"use server";

import { PUBLISH_POLICIES, type PublishPolicy } from "yt-dlp-transcript-common/lib/settingsSchema";
import { revalidatePath } from "next/cache";
import { getPaths } from "yt-dlp-transcript-common/lib/paths";
import {
  parseAccent,
  parseAccentSetting,
} from "yt-dlp-transcript-common/lib/accent";
import {
  DEFAULT_ACCENT,
  wordmarkLeadFor,
} from "yt-dlp-transcript-common/lib/brand";
import {
  getSite,
  writeSite,
  deleteSite,
  isValidSiteId,
  parseRelatedSites,
  parseSiteChannels,
  parseSiteUrl,
  type Site,
} from "yt-dlp-transcript-common/lib/site";
import {
  parseSocialLinks,
  type SocialLink,
} from "yt-dlp-transcript-common/lib/settings";
import {
  parseChannelGroups,
  resolveDefaultGroupId,
} from "yt-dlp-transcript-common/lib/channelGroups";
import { migrateToSites } from "yt-dlp-transcript-common/controller/migrateToSites";
import { socialLinksForSave } from "yt-dlp-transcript-common/lib/socialLinks";
import { formValues, type FormState } from "../lib/formState";
import { reportSiteKeysFromForm } from "./lib/reportSiteKeys";

// A failure carries what was submitted, so SiteForm keeps what was typed
// (lib/formState.ts).
export type SaveResult = FormState<{ siteId: string }>;

export async function saveSiteAction(
  _prev: SaveResult | undefined,
  formData: FormData,
): Promise<SaveResult> {
  const values = formValues(formData);
  const siteId = String(formData.get("siteId") ?? "").trim();
  if (!isValidSiteId(siteId)) {
    return {
      ok: false,
      error: "Site ID must be lowercase letters, numbers, and hyphens.",
      values,
    };
  }
  const siteTitle = String(formData.get("siteTitle") ?? "").trim();
  const headerTitle = String(formData.get("headerTitle") ?? "").trim();
  if (!siteTitle) {
    return { ok: false, error: "Site title is required", values };
  }
  if (!headerTitle) {
    return { ok: false, error: "Header title is required", values };
  }
  const siteDescription = String(formData.get("siteDescription") ?? "").trim();
  const homeTagline = String(formData.get("homeTagline") ?? "").trim();
  // The wordmark's heavy lead must be a proper prefix of the header title;
  // lib/siteSchema.ts would silently drop anything else, so say so here.
  const wordmarkLead = String(formData.get("wordmarkLead") ?? "").trim();
  if (wordmarkLead && !wordmarkLeadFor(headerTitle, wordmarkLead)) {
    return {
      ok: false,
      error: `Wordmark lead must be how the header title starts, same case, and shorter than it (e.g. "Jer" for "Jeralyzer") — or left blank.`,
      values,
    };
  }
  // Brand accent: a named id from the radio group, or "custom" + its hex
  // field. The default (Signal) is stored as absent — the two read the same.
  // A bare hex in `accent` (a form from before the radio group) is taken as
  // a custom colour.
  const accentChoice = String(formData.get("accent") ?? "").trim();
  const accentCustomRaw = String(formData.get("accentCustom") ?? "").trim();
  let accent: string | undefined;
  if (accentChoice === "custom") {
    accent = parseAccent(accentCustomRaw);
    if (!accent) {
      return {
        ok: false,
        error: "Custom accent must be a hex color like #cc3366.",
        values,
      };
    }
  } else if (accentChoice) {
    accent = parseAccentSetting(accentChoice);
    if (!accent) {
      return {
        ok: false,
        error: `Unknown brand accent "${accentChoice}".`,
        values,
      };
    }
    if (accent === DEFAULT_ACCENT) accent = undefined;
  }
  const cloudflareProject = String(
    formData.get("cloudflareProject") ?? "",
  ).trim();
  const siteUrlRaw = String(formData.get("siteUrl") ?? "").trim();
  if (siteUrlRaw && !parseSiteUrl(siteUrlRaw)) {
    return {
      ok: false,
      error: "Public URL must be an absolute http(s):// URL, or left blank.",
      values,
    };
  }
  const siteUrl = parseSiteUrl(siteUrlRaw);
  // Listed on the homepage and hub by default: the same opt-out idiom as
  // archives below (an unchecked box sends no key → persisted as false).
  const listed = formData.get("listed") === "on";
  // Who the site is built for (release 17 slice XP): only "private" is kept.
  const audienceRaw = String(formData.get("audience") ?? "public");
  if (audienceRaw !== "public" && audienceRaw !== "private") {
    return { ok: false, error: `Unknown audience "${audienceRaw}".`, values };
  }
  const isPrivate = audienceRaw === "private";
  // The publish lane's policy for this site (release 18). writeSite refuses a
  // deploying policy with no Pages project (sitePublishProblem) and stores a
  // private site's as "build".
  const publishAutoRaw = String(formData.get("publishAuto") ?? "off");
  if (!(PUBLISH_POLICIES as readonly string[]).includes(publishAutoRaw)) {
    return { ok: false, error: `Unknown publish policy "${publishAutoRaw}".`, values };
  }
  const publishAuto = publishAutoRaw as PublishPolicy;
  // Search (opt-out; off = report-only) and the report list, which is not on
  // this form: the stored one is carried over.
  let storedReports: Pick<Site, "reports"> | undefined;
  try {
    storedReports = getSite(siteId, getPaths());
  } catch {
    storedReports = undefined;
  }
  const reportKeys = reportSiteKeysFromForm(formData, storedReports);

  // Hub parent (per-site override of the family default) + PWA opt-in.
  const hubUrlRaw = String(formData.get("hubUrl") ?? "").trim();
  if (hubUrlRaw && !parseSiteUrl(hubUrlRaw)) {
    return {
      ok: false,
      error: "Hub URL must be an absolute http(s):// URL, or left blank.",
      values,
    };
  }
  const hubUrl = parseSiteUrl(hubUrlRaw);
  const pwa = formData.get("pwa") === "on";
  // Archives default on: an unchecked (default-on) box yields no "archives" key
  // → false → persisted as the explicit opt-out.
  const archives = formData.get("archives") === "on";
  // Duplicates default on, same opt-out idiom as archives.
  const duplicates = formData.get("duplicates") === "on";
  // Per-video transcript downloads default on, same opt-out idiom.
  const transcriptDownloads = formData.get("transcriptDownloads") === "on";
  const archiveMaxMBRaw = String(formData.get("archiveMaxMB") ?? "").trim();
  let archiveMaxBytes: number | undefined;
  if (archiveMaxMBRaw) {
    const mb = Number(archiveMaxMBRaw);
    if (!Number.isFinite(mb) || mb < 0) {
      return {
        ok: false,
        error: "Archive size cap must be a non-negative number of MB, or blank.",
        values,
      };
    }
    archiveMaxBytes = Math.floor(mb * 1024 * 1024);
  }

  let relatedSitesInput: unknown;
  try {
    relatedSitesInput = JSON.parse(
      String(formData.get("relatedSitesJson") ?? "[]"),
    );
  } catch {
    return { ok: false, error: "Related sites payload is malformed", values };
  }
  const relatedSites = parseRelatedSites(relatedSitesInput);

  let groupsInput: unknown;
  try {
    groupsInput = JSON.parse(String(formData.get("groupsJson") ?? "[]"));
  } catch {
    return { ok: false, error: "Channel groups payload is malformed", values };
  }
  const groups = parseChannelGroups(groupsInput);
  if (groups.length === 0) {
    return {
      ok: false,
      error: "At least one channel group is required (check ID/name fields)",
      values,
    };
  }
  const defaultGroupIdRaw = String(formData.get("defaultGroupId") ?? "").trim();
  const defaultGroupId = resolveDefaultGroupId(defaultGroupIdRaw, groups);
  if (defaultGroupIdRaw && defaultGroupIdRaw !== defaultGroupId) {
    return {
      ok: false,
      error: `Default group "${defaultGroupIdRaw}" is not among the configured group IDs`,
      values,
    };
  }

  // When inheriting, leave socialLinks undefined so writeSite omits the key and
  // the site falls back to the global default at render time.
  const inheritSocialLinks = formData.get("inheritSocialLinks") === "on";
  let socialLinks: SocialLink[] | undefined;
  if (!inheritSocialLinks) {
    let socialInput: unknown;
    try {
      socialInput = JSON.parse(String(formData.get("socialLinksJson") ?? "[]"));
    } catch {
      return { ok: false, error: "Social links payload is malformed", values };
    }
    const socialParsed = parseSocialLinks(socialInput);
    if (
      Array.isArray(socialInput) &&
      socialParsed.length !== socialInput.length
    ) {
      return {
        ok: false,
        error:
          "Each social link needs a label, URL (http(s)://, mailto:, or /), and SVG.",
        values,
      };
    }
    // A link whose SVG is unchanged from the site's file is kept as it is; a
    // new or edited one is checked (lib/socialLinks.ts socialLinksForSave).
    let stored: SocialLink[] = [];
    try {
      stored = getSite(siteId, getPaths()).socialLinks ?? [];
    } catch {
      stored = [];
    }
    const checked = socialLinksForSave(socialParsed, stored);
    if ("refused" in checked) {
      return {
        ok: false,
        error: `Social link "${checked.refused.label}" has an invalid SVG: ${checked.refused.problem}.`,
        values,
      };
    }
    socialLinks = checked.links;
  }

  let channelsInput: unknown;
  try {
    channelsInput = JSON.parse(String(formData.get("channelsJson") ?? "[]"));
  } catch {
    return {
      ok: false,
      error: "Channel membership payload is malformed",
      values,
    };
  }
  const channels = parseSiteChannels(channelsInput);

  const site: Site = {
    siteId,
    siteTitle,
    siteDescription,
    headerTitle,
    ...(wordmarkLead ? { wordmarkLead } : {}),
    homeTagline,
    ...(socialLinks !== undefined ? { socialLinks } : {}),
    groups,
    defaultGroupId,
    channels,
    ...(accent ? { accent } : {}),
    ...(cloudflareProject ? { cloudflareProject } : {}),
    ...(siteUrl ? { siteUrl } : {}),
    // The Site is rebuilt from the form: a key missing here is dropped on save.
    ...(listed ? {} : { listed: false }),
    ...(isPrivate ? { audience: "private" as const } : {}),
    ...(publishAuto !== "off" ? { publish: { auto: publishAuto } } : {}),
    ...reportKeys,
    ...(hubUrl ? { hubUrl } : {}),
    ...(pwa ? { pwa: true } : {}),
    ...(archives ? {} : { archives: false }),
    ...(duplicates ? {} : { duplicates: false }),
    ...(transcriptDownloads ? {} : { transcriptDownloads: false }),
    ...(archiveMaxBytes !== undefined ? { archiveMaxBytes } : {}),
    ...(relatedSites.length > 0 ? { relatedSites } : {}),
  };
  try {
    await writeSite(site, getPaths());
  } catch (err) {
    return {
      ok: false,
      error: err instanceof Error ? err.message : String(err),
      values,
    };
  }
  revalidatePath("/sites");
  // "layout": the h1 above every tab reads siteTitle, and a literal path would
  // revalidate only the settings page (revalidatePath.md).
  revalidatePath("/sites/[siteId]", "layout");
  return { ok: true, siteId };
}

export type DeleteResult = { ok: true } | { ok: false; error: string };

export async function deleteSiteAction(
  siteId: string,
): Promise<DeleteResult> {
  try {
    await deleteSite(siteId, getPaths());
  } catch (err) {
    return { ok: false, error: err instanceof Error ? err.message : String(err) };
  }
  revalidatePath("/sites");
  return { ok: true };
}

export async function migrateToSitesAction(): Promise<DeleteResult> {
  try {
    await migrateToSites({ paths: getPaths() });
  } catch (err) {
    return { ok: false, error: err instanceof Error ? err.message : String(err) };
  }
  revalidatePath("/sites");
  revalidatePath("/settings");
  return { ok: true };
}