import { ExtPackageJson, License } from "@kksh/api/models"
import * as v from "valibot"
import {
	authenticatedUserIsMemberOfGitHubOrg,
	parseGitHubRepoFromUri,
	userIsPublicMemberOfGitHubOrg
} from "../github"
import type { ExtensionPublishValidationData } from "../models"
import { getInfoFromRekorLog } from "../sigstore"
import { getRawFileFromGitHub, getTarballSize } from "../utils"
import {
	NpmPkgMetadata,
	NpmPkgVersionMetadata,
	NpmSearchResultObject,
	NpmSearchResults,
	Provenance
} from "./models"

export * from "./models"

/**
 * Get the full metadata of an npm package
 * @param pkgName
 * @returns
 */
export function getFullNpmPackageInfo(pkgName: string): Promise<NpmPkgMetadata | null> {
	return fetch(`https://registry.npmjs.org/${pkgName}`).then((res) => (res.ok ? res.json() : null))
}

/**
 * Fetch the package.json data of an npm package
 * @param pkgName
 * @param version
 * @returns
 */
export function getNpmPackageInfoByVersion(
	pkgName: string,
	version: string
): Promise<NpmPkgVersionMetadata | null> {
	return fetch(`https://registry.npmjs.org/${pkgName}/${version}`).then((res) =>
		res.ok ? res.json() : null
	)
}

/**
 * Get the provenance of an npm package
 * If a package has no provenance, return null
 * @param pkgName
 * @param version
 * @returns
 */
export function getNpmPkgProvenance(pkgName: string, version: string): Promise<Provenance | null> {
	return fetch(`https://www.npmjs.com/package/${pkgName}/v/${version}/provenance`)
		.then((res) => res.json())
		.catch((err) => null)
}

/**
 * List all packages under a scope
 * @example
 * To get package names under a scope, you can do:
 * ```ts
 * (await listPackagesOfMaintainer("huakunshen")).map((pkg) => pkg.package.name)
 * ```
 * @param username npm organization or username
 * @returns
 */
export function listPackagesOfMaintainer(username: string): Promise<NpmSearchResultObject[]> {
	return fetch(`https://registry.npmjs.org/-/v1/search?text=maintainer:${username}&size=250`, {
		headers: {
			"sec-fetch-dest": "document"
		}
	})
		.then((res) => res.json())
		.then((res) => v.parse(NpmSearchResults, res).objects)
}

export function listPackagesOfScope(scope: string): Promise<NpmSearchResultObject[]> {
	return fetch(`https://registry.npmjs.org/-/v1/search?text=${scope}&size=250`, {
		headers: {
			"sec-fetch-dest": "document"
		}
	})
		.then((res) => res.json())
		.then((res) => v.parse(NpmSearchResults, res).objects)
}

export function getNpmPackageTarballUrl(
	pkgName: string,
	version: string
): Promise<string | undefined> {
	return getNpmPackageInfoByVersion(pkgName, version).then((res) => res?.dist?.tarball)
}

export function npmPackageExists(pkgName: string, version: string): Promise<boolean> {
	return getNpmPackageInfoByVersion(pkgName, version).then((res) => res !== null)
}

/**
 * @param url Sample URL: https://search.sigstore.dev/?logIndex=153252145
 * @returns
 */
function parseLogIdFromSigstoreSearchUrl(url: string): string {
	const urlObj = new URL(url)
	const logIndex = urlObj.searchParams.get("logIndex")
	if (!logIndex) {
		throw new Error("Could not parse log index from sigstore search url")
	}
	return logIndex
}

export async function validateNpmPackageAsKunkunExtension(payload: {
	pkgName: string
	version: string
	githubUsername: string
	tarballSizeLimit?: number
	githubToken?: string
	provenance?: Provenance // provenance API has cors policy, when we run this validation on client side, a provenance should be passed in
}): Promise<{
	error?: string
	data?: ExtensionPublishValidationData
}> {
	/* -------------------------------------------------------------------------- */
	/*                         check if npm package exist                         */
	/* -------------------------------------------------------------------------- */
	const pkgExists = await npmPackageExists(payload.pkgName, payload.version)
	if (!pkgExists) {
		return { error: "Package does not exist" }
	}
	if (!pkgExists) {
		return { error: "NPM package does not exist" }
	}

	/* -------------------------------------------------------------------------- */
	/*                     check if npm package has provenance                    */
	/* -------------------------------------------------------------------------- */
	const provenance =
		payload.provenance ?? (await getNpmPkgProvenance(payload.pkgName, payload.version))
	if (!provenance) {
		return {
			error: "Package doesn't have provenance, not signed by github action"
		}
	}
	if (provenance.sourceCommitUnreachable) {
		return { error: "Package's source commit is unreachable" }
	}
	if (provenance.sourceCommitNotFound) {
		return { error: "Package's source commit is not found" }
	}

	/* -------------------------------------------------------------------------- */
	/*                             get rekor sigstore                             */
	/* -------------------------------------------------------------------------- */
	if (!provenance?.summary.transparencyLogUri) {
		return { error: "Package's rekor log is not found" }
	}
	const logIndex = parseLogIdFromSigstoreSearchUrl(provenance.summary.transparencyLogUri)
	const rekorGit = await getInfoFromRekorLog(logIndex)
	if (rekorGit.commit !== provenance.summary.sourceRepositoryDigest) {
		return { error: "Package's rekor log commit is not the same as the source commit" }
	}

	/* -------------------------------------------------------------------------- */
	/*                  check if npm pkg is linked to github repo                 */
	/* -------------------------------------------------------------------------- */
	const repoUri = provenance.summary.sourceRepositoryUri
	const githubRepo = parseGitHubRepoFromUri(repoUri)

	/* -------------------------------------------------------------------------- */
	/*                            Verify Repo Ownership                           */
	/* -------------------------------------------------------------------------- */
	if (githubRepo.owner !== payload.githubUsername) {
		const isPublicMemeber = await userIsPublicMemberOfGitHubOrg(
			githubRepo.owner,
			payload.githubUsername
		)
		let isOrgMember = false
		if (payload.githubToken) {
			isOrgMember = await authenticatedUserIsMemberOfGitHubOrg(
				githubRepo.owner,
				payload.githubToken
			)
		}
		if (!isPublicMemeber && !isOrgMember) {
			return {
				error: `You (${payload.githubUsername}) are not authorized to publish this package. Only ${githubRepo.owner} or its organization members can publish it.`
			}
		}
	}

	/* -------------------------------------------------------------------------- */
	/*             validate package.json format against latest schema             */
	/* -------------------------------------------------------------------------- */

	const packageJson = await getNpmPackageInfoByVersion(payload.pkgName, payload.version)
	if (!packageJson) {
		return { error: "Could not find package.json in NPM package" }
	}

	if (!packageJson.license) {
		return { error: "Package license field is not found" }
	}

	const licenseParsed = v.safeParse(License, packageJson.license)
	if (!licenseParsed.success) {
		return { error: `Package license field ${packageJson.license} is not valid` }
	}

	const parseResult = v.safeParse(ExtPackageJson, packageJson)
	if (!parseResult.success) {
		console.error(v.flatten(parseResult.issues))
		return { error: `package.json format not valid` }
	}
	/* -------------------------------------------------------------------------- */
	/*                            get more package info                           */
	/* -------------------------------------------------------------------------- */
	const tarballUrl = packageJson.dist?.tarball
	if (!tarballUrl) {
		return { error: "Could not get tarball URL for NPM package" }
	}
	const shasum = packageJson.dist?.shasum
	if (!shasum) {
		return { error: "Could not get shasum for NPM package" }
	}

	const apiVersion = parseResult.output.dependencies?.["@kksh/api"]
	if (!apiVersion) {
		return {
			error: `Extension ${parseResult.output.kunkun.identifier} doesn't not have @kksh/api as a dependency`
		}
	}
	const tarballSize = await getTarballSize(tarballUrl, "GET") // NPM HEAD request doesn't support content-length

	const readmeContent = await getRawFileFromGitHub(
		githubRepo.owner,
		githubRepo.repo,
		provenance.summary.sourceRepositoryDigest,
		parseResult.output.readme ?? "README.md"
	)
	return {
		data: {
			pkgJson: parseResult.output,
			license: licenseParsed.output,
			readmeContent,
			tarballUrl,
			shasum,
			apiVersion,
			tarballSize,
			unpackedSize: packageJson.dist?.unpackedSize,
			rekorLogIndex: logIndex,
			github: {
				githubActionInvocationId: rekorGit.githubActionInvocationId,
				commit: provenance.summary.sourceRepositoryDigest,
				repo: githubRepo.repo,
				owner: githubRepo.owner,
				workflowPath: rekorGit.workflowPath
			}
		}
	}
}