//! demo: token attribute extraction and parser state machine transitions.

const std = @import("std");
const spacez = @import("spacez");

pub fn main() !void {
    const print = std.debug.print;

    // demo: extract token attributes
    const tokens = [_][]const u8{ "Barack", "Obama", "visited", "Paris" };

    print("spacez token attributes:\n", .{});
    for (tokens) |token| {
        const attrs = spacez.extractAttrs(token);
        var shape_buf: [64]u8 = undefined;
        const shape = spacez.computeShape(token, &shape_buf);
        print("  {s:>10}  norm={x:0>16}  shape={s}\n", .{
            token, attrs.norm, shape,
        });
    }

    // demo: parser state machine (without model weights, just show transitions)
    print("\nparser state machine demo:\n", .{});
    var state = spacez.parser.State.init(4);

    const actions = [_]struct { a: spacez.parser.Action, l: ?spacez.Label }{
        .{ .a = .BEGIN, .l = .PERSON },
        .{ .a = .LAST, .l = .PERSON },
        .{ .a = .OUT, .l = null },
        .{ .a = .UNIT, .l = .GPE },
    };

    for (actions, 0..) |act, i| {
        const valid = state.isValid(act.a, act.l);
        print("  step {d}: {s}-{s} valid={}\n", .{
            i,
            @tagName(act.a),
            if (act.l) |l| @tagName(l) else "(none)",
            valid,
        });
        if (valid) state.apply(act.a, act.l);
    }

    print("\nentities found:\n", .{});
    for (state.entities()) |e| {
        print("  [{d}..{d}) {s}\n", .{ e.start, e.end, @tagName(e.label) });
    }
}