import * as cache from "@actions/cache";
import * as core from "@actions/core";

import { Events, Inputs, Outputs, State } from "./constants";
import {
    IStateProvider,
    NullStateProvider,
    StateProvider
} from "./stateProvider";
import * as utils from "./utils/actionUtils";

export async function restoreImpl(
    stateProvider: IStateProvider
): Promise<string | undefined> {
    core.setOutput(Outputs.SaveAlways, core.getInput(Inputs.SaveAlways));

    try {
        if (!utils.isCacheFeatureAvailable()) {
            core.setOutput(Outputs.CacheHit, "false");
            return;
        }

        // Validate inputs, this can cause task failure
        if (!utils.isValidEvent()) {
            utils.logWarning(
                `Event Validation Error: The event type ${
                    process.env[Events.Key]
                } is not supported because it's not tied to a branch or tag ref.`
            );
            return;
        }

        const primaryKey = core.getInput(Inputs.Key, { required: true });
        stateProvider.setState(State.CachePrimaryKey, primaryKey);

        const restoreKeys = utils.getInputAsArray(Inputs.RestoreKeys);
        const cachePaths = utils.getInputAsArray(Inputs.Path, {
            required: true
        });
        const enableCrossOsArchive = utils.getInputAsBool(
            Inputs.EnableCrossOsArchive
        );
        const failOnCacheMiss = utils.getInputAsBool(Inputs.FailOnCacheMiss);
        const lookupOnly = utils.getInputAsBool(Inputs.LookupOnly);

        const cacheKey = await cache.restoreCache(
            cachePaths,
            primaryKey,
            restoreKeys,
            { lookupOnly: lookupOnly },
            enableCrossOsArchive
        );

        if (!cacheKey) {
            if (failOnCacheMiss) {
                throw new Error(
                    `Failed to restore cache entry. Exiting as fail-on-cache-miss is set. Input key: ${primaryKey}`
                );
            }
            core.info(
                `Cache not found for input keys: ${[
                    primaryKey,
                    ...restoreKeys
                ].join(", ")}`
            );

            return;
        }

        // Store the matched cache key in states
        stateProvider.setState(State.CacheMatchedKey, cacheKey);

        const isExactKeyMatch = utils.isExactKeyMatch(
            core.getInput(Inputs.Key, { required: true }),
            cacheKey
        );

        core.setOutput(Outputs.CacheHit, isExactKeyMatch.toString());
        if (lookupOnly) {
            core.info(`Cache found and can be restored from key: ${cacheKey}`);
        } else {
            core.info(`Cache restored from key: ${cacheKey}`);
        }

        return cacheKey;
    } catch (error: unknown) {
        core.setFailed((error as Error).message);
    }
}

async function run(
    stateProvider: IStateProvider,
    earlyExit: boolean | undefined
): Promise<void> {
    try {
        await restoreImpl(stateProvider);
    } catch (err) {
        console.error(err);
        if (earlyExit) {
            process.exit(1);
        }
    }

    // node will stay alive if any promises are not resolved,
    // which is a possibility if HTTP requests are dangling
    // due to retries or timeouts. We know that if we got here
    // that all promises that we care about have successfully
    // resolved, so simply exit with success.
    if (earlyExit) {
        process.exit(0);
    }
}

export async function restoreOnlyRun(
    earlyExit?: boolean | undefined
): Promise<void> {
    await run(new NullStateProvider(), earlyExit);
}

export async function restoreRun(
    earlyExit?: boolean | undefined
): Promise<void> {
    await run(new StateProvider(), earlyExit);
}