import { join } from 'path';

import * as chalk from 'chalk';
import { ConfigFileSchema } from '@alwaysai/config-nodejs';
import { CLI_TERSE_ERROR } from '@alwaysai/alwayscli';
import { ALWAYSAI_CLI_EXECUTABLE_NAME } from '../../constants';
import { validateAppConfig } from '@alwaysai/app-configuration-schemas';
import { APP_JSON_FILE_NAME, APP_PY_FILE_NAME } from '../../paths';

const ENOENT = {
  message: `${APP_JSON_FILE_NAME} not found. Did you run "${ALWAYSAI_CLI_EXECUTABLE_NAME} app configure"?`,
  code: CLI_TERSE_ERROR
};

export function AppJsonFile(dir = process.cwd()) {
  const configFile = ConfigFileSchema({
    path: join(dir, APP_JSON_FILE_NAME),
    validateFunction: validateAppConfig,
    ENOENT,
    initialValue: {
      models: {},
      scripts: {
        start: `python ${APP_PY_FILE_NAME}`
      }
    }
  });

  return {
    ...configFile,
    name: APP_JSON_FILE_NAME,
    addModel(id: string, version: number) {
      return configFile.update((config) => {
        config.models = config.models || {};
        config.models[id] = version;
      });
    },
    removeModel(id: string) {
      return configFile.update((config) => {
        if (config.models) {
          delete config.models[id];
        }
      });
    },
    describeModels() {
      const config = configFile.readIfExists();
      const MODELS_COLON = 'Models:';
      if (!config) {
        return `${MODELS_COLON} "${APP_JSON_FILE_NAME}" not found`;
      }
      let description = `${MODELS_COLON} ${chalk.bold('None')}`;
      if (config.models) {
        const entries = Object.entries(config.models);
        if (entries.length > 0) {
          description = `${MODELS_COLON}\n${entries
            .map(([modelId, modelVersion]) => `  ${modelId}@${modelVersion}`)
            .join('\n')}`;
        }
      }
      return description;
    },

    describeScripts() {
      const config = configFile.readIfExists();
      const SCRIPTS_COLON = 'Scripts:';
      if (!config) {
        return `${SCRIPTS_COLON} "${APP_JSON_FILE_NAME}" not found`;
      }
      let description = `${SCRIPTS_COLON} ${chalk.bold('None')}`;
      if (config.scripts) {
        const entries = Object.entries(config.scripts);
        if (entries.length > 0) {
          description = `${SCRIPTS_COLON}\n${entries
            .map(
              ([scriptName, scriptValue]) =>
                `  ${scriptName} => "${scriptValue}"`
            )
            .join('\n')}`;
        }
      }
      return description;
    }
  };
}