implement array index filter

1 files changed, 32 insertions, 8 deletions

diff --git a/src/jq/tokenize.zig b/src/jq/tokenize.zig
index 0823ea1..92f96ca 100644
--- a/src/jq/tokenize.zig
+++ b/src/jq/tokenize.zig
@@ -2,32 +2,56 @@ const std = @import("std");
 
 pub const TokenizeError = error{
     UnexpectedEnd,
+    InvalidCharacter,
 };
 
 pub const TokenKind = enum {
     end,
-    identity,
+    dot,
+    bracket_left,
+    bracket_right,
+    number,
 };
 
-pub const Token = struct {
-    kind: TokenKind,
+pub const Token = union(TokenKind) {
+    end,
+    dot,
+    bracket_left,
+    bracket_right,
+    number: i64,
+
+    pub fn kind(self: @This()) TokenKind {
+        return self;
+    }
 };
 
 pub fn tokenize(allocator: std.mem.Allocator, query: []const u8) ![]Token {
     var tokens = try std.array_list.Aligned(Token, null).initCapacity(allocator, 16);
 
     const len = query.len;
+
+    if (len == 0) {
+        return error.UnexpectedEnd;
+    }
+
     var i: usize = 0;
     while (i < len) {
         const c = query[i];
-        if (c == '.') {
-            try tokens.append(allocator, .{ .kind = .identity });
-        } else {
-            return TokenizeError.UnexpectedEnd;
+        switch (c) {
+            '.' => try tokens.append(allocator, .dot),
+            '[' => try tokens.append(allocator, .bracket_left),
+            ']' => try tokens.append(allocator, .bracket_right),
+            else => {
+                if (std.ascii.isDigit(c)) {
+                    try tokens.append(allocator, .{ .number = (c - '0') });
+                } else {
+                    return error.InvalidCharacter;
+                }
+            },
         }
         i += 1;
     }
 
-    try tokens.append(allocator, .{ .kind = .end });
+    try tokens.append(allocator, .end);
     return tokens.toOwnedSlice(allocator);
 }