path: root/src/ser.rs

use serde::ser;
use std::fmt::Display;
use std::mem;

use error::*;
use value::{Value, ValueKind};
use Config;

#[derive(Default, Debug)]
pub struct ConfigSerializer {
    keys: Vec<(String, Option<usize>)>,
    pub output: Config,
}

impl ConfigSerializer {
    fn serialize_primitive<T>(&mut self, value: T) -> Result<()>
    where
        T: Into<Value> + Display,
    {
        let key = match self.last_key_index_pair() {
            Some((key, Some(index))) => format!("{}[{}]", key, index),
            Some((key, None)) => key.to_string(),
            None => {
                return Err(ConfigError::Message(format!(
                    "key is not found for value {}",
                    value
                )))
            }
        };
        self.output.set(&key, value.into())?;
        Ok(())
    }

    fn last_key_index_pair(&self) -> Option<(&str, Option<usize>)> {
        let len = self.keys.len();
        if len > 0 {
            self.keys
                .get(len - 1)
                .map(|&(ref key, opt)| (key.as_str(), opt))
        } else {
            None
        }
    }

    fn inc_last_key_index(&mut self) -> Result<()> {
        let len = self.keys.len();
        if len > 0 {
            self.keys
                .get_mut(len - 1)
                .map(|pair| pair.1 = pair.1.map(|i| i + 1).or(Some(0)))
                .ok_or_else(|| {
                    ConfigError::Message(format!("last key is not found in {} keys", len))
                })
        } else {
            Err(ConfigError::Message("keys is empty".to_string()))
        }
    }

    fn make_full_key(&self, key: &str) -> String {
        let len = self.keys.len();
        if len > 0 {
            if let Some(&(ref prev_key, index)) = self.keys.get(len - 1) {
                return if let Some(index) = index {
                    format!("{}[{}].{}", prev_key, index, key)
                } else {
                    format!("{}.{}", prev_key, key)
                };
            }
        }
        key.to_string()
    }

    fn push_key(&mut self, key: &str) {
        let full_key = self.make_full_key(key);
        self.keys.push((full_key, None));
    }

    fn pop_key(&mut self) -> Option<(String, Option<usize>)> {
        self.keys.pop()
    }
}

impl<'a> ser::Serializer for &'a mut ConfigSerializer {
    type Ok = ();
    type Error = ConfigError;
    type SerializeSeq = Self;
    type SerializeTuple = Self;
    type SerializeTupleStruct = Self;
    type SerializeTupleVariant = Self;
    type SerializeMap = Self;
    type SerializeStruct = Self;
    type SerializeStructVariant = Self;

    fn serialize_bool(self, v: bool) -> Result<Self::Ok> {
        self.serialize_primitive(v)
    }

    fn serialize_i8(self, v: i8) -> Result<Self::Ok> {
        self.serialize_i64(v as i64)
    }

    fn serialize_i16(self, v: i16) -> Result<Self::Ok> {
        self.serialize_i64(v as i64)
    }

    fn serialize_i32(self, v: i32) -> Result<Self::Ok> {
        self.serialize_i64(v as i64)
    }

    fn serialize_i64(self, v: i64) -> Result<Self::Ok> {
        self.serialize_primitive(v)
    }

    fn serialize_u8(self, v: u8) -> Result<Self::Ok> {
        self.serialize_u64(v as u64)
    }

    fn serialize_u16(self, v: u16) -> Result<Self::Ok> {
        self.serialize_u64(v as u64)
    }

    fn serialize_u32(self, v: u32) -> Result<Self::Ok> {
        self.serialize_u64(v as u64)
    }

    fn serialize_u64(self, v: u64) -> Result<Self::Ok> {
        if v > (i64::max_value() as u64) {
            Err(ConfigError::Message(format!(
                "value {} is greater than the max {}",
                v,
                i64::max_value()
            )))
        } else {
            self.serialize_i64(v as i64)
        }
    }

    fn serialize_f32(self, v: f32) -> Result<Self::Ok> {
        self.serialize_f64(v as f64)
    }

    fn serialize_f64(self, v: f64) -> Result<Self::Ok> {
        self.serialize_primitive(v)
    }

    fn serialize_char(self, v: char) -> Result<Self::Ok> {
        self.serialize_primitive(v.to_string())
    }

    fn serialize_str(self, v: &str) -> Result<Self::Ok> {
        self.serialize_primitive(v.to_string())
    }

    fn serialize_bytes(self, v: &[u8]) -> Result<Self::Ok> {
        use serde::ser::SerializeSeq;
        let mut seq = self.serialize_seq(Some(v.len()))?;
        for byte