use crate::database::schema::Schema;
use std::sync::Arc;

impl Schema {
  #[allow(unused_variables)]
  pub(crate) fn validate_identifier(
    id: &str,
    field_name: &str,
    root_id: &str,
    path: &str,
    errors: &mut Vec<crate::drop::Error>,
  ) {
    #[cfg(not(test))]
    for c in id.chars() {
      if !c.is_ascii_lowercase() && !c.is_ascii_digit() && c != '_' && c != '.' && c != '$' {
        errors.push(crate::drop::Error {
          code: "INVALID_IDENTIFIER".to_string(),
          message: format!(
            "Invalid character '{}' in JSON Schema '{}' property: '{}'. Identifiers must exclusively contain [a-z0-9_.$]",
             c, field_name, id
          ),
          details: crate::drop::ErrorDetails {
             path: Some(path.to_string()),
             schema: Some(root_id.to_string()),
             ..Default::default()
          },
        });
        return;
      }
    }
  }

  pub fn collect_schemas(
    schema_arc: &Arc<Schema>,
    root_id: &str,
    path: String,
    to_insert: &mut Vec<(String, Arc<Schema>)>,
    errors: &mut Vec<crate::drop::Error>,
  ) {
    if let Some(crate::database::object::SchemaTypeOrArray::Single(t)) = &schema_arc.obj.type_ {
      if t == "array" {
        if let Some(items) = &schema_arc.obj.items {
          if let Some(crate::database::object::SchemaTypeOrArray::Single(it)) = &items.obj.type_ {
            if !crate::database::object::is_primitive_type(it) {
              if items.obj.properties.is_some() || items.obj.cases.is_some() {
                to_insert.push((path.clone(), Arc::clone(schema_arc)));
              }
            }
          }
        }
      } else if !crate::database::object::is_primitive_type(t) {
        Self::validate_identifier(t, "type", root_id, &path, errors);

        // Is this an explicit inline ad-hoc composition?
        if schema_arc.obj.properties.is_some() || schema_arc.obj.cases.is_some() {
          to_insert.push((path.clone(), Arc::clone(schema_arc)));
        }
      }
    }

    if let Some(family) = &schema_arc.obj.family {
      Self::validate_identifier(family, "family", root_id, &path, errors);
    }

    Self::collect_child_schemas(schema_arc, root_id, path, to_insert, errors);
  }

  pub fn collect_child_schemas(
    schema_arc: &Arc<Schema>,
    root_id: &str,
    path: String,
    to_insert: &mut Vec<(String, Arc<Schema>)>,
    errors: &mut Vec<crate::drop::Error>,
  ) {
    if let Some(props) = &schema_arc.obj.properties {
      for (k, v) in props.iter() {
        let next_path = format!("{}/{}", path, k);
        Self::collect_schemas(v, root_id, next_path, to_insert, errors);
      }
    }

    if let Some(pattern_props) = &schema_arc.obj.pattern_properties {
      for (k, v) in pattern_props.iter() {
        let next_path = format!("{}/{}", path, k);
        Self::collect_schemas(v, root_id, next_path, to_insert, errors);
      }
    }

    let mut map_arr = |arr: &Vec<Arc<Schema>>, sub: &str| {
      for (i, v) in arr.iter().enumerate() {
        Self::collect_schemas(
          v,
          root_id,
          format!("{}/{}/{}", path, sub, i),
          to_insert,
          errors,
        );
      }
    };

    if let Some(arr) = &schema_arc.obj.prefix_items {
      map_arr(arr, "prefixItems");
    }

    if let Some(arr) = &schema_arc.obj.one_of {
      map_arr(arr, "oneOf");
    }

    let mut map_opt = |opt: &Option<Arc<Schema>>, pass_path: bool, sub: &str| {
      if let Some(v) = opt {
        if pass_path {
          // Arrays explicitly push their wrapper natively.
          // 'items' becomes a transparent conduit, bypassing self-promotion and skipping the '/items' suffix.
          Self::collect_child_schemas(v, root_id, path.clone(), to_insert, errors);
        } else {
          Self::collect_child_schemas(v, root_id, format!("{}/{}", path, sub), to_insert, errors);
        }
      }
    };

    map_opt(
      &schema_arc.obj.additional_properties,
      false,
      "additionalProperties",
    );
    map_opt(&schema_arc.obj.items, true, "items");
    map_opt(&schema_arc.obj.not, false, "not");
    map_opt(&schema_arc.obj.contains, false, "contains");
    map_opt(&schema_arc.obj.property_names, false, "propertyNames");

    if let Some(cases) = &schema_arc.obj.cases {
      for (i, c) in cases.iter().enumerate() {
        if let Some(when) = &c.when {
          Self::collect_schemas(
            when,
            root_id,
            format!("{}/cases/{}/when", path, i),
            to_insert,
            errors,
          );
        }
        if let Some(then) = &c.then {
          Self::collect_schemas(
            then,
            root_id,
            format!("{}/cases/{}/then", path, i),
            to_insert,
            errors,
          );
        }
        if let Some(else_) = &c.else_ {
          Self::collect_schemas(
            else_,
            root_id,
            format!("{}/cases/{}/else", path, i),
            to_insert,
            errors,
          );
        }
      }
    }
  }
}