import { isString } from '@sindresorhus/is';
import validateNpmPackageName from 'validate-npm-package-name';
import { logger } from '../../../../../logger/index.ts';
import { coerceArray } from '../../../../../util/array.ts';
import type { ConstraintName } from '../../../../../util/exec/types.ts';
import { isConstraintName } from '../../../../../util/exec/types.ts';
import { regEx } from '../../../../../util/regex.ts';
import { GithubTagsDatasource } from '../../../../datasource/github-tags/index.ts';
import { NodeVersionDatasource } from '../../../../datasource/node-version/index.ts';
import { NpmDatasource } from '../../../../datasource/npm/index.ts';
import {
  api,
  isValid,
  isVersion,
  id as npmVersioningId,
} from '../../../../versioning/npm/index.ts';
import type { PackageDependency } from '../../../types.ts';

const RE_REPOSITORY_GITHUB_SSH_FORMAT = regEx(
  /(?:git@)github.com:(?<owner>[^/]+)\/(?<repo>[^/]+?)(?:\.git)?$/,
);

export function parseDepName(depType: string, key: string): string {
  if (depType !== 'resolutions') {
    return key;
  }

  // Yarn selective dependency resolutions may nest a path of parent
  // packages before the target package, e.g. `parent/child` or
  // `@scope/parent/child`, and any segment (including the last) may carry
  // a `@range` suffix used to disambiguate which version of that package
  // to match, e.g. `@cypress/request/qs@~6.14.1`.
  const parts = key.split('/');
  const segments: string[] = [];
  for (let i = 0; i < parts.length; i += 1) {
    const part = parts[i];
    if (part.startsWith('@') && i + 1 < parts.length) {
      i += 1;
      segments.push(`${part}/${parts[i]}`);
    } else {
      segments.push(part);
    }
  }

  const lastSegment = segments.at(-1);
  const [, depName] = coerceArray(
    regEx(/^(?<depName>(?:@[^/]+\/)?[^@]+)/).exec(lastSegment ?? ''),
  );
  return depName;
}

export function extractDependency(
  depType: string,
  depName: string,
  input: string,
): PackageDependency {
  const dep: PackageDependency = {};
  if (!validateNpmPackageName(depName).validForOldPackages) {
    dep.skipReason = 'invalid-name';
    return dep;
  }
  if (!isString(input)) {
    dep.skipReason = 'invalid-value';
    return dep;
  }
  dep.currentValue = input.trim();
  if (depType === 'engines' || depType === 'packageManager') {
    if (depName === 'node') {
      dep.datasource = NodeVersionDatasource.id;
    } else if (depName === 'yarn') {
      dep.datasource = NpmDatasource.id;
      dep.commitMessageTopic = 'Yarn';
      const major =
        isVersion(dep.currentValue) && api.getMajor(dep.currentValue);
      if (major && major > 1) {
        dep.packageName = '@yarnpkg/cli';
      }
    } else if (depName === 'npm') {
      dep.datasource = NpmDatasource.id;
      dep.commitMessageTopic = 'npm';
    } else if (depName === 'pnpm') {
      dep.datasource = NpmDatasource.id;
      dep.commitMessageTopic = 'pnpm';
    } else if (depName === 'vscode') {
      dep.datasource = GithubTagsDatasource.id;
      dep.packageName = 'microsoft/vscode';
      dep.versioning = npmVersioningId;
    } else if (depName === 'bun') {
      dep.datasource = NpmDatasource.id;
      dep.commitMessageTopic = 'Bun';
    } else {
      dep.skipReason = 'unknown-engines';
    }
    if (!isValid(dep.currentValue)) {
      dep.skipReason = 'unspecified-version';
    }
    return dep;
  }

  // support for volta
  if (depType === 'volta') {
    if (depName === 'node') {
      dep.datasource = NodeVersionDatasource.id;
    } else if (depName === 'yarn') {
      dep.datasource = NpmDatasource.id;
      dep.commitMessageTopic = 'Yarn';
      const major =
        isVersion(dep.currentValue) && api.getMajor(dep.currentValue);
      if (major && major > 1) {
        dep.packageName = '@yarnpkg/cli';
      }
    } else if (depName === 'npm') {
      dep.datasource = NpmDatasource.id;
    } else if (depName === 'pnpm') {
      dep.datasource = NpmDatasource.id;
      dep.commitMessageTopic = 'pnpm';
    } else {
      dep.skipReason = 'unknown-volta';
    }
    if (!isValid(dep.currentValue)) {
      dep.skipReason = 'unspecified-version';
    }
    return dep;
  }

  if (dep.currentValue.startsWith('npm:')) {
    dep.npmPackageAlias = true;
    const valSplit = dep.currentValue.replace('npm:', '').split('@');
    if (valSplit.length === 1) {
      dep.packageName = depName;
      dep.currentValue = valSplit[0];
    } else if (valSplit.length === 2) {
      dep.packageName = valSplit[0];
      dep.currentValue = valSplit[1];
    } else if (valSplit.length === 3) {
      dep.packageName = `${valSplit[0]}@${valSplit[1]}`;
      dep.currentValue = valSplit[2];
    } else {
      logger.debug(
        `Invalid npm package alias for dependency: "${depName}":"${dep.currentValue}"`,
      );
    }
  }
  if (dep.currentValue.startsWith('file:')) {
    dep.skipReason = 'file';
    return dep;
  }

  if (isValid(dep.currentValue)) {
    dep.datasource = NpmDatasource.id;
    if (dep.currentValue === '') {
      dep.skipReason = 'empty';
    }
    return dep;
  }
  const hashSplit = dep.currentValue.split('#');
  if (hashSplit.length !== 2) {
    dep.skipReason = 'unspecified-version';
    return dep;
  }
  const [depNamePart, depRefPart] = hashSplit;

  let githubOwnerRepo: string;
  let githubOwner: string;
  let githubRepo: string;
  const matchUrlSshFormat = RE_REPOSITORY_GITHUB_SSH_FORMAT.exec(depNamePart);
  if (matchUrlSshFormat === null) {
    githubOwnerRepo = depNamePart
      .replace(regEx(/^github:/), '')
      .replace(regEx(/^git\+/), '')
      .replace(regEx(/^https:\/\/github\.com\//), '')
      .replace(regEx(/\.git$/), '');
    const githubRepoSplit = githubOwnerRepo.split('/');
    if (githubRepoSplit.length !== 2) {
      dep.skipReason = 'unspecified-version';
      return dep;
    }
    [githubOwner, githubRepo] = githubRepoSplit;
  } else {
    githubOwner = matchUrlSshFormat.groups!.owner;
    githubRepo = matchUrlSshFormat.groups!.repo;
    githubOwnerRepo = `${githubOwner}/${githubRepo}`;
  }
  // combined with the length check below, this is equivalent to
  // /^[a-z\d](?:[a-z\d]|-(?=[a-z\d])){0,38}$/i without the lookahead
  const githubOwnerRegex = regEx(/^[a-z\d](?:-?[a-z\d]){0,38}$/i);
  const githubRepoRegex = regEx(/^[a-zA-Z0-9._-]{1,100}$/);
  if (
    githubOwner.length > 39 ||
    !githubOwnerRegex.test(githubOwner) ||
    !githubRepoRegex.test(githubRepo)
  ) {
    dep.skipReason = 'unspecified-version';
    return dep;
  }
  if (isVersion(depRefPart)) {
    dep.currentRawValue = dep.currentValue;
    dep.currentValue = depRefPart;
    dep.datasource = GithubTagsDatasource.id;
    dep.versioning = npmVersioningId;
    dep.packageName = githubOwnerRepo;
    dep.pinDigests = false;
  } else if (
    regEx(/^[0-9a-f]{7}$/).test(depRefPart) ||
    regEx(/^[0-9a-f]{40}$/).test(depRefPart)
  ) {
    dep.currentRawValue = dep.currentValue;
    dep.currentValue = null;
    dep.currentDigest = depRefPart;
    dep.datasource = GithubTagsDatasource.id;
    dep.versioning = npmVersioningId;
    dep.packageName = githubOwnerRepo;
  } else {
    // <protocol>://[<user>[:<password>]@]<hostname>[:<port>][:][/]<path>[#<commit-ish> | #semver:<semver>]
    // https://docs.npmjs.com/cli/v10/configuring-npm/package-json#git-urls-as-dependencies
    const len = 7; // length of 'semver:'
    const maybeVersion = depRefPart.substring(len);

    if (depRefPart.startsWith('semver:') && isValid(maybeVersion)) {
      dep.currentRawValue = dep.currentValue;
      dep.currentValue = maybeVersion;
      dep.datasource = GithubTagsDatasource.id;
      dep.versioning = npmVersioningId;
      dep.packageName = githubOwnerRepo;
      dep.pinDigests = false;
    } else {
      dep.skipReason = 'unversioned-reference';
      return dep;
    }
  }
  dep.sourceUrl = `https://github.com/${githubOwnerRepo}`;
  dep.gitRef = true;
  return dep;
}

export function getExtractedConstraints(
  deps: PackageDependency[],
): Partial<Record<ConstraintName, string>> {
  const extractedConstraints: Partial<Record<ConstraintName, string>> = {};
  const constraints: ConstraintName[] = [
    'bun',
    'node',
    'yarn',
    'npm',
    'pnpm',
    'vscode',
  ];
  for (const dep of deps) {
    if (
      !dep.skipReason &&
      (dep.depType === 'engines' || dep.depType === 'packageManager') &&
      dep.depName &&
      isConstraintName(dep.depName) &&
      constraints.includes(dep.depName) &&
      isString(dep.currentValue)
    ) {
      extractedConstraints[dep.depName] = dep.currentValue;
    }
  }
  return extractedConstraints;
}