// Packages
const { readFileSync } = require('fs');
const publicSuffixList = require('psl');
const minimist = require('minimist');
const chalk = require('chalk');

// Ours
const promptBool = require('../lib/utils/input/prompt-bool');
const exit = require('./utils/exit');
const copy = require('./copy');
const toHost = require('./to-host');
const resolve4 = require('./dns');
const isZeitWorld = require('./is-zeit-world');
const { DOMAIN_VERIFICATION_ERROR } = require('./errors');
const Now = require('./');

const argv = minimist(process.argv.slice(2), {
  boolean: ['no-clipboard'],
  alias: { 'no-clipboard': 'C' }
});

const isTTY = process.stdout.isTTY;
const clipboard = !argv['no-clipboard'];
const domainRegex = /^((?=[a-z0-9-]{1,63}\.)(xn--)?[a-z0-9]+(-[a-z0-9]+)*\.)+[a-z]{2,63}$/;

module.exports = class Alias extends Now {
  async ls(deployment) {
    if (deployment) {
      const target = await this.findDeployment(deployment);

      if (!target) {
        const err = new Error(
          `Aliases not found by "${deployment}". Run ${chalk.dim('`now alias ls`')} to see your aliases.`
        );
        err.userError = true;
        throw err;
      }

      return this.listAliases(target.uid);
    }

    return this.listAliases();
  }

  async rm(_alias) {
    return this.retry(async bail => {
      const res = await this._fetch(`/now/aliases/${_alias.uid}`, {
        method: 'DELETE'
      });

      if (res.status === 403) {
        return bail(new Error('Unauthorized'));
      }

      if (res.status !== 200) {
        const err = new Error('Deletion failed. Try again later.');
        throw err;
      }
    });
  }

  async findDeployment(deployment) {
    const list = await this.list();

    let key;
    let val;

    if (/\./.test(deployment)) {
      val = toHost(deployment);
      key = 'url';
    } else {
      val = deployment;
      key = 'uid';
    }

    const depl = list.find(d => {
      if (d[key] === val) {
        if (this._debug) {
          console.log(`> [debug] matched deployment ${d.uid} by ${key} ${val}`);
        }

        return true;
      }

      // Match prefix
      if (`${val}.now.sh` === d.url) {
        if (this._debug) {
          console.log(`> [debug] matched deployment ${d.uid} by url ${d.url}`);
        }

        return true;
      }

      return false;
    });

    return depl;
  }

  async updatePathBasedroutes(alias, rules) {
    alias = await this.maybeSetUpDomain(alias);
    return this.upsertPathAlias(alias, rules);
  }

  async upsertPathAlias(alias, rules) {
    return this.retry(async (bail, attempt) => {
      if (this._debug) {
        console.time(`> [debug] /now/aliases #${attempt}`);
      }

      const rulesData = this.readRulesFile(rules);
      const ruleCount = rulesData.rules.length;
      const res = await this._fetch(`/now/aliases`, {
        method: 'POST',
        body: { alias, rules: rulesData.rules }
      });

      const body = await res.json();
      body.ruleCount = ruleCount;
      if (this._debug) {
        console.timeEnd(`> [debug] /now/aliases #${attempt}`);
      }

      // 409 conflict is returned if it already exists
      if (res.status === 409) {
        return { uid: body.error.uid };
      }
      if (res.status === 422) {
        return body;
      }

      // No retry on authorization problems
      if (res.status === 403) {
        const code = body.error.code;

        if (code === 'custom_domain_needs_upgrade') {
          const err = new Error(
            `Custom domains are only enabled for premium accounts. Please upgrade by running ${chalk.gray('`')}${chalk.cyan('now upgrade')}${chalk.gray('`')}.`
          );
          err.userError = true;
          return bail(err);
        }

        if (code === 'alias_in_use') {
          const err = new Error(
            `The alias you are trying to configure (${chalk.underline(chalk.bold(alias))}) is already in use by a different account.`
          );
          err.userError = true;
          return bail(err);
        }

        if (code === 'forbidden') {
          const err = new Error(
            'The domain you are trying to use as an alias is already in use by a different account.'
          );
          err.userError = true;
          return bail(err);
        }

        return bail(new Error('Authorization error'));
      }

      // All other errors
      if (body.error) {
        const code = body.error.code;

        if (code === 'cert_missing') {
          console.log(
            `> Provisioning certificate for ${chalk.underline(chalk.bold(alias))}`
          );

          try {
            await this.createCert(alias);
          } catch (err) {
            // We bail to avoid retrying the whole process
            // of aliasing which would involve too many
            // retries on certificate provisioning
            return bail(err);
          }

          // Try again, but now having provisioned the certificate

          return this.upsertPathAlias(alias, rules);
        }

        if (code === 'cert_expired') {
          console.log(
            `> Renewing certificate for ${chalk.underline(chalk.bold(alias))}`
          );

          try {
            await this.createCert(alias, { renew: true });
          } catch (err) {
            return bail(err);
          }
        }

        return bail(new Error(body.error.message));
      }

      // The two expected succesful cods are 200 and 304
      if (res.status !== 200 && res.status !== 304) {
        throw new Error('Unhandled error');
      }

      return body;
    });
  }

  readRulesFile(rules) {
    try {
      const rulesJson = readFileSync(rules, 'utf8');
      return JSON.parse(rulesJson);
    } catch (err) {
      console.error(`Reading rules file ${rules} failed: ${err}`);
    }
  }

  async set(deployment, alias) {
    const depl = await this.findDeployment(deployment);
    if (!depl) {
      const err = new Error(
        `Deployment not found by "${deployment}". Run ${chalk.dim('`now ls`')} to see your deployments.`
      );
      err.userError = true;
      throw err;
    }

    const aliasDepl = (await this.listAliases()).find(e => e.alias === alias);
    if (aliasDepl && aliasDepl.rules) {
      if (isTTY) {
        try {
          const msg = `> Path alias excists with ${aliasDepl.rules.length} rule${aliasDepl.rules.length > 1 ? 's' : ''}.\n` +
            `> Are you sure you want to update ${alias} to be a normal alias?\n`;

          const confirmation = await promptBool(msg);

          if (!confirmation) {
            console.log('\n> Aborted');
            return exit(1);
          }
        } catch (err) {
          console.log(err);
        }
      } else {
        console.log(
          `Overwriting path alias with ${aliasDepl.rules.length} rule${aliasDepl.rules.length > 1 ? 's' : ''} to be a normal alias.`
        );
      }
    }

    alias = await this.maybeSetUpDomain(alias);

    const newAlias = await this.createAlias(depl, alias);
    if (!newAlias) {
      throw new Error(
        `Unexpected error occurred while setting up alias: ${JSON.stringify(newAlias)}`
      );
    }
    const { created, uid } = newAlias;
    if (created) {
      const pretty = `https://${alias}`;
      const output = `${chalk.cyan('> Success!')} Alias created ${chalk.dim(`(${uid})`)}:\n${chalk.bold(chalk.underline(pretty))} now points to ${chalk.bold(`https://${depl.url}`)} ${chalk.dim(`(${depl.uid})`)}`;
      if (isTTY && clipboard) {
        let append;
        try {
          await copy(pretty);
          append = '[copied to clipboard]';
        } catch (err) {
          append = '';
        } finally {
          console.log(`${output} ${append}`);
        }
      } else {
        console.log(output);
      }
    } else {
      console.log(
        `${chalk.cyan('> Success!')} Alias already exists ${chalk.dim(`(${uid})`)}.`
      );
    }
  }

  createAlias(depl, alias) {
    return this.retry(async (bail, attempt) => {
      if (this._debug) {
        console.time(
          `> [debug] /now/deployments/${depl.uid}/aliases #${attempt}`
        );
      }

      const res = await this._fetch(`/now/deployments/${depl.uid}/aliases`, {
        method: 'POST',
        body: { alias }
      });

      const body = await res.json();
      if (this._debug) {
        console.timeEnd(
          `> [debug] /now/deployments/${depl.uid}/aliases #${attempt}`
        );
      }

      // 409 conflict is returned if it already exists
      if (res.status === 409) {
        return { uid: body.error.uid };
      }

      // No retry on authorization problems
      if (res.status === 403) {
        const code = body.error.code;

        if (code === 'custom_domain_needs_upgrade') {
          const err = new Error(
            `Custom domains are only enabled for premium accounts. Please upgrade by running ${chalk.gray('`')}${chalk.cyan('now upgrade')}${chalk.gray('`')}.`
          );
          err.userError = true;
          return bail(err);
        }

        if (code === 'alias_in_use') {
          const err = new Error(
            `The alias you are trying to configure (${chalk.underline(chalk.bold(alias))}) is already in use by a different account.`
          );
          err.userError = true;
          return bail(err);
        }

        if (code === 'forbidden') {
          const err = new Error(
            'The domain you are trying to use as an alias is already in use by a different account.'
          );
          err.userError = true;
          return bail(err);
        }

        return bail(new Error('Authorization error'));
      }

      // All other errors
      if (body.error) {
        const code = body.error.code;

        if (code === 'deployment_not_found') {
          return bail(new Error('Deployment not found'));
        }

        if (code === 'cert_missing') {
          console.log(
            `> Provisioning certificate for ${chalk.underline(chalk.bold(alias))}`
          );

          try {
            await this.createCert(alias);
          } catch (err) {
            // We bail to avoid retrying the whole process
            // of aliasing which would involve too many
            // retries on certificate provisioning
            return bail(err);
          }

          // Try again, but now having provisioned the certificate
          return this.createAlias(depl, alias);
        }

        if (code === 'cert_expired') {
          console.log(
            `> Renewing certificate for ${chalk.underline(chalk.bold(alias))}`
          );

          try {
            await this.createCert(alias, { renew: true });
          } catch (err) {
            return bail(err);
          }
        }

        return bail(new Error(body.error.message));
      }

      // The two expected succesful cods are 200 and 304
      if (res.status !== 200 && res.status !== 304) {
        throw new Error('Unhandled error');
      }

      return body;
    });
  }

  async setupRecord(domain, name) {
    await this.setupDomain(domain);

    if (this._debug) {
      console.log(`> [debug] Setting up record "${name}" for "${domain}"`);
    }

    const type = name === '' ? 'ALIAS' : 'CNAME';
    return this.retry(async (bail, attempt) => {
      if (this._debug) {
        console.time(`> [debug] /domains/${domain}/records #${attempt}`);
      }

      const res = await this._fetch(`/domains/${domain}/records`, {
        method: 'POST',
        body: {
          type,
          name: name === '' ? name : '*',
          value: 'alias.zeit.co'
        }
      });

      if (this._debug) {
        console.timeEnd(`> [debug] /domains/${domain}/records #${attempt}`);
      }

      if (res.status === 403) {
        return bail(new Error('Unauthorized'));
      }

      const body = await res.json();

      if (res.status !== 200) {
        throw new Error(body.error.message);
      }

      return body;
    });
  }

  async maybeSetUpDomain(alias) {
    // Make alias lowercase
    alias = alias.toLowerCase();

    // Trim leading and trailing dots
    // for example: `google.com.` => `google.com`
    alias = alias.replace(/^\.+/, '').replace(/\.+$/, '');
    // Evaluate the alias
    if (/\./.test(alias)) {
      alias = toHost(alias);
    } else {
      if (this._debug) {
        console.log(`> [debug] suffixing \`.now.sh\` to alias ${alias}`);
      }

      alias = `${alias}.now.sh`;
    }

    if (!domainRegex.test(alias)) {
      const err = new Error(`Invalid alias "${alias}"`);
      err.userError = true;
      throw err;
    }

    if (!/\.now\.sh$/.test(alias)) {
      console.log(
        `> ${chalk.bold(chalk.underline(alias))} is a custom domain.`
      );
      console.log(
        `> Verifying the DNS settings for ${chalk.bold(chalk.underline(alias))} (see ${chalk.underline('https://zeit.world')} for help)`
      );

      const _domain = publicSuffixList.parse(alias).domain;
      const _domainInfo = await this.getDomain(_domain);
      const domainInfo = _domainInfo && !_domainInfo.error
        ? _domainInfo
        : undefined;
      const { domain, nameservers } = domainInfo
        ? { domain: _domain }
        : await this.getNameservers(alias);
      const usingZeitWorld = domainInfo
        ? !domainInfo.isExternal
        : isZeitWorld(nameservers);
      let skipDNSVerification = false;

      if (this._debug) {
        if (domainInfo) {
          console.log(
            `> [debug] Found domain ${domain} with verified:${domainInfo.verified}`
          );
        } else {
          console.log(
            `> [debug] Found domain ${domain} and nameservers ${nameservers}`
          );
        }
      }

      if (!usingZeitWorld && domainInfo) {
        if (domainInfo.verified) {
          skipDNSVerification = true;
        } else if (domainInfo.uid) {
          const { verified, created } = await this.setupDomain(domain, {
            isExternal: true
          });
          if (!(created && verified)) {
            const e = new Error(
              `> Failed to verify the ownership of ${domain}, please refer to 'now domain --help'.`
            );
            e.userError = true;
            throw e;
          }
          console.log(
            `${chalk.cyan('> Success!')} Domain ${chalk.bold(chalk.underline(domain))} verified`
          );
        }
      }

      try {
        if (!skipDNSVerification) {
          await this.verifyOwnership(alias);
        }
      } catch (err) {
        if (err.userError) {
          // A user error would imply that verification failed
          // in which case we attempt to correct the dns
          // configuration (if we can!)
          try {
            if (usingZeitWorld) {
              console.log(
                `> Detected ${chalk.bold(chalk.underline('zeit.world'))} nameservers! Configuring records.`
              );
              const record = alias.substr(0, alias.length - domain.length);

              // Lean up trailing and leading dots
              const _record = record.replace(/^\./, '').replace(/\.$/, '');
              const _domain = domain.replace(/^\./, '').replace(/\.$/, '');

              if (_record === '') {
                await this.setupRecord(_domain, '*');
              }

              await this.setupRecord(_domain, _record);

              this.recordSetup = true;
              console.log('> DNS Configured! Verifying propagation…');

              try {
                await this.retry(() => this.verifyOwnership(alias), {
                  retries: 10,
                  maxTimeout: 8000
                });
              } catch (err2) {
                const e = new Error(
                  '> We configured the DNS settings for your alias, but we were unable to ' +
                    "verify that they've propagated. Please try the alias again later."
                );
                e.userError = true;
                throw e;
              }
            } else {
              console.log(
                `> Resolved IP: ${err.ip ? `${chalk.underline(err.ip)} (unknown)` : chalk.dim('none')}`
              );
              console.log(
                `> Nameservers: ${nameservers && nameservers.length ? nameservers
                      .map(ns => chalk.underline(ns))
                      .join(', ') : chalk.dim('none')}`
              );
              throw err;
            }
          } catch (e) {
            if (e.userError) {
              throw e;
            }

            throw err;
          }
        } else {
          throw err;
        }
      }

      if (!usingZeitWorld && !skipDNSVerification) {
        if (this._debug) {
          console.log(
            `> [debug] Trying to register a non-ZeitWorld domain ${domain} for the current user`
          );
        }

        const { uid, verified, created } = await this.setupDomain(domain, {
          isExternal: true
        });
        if (!(created && verified)) {
          const e = new Error(
            `> Failed to verify the ownership of ${domain}, please refer to 'now domain --help'.`
          );
          e.userError = true;
          throw e;
        }
        console.log(
          `${chalk.cyan('> Success!')} Domain ${chalk.bold(chalk.underline(domain))} ${chalk.dim(`(${uid})`)} added`
        );
      }

      console.log(`> Verification ${chalk.bold('OK')}!`);
    }
    return alias;
  }

  verifyOwnership(domain) {
    return this.retry(async bail => {
      const targets = await resolve4('alias.zeit.co');

      if (targets.length <= 0) {
        return bail(new Error('Unable to resolve alias.zeit.co'));
      }

      let ips = [];

      try {
        ips = await resolve4(domain);
      } catch (err) {
        if (
          err.code === 'ENODATA' ||
          err.code === 'ESERVFAIL' ||
          err.code === 'ENOTFOUND'
        ) {
          // Not errors per se, just absence of records
          if (this._debug) {
            console.log(`> [debug] No records found for "${domain}"`);
          }

          const err = new Error(DOMAIN_VERIFICATION_ERROR);
          err.userError = true;
          return bail(err);
        }
        throw err;
      }

      if (ips.length <= 0) {
        const err = new Error(DOMAIN_VERIFICATION_ERROR);
        err.userError = true;
        return bail(err);
      }

      for (const ip of ips) {
        if (targets.indexOf(ip) === -1) {
          const err = new Error(
            `The domain ${domain} has an A record ${chalk.bold(ip)} that doesn't resolve to ${chalk.bold(chalk.underline('alias.zeit.co'))}.\n> ` +
              DOMAIN_VERIFICATION_ERROR
          );
          err.ip = ip;
          err.userError = true;
          return bail(err);
        }
      }
    });
  }
};