import type { Arguments } from 'yargs-parser';
import { TargetConfiguration, WorkspaceJsonConfiguration } from './workspace';
import { logger } from './logger';

type PropertyDescription = {
  type?: string;
  required?: string[];
  enum?: string[];
  properties?: any;
  oneOf?: PropertyDescription[];
  anyOf?: PropertyDescription[];
  allOf?: PropertyDescription[];
  items?: any;
  alias?: string;
  aliases?: string[];
  description?: string;
  format?: string;
  visible?: boolean;
  default?:
    | string
    | number
    | boolean
    | string[]
    | { [key: string]: string | number | boolean | string[] };
  $ref?: string;
  $default?: { $source: 'argv'; index: number } | { $source: 'projectName' };
  additionalProperties?: boolean;
  'x-prompt'?:
    | string
    | { message: string; type: string; items: any[]; multiselect?: boolean };
  'x-deprecated'?: boolean | string;

  // Numbers Only
  multipleOf?: number;
  minimum?: number;
  exclusiveMinimum?: number;
  maximum?: number;
  exclusiveMaximum?: number;

  // Strings Only
  pattern?: string;
  minLength?: number;
  maxLength?: number;
};

type Properties = {
  [p: string]: PropertyDescription;
};
export type Schema = {
  properties: Properties;
  required?: string[];
  description?: string;
  definitions?: Properties;
  additionalProperties?: boolean;
};

export type Unmatched = {
  name: string;
  possible: string[];
};

export type Options = {
  '--'?: Unmatched[];
  [k: string]: string | number | boolean | string[] | Unmatched[];
};

export async function handleErrors(isVerbose: boolean, fn: Function) {
  try {
    return await fn();
  } catch (err) {
    if (err.constructor.name === 'UnsuccessfulWorkflowExecution') {
      logger.error('The generator workflow failed. See above.');
    } else if (err.message) {
      logger.error(err.message);
    } else {
      logger.error(err);
    }
    if (isVerbose && err.stack) {
      logger.info(err.stack);
    }
    return 1;
  }
}

function camelCase(input: string): string {
  if (input.indexOf('-') > 1) {
    return input
      .toLowerCase()
      .replace(/-(.)/g, (match, group1) => group1.toUpperCase());
  } else {
    return input;
  }
}

export function convertToCamelCase(parsed: Arguments): Options {
  return Object.keys(parsed).reduce(
    (m, c) => ({ ...m, [camelCase(c)]: parsed[c] }),
    {}
  );
}

/**
 * Coerces (and replaces) options identified as 'boolean' or 'number' in the Schema
 *
 * @param opts The options to check
 * @param schema The schema definition with types to check against
 *
 */
export function coerceTypesInOptions(opts: Options, schema: Schema): Options {
  Object.keys(opts).forEach((k) => {
    const prop = findSchemaForProperty(k, schema);

    opts[k] = coerceType(prop?.description, opts[k]);
  });
  return opts;
}

function coerceType(prop: PropertyDescription | undefined, value: any) {
  if (!prop) return value;
  if (typeof value !== 'string' && value !== undefined) return value;

  if (prop.oneOf) {
    for (let i = 0; i < prop.oneOf.length; ++i) {
      const coerced = coerceType(prop.oneOf[i], value);
      if (coerced !== value) {
        return coerced;
      }
    }
    return value;
  } else if (
    normalizedPrimitiveType(prop.type) == 'boolean' &&
    isConvertibleToBoolean(value)
  ) {
    return value === true || value == 'true';
  } else if (
    normalizedPrimitiveType(prop.type) == 'number' &&
    isConvertibleToNumber(value)
  ) {
    return Number(value);
  } else if (prop.type == 'array') {
    return value.split(',').map((v) => coerceType(prop.items, v));
  } else {
    return value;
  }
}

/**
 * Converts any options passed in with short aliases to their full names if found
 * Unmatched options are added to opts['--']
 *
 * @param opts The options passed in by the user
 * @param schema The schema definition to check against
 */
export function convertAliases(
  opts: Options,
  schema: Schema,
  excludeUnmatched: boolean
): Options {
  return Object.keys(opts).reduce((acc, k) => {
    const prop = findSchemaForProperty(k, schema);
    if (prop) {
      acc[prop.name] = opts[k];
    } else if (excludeUnmatched) {
      if (!acc['--']) {
        acc['--'] = [];
      }
      acc['--'].push({
        name: k,
        possible: [],
      });
    } else {
      acc[k] = opts[k];
    }
    return acc;
  }, {});
}

export class SchemaError {
  constructor(public readonly message: string) {}
}

export function validateOptsAgainstSchema(
  opts: { [k: string]: any },
  schema: Schema
) {
  validateObject(
    opts,
    schema.properties || {},
    schema.required || [],
    schema.additionalProperties,
    schema.definitions || {}
  );
}

export function validateObject(
  opts: { [k: string]: any },
  properties: Properties,
  required: string[],
  additionalProperties: boolean | undefined,
  definitions: Properties
) {
  required.forEach((p) => {
    if (opts[p] === undefined) {
      throw new SchemaError(`Required property '${p}' is missing`);
    }
  });

  if (additionalProperties === false) {
    Object.keys(opts).find((p) => {
      if (Object.keys(properties).indexOf(p) === -1) {
        throw new SchemaError(`'${p}' is not found in schema`);
      }
    });
  }

  Object.keys(opts).forEach((p) => {
    validateProperty(p, opts[p], properties[p], definitions);
  });
}

function validateProperty(
  propName: string,
  value: any,
  schema: PropertyDescription,
  definitions: Properties
) {
  if (!schema) return;

  if (schema.$ref) {
    schema = resolveDefinition(schema.$ref, definitions);
  }

  if (schema.oneOf) {
    if (!Array.isArray(schema.oneOf))
      throw new Error(`Invalid schema file. oneOf must be an array.`);

    const passes =
      schema.oneOf.filter((r) => {
        try {
          const rule = { type: schema.type, ...r };
          validateProperty(propName, value, rule, definitions);
          return true;
        } catch (e) {
          return false;
        }
      }).length === 1;
    if (!passes) throwInvalidSchema(propName, schema);
    return;
  }

  if (schema.anyOf) {
    if (!Array.isArray(schema.anyOf))
      throw new Error(`Invalid schema file. anyOf must be an array.`);

    let passes = false;
    schema.anyOf.forEach((r) => {
      try {
        const rule = { type: schema.type, ...r };
        validateProperty(propName, value, rule, definitions);
        passes = true;
      } catch (e) {}
    });
    if (!passes) throwInvalidSchema(propName, schema);
    return;
  }

  if (schema.allOf) {
    if (!Array.isArray(schema.allOf))
      throw new Error(`Invalid schema file. anyOf must be an array.`);

    if (
      !schema.allOf.every((r) => {
        try {
          const rule = { type: schema.type, ...r };
          validateProperty(propName, value, rule, definitions);
          return true;
        } catch (e) {
          return false;
        }
      })
    ) {
      throwInvalidSchema(propName, schema);
    }
    return;
  }

  const isPrimitive = typeof value !== 'object';
  if (isPrimitive) {
    if (schema.type && typeof value !== normalizedPrimitiveType(schema.type)) {
      throw new SchemaError(
        `Property '${propName}' does not match the schema. '${value}' should be a '${schema.type}'.`
      );
    }

    if (schema.enum && !schema.enum.includes(value)) {
      throw new SchemaError(
        `Property '${propName}' does not match the schema. '${value}' should be one of ${schema.enum.join(
          ','
        )}.`
      );
    }

    if (schema.type === 'number') {
      if (
        typeof schema.multipleOf === 'number' &&
        value % schema.multipleOf !== 0
      ) {
        throw new SchemaError(
          `Property '${propName}' does not match the schema. ${value} should be a multiple of ${schema.multipleOf}.`
        );
      }
      if (typeof schema.minimum === 'number' && value < schema.minimum) {
        throw new SchemaError(
          `Property '${propName}' does not match the schema. ${value} should be at least ${schema.minimum}`
        );
      }
      if (
        typeof schema.exclusiveMinimum === 'number' &&
        value <= schema.exclusiveMinimum
      ) {
        throw new SchemaError(
          `Property '${propName}' does not match the schema. ${value} should be greater than ${schema.exclusiveMinimum}`
        );
      }
      if (typeof schema.maximum === 'number' && value > schema.maximum) {
        throw new SchemaError(
          `Property '${propName}' does not match the schema. ${value} should be at most ${schema.maximum}`
        );
      }
      if (
        typeof schema.exclusiveMaximum === 'number' &&
        value >= schema.exclusiveMaximum
      ) {
        throw new SchemaError(
          `Property '${propName}' does not match the schema. ${value} should be less than ${schema.exclusiveMaximum}`
        );
      }
    }

    if (schema.type === 'string') {
      if (schema.pattern && !new RegExp(schema.pattern).test(value)) {
        throw new SchemaError(
          `Property '${propName}' does not match the schema. '${value}' should match the pattern '${schema.pattern}'.`
        );
      }

      if (
        typeof schema.minLength === 'number' &&
        value.length < schema.minLength
      ) {
        throw new SchemaError(
          `Property '${propName}' does not match the schema. '${value}' (${value.length} character(s)) should have at least ${schema.minLength} character(s).`
        );
      }

      if (
        typeof schema.maxLength === 'number' &&
        value.length > schema.maxLength
      ) {
        throw new SchemaError(
          `Property '${propName}' does not match the schema. '${value}' (${value.length} character(s)) should have at most ${schema.maxLength} character(s).`
        );
      }
    }
  } else if (Array.isArray(value)) {
    if (schema.type !== 'array') throwInvalidSchema(propName, schema);
    value.forEach((valueInArray) =>
      validateProperty(propName, valueInArray, schema.items || {}, definitions)
    );
  } else {
    if (schema.type !== 'object') throwInvalidSchema(propName, schema);
    validateObject(
      value,
      schema.properties || {},
      schema.required || [],
      schema.additionalProperties,
      definitions
    );
  }
}

/**
 * Unfortunately, due to use supporting Angular Devkit, we have to do the following
 * conversions.
 */
function normalizedPrimitiveType(type: string) {
  if (type === 'integer') return 'number';
  return type;
}

function throwInvalidSchema(propName: string, schema: any) {
  throw new SchemaError(
    `Property '${propName}' does not match the schema.\n${JSON.stringify(
      schema,
      null,
      2
    )}'`
  );
}

export function setDefaults(opts: { [k: string]: any }, schema: Schema) {
  setDefaultsInObject(opts, schema.properties || {}, schema.definitions || {});
  return opts;
}

function setDefaultsInObject(
  opts: { [k: string]: any },
  properties: Properties,
  definitions: Properties
) {
  Object.keys(properties).forEach((p) => {
    setPropertyDefault(opts, p, properties[p], definitions);
  });
}

function setPropertyDefault(
  opts: { [k: string]: any },
  propName: string,
  schema: any,
  definitions: Properties
) {
  if (schema.$ref) {
    schema = resolveDefinition(schema.$ref, definitions);
  }

  if (schema.type !== 'object' && schema.type !== 'array') {
    if (opts[propName] === undefined && schema.default !== undefined) {
      opts[propName] = schema.default;
    }
  } else if (schema.type === 'array') {
    const items = schema.items || {};
    if (
      opts[propName] &&
      Array.isArray(opts[propName]) &&
      items.type === 'object'
    ) {
      opts[propName].forEach((valueInArray) =>
        setDefaultsInObject(valueInArray, items.properties || {}, definitions)
      );
    } else if (!opts[propName] && schema.default) {
      opts[propName] = schema.default;
    }
  } else {
    const wasUndefined = opts[propName] === undefined;
    if (wasUndefined) {
      // We need an object to set values onto
      opts[propName] = {};
    }

    setDefaultsInObject(opts[propName], schema.properties || {}, definitions);

    // If the property was initially undefined but no properties were added, we remove it again instead of having an {}
    if (wasUndefined && Object.keys(opts[propName]).length === 0) {
      delete opts[propName];
    }
  }
}

function resolveDefinition(ref: string, definitions: Properties) {
  if (!ref.startsWith('#/definitions/')) {
    throw new Error(`$ref should start with "#/definitions/"`);
  }
  const definition = ref.split('#/definitions/')[1];
  if (!definitions[definition]) {
    throw new Error(`Cannot resolve ${ref}`);
  }
  return definitions[definition];
}

export function applyVerbosity(
  options: Record<string, unknown>,
  schema: Schema,
  isVerbose: boolean
) {
  if (
    (schema.additionalProperties || 'verbose' in schema.properties) &&
    isVerbose
  ) {
    options['verbose'] = true;
  }
}

export function combineOptionsForExecutor(
  commandLineOpts: Options,
  config: string,
  target: TargetConfiguration,
  schema: Schema,
  defaultProjectName: string | null,
  relativeCwd: string | null,
  isVerbose = false
) {
  const r = convertAliases(
    coerceTypesInOptions(commandLineOpts, schema),
    schema,
    false
  );
  let combined = target.options || {};
  if (config && target.configurations && target.configurations[config]) {
    Object.assign(combined, target.configurations[config]);
  }
  combined = convertAliases(combined, schema, false);
  Object.assign(combined, r);
  convertSmartDefaultsIntoNamedParams(
    combined,
    schema,
    (commandLineOpts['_'] as string[]) || [],
    defaultProjectName,
    relativeCwd
  );
  warnDeprecations(combined, schema);
  setDefaults(combined, schema);
  validateOptsAgainstSchema(combined, schema);
  applyVerbosity(combined, schema, isVerbose);
  return combined;
}

export async function combineOptionsForGenerator(
  commandLineOpts: Options,
  collectionName: string,
  generatorName: string,
  wc: WorkspaceJsonConfiguration | null,
  schema: Schema,
  isInteractive: boolean,
  defaultProjectName: string | null,
  relativeCwd: string | null,
  isVerbose = false
) {
  const generatorDefaults = wc
    ? getGeneratorDefaults(
        defaultProjectName,
        wc,
        collectionName,
        generatorName
      )
    : {};
  let combined = convertAliases(
    coerceTypesInOptions({ ...generatorDefaults, ...commandLineOpts }, schema),
    schema,
    false
  );
  convertSmartDefaultsIntoNamedParams(
    combined,
    schema,
    (commandLineOpts['_'] as string[]) || [],
    defaultProjectName,
    relativeCwd
  );

  if (isInteractive && isTTY()) {
    combined = await promptForValues(combined, schema);
  }

  warnDeprecations(combined, schema);
  setDefaults(combined, schema);

  validateOptsAgainstSchema(combined, schema);
  applyVerbosity(combined, schema, isVerbose);
  return combined;
}

export function warnDeprecations(
  opts: { [k: string]: any },
  schema: Schema
): void {
  Object.keys(opts).forEach((option) => {
    const deprecated = schema.properties[option]?.['x-deprecated'];
    if (deprecated) {
      logger.warn(
        `Option "${option}" is deprecated${
          typeof deprecated == 'string' ? ': ' + deprecated : '.'
        }`
      );
    }
  });
}

export function convertSmartDefaultsIntoNamedParams(
  opts: { [k: string]: any },
  schema: Schema,
  argv: string[],
  defaultProjectName: string | null,
  relativeCwd: string | null
) {
  Object.entries(schema.properties).forEach(([k, v]) => {
    if (
      opts[k] === undefined &&
      v.$default !== undefined &&
      v.$default.$source === 'argv' &&
      argv[v.$default.index]
    ) {
      opts[k] = coerceType(v, argv[v.$default.index]);
    } else if (
      opts[k] === undefined &&
      v.$default !== undefined &&
      v.$default.$source === 'projectName' &&
      defaultProjectName
    ) {
      opts[k] = defaultProjectName;
    } else if (
      opts[k] === undefined &&
      v.format === 'path' &&
      v.visible === false &&
      relativeCwd
    ) {
      opts[k] = relativeCwd.replace(/\\/g, '/');
    }
  });
  delete opts['_'];
}

function getGeneratorDefaults(
  projectName: string | null,
  wc: WorkspaceJsonConfiguration,
  collectionName: string,
  generatorName: string
) {
  let defaults = {};
  if (wc.generators) {
    if (
      wc.generators[collectionName] &&
      wc.generators[collectionName][generatorName]
    ) {
      defaults = {
        ...defaults,
        ...wc.generators[collectionName][generatorName],
      };
    }
    if (wc.generators[`${collectionName}:${generatorName}`]) {
      defaults = {
        ...defaults,
        ...wc.generators[`${collectionName}:${generatorName}`],
      };
    }
  }
  if (
    projectName &&
    wc.projects[projectName] &&
    wc.projects[projectName].generators
  ) {
    const g = wc.projects[projectName].generators;
    if (g[collectionName] && g[collectionName][generatorName]) {
      defaults = { ...defaults, ...g[collectionName][generatorName] };
    }
    if (g[`${collectionName}:${generatorName}`]) {
      defaults = {
        ...defaults,
        ...g[`${collectionName}:${generatorName}`],
      };
    }
  }
  return defaults;
}

async function promptForValues(opts: Options, schema: Schema) {
  interface Prompt {
    name: string;
    type: 'input' | 'select' | 'multiselect' | 'confirm' | 'numeral';
    message: string;
    initial?: any;
    choices?: (string | { name: string; message: string })[];
  }

  const prompts: Prompt[] = [];
  Object.entries(schema.properties).forEach(([k, v]) => {
    if (v['x-prompt'] && opts[k] === undefined) {
      const question: Prompt = {
        name: k,
      } as any;

      if (v.default) {
        question.initial = v.default;
      }

      if (typeof v['x-prompt'] === 'string') {
        question.message = v['x-prompt'];
        if (v.type === 'string' && v.enum && Array.isArray(v.enum)) {
          question.type = 'select';
          question.choices = [...v.enum];
        } else {
          question.type = v.type === 'boolean' ? 'confirm' : 'input';
        }
      } else if (v['x-prompt'].type == 'number') {
        question.message = v['x-prompt'].message;
        question.type = 'numeral';
      } else if (
        v['x-prompt'].type == 'confirmation' ||
        v['x-prompt'].type == 'confirm'
      ) {
        question.message = v['x-prompt'].message;
        question.type = 'confirm';
      } else {
        question.message = v['x-prompt'].message;
        question.type = v['x-prompt'].multiselect ? 'multiselect' : 'select';
        question.choices =
          v['x-prompt'].items &&
          v['x-prompt'].items.map((item) => {
            if (typeof item == 'string') {
              return item;
            } else {
              return {
                message: item.label,
                name: item.value,
              };
            }
          });
      }
      prompts.push(question);
    }
  });

  return await (
    await import('enquirer')
  )
    .prompt(prompts)
    .then((values) => ({ ...opts, ...values }))
    .catch((e) => {
      console.error(e);
      process.exit(0);
    });
}

/**
 * Tries to find what the user meant by unmatched commands
 *
 * @param opts The options passed in by the user
 * @param schema The schema definition to check against
 *
 */
export function lookupUnmatched(opts: Options, schema: Schema): Options {
  if (opts['--']) {
    const props = Object.keys(schema.properties);

    opts['--'].forEach((unmatched) => {
      unmatched.possible = props.filter(
        (p) => levenshtein(p, unmatched.name) < 3
      );
    });
  }
  return opts;
}

function findSchemaForProperty(
  propName: string,
  schema: Schema
): { name: string; description: PropertyDescription } | null {
  if (propName in schema.properties) {
    return {
      name: propName,
      description: schema.properties[propName],
    };
  }
  const found = Object.entries(schema.properties).find(
    ([_, d]) =>
      d.alias === propName ||
      (Array.isArray(d.aliases) && d.aliases.includes(propName))
  );
  if (found) {
    const [name, description] = found;
    return { name, description };
  }
  return null;
}

function levenshtein(a: string, b: string) {
  if (a.length == 0) {
    return b.length;
  }
  if (b.length == 0) {
    return a.length;
  }
  const matrix = [];

  for (let i = 0; i <= b.length; i++) {
    matrix[i] = [i];
  }
  for (let j = 0; j <= a.length; j++) {
    matrix[0][j] = j;
  }
  for (let i = 1; i <= b.length; i++) {
    for (let j = 1; j <= a.length; j++) {
      if (b.charAt(i - 1) == a.charAt(j - 1)) {
        matrix[i][j] = matrix[i - 1][j - 1];
      } else {
        matrix[i][j] = Math.min(
          matrix[i - 1][j - 1] + 1,
          matrix[i][j - 1] + 1,
          matrix[i - 1][j] + 1
        );
      }
    }
  }
  return matrix[b.length][a.length];
}

function isTTY(): boolean {
  return !!process.stdout.isTTY && process.env['CI'] !== 'true';
}

/**
 * Verifies whether the given value can be converted to a boolean
 * @param value
 */
function isConvertibleToBoolean(value) {
  if ('boolean' === typeof value) {
    return true;
  }

  if ('string' === typeof value && /true|false/.test(value)) {
    return true;
  }

  return false;
}

/**
 * Verifies whether the given value can be converted to a number
 * @param value
 */
function isConvertibleToNumber(value) {
  // exclude booleans explicitly
  if ('boolean' === typeof value) {
    return false;
  }

  return !isNaN(+value);
}