/*
 * This file is part of espanso.
 *
 * Copyright (C) 2019-2021 Federico Terzi
 *
 * espanso is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * espanso is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
 */

use std::convert::TryInto;

use anyhow::Result;
use serde_yaml::Mapping;
use thiserror::Error;

use crate::matches::{Number, Params, Value};

pub(crate) fn convert_params(m: Mapping) -> Result<Params> {
  let mut params = Params::new();

  for (key, value) in m {
    let key = key.as_str().ok_or(ConversionError::InvalidKeyFormat)?;
    let value = convert_value(value)?;
    params.insert(key.to_owned(), value);
  }

  Ok(params)
}

fn convert_value(value: serde_yaml::Value) -> Result<Value> {
  Ok(match value {
    serde_yaml::Value::Null => Value::Null,
    serde_yaml::Value::Bool(val) => Value::Bool(val),
    serde_yaml::Value::Number(n) => {
      if n.is_i64() {
        Value::Number(Number::Integer(
          n.as_i64().ok_or(ConversionError::InvalidNumberFormat)?,
        ))
      } else if n.is_u64() {
        Value::Number(Number::Integer(
          n.as_u64()
            .ok_or(ConversionError::InvalidNumberFormat)?
            .try_into()?,
        ))
      } else if n.is_f64() {
        Value::Number(Number::Float(
          n.as_f64()
            .ok_or(ConversionError::InvalidNumberFormat)?
            .into(),
        ))
      } else {
        return Err(ConversionError::InvalidNumberFormat.into());
      }
    }
    serde_yaml::Value::String(s) => Value::String(s),
    serde_yaml::Value::Sequence(arr) => Value::Array(
      arr
        .into_iter()
        .map(convert_value)
        .collect::<Result<Vec<Value>>>()?,
    ),
    serde_yaml::Value::Mapping(m) => Value::Object(convert_params(m)?),
  })
}

#[derive(Error, Debug)]
pub enum ConversionError {
  #[error("invalid key format")]
  InvalidKeyFormat,

  #[error("invalid number format")]
  InvalidNumberFormat,
}

#[cfg(test)]
mod tests {
  use super::*;

  #[test]
  fn convert_value_null() {
    assert_eq!(convert_value(serde_yaml::Value::Null).unwrap(), Value::Null);
  }

  #[test]
  fn convert_value_bool() {
    assert_eq!(
      convert_value(serde_yaml::Value::Bool(true)).unwrap(),
      Value::Bool(true)
    );
    assert_eq!(
      convert_value(serde_yaml::Value::Bool(false)).unwrap(),
      Value::Bool(false)
    );
  }

  #[test]
  fn convert_value_number() {
    assert_eq!(
      convert_value(serde_yaml::Value::Number(0.into())).unwrap(),
      Value::Number(Number::Integer(0))
    );
    assert_eq!(
      convert_value(serde_yaml::Value::Number((-100).into())).unwrap(),
      Value::Number(Number::Integer(-100))
    );
    assert_eq!(
      convert_value(serde_yaml::Value::Number(1.5.into())).unwrap(),
      Value::Number(Number::Float(1.5.into()))
    );
  }
  #[test]
  fn convert_value_string() {
    assert_eq!(
      convert_value(serde_yaml::Value::String("hello".to_string())).unwrap(),
      Value::String("hello".to_string())
    );
  }
  #[test]
  fn convert_value_array() {
    assert_eq!(
      convert_value(serde_yaml::Value::Sequence(vec![
        serde_yaml::Value::Bool(true),
        serde_yaml::Value::Null,
      ]))
      .unwrap(),
      Value::Array(vec![Value::Bool(true), Value::Null,])
    );
  }

  #[test]
  fn convert_value_params() {
    let mut mapping = serde_yaml::Mapping::new();
    mapping.insert(
      serde_yaml::Value::String("test".to_string()),
      serde_yaml::Value::Null,
    );

    let mut expected = Params::new();
    expected.insert("test".to_string(), Value::Null);
    assert_eq!(
      convert_value(serde_yaml::Value::Mapping(mapping)).unwrap(),
      Value::Object(expected)
    );
  }

  #[test]
  fn convert_params_works_correctly() {
    let mut mapping = serde_yaml::Mapping::new();
    mapping.insert(
      serde_yaml::Value::String("test".to_string()),
      serde_yaml::Value::Null,
    );

    let mut expected = Params::new();
    expected.insert("test".to_string(), Value::Null);
    assert_eq!(convert_params(mapping).unwrap(), expected);
  }

  #[test]
  fn convert_params_invalid_key_type() {
    let mut mapping = serde_yaml::Mapping::new();
    mapping.insert(serde_yaml::Value::Null, serde_yaml::Value::Null);

    assert!(convert_params(mapping).is_err());
  }
}