use heck::CamelCase;
use proc_macro2::TokenStream;
use quote::{format_ident, quote};
use sea_query::DynIden;

use crate::WithSerde;

#[derive(Clone, Debug)]
pub struct ActiveEnum {
    pub(crate) enum_name: DynIden,
    pub(crate) values: Vec<DynIden>,
}

impl ActiveEnum {
    pub fn impl_active_enum(&self, with_serde: &WithSerde, with_copy_enums: bool) -> TokenStream {
        let enum_name = &self.enum_name.to_string();
        let enum_iden = format_ident!("{}", enum_name.to_camel_case());
        let values: Vec<String> = self.values.iter().map(|v| v.to_string()).collect();
        let variants = values.iter().map(|v| v.trim()).map(|v| {
            if v.chars().next().map(char::is_numeric).unwrap_or(false) {
                format_ident!("_{}", v)
            } else {
                format_ident!("{}", v.to_camel_case())
            }
        });

        let extra_derive = with_serde.extra_derive();
        let copy_derive = if with_copy_enums {
            quote! { , Copy }
        } else {
            quote! {}
        };

        quote! {
            #[derive(Debug, Clone, PartialEq, Eq, EnumIter, DeriveActiveEnum #copy_derive #extra_derive)]
            #[sea_orm(rs_type = "String", db_type = "Enum", enum_name = #enum_name)]
            pub enum #enum_iden {
                #(
                    #[sea_orm(string_value = #values)]
                    #variants,
                )*
            }
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use pretty_assertions::assert_eq;
    use sea_query::{Alias, IntoIden};

    #[test]
    fn test_enum_variant_starts_with_number() {
        assert_eq!(
            ActiveEnum {
                enum_name: Alias::new("media_type").into_iden(),
                values: vec![
                    "UNKNOWN",
                    "BITMAP",
                    "DRAWING",
                    "AUDIO",
                    "VIDEO",
                    "MULTIMEDIA",
                    "OFFICE",
                    "TEXT",
                    "EXECUTABLE",
                    "ARCHIVE",
                    "3D",
                ]
                .into_iter()
                .map(|variant| Alias::new(variant).into_iden())
                .collect(),
            }
            .impl_active_enum(&WithSerde::None, true)
            .to_string(),
            quote!(
                #[derive(Debug, Clone, PartialEq, Eq, EnumIter, DeriveActiveEnum, Copy)]
                #[sea_orm(rs_type = "String", db_type = "Enum", enum_name = "media_type")]
                pub enum MediaType {
                    #[sea_orm(string_value = "UNKNOWN")]
                    Unknown,
                    #[sea_orm(string_value = "BITMAP")]
                    Bitmap,
                    #[sea_orm(string_value = "DRAWING")]
                    Drawing,
                    #[sea_orm(string_value = "AUDIO")]
                    Audio,
                    #[sea_orm(string_value = "VIDEO")]
                    Video,
                    #[sea_orm(string_value = "MULTIMEDIA")]
                    Multimedia,
                    #[sea_orm(string_value = "OFFICE")]
                    Office,
                    #[sea_orm(string_value = "TEXT")]
                    Text,
                    #[sea_orm(string_value = "EXECUTABLE")]
                    Executable,
                    #[sea_orm(string_value = "ARCHIVE")]
                    Archive,
                    #[sea_orm(string_value = "3D")]
                    _3D,
                }
            )
            .to_string()
        )
    }
}