import AbstractFactory from './factory/AbstractFactory.ts'
import Factory from './factory/Factory.ts'
import SingletonFactory from './factory/SingletonFactory.ts'
import FunctionFactory from './factory/FunctionFactory.ts'
import NamedFactory from './factory/NamedFactory.ts'
import { DependencyKey } from './type/DependencyKey.ts'
import { collect, Collection } from '../../lib/src/collection/Collection.ts'
import Instantiable, {isInstantiable} from './type/Instantiable.ts'

type MaybeFactory = AbstractFactory | undefined
type MaybeDependency = any | undefined
type ResolvedDependency = { param_index: number, key: DependencyKey, resolved: any }

interface InstanceRef {
    key: DependencyKey,
    value: any,
}

class DuplicateFactoryKeyError extends Error {
    constructor(key: DependencyKey) {
        super(`A factory definition already exists with the key for ${key}.`)
    }
}

class InvalidDependencyKeyError extends Error {
    constructor(key: DependencyKey) {
        super(`No such dependency is registered with this container: ${key}`)
    }

}

class Container {
    private factories: Collection<AbstractFactory> = new Collection<AbstractFactory>()
    private instances: Collection<InstanceRef> = new Collection<InstanceRef>()

    register(dependency: Instantiable<any>) {
        if ( this.resolve(dependency) )
            throw new DuplicateFactoryKeyError(dependency)

        const factory = new Factory(dependency)
        this.factories.push(factory)
    }

    register_producer(name: string, producer: () => any) {
        if ( this.resolve(name) )
            throw new DuplicateFactoryKeyError(name)

        const factory = new FunctionFactory(name, producer)
        this.factories.push(factory)
    }

    register_named(name: string, dependency: Instantiable<any>) {
        if ( this.resolve(name) )
            throw new DuplicateFactoryKeyError(name)

        const factory = new NamedFactory(name, dependency)
        this.factories.push(factory)
    }

    register_singleton(key: string, value: any) {
        if ( this.resolve(key) )
            throw new DuplicateFactoryKeyError(key)

        this.factories.push(new SingletonFactory(value, key))
    }

    register_factory(factory: AbstractFactory) {
        if ( !this.factories.includes(factory) )
            this.factories.push(factory)
    }

    has_instance(key: DependencyKey): boolean {
        return this.instances.where('key', '=', key).isNotEmpty()
    }

    has_key(key: DependencyKey): boolean {
        return !!this.resolve(key)
    }

    get_existing_instance(key: DependencyKey): MaybeDependency {
        const instances = this.instances.where('key', '=', key)
        if ( instances.isNotEmpty() ) return instances.first()
    }

    resolve(key: DependencyKey): MaybeFactory {
        const factory = this.factories.firstWhere(item => item.match(key))
        if ( factory ) return factory
    }

    resolve_and_create(key: DependencyKey, ...parameters: any[]): any {
        // If we've already instantiated this, just return that
        const instance = this.get_existing_instance(key)
        if ( typeof instance !== 'undefined' ) return instance.value

        // Otherwise, attempt to create it
        const factory = this.resolve(key)
        if ( !factory )
            throw new InvalidDependencyKeyError(key)

        // Produce and store a new instance
        const new_instance = this.produce_factory(factory, parameters)
        this.instances.push({
            key,
            value: new_instance,
        })

        return new_instance
    }

    protected produce_factory(factory: AbstractFactory, parameters: any[]) {
        // Create the dependencies for the factory
        const keys = factory.get_dependency_keys().filter(req => this.has_key(req.key))
        const dependencies = keys.map<ResolvedDependency>(req => {
            return {
                param_index: req.param_index,
                key: req.key,
                resolved: this.resolve_and_create(req.key),
            }
        }).sortBy('param_index')

        // Build the arguments for the factory, using dependencies in the
        // correct param_index positions, or parameters of we don't have
        // the dependency.
        const construction_args = []
        let params = collect(parameters).reverse()
        for ( let i = 0; i <= dependencies.max('param_index'); i++ ) {
            const dep = dependencies.firstWhere('param_index', '=', i)
            if ( dep ) construction_args.push(dep.resolved)
            else construction_args.push(params.pop())
        }

        // Produce a new instance
        return factory.produce(construction_args, params.reverse().all())
    }

    make(target: DependencyKey, ...parameters: any[]) {
        if ( this.has_key(target) ) {
            return this.resolve_and_create(target, ...parameters)
        }
        else if ( typeof target !== 'string' )
            return this.produce_factory(new Factory(target), parameters)
        else
            throw new TypeError(`Invalid or unknown make target: ${target}`)
    }
}

export {
    Container,
    InvalidDependencyKeyError,
    DuplicateFactoryKeyError,
    MaybeDependency,
    MaybeFactory,
    ResolvedDependency,
    InstanceRef,
}