scritcher/src/lang.zig

115 lines
3.2 KiB
Zig

const std = @import("std");
pub const ParseError = error{
NoCommandGiven,
UnknownCommand,
ArgRequired,
};
pub const CommandType = enum {
Noop,
Load,
Amp,
RFlanger,
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 {
// TODO make a hashmap for those
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, "rflanger")) {
return CommandType.RFlanger;
} 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