import { encode } from "./deps.ts";
import { eventHandlers } from "../bot.ts";
import { isButton } from "../helpers/type_guards/is_button.ts";
import { Errors } from "../types/discordeno/errors.ts";
import type { ApplicationCommandOption } from "../types/interactions/commands/application_command_option.ts";
import type { ApplicationCommandOptionChoice } from "../types/interactions/commands/application_command_option_choice.ts";
import { DiscordApplicationCommandOptionTypes } from "../types/interactions/commands/application_command_option_types.ts";
import type { CreateGlobalApplicationCommand } from "../types/interactions/commands/create_global_application_command.ts";
import type { EditGlobalApplicationCommand } from "../types/interactions/commands/edit_global_application_command.ts";
import { ButtonStyles } from "../types/messages/components/button_styles.ts";
import type { MessageComponents } from "../types/messages/components/message_components.ts";
import type { DiscordImageFormat } from "../types/misc/image_format.ts";
import type { DiscordImageSize } from "../types/misc/image_size.ts";
import { CONTEXT_MENU_COMMANDS_NAME_REGEX, SLASH_COMMANDS_NAME_REGEX } from "./constants.ts";
import { validateLength } from "./validate_length.ts";
import { isSelectMenu } from "../helpers/type_guards/is_select_menu.ts";
import { ApplicationCommandTypes } from "../types/interactions/commands/application_command_types.ts";

export async function urlToBase64(url: string) {
  const buffer = await fetch(url).then((res) => res.arrayBuffer());
  const imageStr = encode(buffer);
  const type = url.substring(url.lastIndexOf(".") + 1);
  return `data:image/${type};base64,${imageStr}`;
}

/** Allows easy way to add a prop to a base object when needing to use complicated getters solution. */
// deno-lint-ignore no-explicit-any
export function createNewProp(value: any): PropertyDescriptor {
  return { configurable: true, enumerable: true, writable: true, value };
}

export function delay(ms: number): Promise<void> {
  return new Promise((res): number =>
    setTimeout((): void => {
      res();
    }, ms)
  );
}

export const formatImageURL = (url: string, size: DiscordImageSize = 128, format?: DiscordImageFormat) => {
  return `${url}.${format || (url.includes("/a_") ? "gif" : "jpg")}?size=${size}`;
};

function camelToSnakeCase(text: string) {
  return text.replace(/[A-Z]/g, ($1) => `_${$1.toLowerCase()}`);
}

function snakeToCamelCase(text: string) {
  return text.replace(/([-_][a-z])/gi, ($1) => $1.toUpperCase().replace("_", ""));
}

function isConvertableObject(obj: unknown) {
  return obj === Object(obj) && !Array.isArray(obj) && typeof obj !== "function" && !(obj instanceof Blob);
}

export function snakelize<T>(
  // deno-lint-ignore no-explicit-any
  obj: Record<string, any> | Record<string, any>[]
): T {
  if (isConvertableObject(obj)) {
    // deno-lint-ignore no-explicit-any
    const convertedObject: Record<string, any> = {};

    Object.keys(obj).forEach((key) => {
      eventHandlers.debug?.("loop", `Running forEach loop in snakelize function.`);
      convertedObject[camelToSnakeCase(key)] = snakelize(
        // deno-lint-ignore no-explicit-any
        (obj as Record<string, any>)[key]
      );
    });

    return convertedObject as T;
  } else if (Array.isArray(obj)) {
    obj = obj.map((element) => snakelize(element));
  }

  return obj as T;
}

export function camelize<T>(
  // deno-lint-ignore no-explicit-any
  obj: Record<string, any> | Record<string, any>[]
): T {
  if (isConvertableObject(obj)) {
    // deno-lint-ignore no-explicit-any
    const convertedObject: Record<string, any> = {};

    Object.keys(obj).forEach((key) => {
      eventHandlers.debug?.("loop", `Running forEach loop in camelize function.`);
      convertedObject[snakeToCamelCase(key)] = camelize(
        // deno-lint-ignore no-explicit-any
        (obj as Record<string, any>)[key]
      );
    });

    return convertedObject as T;
  } else if (Array.isArray(obj)) {
    obj = obj.map((element) => camelize(element));
  }

  return obj as T;
}

/** @private */
function validateSlashOptionChoices(
  choices: ApplicationCommandOptionChoice[],
  optionType: DiscordApplicationCommandOptionTypes
) {
  for (const choice of choices) {
    eventHandlers.debug?.("loop", `Running for of loop in validateSlashOptionChoices function.`);
    if (!validateLength(choice.name, { min: 1, max: 100 })) {
      throw new Error(Errors.INVALID_SLASH_OPTION_CHOICE_NAME);
    }

    if (
      optionType === DiscordApplicationCommandOptionTypes.String &&
      (typeof choice.value !== "string" || choice.value.length < 1 || choice.value.length > 100)
    ) {
      throw new Error(Errors.INVALID_SLASH_OPTIONS_CHOICE_VALUE_TYPE);
    }

    if (optionType === DiscordApplicationCommandOptionTypes.Integer && typeof choice.value !== "number") {
      throw new Error(Errors.INVALID_SLASH_OPTIONS_CHOICE_VALUE_TYPE);
    }
  }
}

// TODO: add checks for autocomplete options when discord provides more info about them.
/** @private */
function validateSlashOptions(options: ApplicationCommandOption[]) {
  const requiredOptions: ApplicationCommandOption[] = [];
  const optionalOptions: ApplicationCommandOption[] = [];

  for (const option of options) {
    eventHandlers.debug?.("loop", `Running for of loop in validateSlashOptions function.`);
    option.name = option.name.toLowerCase();

    if (option.choices?.length) {
      if (option.choices.length > 25) throw new Error(Errors.TOO_MANY_SLASH_OPTION_CHOICES);
      if (
        option.type !== DiscordApplicationCommandOptionTypes.String &&
        option.type !== DiscordApplicationCommandOptionTypes.Integer
      )
        throw new Error(Errors.ONLY_STRING_OR_INTEGER_OPTIONS_CAN_HAVE_CHOICES);
    }

    if (!validateLength(option.name, { min: 1, max: 32 })) throw new Error(Errors.INVALID_SLASH_OPTION_NAME);

    if (!validateLength(option.description, { min: 1, max: 100 }))
      throw new Error(Errors.INVALID_SLASH_OPTION_DESCRIPTION);

    if (option.choices) {
      validateSlashOptionChoices(option.choices, option.type);
    }

    if (option.required) {
      requiredOptions.push(option);
      continue;
    }

    optionalOptions.push(option);
  }

  return [...requiredOptions, ...optionalOptions];
}

export function validateSlashCommands(
  commands: (CreateGlobalApplicationCommand | EditGlobalApplicationCommand)[],
  create = false
) {
  return commands.map((command) => {
    eventHandlers.debug?.("loop", `Running for of loop in validateSlashCommands function.`);
    if (create) {
      if (!command.name) throw new Error(Errors.INVALID_SLASH_NAME);
      // Slash commands require description
      if (!command.description && (!command.type || command.type === ApplicationCommandTypes.ChatInput))
        throw new Error(Errors.INVALID_CONTEXT_MENU_COMMAND_DESCRIPTION);

      if (command.description && (!command.type || command.type !== ApplicationCommandTypes.ChatInput))
        throw new Error(Errors.INVALID_SLASH_DESCRIPTION);
    }

    if (command.name) {
      if (!command.type || command.type === ApplicationCommandTypes.ChatInput) {
        if (!SLASH_COMMANDS_NAME_REGEX.test(command.name)) {
          throw new Error(Errors.INVALID_SLASH_NAME);
        }

        // Only slash need to be lowercase
        command.name = command.name.toLowerCase();
      } else {
        if (!CONTEXT_MENU_COMMANDS_NAME_REGEX.test(command.name)) {
          throw new Error(Errors.INVALID_CONTEXT_MENU_COMMAND_NAME);
        }
      }
    }

    if (command.description && !validateLength(command.description, { min: 1, max: 100 })) {
      throw new Error(Errors.INVALID_SLASH_DESCRIPTION);
    }

    if (command.options?.length) {
      if (command.options.length > 25) {
        throw new Error(Errors.TOO_MANY_SLASH_OPTIONS);
      }

      command.options = validateSlashOptions(command.options);
    }

    return command;
  });
}

// Typescript is not so good as we developers so we need this little utility function to help it out
// Taken from https://fettblog.eu/typescript-hasownproperty/
/** TS save way to check if a property exists in an object */
// deno-lint-ignore ban-types
export function hasOwnProperty<T extends {}, Y extends PropertyKey = string>(
  obj: T,
  prop: Y
): obj is T & Record<Y, unknown> {
  // deno-lint-ignore no-prototype-builtins
  return obj.hasOwnProperty(prop);
}

export function validateComponents(components: MessageComponents) {
  if (!components?.length) return;

  let actionRowCounter = 0;

  for (const component of components) {
    actionRowCounter++;
    // Max of 5 ActionRows per message
    if (actionRowCounter > 5) throw new Error(Errors.TOO_MANY_ACTION_ROWS);

    // Max of 5 Buttons (or any component type) within an ActionRow
    if (component.components?.length > 5) {
      throw new Error(Errors.TOO_MANY_COMPONENTS);
    } else if (
      component.components?.length > 1 &&
      component.components.some((subcomponent) => isSelectMenu(subcomponent))
    ) {
      throw new Error(Errors.COMPONENT_SELECT_MUST_BE_ALONE);
    }

    for (const subcomponent of component.components) {
      if (subcomponent.customId && !validateLength(subcomponent.customId, { max: 100 })) {
        throw new Error(Errors.COMPONENT_CUSTOM_ID_TOO_BIG);
      }

      // 5 Link buttons can not have a customId
      if (isButton(subcomponent)) {
        if (subcomponent.style === ButtonStyles.Link && subcomponent.customId) {
          throw new Error(Errors.LINK_BUTTON_CANNOT_HAVE_CUSTOM_ID);
        }
        // Other buttons must have a customId
        if (!subcomponent.customId && subcomponent.style !== ButtonStyles.Link) {
          throw new Error(Errors.BUTTON_REQUIRES_CUSTOM_ID);
        }

        if (!validateLength(subcomponent.label, { max: 80 })) {
          throw new Error(Errors.COMPONENT_LABEL_TOO_BIG);
        }

        subcomponent.emoji = makeEmojiFromString(subcomponent.emoji);
      }

      if (isSelectMenu(subcomponent)) {
        if (subcomponent.placeholder && !validateLength(subcomponent.placeholder, { max: 100 })) {
          throw new Error(Errors.COMPONENT_PLACEHOLDER_TOO_BIG);
        }

        if (subcomponent.minValues) {
          if (subcomponent.minValues < 1) {
            throw new Error(Errors.COMPONENT_SELECT_MINVALUE_TOO_LOW);
          }

          if (subcomponent.minValues > 25) {
            throw new Error(Errors.COMPONENT_SELECT_MINVALUE_TOO_MANY);
          }

          if (!subcomponent.maxValues) subcomponent.maxValues = subcomponent.minValues;
          if (subcomponent.minValues > subcomponent.maxValues) {
            throw new Error(Errors.COMPONENT_SELECT_MIN_HIGHER_THAN_MAX);
          }
        }

        if (subcomponent.maxValues) {
          if (subcomponent.maxValues < 1) {
            throw new Error(Errors.COMPONENT_SELECT_MAXVALUE_TOO_LOW);
          }

          if (subcomponent.maxValues > 25) {
            throw new Error(Errors.COMPONENT_SELECT_MAXVALUE_TOO_MANY);
          }
        }

        if (subcomponent.options.length < 1) {
          throw new Error(Errors.COMPONENT_SELECT_OPTIONS_TOO_LOW);
        }

        if (subcomponent.options.length > 25) {
          throw new Error(Errors.COMPONENT_SELECT_OPTIONS_TOO_MANY);
        }

        let defaults = 0;

        for (const option of subcomponent.options) {
          if (option.default) {
            defaults++;
            if (defaults > (subcomponent.maxValues || 25)) {
              throw new Error(Errors.SELECT_OPTION_TOO_MANY_DEFAULTS);
            }
          }

          if (!validateLength(option.label, { max: 25 })) {
            throw new Error(Errors.SELECT_OPTION_LABEL_TOO_BIG);
          }

          if (!validateLength(option.value, { max: 100 })) {
            throw new Error(Errors.SELECT_OPTION_VALUE_TOO_BIG);
          }

          if (option.description && !validateLength(option.description, { max: 50 })) {
            throw new Error(Errors.SELECT_OPTION_VALUE_TOO_BIG);
          }

          option.emoji = makeEmojiFromString(option.emoji);
        }
      }
    }
  }
}

function makeEmojiFromString(
  emoji?:
    | string
    | {
        id?: string | undefined;
        name?: string | undefined;
        animated?: boolean | undefined;
      }
) {
  if (typeof emoji !== "string") return emoji;

  // A snowflake id was provided
  if (/^[0-9]+$/.test(emoji)) {
    emoji = {
      id: emoji,
    };
  } else {
    // A unicode emoji was provided
    emoji = {
      name: emoji,
    };
  }

  return emoji;
}