package report

import (
	"fmt"

	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
)

type Registry struct {
	definitions map[ID]Definition
}

func DefaultRegistry() Registry {
	definitions := []Definition{
		dailyDefinition(),
		todayDefinition(),
		tomorrowDefinition(),
		hourlyDefinition(),
		threeDayDefinition(),
		weekendDefinition(),
		stormDefinition(),
	}
	registry := Registry{definitions: map[ID]Definition{}}
	for _, definition := range definitions {
		registry.definitions[definition.ID] = definition
	}
	return registry
}

func (r Registry) WithModuleOverrides(overrides map[ID][]module.ConfigItem) (Registry, error) {
	next := Registry{definitions: map[ID]Definition{}}
	for id, definition := range r.definitions {
		next.definitions[id] = cloneDefinition(definition)
	}
	for id, items := range overrides {
		definition, ok := next.definitions[id]
		if !ok {
			return Registry{}, fmt.Errorf("unknown report %q", id)
		}
		definition.Modules = cloneModuleItems(items)
		next.definitions[id] = definition
	}
	return next, nil
}

func cloneDefinition(definition Definition) Definition {
	definition.Modules = cloneModuleItems(definition.Modules)
	definition.DistributorPathTemplates = append([]string(nil), definition.DistributorPathTemplates...)
	return definition
}

func moduleItems(ids ...module.ID) []module.ConfigItem {
	items := make([]module.ConfigItem, 0, len(ids))
	for _, id := range ids {
		items = append(items, module.ConfigItem{ID: id})
	}
	return items
}

func cloneModuleItems(items []module.ConfigItem) []module.ConfigItem {
	cloned := make([]module.ConfigItem, len(items))
	copy(cloned, items)
	return cloned
}

func (r Registry) Lookup(id ID) (Definition, error) {
	definition, ok := r.definitions[id]
	if !ok {
		return Definition{}, fmt.Errorf("unknown report %q", id)
	}
	return definition, nil
}

func (r Registry) MustLookup(id ID) Definition {
	definition, err := r.Lookup(id)
	if err != nil {
		panic(err)
	}
	return definition
}

func (r Registry) All() []Definition {
	ids := []ID{Daily, Today, Tomorrow, Hourly, ThreeDay, Weekend, Storm}
	out := make([]Definition, 0, len(ids))
	for _, id := range ids {
		if definition, ok := r.definitions[id]; ok {
			out = append(out, definition)
		}
	}
	return out
}