const std = @import("std");
const tokens = @import("tokens.zig");
const Token = tokens.Token;

pub const NodeList = std.ArrayList(*Node);
pub const ParamList = std.ArrayList(*ParamDecl);

// TODO convert FnCall to something like PrefixOp / InfixOp / SuffixOp
pub const NodeType = enum {
    Root,
    FnDecl,
    FnCall,
    String,
};

pub const ParamDecl = struct {
    param_name: Token,

    // TODO types
    param_type: Token,
};

pub const FnDecl = struct {
    func_name: Token,
    params: ParamList,
    body: NodeList,
};

pub const FnCall = struct {
    func_name: Token,
    arguments: NodeList,
};

pub const Node = union(NodeType) {
    Root: NodeList,
    FnDecl: FnDecl,
    FnCall: FnCall,
    String: Token,
};

pub fn mkRoot(allocator: *std.mem.Allocator) !*Node {
    var node = try allocator.create(Node);
    node.* = Node{ .Root = NodeList.init(allocator) };
    return node;
}

fn print(ident: usize, comptime fmt: []const u8, args: ...) void {
    var i: usize = 0;
    while (i < ident) : (i += 1) {
        std.debug.warn("\t");
    }

    std.debug.warn(fmt, args);
}

pub fn printNode(node: *Node, ident: usize) void {
    switch (node.*) {
        .FnDecl => |proto| {
            print(ident, "FnDecl name='{}'\n", proto.func_name.lexeme);
        },
        .Root => {
            for (node.Root.toSlice()) |child| {
                printNode(child, ident + 1);
            }
        },
        else => {
            print(ident, "unknown node: {}\n", node);
        },
    }
}