import * as Chunk from "../Chunk.js"
import type * as Config from "../Config.js"
import * as ConfigError from "../ConfigError.js"
import * as Duration from "../Duration.js"
import * as Either from "../Either.js"
import type { LazyArg } from "../Function.js"
import { constTrue, dual, pipe } from "../Function.js"
import type * as HashMap from "../HashMap.js"
import * as HashSet from "../HashSet.js"
import type * as LogLevel from "../LogLevel.js"
import * as Option from "../Option.js"
import { hasProperty, type Predicate, type Refinement } from "../Predicate.js"
import type * as Redacted from "../Redacted.js"
import type * as Secret from "../Secret.js"
import * as configError from "./configError.js"
import * as core from "./core.js"
import * as defaultServices from "./defaultServices.js"
import * as effectable from "./effectable.js"
import * as OpCodes from "./opCodes/config.js"
import * as redacted_ from "./redacted.js"
import * as InternalSecret from "./secret.js"

const ConfigSymbolKey = "effect/Config"

/** @internal */
export const ConfigTypeId: Config.ConfigTypeId = Symbol.for(
  ConfigSymbolKey
) as Config.ConfigTypeId

/** @internal */
export type ConfigPrimitive =
  | Constant
  | Described
  | Fallback
  | Fail
  | Lazy
  | MapOrFail
  | Nested
  | Primitive
  | Sequence
  | Table
  | Zipped

const configVariance = {
  /* c8 ignore next */
  _A: (_: never) => _
}

const proto = {
  ...effectable.CommitPrototype,
  [ConfigTypeId]: configVariance,
  commit(this: Config.Config<unknown>) {
    return defaultServices.config(this)
  }
}

/** @internal */
export type Op<Tag extends string, Body = {}> = Config.Config<never> & Body & {
  readonly _tag: Tag
}

/** @internal */
export interface Constant extends
  Op<OpCodes.OP_CONSTANT, {
    readonly value: unknown
    parse(text: string): Either.Either<unknown, ConfigError.ConfigError>
  }>
{}

/** @internal */
export interface Described extends
  Op<OpCodes.OP_DESCRIBED, {
    readonly config: Config.Config<unknown>
    readonly description: string
  }>
{}

/** @internal */
export interface Fallback extends
  Op<OpCodes.OP_FALLBACK, {
    readonly first: Config.Config<unknown>
    readonly second: Config.Config<unknown>
    readonly condition: Predicate<ConfigError.ConfigError>
  }>
{}

/** @internal */
export interface Fail extends
  Op<OpCodes.OP_FAIL, {
    readonly message: string
    parse(text: string): Either.Either<unknown, ConfigError.ConfigError>
  }>
{}

/** @internal */
export interface Lazy extends
  Op<OpCodes.OP_LAZY, {
    config(): Config.Config<unknown>
  }>
{}

/** @internal */
export interface MapOrFail extends
  Op<OpCodes.OP_MAP_OR_FAIL, {
    readonly original: Config.Config<unknown>
    mapOrFail(value: unknown): Either.Either<unknown, ConfigError.ConfigError>
  }>
{}

/** @internal */
export interface Nested extends
  Op<OpCodes.OP_NESTED, {
    readonly name: string
    readonly config: Config.Config<unknown>
  }>
{}

/** @internal */
export interface Primitive extends
  Op<OpCodes.OP_PRIMITIVE, {
    readonly description: string
    parse(text: string): Either.Either<unknown, ConfigError.ConfigError>
  }>
{}

/** @internal */
export interface Sequence extends
  Op<OpCodes.OP_SEQUENCE, {
    readonly config: Config.Config<unknown>
  }>
{}

/** @internal */
export interface Table extends
  Op<OpCodes.OP_HASHMAP, {
    readonly op: OpCodes.OP_HASHMAP
    readonly valueConfig: Config.Config<unknown>
  }>
{}

/** @internal */
export interface Zipped extends
  Op<OpCodes.OP_ZIP_WITH, {
    readonly op: OpCodes.OP_ZIP_WITH
    readonly left: Config.Config<unknown>
    readonly right: Config.Config<unknown>
    zip(a: unknown, b: unknown): unknown
  }>
{}

/** @internal */
export const boolean = (name?: string): Config.Config<boolean> => {
  const config = primitive(
    "a boolean property",
    (text) => {
      switch (text) {
        case "true":
        case "yes":
        case "on":
        case "1": {
          return Either.right(true)
        }
        case "false":
        case "no":
        case "off":
        case "0": {
          return Either.right(false)
        }
        default: {
          const error = configError.InvalidData(
            [],
            `Expected a boolean value but received ${text}`
          )
          return Either.left(error)
        }
      }
    }
  )
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const url = (name?: string): Config.Config<URL> => {
  const config = primitive(
    "an URL property",
    (text) =>
      Either.try({
        try: () => new URL(text),
        catch: (_) => configError.InvalidData([], `Expected an URL value but received ${text}`)
      })
  )
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const array = <A>(config: Config.Config<A>, name?: string): Config.Config<Array<A>> => {
  return pipe(chunk(config, name), map(Chunk.toArray))
}

/** @internal */
export const chunk = <A>(config: Config.Config<A>, name?: string): Config.Config<Chunk.Chunk<A>> => {
  return map(name === undefined ? repeat(config) : nested(repeat(config), name), Chunk.unsafeFromArray)
}

/** @internal */
export const date = (name?: string): Config.Config<Date> => {
  const config = primitive(
    "a date property",
    (text) => {
      const result = Date.parse(text)
      if (Number.isNaN(result)) {
        return Either.left(
          configError.InvalidData(
            [],
            `Expected a Date value but received ${text}`
          )
        )
      }
      return Either.right(new Date(result))
    }
  )
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const fail = (message: string): Config.Config<never> => {
  const fail = Object.create(proto)
  fail._tag = OpCodes.OP_FAIL
  fail.message = message
  fail.parse = () => Either.left(configError.Unsupported([], message))
  return fail
}

/** @internal */
export const number = (name?: string): Config.Config<number> => {
  const config = primitive(
    "a number property",
    (text) => {
      const result = Number(text)
      if (Number.isNaN(result)) {
        return Either.left(
          configError.InvalidData(
            [],
            `Expected a number value but received ${text}`
          )
        )
      }
      return Either.right(result)
    }
  )
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const integer = (name?: string): Config.Config<number> => {
  const config = primitive(
    "an integer property",
    (text) => {
      const result = Number(text)
      if (!Number.isInteger(result)) {
        return Either.left(
          configError.InvalidData(
            [],
            `Expected an integer value but received ${text}`
          )
        )
      }
      return Either.right(result)
    }
  )
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const literal = <Literals extends ReadonlyArray<Config.LiteralValue>>(...literals: Literals) =>
(
  name?: string
): Config.Config<Literals[number]> => {
  const valuesString = literals.map(String).join(", ")
  const config = primitive(`one of (${valuesString})`, (text) => {
    const found = literals.find((value) => String(value) === text)
    if (found === undefined) {
      return Either.left(
        configError.InvalidData(
          [],
          `Expected one of (${valuesString}) but received ${text}`
        )
      )
    }
    return Either.right(found)
  })
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const logLevel = (name?: string): Config.Config<LogLevel.LogLevel> => {
  const config = mapOrFail(string(), (value) => {
    const label = value.toUpperCase()
    const level = core.allLogLevels.find((level) => level.label === label)
    return level === undefined
      ? Either.left(configError.InvalidData([], `Expected a log level but received ${value}`))
      : Either.right(level)
  })
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const duration = (name?: string): Config.Config<Duration.Duration> => {
  const config = mapOrFail(string(), (value) => {
    const duration = Duration.decodeUnknown(value)
    return Either.fromOption(duration, () => configError.InvalidData([], `Expected a duration but received ${value}`))
  })
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const map = dual<
  <A, B>(f: (a: A) => B) => (self: Config.Config<A>) => Config.Config<B>,
  <A, B>(self: Config.Config<A>, f: (a: A) => B) => Config.Config<B>
>(2, (self, f) => mapOrFail(self, (a) => Either.right(f(a))))

/** @internal */
export const mapAttempt = dual<
  <A, B>(f: (a: A) => B) => (self: Config.Config<A>) => Config.Config<B>,
  <A, B>(self: Config.Config<A>, f: (a: A) => B) => Config.Config<B>
>(2, (self, f) =>
  mapOrFail(self, (a) => {
    try {
      return Either.right(f(a))
    } catch (error) {
      return Either.left(
        configError.InvalidData(
          [],
          error instanceof Error ? error.message : `${error}`
        )
      )
    }
  }))

/** @internal */
export const mapOrFail = dual<
  <A, B>(f: (a: A) => Either.Either<B, ConfigError.ConfigError>) => (self: Config.Config<A>) => Config.Config<B>,
  <A, B>(self: Config.Config<A>, f: (a: A) => Either.Either<B, ConfigError.ConfigError>) => Config.Config<B>
>(2, (self, f) => {
  const mapOrFail = Object.create(proto)
  mapOrFail._tag = OpCodes.OP_MAP_OR_FAIL
  mapOrFail.original = self
  mapOrFail.mapOrFail = f
  return mapOrFail
})

/** @internal */
export const nested = dual<
  (name: string) => <A>(self: Config.Config<A>) => Config.Config<A>,
  <A>(self: Config.Config<A>, name: string) => Config.Config<A>
>(2, (self, name) => {
  const nested = Object.create(proto)
  nested._tag = OpCodes.OP_NESTED
  nested.name = name
  nested.config = self
  return nested
})

/** @internal */
export const orElse = dual<
  <A2>(that: LazyArg<Config.Config<A2>>) => <A>(self: Config.Config<A>) => Config.Config<A | A2>,
  <A, A2>(self: Config.Config<A>, that: LazyArg<Config.Config<A2>>) => Config.Config<A | A2>
>(2, (self, that) => {
  const fallback = Object.create(proto)
  fallback._tag = OpCodes.OP_FALLBACK
  fallback.first = self
  fallback.second = suspend(that)
  fallback.condition = constTrue
  return fallback
})

/** @internal */
export const orElseIf = dual<
  <A2>(
    options: {
      readonly if: Predicate<ConfigError.ConfigError>
      readonly orElse: LazyArg<Config.Config<A2>>
    }
  ) => <A>(self: Config.Config<A>) => Config.Config<A>,
  <A, A2>(
    self: Config.Config<A>,
    options: {
      readonly if: Predicate<ConfigError.ConfigError>
      readonly orElse: LazyArg<Config.Config<A2>>
    }
  ) => Config.Config<A>
>(2, (self, options) => {
  const fallback = Object.create(proto)
  fallback._tag = OpCodes.OP_FALLBACK
  fallback.first = self
  fallback.second = suspend(options.orElse)
  fallback.condition = options.if
  return fallback
})

/** @internal */
export const option = <A>(self: Config.Config<A>): Config.Config<Option.Option<A>> => {
  return pipe(
    self,
    map(Option.some),
    orElseIf({ orElse: () => succeed(Option.none()), if: ConfigError.isMissingDataOnly })
  )
}

/** @internal */
export const primitive = <A>(
  description: string,
  parse: (text: string) => Either.Either<A, ConfigError.ConfigError>
): Config.Config<A> => {
  const primitive = Object.create(proto)
  primitive._tag = OpCodes.OP_PRIMITIVE
  primitive.description = description
  primitive.parse = parse
  return primitive
}

/** @internal */
export const repeat = <A>(self: Config.Config<A>): Config.Config<Array<A>> => {
  const repeat = Object.create(proto)
  repeat._tag = OpCodes.OP_SEQUENCE
  repeat.config = self
  return repeat
}

/** @internal */
export const secret = (name?: string): Config.Config<Secret.Secret> => {
  const config = primitive(
    "a secret property",
    (text) => Either.right(InternalSecret.fromString(text))
  )
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const redacted = <A>(
  nameOrConfig?: string | Config.Config<A>
): Config.Config<Redacted.Redacted<A | string>> => {
  const config: Config.Config<A | string> = isConfig(nameOrConfig) ? nameOrConfig : string(nameOrConfig)
  return map(config, redacted_.make)
}

/** @internal */
export const hashSet = <A>(config: Config.Config<A>, name?: string): Config.Config<HashSet.HashSet<A>> => {
  const newConfig = map(chunk(config), HashSet.fromIterable)
  return name === undefined ? newConfig : nested(newConfig, name)
}

/** @internal */
export const string = (name?: string): Config.Config<string> => {
  const config = primitive(
    "a text property",
    Either.right
  )
  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const nonEmptyString = (name?: string): Config.Config<string> => {
  const config = primitive(
    "a non-empty text property",
    Either.liftPredicate((text) => text.length > 0, () => configError.MissingData([], "Expected a non-empty string"))
  )

  return name === undefined ? config : nested(config, name)
}

/** @internal */
export const all = <const Arg extends Iterable<Config.Config<any>> | Record<string, Config.Config<any>>>(
  arg: Arg
): Config.Config<
  [Arg] extends [ReadonlyArray<Config.Config<any>>] ? {
      -readonly [K in keyof Arg]: [Arg[K]] extends [Config.Config<infer A>] ? A : never
    }
    : [Arg] extends [Iterable<Config.Config<infer A>>] ? Array<A>
    : [Arg] extends [Record<string, Config.Config<any>>] ? {
        -readonly [K in keyof Arg]: [Arg[K]] extends [Config.Config<infer A>] ? A : never
      }
    : never
> => {
  if (Array.isArray(arg)) {
    return tuple(arg) as any
  } else if (Symbol.iterator in arg) {
    return tuple([...(arg as Iterable<Config.Config<any>>)]) as any
  }
  return struct(arg) as any
}

const struct = <NER extends Record<string, Config.Config<any>>>(r: NER): Config.Config<
  {
    [K in keyof NER]: [NER[K]] extends [{ [ConfigTypeId]: { _A: (_: never) => infer A } }] ? A : never
  }
> => {
  const entries = Object.entries(r)
  let result = pipe(entries[0][1], map((value) => ({ [entries[0][0]]: value })))
  if (entries.length === 1) {
    return result as any
  }
  const rest = entries.slice(1)
  for (const [key, config] of rest) {
    result = pipe(
      result,
      zipWith(config, (record, value) => ({ ...record, [key]: value }))
    )
  }
  return result as any
}

/** @internal */
export const succeed = <A>(value: A): Config.Config<A> => {
  const constant = Object.create(proto)
  constant._tag = OpCodes.OP_CONSTANT
  constant.value = value
  constant.parse = () => Either.right(value)
  return constant
}

/** @internal */
export const suspend = <A>(config: LazyArg<Config.Config<A>>): Config.Config<A> => {
  const lazy = Object.create(proto)
  lazy._tag = OpCodes.OP_LAZY
  lazy.config = config
  return lazy
}

/** @internal */
export const sync = <A>(value: LazyArg<A>): Config.Config<A> => {
  return suspend(() => succeed(value()))
}

/** @internal */
export const hashMap = <A>(config: Config.Config<A>, name?: string): Config.Config<HashMap.HashMap<string, A>> => {
  const table = Object.create(proto)
  table._tag = OpCodes.OP_HASHMAP
  table.valueConfig = config
  return name === undefined ? table : nested(table, name)
}

/** @internal */
export const isConfig = (u: unknown): u is Config.Config<unknown> => hasProperty(u, ConfigTypeId)

/** @internal */
const tuple = <T extends ArrayLike<Config.Config<any>>>(tuple: T): Config.Config<
  {
    [K in keyof T]: [T[K]] extends [Config.Config<infer A>] ? A : never
  }
> => {
  if (tuple.length === 0) {
    return succeed([]) as any
  }
  if (tuple.length === 1) {
    return map(tuple[0], (x) => [x]) as any
  }
  let result = map(tuple[0], (x) => [x])
  for (let i = 1; i < tuple.length; i++) {
    const config = tuple[i]
    result = pipe(
      result,
      zipWith(config, (tuple, value) => [...tuple, value])
    ) as any
  }
  return result as any
}

/**
 * @internal
 */
export const unwrap = <A>(wrapped: Config.Config.Wrap<A>): Config.Config<A> => {
  if (isConfig(wrapped)) {
    return wrapped
  }
  return struct(
    Object.fromEntries(
      Object.entries(wrapped).map(([k, a]) => [k, unwrap(a as any)])
    )
  ) as any
}

/** @internal */
export const validate = dual<
  {
    <A, B extends A>(options: {
      readonly message: string
      readonly validation: Refinement<A, B>
    }): (self: Config.Config<A>) => Config.Config<B>
    <A>(options: {
      readonly message: string
      readonly validation: Predicate<A>
    }): (self: Config.Config<A>) => Config.Config<A>
  },
  {
    <A, B extends A>(self: Config.Config<A>, options: {
      readonly message: string
      readonly validation: Refinement<A, B>
    }): Config.Config<B>
    <A>(self: Config.Config<A>, options: {
      readonly message: string
      readonly validation: Predicate<A>
    }): Config.Config<A>
  }
>(2, <A>(self: Config.Config<A>, { message, validation }: {
  readonly message: string
  readonly validation: Predicate<A>
}) =>
  mapOrFail(self, (a) => {
    if (validation(a)) {
      return Either.right(a)
    }
    return Either.left(configError.InvalidData([], message))
  }))

/** @internal */
export const withDefault = dual<
  <const A2>(def: A2) => <A>(self: Config.Config<A>) => Config.Config<A | A2>,
  <A, const A2>(self: Config.Config<A>, def: A2) => Config.Config<A | A2>
>(2, (self, def) =>
  orElseIf(self, {
    orElse: () => succeed(def),
    if: ConfigError.isMissingDataOnly
  }))

/** @internal */
export const withDescription = dual<
  (description: string) => <A>(self: Config.Config<A>) => Config.Config<A>,
  <A>(self: Config.Config<A>, description: string) => Config.Config<A>
>(2, (self, description) => {
  const described = Object.create(proto)
  described._tag = OpCodes.OP_DESCRIBED
  described.config = self
  described.description = description
  return described
})

/** @internal */
export const zip = dual<
  <B>(that: Config.Config<B>) => <A>(self: Config.Config<A>) => Config.Config<[A, B]>,
  <A, B>(self: Config.Config<A>, that: Config.Config<B>) => Config.Config<[A, B]>
>(2, (self, that) => zipWith(self, that, (a, b) => [a, b]))

/** @internal */
export const zipWith = dual<
  <B, A, C>(that: Config.Config<B>, f: (a: A, b: B) => C) => (self: Config.Config<A>) => Config.Config<C>,
  <A, B, C>(self: Config.Config<A>, that: Config.Config<B>, f: (a: A, b: B) => C) => Config.Config<C>
>(3, (self, that, f) => {
  const zipWith = Object.create(proto)
  zipWith._tag = OpCodes.OP_ZIP_WITH
  zipWith.left = self
  zipWith.right = that
  zipWith.zip = f
  return zipWith
})