const std = @import("std"); pub const ParseError = error{ NoCommandGiven, UnknownCommand, ArgRequired, }; pub const CommandType = enum { Noop, Load, Amp, Quicksave, }; pub const Command = struct { command: CommandType, args: ArgList, pub fn print(self: *const Command) void { std.debug.warn("cmd:{}\n", self.command); } pub fn argAt(self: *const Command, idx: usize) ![]const u8 { const args = self.args.toSliceConst(); if (idx > (args.len - 1)) { std.debug.warn("Expected argument at index {}\n", idx); return ParseError.ArgRequired; } return args[idx]; } pub fn usizeArgAt(self: *const Command, idx: usize) !usize { var arg = try self.argAt(idx); return try std.fmt.parseInt(usize, arg, 10); } pub fn intArgAt(self: *const Command, idx: usize) !i32 { var arg = try self.argAt(idx); return try std.fmt.parseInt(i32, arg, 10); } pub fn floatArgAt(self: *const Command, idx: usize) !f32 { var arg = try self.argAt(idx); return try std.fmt.parseFloat(f32, arg); } }; pub const CommandList = std.ArrayList(*Command); pub const ArgList = std.ArrayList([]const u8); pub fn commandToCmdType(command: []const u8) ParseError!CommandType { if (std.mem.eql(u8, command, "noop")) { return CommandType.Noop; } else if (std.mem.eql(u8, command, "load")) { return CommandType.Load; } else if (std.mem.eql(u8, command, "amp")) { return CommandType.Amp; } else if (std.mem.eql(u8, command, "quicksave")) { return CommandType.Quicksave; } else { std.debug.warn("Unknown command: '{}'\n", command); return ParseError.UnknownCommand; } } pub const Lang = struct { allocator: *std.mem.Allocator, pub fn init(allocator: *std.mem.Allocator) Lang { return Lang{ .allocator = allocator }; } pub fn parse(self: *Lang, data: []const u8) !CommandList { var splitted_it = std.mem.separate(data, ";"); var cmds = CommandList.init(self.allocator); while (splitted_it.next()) |stmt_orig| { var stmt = std.mem.trimRight(u8, stmt_orig, "\n"); stmt = std.mem.trimLeft(u8, stmt, "\n"); if (stmt.len == 0) continue; if (stmt[0] == '#') continue; // TODO better tokenizer instead of just tokenize(" "); var tok_it = std.mem.tokenize(stmt, " "); var cmd_opt = tok_it.next(); if (cmd_opt == null) return ParseError.NoCommandGiven; var command = cmd_opt.?; var ctype = try commandToCmdType(command); var args = ArgList.init(self.allocator); while (tok_it.next()) |arg| { try args.append(arg); } // construct final Command based on command var cmd_ptr = try self.allocator.create(Command); cmd_ptr.* = Command{ .command = ctype, .args = args }; try cmds.append(cmd_ptr); } return cmds; } }; // TODO tests