_borders: Vec::new(),
+            },
+            drag: None,
+            selection: None,
+            context_menu: None,
+            update_available: None,
+            update_dismissed: false,
+            prefix_code: KeyCode::Char('s'),
+            prefix_mods: KeyModifiers::CONTROL,
+            prefix_label: "ctrl+s".into(),
+            sidebar_width: 26,
+            sidebar_collapsed: false,
+            confirm_close: true,
+            accent: Color::Cyan,
+            keybinds: Keybinds {
+                split_vertical: (KeyCode::Char('v'), KeyModifiers::empty()),
+                split_horizontal: (KeyCode::Char('-'), KeyModifiers::empty()),
+                close_pane: (KeyCode::Char('x'), KeyModifiers::empty()),
+                fullscreen: (KeyCode::Char('f'), KeyModifiers::empty()),
+            },
+        }
+    }
+}