use crate::store::model::FieldKind;
use serde_json::Value;
use std::borrow::Cow;
use crate::store::{model, Indexes};

use lazy_static::lazy_static;

lazy_static! {
    /// This is an example for using doc comment attributes
    static ref EMPTY_VEC: Vec<String> = vec![];
}

#[derive(Serialize, Debug, Default)]
pub struct RenderedField<'a> {
    pub key: Cow<'a, str>,
    pub label: Cow<'a, str>,
    pub kind: &'static str,
    pub step: &'static str,
    pub min: String,
    pub max: String,
    pub options: Option<&'a Vec<String>>,
    pub value: Cow<'a, str>,
    pub checked: bool,
}

impl<'a> RenderedField<'a> {
    pub fn from_template_field<'i>(
        key: &'i String,
        field: &'i model::Field,
        value: Option<&'i Value>,
        index: &'i Indexes
    ) -> RenderedField<'i> {
        let mut rendered = RenderedField::default();
        rendered.key = key.as_str().into();
        rendered.label = if field.label.is_empty() {
            rendered.key.clone()
        } else {
            field.label.as_str().into()
        };

        match &field.kind {
            FieldKind::String => {
                rendered.kind = "string";

                if let Some(Value::String(s)) = value {
                    rendered.value = Cow::Borrowed(&s.as_str());
                }
            }
            FieldKind::Text => {
                rendered.kind = "text";

                if let Some(Value::String(s)) = value {
                    rendered.value = Cow::Borrowed(&s.as_str());
                }
            }
            FieldKind::Bool { default } => {
                rendered.kind = "bool";

                rendered.checked = if let Some(Value::Bool(v)) = value {
                    *v
                } else {
                    *default
                }
            }
            FieldKind::Int { min, max, default } => {
                rendered.kind = "number";

                let num = if let Some(Value::Number(n)) = value {
                    n.as_i64().expect("Error parsing number")
                } else {
                    *default
                };

                if let Some(n) = min {
                    rendered.min = n.to_string();
                }

                if let Some(n) = max {
                    rendered.max = n.to_string();
                }

                rendered.value = Cow::Owned(num.to_string());
                rendered.step = "1";
            }
            FieldKind::Float { min, max, default } => {
                rendered.kind = "number";

                let num = if let Some(Value::Number(n)) = value {
                    n.as_f64().expect("Error parsing number")
                } else {
                    *default
                };

                if let Some(n) = min {
                    rendered.min = n.to_string();
                }

                if let Some(n) = max {
                    rendered.max = n.to_string();
                }

                rendered.value = Cow::Owned(num.to_string());
                rendered.step = "any";
            }
            FieldKind::Enum { options, default } => {
                rendered.kind = "select";
                rendered.options = Some(options);
            }
            FieldKind::FreeEnum { enum_group } => {
                rendered.kind = "free_select";
                let group = enum_group.as_ref().unwrap_or(key);
                rendered.options = Some(index.free_enums.get(group).unwrap_or(&EMPTY_VEC))
            }
            FieldKind::Tags { options } => {
                rendered.kind = "select";
                rendered.options = Some(options);
            }
            FieldKind::FreeTags { tag_group } => {
                rendered.kind = "free_select";
                let group = tag_group.as_ref().unwrap_or(key);
                rendered.options = Some(index.free_tags.get(group).unwrap_or(&EMPTY_VEC))
            }
        }

        rendered
    }
}