// ============================================================================
// iMESSAGE PLATFORM ADAPTER
// ============================================================================
//
// iMessage is unique — there's no API to call. Instead, we read directly
// from the SQLite database at ~/Library/Messages/chat.db.
//
// Requires Full Disk Access (FDA) on macOS.
//
// The Tauri app handles this in Rust via rusqlite. This adapter documents
// the database schema and normalization logic so the community can help
// maintain it as Apple changes the schema across macOS versions.
//
// Write: via AppleScript (`tell application "Messages" to send...`)
// Read: direct SQLite queries against chat.db
//
// Verified: 2026-06-19 on macOS 26.3 (Sequoia)
// ============================================================================

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

// ── Database Schema ───────────────────────────────────────────────────────

/**
 * Key tables in ~/Library/Messages/chat.db:
 *
 * chat
 *   - ROWID: integer primary key
 *   - chat_identifier: string (phone number or email, e.g. "+1234567890")
 *   - display_name: string (group chat name, often empty for DMs)
 *   - style: integer (43 = DM, 45 = group)
 *   - last_read_message_timestamp: integer (epoch nanoseconds / 1e9)
 *
 * message
 *   - ROWID: integer primary key
 *   - text: string (message body)
 *   - handle_id: integer → handle.ROWID
 *   - is_from_me: integer (0 or 1)
 *   - date: integer (Core Data timestamp: seconds since 2001-01-01 + nanoseconds)
 *   - date_read: integer
 *   - cache_has_attachments: integer
 *   - associated_message_type: integer (reactions, tapbacks)
 *
 * handle
 *   - ROWID: integer primary key
 *   - id: string (phone number or email)
 *   - service: string ("iMessage" or "SMS")
 *
 * chat_message_join
 *   - chat_id: integer → chat.ROWID
 *   - message_id: integer → message.ROWID
 *
 * chat_handle_join
 *   - chat_id: integer → chat.ROWID
 *   - handle_id: integer → handle.ROWID
 *
 * attachment
 *   - ROWID: integer
 *   - filename: string (path to file, often ~/Library/Messages/Attachments/...)
 *   - mime_type: string
 *
 * message_attachment_join
 *   - message_id: integer → message.ROWID
 *   - attachment_id: integer → attachment.ROWID
 */

/** SQL query for fetching recent conversations */
export const CONVERSATIONS_QUERY = `
  SELECT
    c.ROWID as chat_id,
    c.chat_identifier,
    c.display_name,
    c.style,
    MAX(m.date) as last_message_date,
    COUNT(DISTINCT m.ROWID) as message_count
  FROM chat c
  JOIN chat_message_join cmj ON cmj.chat_id = c.ROWID
  JOIN message m ON m.ROWID = cmj.message_id
  WHERE m.date > :since_date
  GROUP BY c.ROWID
  ORDER BY last_message_date DESC
  LIMIT :limit
`;

/** SQL query for fetching messages in a chat */
export const MESSAGES_QUERY = `
  SELECT
    m.ROWID as message_id,
    m.text,
    m.is_from_me,
    m.date,
    m.date_read,
    m.associated_message_type,
    h.id as handle_id,
    h.service
  FROM message m
  JOIN chat_message_join cmj ON cmj.message_id = m.ROWID
  LEFT JOIN handle h ON h.ROWID = m.handle_id
  WHERE cmj.chat_id = :chat_id
    AND m.text IS NOT NULL
    AND m.associated_message_type = 0
  ORDER BY m.date DESC
  LIMIT :limit
`;

/** SQL query for getting participants of a chat */
export const PARTICIPANTS_QUERY = `
  SELECT h.id, h.service
  FROM chat_handle_join chj
  JOIN handle h ON h.ROWID = chj.handle_id
  WHERE chj.chat_id = :chat_id
`;

/**
 * Convert a Core Data timestamp to a JS Date.
 * Core Data: seconds since 2001-01-01 00:00:00 UTC
 * With nanosecond component in the decimal part.
 */
export function coreDataTimestampToDate(timestamp: number): Date {
  // Core Data epoch offset from Unix epoch (2001-01-01 in seconds)
  const CORE_DATA_EPOCH = 978307200;
  // Timestamps after 2020 are in nanoseconds (Apple changed this)
  const ts = timestamp > 1e15 ? timestamp / 1e9 : timestamp;
  return new Date((ts + CORE_DATA_EPOCH) * 1000);
}

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

/**
 * Normalize an iMessage chat row into a Conversation.
 * Contact name resolution happens in Rust (macOS Contacts framework).
 */
export function normalizeConversation(row: {
  chat_id: number;
  chat_identifier: string;
  display_name: string | null;
  style: number;
  last_message_date: number;
}): Conversation {
  const isDM = row.style === 43;
  const isGroup = row.style === 45;

  return {
    platform: "imessage",
    conversationId: row.chat_identifier,
    conversationType: isGroup ? "group_dm" : "dm",
    name: row.display_name || row.chat_identifier,
    participants: [
      {
        id: row.chat_identifier,
        name: row.display_name || row.chat_identifier,
        // Contact name resolution happens in Rust via the Contacts framework
      },
    ],
    lastMessage: null, // Filled by message query
    lastActivityAt: coreDataTimestampToDate(row.last_message_date).toISOString(),
    unreadCount: 0, // Would need to compare date_read
  };
}

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

const listConversations: ApiEndpoint = {
  name: "SQLite: chat + message join",
  method: "GET", // Not really HTTP — SQLite query
  urlTemplate: "~/Library/Messages/chat.db",
  headers: {},
  description:
    "Direct SQLite query against chat.db. Joins chat → chat_message_join → message " +
    "to get recent conversations sorted by last activity. Requires Full Disk Access.",
  rateLimiting: "N/A — local database. Can query as often as needed.",
  verification: {
    status: "live_verified",
    lastChecked: "2026-06-19",
    source: "local_platform",
    notes: "Hydra desktop reads this local SQLite source directly after Full Disk Access is granted.",
  },
};

const fetchMessages: ApiEndpoint = {
  name: "SQLite: message + chat_message_join",
  method: "GET",
  urlTemplate: "~/Library/Messages/chat.db",
  headers: {},
  description:
    "Query messages for a specific chat_id. Joins message → chat_message_join, " +
    "left joins handle for sender info. Filters out reactions (associated_message_type = 0).",
  rateLimiting: "N/A — local database.",
  verification: {
    status: "live_verified",
    lastChecked: "2026-06-19",
    source: "local_platform",
    notes: "Hydra desktop local read path; macOS schema details can drift across OS versions.",
  },
};

const sendMessage: ApiEndpoint = {
  name: "AppleScript: Messages.app",
  method: "POST",
  urlTemplate: "osascript",
  headers: {},
  bodyTemplate: {
    script:
      'tell application "Messages" to send "{messageText}" to participant "{handle}" of (first conversation whose id = "{chatId}")',
  },
  description:
    "Send via AppleScript. Requires Messages.app to be running. " +
    "The handle is the phone number or email address.",
  rateLimiting: "Low risk — local operation. But Messages.app can be slow to process.",
  verification: {
    status: "live_verified",
    lastChecked: "2026-06-25",
    source: "local_platform",
    notes: "Hydra executes this locally and updates the action ledger synchronously.",
  },
};

export const imessageAdapter: PlatformAdapter = {
  platform: "imessage",
  name: "iMessage",
  color: "#34C759",
  emoji: "💬",

  auth: {
    requiredTokens: [], // No tokens — requires Full Disk Access instead
    extractionMethod:
      "No browser auth needed. The Tauri app reads ~/Library/Messages/chat.db " +
      "directly via SQLite. Requires Full Disk Access (FDA) granted in " +
      "System Settings → Privacy & Security → Full Disk Access.",
    sources: [
      {
        type: "local_storage",
        name: "chatDb",
        selector: "~/Library/Messages/chat.db",
        description:
          "SQLite database containing all iMessage/SMS history. " +
          "Locked behind FDA permission.",
      },
    ],
  },

  endpoints: {
    listConversations,
    fetchMessages,
    sendMessage,
  },

  antiDetection: {
    minDelayMs: 0,
    maxDelayMs: 0,
    maxMessageThreads: 50, // Local DB, no limits
    notes:
      "No anti-detection needed — this is a local database read. " +
      "The only constraint is FDA permission.",
  },

  buildDeepLink: (conv) => {
    const handle = conv.participants[0]?.id;
    if (handle) return `imessage://${handle}`;
    return undefined;
  },

  lastVerified: "2026-06-19",
  changelog: [
    {
      date: "2026-06-19",
      description:
        "Initial adapter. SQLite schema documented for macOS 26.3. " +
        "Core Data timestamp conversion, conversation + message queries.",
    },
  ],
};