/*
 * chat_msg.c — сообщения: отправка, DB-операции для chat_sync
 *
 * Вынесено из chat_core.c для уменьшения размера модуля.
 */

#include "chat_core_priv.h"
#include "gui_bridge.h"

#include "../../../src/utun_instance.h"
#include "secure_channel.h"
#include "../../../lib/mem.h"
#include "../../../lib/platform_compat.h"

#include <openssl/sha.h>

/* ─── отправка сообщения (GUI → uasync) ─── */

static int msg_get_prev_chain_hash(const char* tbl, uint8_t out[32]) {
    char sql[128]; snprintf(sql, sizeof(sql),
        "SELECT chain_hash FROM \"%s\" ORDER BY timestamp DESC LIMIT 1", tbl);
    sqlite3_stmt* st = NULL;
    if (sqlite3_prepare_v2(g_cc.db, sql, -1, &st, NULL) != SQLITE_OK) { memset(out,0,32); return -1; }
    if (sqlite3_step(st) == SQLITE_ROW) {
        const void* blob = sqlite3_column_blob(st, 0); int blen = sqlite3_column_bytes(st, 0);
        if (blob && blen == 32) memcpy(out, blob, 32); else memset(out, 0, 32);
    } else { memset(out, 0, 32); }
    sqlite3_finalize(st); return 0;
}

void chat_core_submit_message(struct chat_msg_submit* req) {
    if (!g_cc.initialized) { DEBUG_ERROR(DEBUG_CATEGORY_CONNECTIVITY, "%s: submit before init", CC_ID); return; }
    if (!req) return;

    DEBUG_INFO(DEBUG_CATEGORY_CONNECTIVITY, "%s: SUBMIT ch=%s ct=%s len=%u",
               CC_ID, req->channel_id, req->content_type, req->data_len);

    struct DB_SYNC_INSTANCE* si = si_find(req->channel_id);
    if (!si) { DEBUG_ERROR(DEBUG_CATEGORY_CONNECTIVITY, "%s: no db_sync instance for ch=%s", CC_ID, req->channel_id); return; }

    char json[4096];
    snprintf(json, sizeof(json),
        "{\"n\":%llu,\"ch\":\"%s\",\"ct\":\"%s\",\"d\":\"%.*s\"}",
        (unsigned long long)g_cc.my_node_id, req->channel_id,
        req->content_type, (int)req->data_len, (const char*)req->data);

    uint64_t ts = db_sync_next_timestamp(si);
    uint8_t sig_msg[8192]; size_t soff = 0;
    memcpy(sig_msg + soff, &ts, 8);  soff += 8;
    size_t jl = strlen(json); memcpy(sig_msg + soff, json, jl); soff += jl;
    uint8_t sig[64];
    if (sc_ed25519_sign(g_cc.inst->my_ed25519_privkey, sig_msg, soff, sig) != SC_OK) {
        DEBUG_ERROR(DEBUG_CATEGORY_CONNECTIVITY, "%s: Ed25519 sign failed", CC_ID);
        return;
    }

    int ret = db_sync_insert_signed(si, json, strlen(json), sig, 64, ts);
    if (ret != 0) {
        DEBUG_ERROR(DEBUG_CATEGORY_CONNECTIVITY, "%s: db_sync_insert_signed failed ret=%d", CC_ID, ret);
        return;
    }
}

void chat_core_submit_trampoline(void* arg) { chat_core_submit_message((struct chat_msg_submit*)arg); u_free(arg); }

/* ─── DB-операции для chat_sync ─── */

uint32_t chat_core_count(const char* ch_id) {
    if (!g_cc.initialized) return 0;
    char tbl[80]; msg_table_name(ch_id, tbl, sizeof(tbl));
    char sql[128]; snprintf(sql, sizeof(sql),
        "SELECT COUNT(*) FROM \"%s\"", tbl);
    sqlite3_stmt* stmt = NULL;
    if (sqlite3_prepare_v2(g_cc.db, sql, -1, &stmt, NULL) != SQLITE_OK) return 0;
    uint32_t cnt = 0;
    if (sqlite3_step(stmt) == SQLITE_ROW)
        cnt = (uint32_t)sqlite3_column_int64(stmt, 0);
    sqlite3_finalize(stmt);
    return cnt;
}

int chat_core_chain_hash_at(const char* ch_id, uint32_t pos, uint8_t* hash_out) {
    if (!g_cc.initialized || !hash_out) return -1;
    char tbl[80]; msg_table_name(ch_id, tbl, sizeof(tbl));
    char sql[200]; snprintf(sql, sizeof(sql),
        "SELECT chain_hash FROM \"%s\" ORDER BY timestamp, node_id ASC LIMIT 1 OFFSET ?",
        tbl);
    sqlite3_stmt* stmt = NULL;
    if (sqlite3_prepare_v2(g_cc.db, sql, -1, &stmt, NULL) != SQLITE_OK) {
        memset(hash_out, 0, 32); return -1;
    }
    sqlite3_bind_int64(stmt, 1, (sqlite3_int64)pos);
    if (sqlite3_step(stmt) == SQLITE_ROW) {
        const void* blob = sqlite3_column_blob(stmt, 0);
        int len = sqlite3_column_bytes(stmt, 0);
        if (blob && len == 32) memcpy(hash_out, blob, 32);
        else memset(hash_out, 0, 32);
    } else {
        memset(hash_out, 0, 32);
    }
    sqlite3_finalize(stmt);
    return 0;
}

int chat_core_list_channels(uint8_t* buf, size_t buf_size, size_t* out_len) {
    if (!g_cc.initialized || !buf || !out_len) return -1;
    sqlite3_stmt* stmt = NULL;
    if (sqlite3_prepare_v2(g_cc.db,
            "SELECT channel_id FROM channels ORDER BY created_at ASC",
            -1, &stmt, NULL) != SQLITE_OK) return -1;

    uint8_t* out = buf;
    uint8_t* start = out;
    out += 2;

    uint16_t cnt = 0;
    while (sqlite3_step(stmt) == SQLITE_ROW) {
        const char* ch_id = (const char*)sqlite3_column_text(stmt, 0);
        int ch_len = sqlite3_column_bytes(stmt, 0);
        if (!ch_id || ch_len <= 0 || ch_len > 63) continue;
        size_t need = (size_t)(out - buf) + 1 + (size_t)ch_len;
        if (need > buf_size) break;
        *out++ = (uint8_t)ch_len;
        memcpy(out, ch_id, (size_t)ch_len); out += ch_len;
        cnt++;
    }
    sqlite3_finalize(stmt);

    memcpy(start, &cnt, 2);
    *out_len = (size_t)(out - buf);
    return 0;
}

int chat_core_list_peers(const char* ch_id, uint8_t* buf, size_t buf_size,
                          size_t* out_len) {
    if (!g_cc.initialized || !buf || !out_len) return -1;
    char tbl[80]; peers_table_name(ch_id, tbl, sizeof(tbl));
    char sql[128]; snprintf(sql, sizeof(sql),
        "SELECT node_id FROM \"%s\"", tbl);
    sqlite3_stmt* stmt = NULL;
    if (sqlite3_prepare_v2(g_cc.db, sql, -1, &stmt, NULL) != SQLITE_OK) {
        uint16_t z = 0; memcpy(buf, &z, 2); *out_len = 2; return -1;
    }
    uint16_t cnt = 0;
    uint8_t* out = buf + 2;
    while (sqlite3_step(stmt) == SQLITE_ROW) {
        if ((size_t)(out - buf) + 8 > buf_size) break;
        uint64_t nid = (uint64_t)sqlite3_column_int64(stmt, 0);
        memcpy(out, &nid, 8); out += 8; cnt++;
    }
    sqlite3_finalize(stmt);
    memcpy(buf, &cnt, 2);
    *out_len = (size_t)(out - buf);
    return 0;
}

int chat_core_load_nodeinfo(uint64_t node_id, uint8_t* buf, size_t buf_size,
                             size_t* out_len) {
    if (!g_cc.initialized || !buf || !out_len) return -1;

    sqlite3_stmt* stmt = NULL;
    if (sqlite3_prepare_v2(g_cc.db,
            "SELECT x25519_pubkey, ed25519_pubkey FROM nodes WHERE node_id=?",
            -1, &stmt, NULL) != SQLITE_OK) return -1;
    sqlite3_bind_int64(stmt, 1, (sqlite3_int64)node_id);
    if (sqlite3_step(stmt) != SQLITE_ROW) { sqlite3_finalize(stmt); return -1; }
    const uint8_t* x25519 = (const uint8_t*)sqlite3_column_blob(stmt, 0);
    int x25519_len = sqlite3_column_bytes(stmt, 0);
    const uint8_t* ed25519 = (const uint8_t*)sqlite3_column_blob(stmt, 1);
    int ed25519_len = sqlite3_column_bytes(stmt, 1);

    uint8_t* out = buf;
    if (x25519 && x25519_len == 32) memcpy(out, x25519, 32);
    else memset(out, 0, 32);
    out += 32;
    if (ed25519 && ed25519_len == 32) memcpy(out, ed25519, 32);
    else memset(out, 0, 32);
    out += 32;
    sqlite3_finalize(stmt);

    if (sqlite3_prepare_v2(g_cc.db,
            "SELECT family, protocol, address, port, rtt FROM node_addresses WHERE node_id=?",
            -1, &stmt, NULL) != SQLITE_OK) {
        *out++ = 0; *out_len = (size_t)(out - buf); return 0;
    }
    sqlite3_bind_int64(stmt, 1, (sqlite3_int64)node_id);
    uint8_t* cnt_pos = out; *out++ = 0;
    uint8_t addr_cnt = 0;

    while (sqlite3_step(stmt) == SQLITE_ROW && addr_cnt < 255) {
        int family  = sqlite3_column_int(stmt, 0);
        int proto   = sqlite3_column_int(stmt, 1);
        const uint8_t* addr = (const uint8_t*)sqlite3_column_blob(stmt, 2);
        int addr_len = sqlite3_column_bytes(stmt, 2);
        uint16_t port = (uint16_t)sqlite3_column_int(stmt, 3);
        int16_t rtt   = (int16_t)sqlite3_column_int(stmt, 4);

        if ((size_t)(out - buf) + 7 + (size_t)addr_len > buf_size) break;
        *out++ = (uint8_t)family;
        *out++ = (uint8_t)proto;
        *out++ = (uint8_t)addr_len;
        if (addr_len > 0) { memcpy(out, addr, (size_t)addr_len); out += addr_len; }
        memcpy(out, &port, 2); out += 2;
        memcpy(out, &rtt, 2); out += 2;
        addr_cnt++;
    }
    *cnt_pos = addr_cnt;
    sqlite3_finalize(stmt);

    *out_len = (size_t)(out - buf);
    return 0;
}

/* ─── db_sync callback ─── */

void on_msg_inserted(struct DB_SYNC_INSTANCE* si, uint64_t record_ts, const char* data, size_t len, uint64_t author, void* arg) {
    (void)si; (void)record_ts; (void)data; (void)len; (void)author;
    const char* ch_id = (const char*)arg;
    uint8_t evt[73]; uint8_t cl = (uint8_t)strlen(ch_id); evt[0] = cl; memcpy(evt + 1, ch_id, cl);
    memcpy(evt + 1 + cl, &author, 8);
    gui_bridge_post(GUI_EVT_MSG_RECEIVED, evt, 1 + cl + 8);
}