feat: add conditional styles for sidebar tokens (#3693)

2 files changed, 21 insertions, 2 deletions

diff --git a/docs/next/website/src/content/docs/configuration.mdx b/docs/next/website/src/content/docs/configuration.mdx
index 63ce3186..0f4b58fb 100644
--- a/docs/next/website/src/content/docs/configuration.mdx
+++ b/docs/next/website/src/content/docs/configuration.mdx
@@ -400,6 +400,25 @@ rows = [
 
 `fg` accepts strict `#RGB` or `#RRGGBB`. `bold` and `dim` accept booleans. Omitted fields preserve the token's contextual style; explicit `false` removes that modifier. Styling applies to one occurrence, so the same token may look different in another row or agent override. A foreground override replaces all semantic foregrounds inside that occurrence: for example, styled `git_status` ahead and behind counts use one color instead of their default green and red. Token styles never change separators or row backgrounds.
 
+Text-valued tokens also accept up to 16 ordered `rules`. Each rule contains exactly one condition—`equals`, `contains`, `starts_with`, `gt`, or `lt`—and optional `fg`, `bold`, and `dim` overrides:
+
+```toml
+[ui.sidebar.agents]
+rows = [
+  ["state_icon", "workspace", "tab"],
+  [{ token = "machine", fg = "#fff", rules = [{ equals = "Local", fg = "#f55" }, { equals = "Fedora", ignore_case = true, fg = "#51a2da" }] }, "agent"],
+  [{ token = "$load", fg = "#fff", rules = [{ gt = 80, fg = "#f55", bold = true }, { gt = 50, fg = "#fc0" }] }],
+]
+```
+
+The first matching rule wins. Its specified style fields override the occurrence's defaults; unspecified fields inherit them. If no rule matches, the defaults remain. Matching uses the full token value before display truncation and does not change its text, separators, or visibility. A rule with no style fields stops matching and keeps the defaults.
+
+`equals`, `contains`, and `starts_with` take strings and are case-sensitive. Add `ignore_case = true` for ASCII case-insensitive matching; non-ASCII characters remain case-sensitive. Empty strings follow ordinary string matching: empty `equals` matches only an empty value, while empty `contains` or `starts_with` matches any present value.
+
+`gt` and `lt` take finite numeric thresholds and compare strictly greater or less, not equal. Values must parse completely as finite numbers; decimal and exponent forms work, but whitespace, units, `NaN`, and infinity do not match. `ignore_case` is not accepted on numeric rules. Comparisons use floating-point numbers, not exact large-integer arithmetic.
+
+Rules work with text-valued built-ins and custom `$name` tokens in Agent rows, `rows_by_agent` overrides, and Space rows. Custom tokens match their reported value: `$load` reporting `"90"` selects red and bold above, `"60"` selects yellow, and `"90%"` keeps white. Unreported tokens still disappear. `state_icon` and composite `git_status` accept fixed styles only, not rules. Unknown conditions and malformed rules are rejected when loading config; regex, fuzzy matching, and scripts are not supported.
+
 `row_gap` controls the blank terminal rows between entries, independently for the Agent and Space panels. It defaults to `0`, which packs entries together; set it to `1` to restore the previous spacing. It does not add spacing between the content lines declared in `rows`. Consecutive indented worktree children remain packed as one Space group.
 
 Override the complete Agent layout for a known agent under `rows_by_agent`:
diff --git a/docs/next/website/src/data/config-reference.json b/docs/next/website/src/data/config-reference.json
index 990509b2..ea04a2cc 100644
--- a/docs/next/website/src/data/config-reference.json
+++ b/docs/next/website/src/data/config-reference.json
@@ -1053,7 +1053,7 @@
           "key": "ui.sidebar.agents.rows",
           "type": "list of token rows",
           "default": "[[\"state_icon\", \"workspace\", \"tab\"], [\"agent\"]]",
-          "description": "Default expanded Agent sidebar layout. Entries may be token strings or inline { token, fg, bold, dim } style tables. Supports built-in and $name metadata tokens; at most 16 rows and 16 tokens per row."
+          "description": "Default expanded Agent sidebar layout. Entries may be token strings or inline { token, fg, bold, dim, rules } style tables. Text-valued built-ins and $name metadata tokens accept up to 16 ordered rules using equals, contains, starts_with, gt, or lt; the first match overrides specified styles. Text conditions optionally accept ignore_case for ASCII matching; numeric conditions require full finite numbers. state_icon accepts fixed styles only. At most 16 rows and 16 tokens per row."
         },
         {
           "key": "ui.sidebar.agents.rows_by_agent",
@@ -1071,7 +1071,7 @@
           "key": "ui.sidebar.spaces.rows",
           "type": "list of token rows",
           "default": "[[\"state_icon\", \"workspace\"], [\"branch\", \"git_status\"]]",
-          "description": "Expanded Space sidebar layout. Entries may be token strings or inline { token, fg, bold, dim } style tables. Supports built-in and $name metadata tokens; at most 16 rows and 16 tokens per row."
+          "description": "Expanded Space sidebar layout. Entries may be token strings or inline { token, fg, bold, dim, rules } style tables. Text-valued built-ins and $name metadata tokens accept up to 16 ordered rules using equals, contains, starts_with, gt, or lt; the first match overrides specified styles. Text conditions optionally accept ignore_case for ASCII matching; numeric conditions require full finite numbers. state_icon and git_status accept fixed styles only. At most 16 rows and 16 tokens per row."
         },
         {
           "key": "ui.accent",