1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145

//  You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
//  Unless required by applicable law or agreed to in writing, software
//  distributed under the License is distributed on an "AS IS" BASIS,
//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//  See the License for the specific language governing permissions and
//  limitations under the License.
//! Flags contains code for converting a UCG Val into the json output target.
use std;
use std::error::Error;
use std::io::Write;
use std::rc::Rc;

use serde_json;

use crate::build::Val;
use crate::convert::traits::{ConvertResult, Converter, ImportResult, Importer};

/// JsonConverter implements the logic for converting a Val into the json output format.
pub struct JsonConverter {}

impl JsonConverter {
    pub fn new() -> Self {
        JsonConverter {}
    }

    fn convert_list(&self, items: &Vec<Rc<Val>>) -> std::io::Result<serde_json::Value> {
        let mut v = Vec::new();
        for val in items.iter() {
            v.push(self.convert_value(val)?);
        }
        Ok(serde_json::Value::Array(v))
    }

    fn convert_tuple(&self, items: &Vec<(String, Rc<Val>)>) -> std::io::Result<serde_json::Value> {
        let mut mp = serde_json::Map::new();
        for &(ref k, ref v) in items.iter() {
            mp.entry(k.clone()).or_insert(self.convert_value(v)?);
        }
        Ok(serde_json::Value::Object(mp))
    }

    fn convert_env(&self, items: &Vec<(String, String)>) -> std::io::Result<serde_json::Value> {
        let mut mp = serde_json::Map::new();
        for &(ref k, ref v) in items.iter() {
            mp.entry(k.clone())
                .or_insert(serde_json::Value::String(v.clone()));
        }
        Ok(serde_json::Value::Object(mp))
    }

    fn convert_value(&self, v: &Val) -> std::io::Result<serde_json::Value> {
        let jsn_val = match v {
            &Val::Boolean(b) => serde_json::Value::Bool(b),
            &Val::Empty => serde_json::Value::Null,
            &Val::Float(f) => {
                let n = match serde_json::Number::from_f64(f) {
                    Some(n) => n,
                    // In theory this should never happen. But on the off chance that it does...
                    None => panic!("Float is too large or Not a Number {}", f),
                };
                serde_json::Value::Number(n)
            }
            &Val::Int(i) => {
                let n = match serde_json::Number::from_f64(i as f64) {
                    Some(n) => n,
                    // In theory this should never happen. But on the off chance that it does...
                    None => panic!("Float is too large or Not a Number {}", i),
                };
                serde_json::Value::Number(n)
            }
            &Val::Str(ref s) => serde_json::Value::String(s.clone()),
            &Val::Func(_) => {
                eprintln!("Skipping func encoding as null...");
                serde_json::Value::Null
            }
            &Val::Module(_) => {
                eprintln!("Skipping module encoding as null...");
                serde_json::Value::Null
            }
            &Val::Env(ref fs) => self.convert_env(fs)?,
            &Val::List(ref l) => self.convert_list(l)?,
            &Val::Tuple(ref t) => self.convert_tuple(t)?,
        };
        Ok(jsn_val)
    }

    fn convert_json_val(&self, v: &serde_json::Value) -> std::result::Result<Val, Box<dyn Error>> {
        Ok(match v {
            serde_json::Value::String(s) => Val::Str(s.clone()),
            serde_json::Value::Number(n) => {
                if let Some(i) = n.as_i64() {
                    Val::Int(i)
                } else {
                    Val::Float(n.as_f64().expect("Number was not an int or a float!!"))
                }
            }
            serde_json::Value::Bool(b) => Val::Boolean(*b),
            serde_json::Value::Null => Val::Empty,
            serde_json::Value::Array(l) => {
                let mut vs = Vec::with_capacity(l.len());
                for aval in l {
                    vs.push(Rc::new(self.convert_json_val(aval)?));
                }
                Val::List(vs)
            }
            serde_json::Value::Object(m) => {
                let mut fs = Vec::with_capacity(m.len());
                for (key, value) in m {
                    fs.push((key.to_string(), Rc::new(self.convert_json_val(value)?)));
                }
                Val::Tuple(fs)
            }
        })
    }

    fn write(&self, v: &Val, w: &mut Write) -> ConvertResult {
        let jsn_val = self.convert_value(v)?;
        serde_json::to_writer_pretty(w, &jsn_val)?;
        Ok(())
    }
}

impl Converter for JsonConverter {
    fn convert(&self, v: Rc<Val>, mut w: &mut Write) -> ConvertResult {
        self.write(&v, &mut w)
    }

    fn file_ext(&self) -> String {
        String::from("json")
    }

    fn description(&self) -> String {
        "Convert ucg Vals into valid json.".to_string()
    }
}

impl Importer for JsonConverter {
    fn import(&self, bytes: &[u8]) -> ImportResult {
        let json_val = serde_json::from_slice(bytes)?;
        Ok(Rc::new(self.convert_json_val(&json_val)?))
    }
}