terminal: single pagelist node search

src/terminal/main.zig

@@ -18,6 +18,7 @@ pub const kitty = @import("kitty.zig");
 pub const modes = @import("modes.zig");
 pub const page = @import("page.zig");
 pub const parse_table = @import("parse_table.zig");
+pub const search = @import("search.zig");
 pub const size = @import("size.zig");
 pub const tmux = @import("tmux.zig");
 pub const x11_color = @import("x11_color.zig");

src/terminal/search.zig

@@ -0,0 +1,148 @@
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const assert = std.debug.assert;
+const terminal = @import("main.zig");
+const point = terminal.point;
+const Page = terminal.Page;
+const PageList = terminal.PageList;
+const Selection = terminal.Selection;
+const Screen = terminal.Screen;
+
+pub const PageSearch = struct {
+    alloc: Allocator,
+    node: *PageList.List.Node,
+    needle: []const u8,
+    cell_map: Page.CellMap,
+    encoded: std.ArrayListUnmanaged(u8) = .{},
+    i: usize = 0,
+
+    pub fn init(
+        alloc: Allocator,
+        node: *PageList.List.Node,
+        needle: []const u8,
+    ) !PageSearch {
+        var result: PageSearch = .{
+            .alloc = alloc,
+            .node = node,
+            .needle = needle,
+            .cell_map = Page.CellMap.init(alloc),
+        };
+
+        const page: *const Page = &node.data;
+        _ = try page.encodeUtf8(result.encoded.writer(alloc), .{
+            .cell_map = &result.cell_map,
+        });
+
+        return result;
+    }
+
+    pub fn deinit(self: *PageSearch) void {
+        self.encoded.deinit(self.alloc);
+        self.cell_map.deinit();
+    }
+
+    pub fn next(self: *PageSearch) ?Selection {
+        // Search our haystack for the needle. The resulting index is
+        // the offset from self.i not the absolute index.
+        const haystack: []const u8 = self.encoded.items[self.i..];
+        const i_offset = std.mem.indexOf(u8, haystack, self.needle) orelse {
+            self.i = self.encoded.items.len;
+            return null;
+        };
+
+        // Get our full index into the encoded buffer.
+        const idx = self.i + i_offset;
+
+        // We found our search term. Move the cursor forward one beyond
+        // the match. This lets us find every repeated match.
+        self.i = idx + 1;
+
+        const tl: PageList.Pin = tl: {
+            const map = self.cell_map.items[idx];
+            break :tl .{
+                .node = self.node,
+                .y = map.y,
+                .x = map.x,
+            };
+        };
+        const br: PageList.Pin = br: {
+            const map = self.cell_map.items[idx + self.needle.len - 1];
+            break :br .{
+                .node = self.node,
+                .y = map.y,
+                .x = map.x,
+            };
+        };
+
+        return Selection.init(tl, br, false);
+    }
+};
+
+test "search single page one match" {
+    const testing = std.testing;
+    const alloc = testing.allocator;
+
+    var s = try Screen.init(alloc, 80, 24, 0);
+    defer s.deinit();
+    try s.testWriteString("hello, world");
+
+    // We want to test single-page cases.
+    try testing.expect(s.pages.pages.first == s.pages.pages.last);
+    const node: *PageList.List.Node = s.pages.pages.first.?;
+
+    var it = try PageSearch.init(alloc, node, "world");
+    defer it.deinit();
+
+    const sel = it.next().?;
+    try testing.expectEqual(point.Point{ .active = .{
+        .x = 7,
+        .y = 0,
+    } }, s.pages.pointFromPin(.active, sel.start()).?);
+    try testing.expectEqual(point.Point{ .active = .{
+        .x = 11,
+        .y = 0,
+    } }, s.pages.pointFromPin(.active, sel.end()).?);
+
+    try testing.expect(it.next() == null);
+}
+
+test "search single page multiple match" {
+    const testing = std.testing;
+    const alloc = testing.allocator;
+
+    var s = try Screen.init(alloc, 80, 24, 0);
+    defer s.deinit();
+    try s.testWriteString("hello. boo! hello. boo!");
+
+    // We want to test single-page cases.
+    try testing.expect(s.pages.pages.first == s.pages.pages.last);
+    const node: *PageList.List.Node = s.pages.pages.first.?;
+
+    var it = try PageSearch.init(alloc, node, "boo!");
+    defer it.deinit();
+
+    {
+        const sel = it.next().?;
+        try testing.expectEqual(point.Point{ .active = .{
+            .x = 7,
+            .y = 0,
+        } }, s.pages.pointFromPin(.active, sel.start()).?);
+        try testing.expectEqual(point.Point{ .active = .{
+            .x = 10,
+            .y = 0,
+        } }, s.pages.pointFromPin(.active, sel.end()).?);
+    }
+    {
+        const sel = it.next().?;
+        try testing.expectEqual(point.Point{ .active = .{
+            .x = 19,
+            .y = 0,
+        } }, s.pages.pointFromPin(.active, sel.start()).?);
+        try testing.expectEqual(point.Point{ .active = .{
+            .x = 22,
+            .y = 0,
+        } }, s.pages.pointFromPin(.active, sel.end()).?);
+    }
+
+    try testing.expect(it.next() == null);
+}