// ============================================================================
// INSTAGRAM PLATFORM ADAPTER
// ============================================================================
//
// Instagram uses two API surfaces:
//   1. REST API (/api/v1/direct_v2/) — simpler, works for inbox listing
//   2. GraphQL (/api/graphql) — what the web app uses, needed for thread messages
//
// Auth: CSRF token from csrftoken cookie + x-ig-app-id header.
// The app ID (936619743392459) is hard-coded in the Instagram web app.
//
// ⚠️  STRICTEST anti-detection of all platforms. Instagram actively monitors
//     for automated access. Keep delays high, volumes low.
//
// ⚠️  VOLATILE: GraphQL doc_ids change with Instagram deploys.
//
// Verified: 2026-06-19 via HAR capture on instagram.com/direct
// ============================================================================

import type {
  PlatformAdapter,
  ApiEndpoint,
  Conversation,
  Message,
  Participant,
} from "../index.js";

// ── Constants ─────────────────────────────────────────────────────────────

/** Instagram web app ID — hard-coded in their JS bundle */
export const IG_APP_ID = "936619743392459";

/**
 * ⚠️  VOLATILE — these doc_ids change when Instagram deploys new code.
 * Capture new IDs from Network tab on instagram.com/direct.
 * Filter by "graphql" and read `fb_api_req_friendly_name` + `doc_id` in the payload.
 *
 * ⚠️  THREAD-ID TRAP (the #1 cause of "GraphQL returns HTML / 0 messages"):
 *     The REST inbox gives each thread a long `thread_id`
 *     (e.g. "340282366841710301244259535260865788759"). GraphQL thread-fetch
 *     and message-send do NOT accept that — they want the short `thread_fbid` /
 *     `ig_thread_igid` (e.g. "1360243288701783"). The thread payload returns
 *     BOTH (`thread_id` ↔ `thread_fbid`/`id`), so capture `thread_fbid` to drive
 *     GraphQL. The REST per-thread endpoint, by contrast, takes the long
 *     `thread_id` directly — which is why it's the reliable read path.
 */
export const DOC_IDS = {
  /** PolarisDirectInboxQuery — lists conversations */
  inboxQuery: "27228858046797698",
  /** IGDSlideAsyncFetchAndInsertIGDViewerThreadQuery — fetches a thread's messages
   *  (keyed by `thread_fbid`). Observed live 2026-06-21. */
  threadFetch: "27110549851904846",
  /** IGDirectTextSendMutation — sends a text message (keyed by `ig_thread_igid`).
   *  Observed live 2026-06-21. */
  textSend: "26911679871773184",
  /** @deprecated IGDThreadDetailQuery — returned HTML as of 2026-06-21 (stale).
   *  Kept for reference; use `threadFetch` or the REST per-thread endpoint. */
  threadDetail: "27530161873341603",
} as const;

// ── Raw API Types ─────────────────────────────────────────────────────────

/** REST inbox response (/api/v1/direct_v2/inbox/) */
export interface InstagramInboxResponse {
  inbox: {
    threads: InstagramRawThread[];
    has_older: boolean;
    unseen_count: number;
  };
  pending_requests_total: number;
}

export interface InstagramRawThread {
  thread_id: string;
  thread_title: string;
  users: InstagramRawUser[];
  items: InstagramRawItem[];
  last_activity_at: string; // epoch microseconds as string
  read_state: number;
  is_group: boolean;
  named: boolean;
}

export interface InstagramRawUser {
  pk: number | string;
  username: string;
  full_name: string;
  profile_pic_url: string;
  is_verified: boolean;
}

export interface InstagramRawItem {
  item_id: string;
  user_id: number;
  timestamp: string; // epoch microseconds as string
  item_type: "text" | "media" | "reel_share" | "link" | "like" | "action_log" | string;
  text?: string;
  media?: { image_versions2?: { candidates: Array<{ url: string; width: number }> } };
  link?: { text: string; link_url: string };
}

/** GraphQL thread detail response */
export interface InstagramThreadDetailResponse {
  data: {
    get_slide_thread_nullable: {
      as_ig_direct_thread: {
        slide_messages: {
          edges: Array<{
            node: InstagramRawGraphQLMessage;
          }>;
        };
      };
    };
  };
}

export interface InstagramRawGraphQLMessage {
  message_id?: string;
  /** the IGDSlideAsyncFetch query returns `id` rather than `message_id` */
  id?: string;
  sender_fbid: string;
  sender?: {
    user_dict?: {
      username: string;
      full_name: string;
    };
    name?: string;
  };
  /** Present for TEXT + reactions ("🔥"). Empty for shares/stories. */
  text_body: string;
  /** Human-readable summary of EVERY message, incl. non-text ones —
   *  e.g. "You: 🔥", "You: replied to your story". The best fallback when
   *  `text_body` is empty. Note the leading "You: " / "<name>: " prefix. */
  igd_snippet?: string;
  timestamp_ms: string; // epoch ms as string
  /** Observed: TEXT, MONTAGE_SHARE_XMA (story reply/reaction), and others. */
  content_type: "TEXT" | "MEDIA" | "LINK" | "MONTAGE_SHARE_XMA" | string;
  content?: { __typename?: string; text_body?: string };
}

// ── Normalization ─────────────────────────────────────────────────────────

export function normalizeParticipant(user: InstagramRawUser): Participant {
  return {
    id: String(user.pk),
    name: user.full_name || user.username,
    username: user.username,
    avatarUrl: user.profile_pic_url,
    profileUrl: `https://www.instagram.com/${user.username}/`,
  };
}

export function normalizeConversation(
  thread: InstagramRawThread,
): Conversation {
  const participants = thread.users.map(normalizeParticipant);
  const firstItem = thread.items[0];

  const lastMessage: Message | null = firstItem
    ? {
        id: firstItem.item_id,
        senderId: String(firstItem.user_id),
        text: firstItem.text ?? "",
        timestamp: new Date(Number(firstItem.timestamp) / 1000).toISOString(),
        type: firstItem.item_type === "text" ? "text" : "other",
      }
    : null;

  return {
    platform: "instagram",
    conversationId: thread.thread_id,
    conversationType: thread.is_group ? "group_dm" : "dm",
    name: thread.named
      ? thread.thread_title
      : participants.map((p) => p.name || p.username).join(", "),
    participants,
    lastMessage,
    lastActivityAt: new Date(
      Number(thread.last_activity_at) / 1000,
    ).toISOString(),
    unreadCount: 0, // REST API doesn't reliably return per-thread unread
  };
}

export function normalizeMessage(msg: InstagramRawGraphQLMessage): Message {
  // text_body covers TEXT + reactions; fall back to igd_snippet (strip the
  // "You: " / "<name>: " prefix) for shares/stories so nothing renders empty.
  const snippet = msg.igd_snippet?.replace(/^[^:]{1,40}:\s/, "");
  return {
    id: msg.message_id ?? msg.id ?? "",
    senderId: String(msg.sender_fbid),
    senderName:
      msg.sender?.user_dict?.full_name ??
      msg.sender?.user_dict?.username ??
      msg.sender?.name,
    text: msg.text_body || snippet || `[${msg.content_type ?? "message"}]`,
    timestamp: new Date(Number(msg.timestamp_ms)).toISOString(),
    type: msg.content_type === "TEXT" ? "text" : "other",
  };
}

// ── Adapter Definition ────────────────────────────────────────────────────

const listConversations: ApiEndpoint = {
  name: "direct_v2/inbox (REST)",
  method: "GET",
  urlTemplate: "https://www.instagram.com/api/v1/direct_v2/inbox/",
  headers: {
    "x-csrftoken": "{csrfToken}",
    "x-ig-app-id": IG_APP_ID,
    accept: "application/json",
  },
  description:
    "REST endpoint for listing DM threads. Returns threads with participant " +
    "info and the most recent item per thread. Simpler than GraphQL and " +
    "proven working as of June 2026.",
  rateLimiting:
    "HIGH RISK. Instagram is the strictest platform. Do not call more than " +
    "once per 5 minutes. Single sync per session is safest.",
  verification: {
    status: "live_verified",
    lastChecked: "2026-06-21",
    source: "hydra_runtime",
    notes: "Used by Hydra extension for inbox reads; keep volume very low.",
  },
};

const fetchMessages: ApiEndpoint = {
  name: "IGDSlideAsyncFetchAndInsertIGDViewerThreadQuery (GraphQL)",
  method: "POST",
  urlTemplate: "https://www.instagram.com/api/graphql",
  headers: {
    "x-csrftoken": "{csrfToken}",
    "x-ig-app-id": IG_APP_ID,
    "x-fb-friendly-name": "IGDSlideAsyncFetchAndInsertIGDViewerThreadQuery",
    "x-asbd-id": "359341",
    "content-type": "application/x-www-form-urlencoded",
    accept: "*/*",
  },
  bodyTemplate: {
    doc_id: DOC_IDS.threadFetch,
    variables: JSON.stringify({
      thread_fbid: "{threadFbid}", // ⚠️ NOT the long REST thread_id — see DOC_IDS note
      min_uq_seq_id: "{cursor}",
      __relay_internal__pv__IGDPinnedThreadsRenderEnabledGKrelayprovider: true,
      __relay_internal__pv__IGDMaxUnreadMessagesCountrelayprovider: 5,
      __relay_internal__pv__PolarisAIGMAccountLabelEnabledrelayprovider: false,
      __relay_internal__pv__IGDThreadListActionsEnabledGKrelayprovider: true,
    }),
    fb_api_req_friendly_name: "IGDSlideAsyncFetchAndInsertIGDViewerThreadQuery",
  },
  description:
    "GraphQL thread-fetch. Returns get_slide_thread_nullable.as_ig_direct_thread" +
    ".slide_messages.edges[].node. Keyed by thread_fbid (short id), NOT the long " +
    "REST thread_id. doc_id is VOLATILE. In practice the REST per-thread endpoint " +
    "(fetchMessagesREST) is more reliable because we already have the thread_id.",
  rateLimiting:
    "VERY HIGH RISK. Space requests 2-5 seconds apart. " +
    "Max 5 threads per sync. Unusual patterns trigger account warnings.",
  verification: {
    status: "documented",
    lastChecked: "2026-06-21",
    source: "manual_capture",
    notes: "Documented from capture; REST per-thread endpoint is preferred when long thread_id is available.",
  },
};

const sendMessage: ApiEndpoint = {
  name: "IGDirectTextSendMutation (GraphQL, WRITE)",
  method: "POST",
  urlTemplate: "https://www.instagram.com/api/graphql",
  headers: {
    "x-csrftoken": "{csrfToken}",
    "x-ig-app-id": IG_APP_ID,
    "x-fb-friendly-name": "IGDirectTextSendMutation",
    "x-fb-lsd": "{lsd}", // required for writes; read from the page's config
    "x-asbd-id": "359341",
    "content-type": "application/x-www-form-urlencoded",
    accept: "*/*",
  },
  bodyTemplate: {
    doc_id: DOC_IDS.textSend,
    fb_dtsg: "{fbDtsg}", // required CSRF-style token for writes, from page config
    variables: JSON.stringify({
      ig_thread_igid: "{threadFbid}", // the short thread_fbid, same as fetch
      offline_threading_id: "{otid}", // client-generated 19-digit id
      text: { sensitive_string_value: "{text}" },
      send_attribution: "igd_web_chat_tab:in_thread",
      recipient_igids: null,
      mentioned_user_ids: [],
    }),
    fb_api_req_friendly_name: "IGDirectTextSendMutation",
  },
  description:
    "WRITE. Sends a text DM. Executes in the page context (same origin/session) " +
    "so it's indistinguishable from the user. Requires fb_dtsg + x-fb-lsd from the " +
    "page config. Response: { xig_direct_text_send_with_slide_messaging_response: " +
    "{ message_id, timestamp_ms } }. Gate behind explicit user approval.",
  rateLimiting:
    "MAXIMUM RISK. Writes are the most heavily monitored action. Human cadence " +
    "only — one message at a time, on explicit approval. Never bulk-send.",
  verification: {
    status: "experimental",
    lastChecked: "2026-06-21",
    source: "manual_capture",
    notes: "Documented for completeness. Do not treat as product-safe without a fresh controlled send test.",
  },
};

export const instagramAdapter: PlatformAdapter = {
  platform: "instagram",
  name: "Instagram",
  color: "#E1306C",
  emoji: "📷",

  auth: {
    requiredTokens: ["csrfToken"],
    extractionMethod:
      "Content script on *.instagram.com extracts csrftoken cookie value.",
    sources: [
      {
        type: "cookie",
        name: "csrfToken",
        selector: "csrftoken",
        description: "The csrftoken cookie. Used as x-csrftoken header.",
      },
    ],
  },

  endpoints: {
    listConversations,
    fetchMessages,
    sendMessage,
    // REST per-thread — the RELIABLE read path (keyed by the long thread_id we
    // already have from the inbox). Prefer this over the GraphQL fetch.
    fetchMessagesREST: {
      name: "direct_v2/threads/{threadId} (REST, primary read)",
      method: "GET",
      urlTemplate:
        "https://www.instagram.com/api/v1/direct_v2/threads/{threadId}/",
      headers: {
        "x-csrftoken": "{csrfToken}",
        "x-ig-app-id": IG_APP_ID,
        accept: "application/json",
      },
      description:
        "Per-thread messages, keyed by the long thread_id from the inbox. " +
        "Returns thread.items[] with item_type (text, reel_share, story_share, " +
        "like, media…). Non-text items carry no `text` — label them by item_type. " +
        "More reliable than GraphQL because we already hold the thread_id.",
      rateLimiting: "Space 2-5s apart, max 5 threads per sync.",
      verification: {
        status: "live_verified",
        lastChecked: "2026-06-21",
        source: "hydra_runtime",
        notes: "Preferred Hydra read path for full thread fetches because it uses the inbox's long thread_id.",
      },
    },
  },

  antiDetection: {
    minDelayMs: 2000,
    maxDelayMs: 5000,
    maxMessageThreads: 5,
    notes:
      "Instagram is the STRICTEST platform. They actively detect automation. " +
      "NEVER inject DOM elements. NEVER expose web-accessible resources. " +
      "NEVER modify the Instagram UI. Keep volume extremely low. " +
      "A spike from 5 DMs/day to 50 will trigger algorithmic flags. " +
      "The x-ig-app-id header is REQUIRED — requests without it are rejected.",
  },

  buildDeepLink: (conv) => {
    return `https://instagram.com/direct/t/${conv.conversationId}`;
  },

  lastVerified: "2026-06-21",
  volatileIds: DOC_IDS,
  changelog: [
    {
      date: "2026-06-21",
      description:
        "Live capture: IGDThreadDetailQuery (27530161873341603) now returns HTML " +
        "(stale). Current thread-fetch is IGDSlideAsyncFetchAndInsertIGDViewerThread" +
        "Query (27110549851904846), keyed by thread_fbid — NOT the long REST " +
        "thread_id (the #1 fetch bug). Documented the REST per-thread endpoint as " +
        "the reliable read path, the thread_id↔thread_fbid mapping, igd_snippet as " +
        "the non-text label source, and added the IGDirectTextSendMutation write " +
        "endpoint (26911679871773184).",
    },
    {
      date: "2026-06-19",
      description:
        "Initial adapter. REST for inbox, GraphQL for thread messages. " +
        "Both verified working. GraphQL doc_ids captured from HAR.",
    },
  ],
};