serdeconv 0.4.1

use serde::{Deserialize, Serialize};
use serde_json;
use std::fs::File;
use std::io::{Read, Write};
use std::path::Path;

use {Error, Result};

/// Converts from the JSON file to a value of `T` type.
pub fn from_json_file<T, P>(path: P) -> Result<T>
where
    T: for<'a> Deserialize<'a>,
    P: AsRef<Path>,
{
    let f = track!(File::open(path).map_err(Error::from))?;
    track!(from_json_reader(f))
}

/// Reads a JSON string from the reader and converts it to a value of `T` type.
pub fn from_json_reader<T, R>(reader: R) -> Result<T>
where
    T: for<'a> Deserialize<'a>,
    R: Read,
{
    let value = track!(serde_json::from_reader(reader).map_err(Error::from))?;
    Ok(value)
}

/// Converts from the JSON string to a value of `T` type.
pub fn from_json_str<'a, T>(json: &'a str) -> Result<T>
where
    T: Deserialize<'a>,
{
    let value = track!(serde_json::from_str(json).map_err(Error::from))?;
    Ok(value)
}

/// Converts from the JSON bytes to a value of `T` type.
pub fn from_json_slice<'a, T>(json: &'a [u8]) -> Result<T>
where
    T: Deserialize<'a>,
{
    let value = track!(serde_json::from_slice(json).map_err(Error::from))?;
    Ok(value)
}

/// Converts the value to a JSON string and writes it to the speficied file.
pub fn to_json_file<T, P>(value: &T, path: P) -> Result<()>
where
    T: ?Sized + Serialize,
    P: AsRef<Path>,
{
    let f = track!(File::create(path).map_err(Error::from))?;
    track!(to_json_writer(value, f))
}

/// Converts the value to a JSON string and writes it to the writer.
pub fn to_json_writer<T, W>(value: &T, writer: W) -> Result<()>
where
    T: ?Sized + Serialize,
    W: Write,
{
    track!(serde_json::to_writer(writer, value).map_err(Error::from))?;
    Ok(())
}

/// Converts the value to a pretty printed JSON string and writes it to the writer.
pub fn to_json_writer_pretty<T, W>(value: &T, writer: W) -> Result<()>
where
    T: ?Sized + Serialize,
    W: Write,
{
    track!(serde_json::to_writer_pretty(writer, value).map_err(Error::from,))?;
    Ok(())
}

/// Converts the value to a JSON string.
pub fn to_json_string<T>(value: &T) -> Result<String>
where
    T: ?Sized + Serialize,
{
    let json = track!(serde_json::to_string(value).map_err(Error::from))?;
    Ok(json)
}

/// Converts the value to a pretty printed JSON string.
pub fn to_json_string_pretty<T>(value: &T) -> Result<String>
where
    T: ?Sized + Serialize,
{
    let json = track!(serde_json::to_string_pretty(value).map_err(Error::from))?;
    Ok(json)
}