use std::default::Default;
use std::str::FromStr;
use serialize;
use {ByteString, CsvResult, Error};
pub struct Decoded {
stack: Vec<ByteString>,
popped: uint,
}
impl Decoded {
pub fn new(mut bytes: Vec<ByteString>) -> Decoded {
bytes.reverse();
Decoded { stack: bytes, popped: 0 }
}
fn len(&self) -> uint {
self.stack.len()
}
}
impl Decoded {
fn pop(&mut self) -> CsvResult<ByteString> {
self.popped += 1;
match self.stack.pop() {
None => self.err(format!(
"Expected a record with length at least {}, \
but got a record with length {}.",
self.popped, self.popped - 1)),
Some(bytes) => Ok(bytes),
}
}
fn pop_string(&mut self) -> CsvResult<String> {
{try!(self.pop())}.into_utf8_string().map_err(|bytes| {
Error::Decode(
format!("Could not convert bytes '{}' to UTF-8.", bytes))
})
}
fn pop_from_str<T: FromStr + Default>(&mut self) -> CsvResult<T> {
let s = try!(self.pop_string());
let s = s.as_slice().trim();
match FromStr::from_str(s) {
Some(t) => Ok(t),
None => self.err(format!("Failed converting '{}' from str.", s)),
}
}
fn push(&mut self, s: ByteString) {
self.stack.push(s);
}
fn push_string(&mut self, s: String) {
self.push(ByteString::from_bytes(s.into_bytes()));
}
fn err<T, S: StrAllocating>(&self, msg: S) -> CsvResult<T> {
Err(Error::Decode(msg.into_string()))
}
}
impl serialize::Decoder<Error> for Decoded {
fn error(&mut self, err: &str) -> Error {
Error::Decode(err.into_string())
}
fn read_nil(&mut self) -> CsvResult<()> { unimplemented!() }
fn read_uint(&mut self) -> CsvResult<uint> { self.pop_from_str() }
fn read_u64(&mut self) -> CsvResult<u64> { self.pop_from_str() }
fn read_u32(&mut self) -> CsvResult<u32> { self.pop_from_str() }
fn read_u16(&mut self) -> CsvResult<u16> { self.pop_from_str() }
fn read_u8(&mut self) -> CsvResult<u8> { self.pop_from_str() }
fn read_int(&mut self) -> CsvResult<int> { self.pop_from_str() }
fn read_i64(&mut self) -> CsvResult<i64> { self.pop_from_str() }
fn read_i32(&mut self) -> CsvResult<i32> { self.pop_from_str() }
fn read_i16(&mut self) -> CsvResult<i16> { self.pop_from_str() }
fn read_i8(&mut self) -> CsvResult<i8> { self.pop_from_str() }
fn read_bool(&mut self) -> CsvResult<bool> { self.pop_from_str() }
fn read_f64(&mut self) -> CsvResult<f64> { self.pop_from_str() }
fn read_f32(&mut self) -> CsvResult<f32> { self.pop_from_str() }
fn read_char(&mut self) -> CsvResult<char> {
let s = try!(self.pop_string());
let chars: Vec<char> = s.as_slice().chars().collect();
if chars.len() != 1 {
return self.err(format!(
"Expected single character but got '{}'.", s))
}
Ok(chars[0])
}
fn read_str(&mut self) -> CsvResult<String> {
self.pop_string()
}
fn read_enum<T, F>(&mut self, _: &str, f: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
f(self)
}
fn read_enum_variant<T, F>(&mut self, names: &[&str], f: F)
-> CsvResult<T>
where F: FnOnce(&mut Decoded, uint) -> CsvResult<T> {
let variant = to_lower(try!(self.pop_string()).as_slice());
match names.iter().position(|&name| to_lower(name) == variant) {
Some(idx) => f(self, idx),
None => self.err(format!(
"Could not match '{}' with any of the variants: {}",
variant, names)),
}
}
fn read_enum_variant_arg<T, F>(&mut self, _: uint, f: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
f(self)
}
fn read_enum_struct_variant<T, F>(&mut self, names: &[&str], f: F)
-> CsvResult<T>
where F: FnOnce(&mut Decoded, uint) -> CsvResult<T> {
self.read_enum_variant(names, f)
}
fn read_enum_struct_variant_field<T, F>(&mut self, _: &str,
f_idx: uint, f: F)
-> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
self.read_enum_variant_arg(f_idx, f)
}
fn read_struct<T, F>(&mut self, s_name: &str, len: uint, f: F)
-> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
if self.len() < len {
return self.err(
format!("Struct '{}' has {} fields but current record \
has {} fields.", s_name, len, self.len()));
}
f(self)
}
fn read_struct_field<T, F>(&mut self, _: &str, _: uint, f: F)
-> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
f(self)
}
fn read_tuple<T, F>(&mut self, _: uint, f: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
f(self)
}
fn read_tuple_arg<T, F>(&mut self, _: uint, f: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
f(self)
}
fn read_tuple_struct<T, F>(&mut self, _: &str, _: uint, _: F)
-> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
unimplemented!()
}
fn read_tuple_struct_arg<T, F>(&mut self, _: uint, _: F)
-> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
unimplemented!()
}
fn read_option<T, F>(&mut self, f: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded, bool) -> CsvResult<T> {
let s = try!(self.pop_string());
if s.is_empty() {
f(self, false)
} else {
self.push_string(s);
f(self, true)
}
}
fn read_seq<T, F>(&mut self, f: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded, uint) -> CsvResult<T> {
let len = self.len();
f(self, len)
}
fn read_seq_elt<T, F>(&mut self, _: uint, f: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
f(self)
}
fn read_map<T, F>(&mut self, _: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded, uint) -> CsvResult<T> {
unimplemented!()
}
fn read_map_elt_key<T, F>(&mut self, _: uint, _: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
unimplemented!()
}
fn read_map_elt_val<T, F>(&mut self, _: uint, _: F) -> CsvResult<T>
where F: FnOnce(&mut Decoded) -> CsvResult<T> {
unimplemented!()
}
}
fn to_lower(s: &str) -> String {
s.chars().map(|c| c.to_lowercase()).collect()
}