#define _CRT_SECURE_NO_WARNINGS
#include "bits/stdc++.h"
using namespace std;
#define all(a) a.begin(), a.end()
const int mod = 1e9 + 7;
const int inv6 = 166666668;
const int inv2 = 500000004;
struct Mint {
    int z;
    Mint() : z(0) {}
    Mint(int _z) : z(_z) {}
    Mint operator-(const Mint& other) const {
        int val = z - other.z + mod;
        if (val >= mod) { val -= mod; }
        return Mint(val);
    }
    Mint operator-(const int& other) const {
        int val = z - other + mod;
        if (val >= mod) { val -= mod; }
        return Mint(val);
    }
    Mint operator+(const Mint& other) const {
        int val = z + other.z;
        if (val >= mod) { val -= mod; }
        return Mint(val);
    }
    Mint operator+(const int& other) const {
        int val = z + other;
        if (val >= mod) { val -= mod; }
        return Mint(val);
    }
    Mint operator*(const Mint& other) const {
        int val = (1ll * z * other.z) % mod;
        return Mint(val);
    }
    Mint operator*(const int& other) const {
        int val = (1ll * z * other) % mod;
        return Mint(val);
    }
};
Mint ari(Mint n) {
    return (n + 1ll) * n * inv2;
}
Mint seg_ari(int l, int r) {
    return ari(r) - ari(l - 1);
}
Mint sqSum(Mint n) {
    return n * (n + 1ll) * (n * 2ll + 1ll) * inv6;
}
Mint seg_sqSum(int l, int r) {
    return sqSum(r) - sqSum(l - 1);
}
struct Node {
    Mint sum[3];
    int push;
    Node() : push(-1) {
        sum[0] = Mint();
        sum[1] = Mint();
        sum[2] = Mint();
    }
    Node operator+(const Node& other) {
        Node res;
        for (int _ = 0; _ < 3; _++) {
            res.sum[_] = sum[_] + other.sum[_];
        }
        return res;
    }
};
struct Segtree {
    int n;
    vector<Node> t;
    Segtree(int _n, vector<int>& a) : n(_n) {
        t.resize(4 * _n);
        build(1, 0, _n - 1, a);
    }
    void build(int v, int tl, int tr, vector<int>& a) {
        if (tl == tr) {
            Mint up(1), pw(tl + 1), val(a[tl]);
            for (int _ = 0; _ < 3; _++) {
                t[v].sum[_] = val * up;
                up = (up * pw);
            }
            return;
        }
        int tm = (tl + tr) / 2;
        build(v * 2, tl, tm, a);
        build(v * 2 + 1, tm + 1, tr, a);
        t[v] = t[v * 2] = t[v * 2 + 1];
    }
    void push(int v, int tl, int tr) {
        if (t[v].push == -1) { return; }
        t[v].sum[0] = Mint(t[v].push) * (tr - tl + 1ll);
        t[v].sum[1] = seg_ari(tl + 1, tr + 1) * t[v].push;
        t[v].sum[2] = seg_sqSum(tl + 1, tr + 1) * t[v].push;
        if (v * 2 + 1 < (int)t.size()) {
            t[v * 2].push = t[v].push;
            t[v * 2 + 1].push = t[v].push;
        }
        t[v].push = -1;
    }
    void update(int v, int tl, int tr, int l, int r, int val) {
        push(v, tl, tr);
        if (tl > r || tr < l) { return; }
        if (tl >= l && tr <= r) {
            t[v].push = val;
            push(v, tl, tr);
            return;
        }
        int tm = (tl + tr) / 2;
        update(v * 2, tl, tm, l, r, val);
        update(v * 2 + 1, tm + 1, tr, l, r, val);
        t[v] = t[v * 2] + t[v * 2];
    }
    void update(int l, int r, int val) {
        update(1, 0, n - 1, l, r, val);
    }
    Node Query(int v, int tl, int tr, int l, int r) {
        push(v, tl, tr);
        if (tl > r || tr < l) { return Node(); }
        if (tl >= l && tr <= r) { return t[v]; }
        int tm = (tl + tr) / 2;
        return Query(v * 2, tl, tm, l, r) + Query(v * 2 + 1, tm + 1, tr, l, r);
    }
    Node Query(int l, int r) {
        return Query(1, 0, n - 1, l, r);
    }
};
signed main() {
#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, q; cin >> n >> q;
    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    Segtree T(n, a);
    auto count_function = [&](int l, int r) {
        Node sm = T.Query(l, r);
        return (sm.sum[0] * l * l - (sm.sum[1] * 2ll * l) + sm.sum[2]).z;
    };
    while (q--) {
        int tp; cin >> tp;
        if (tp == 1) {
            int l, r, x; cin >> l >> r >> x;
            l--, r--;
            T.update(l, r, x);
        }
        if (tp == 2) {
            int l, r; cin >> l >> r;
            l--, r--;
            cout << count_function(l, r) << '\n';
        }
    }
}