#!/usr/bin/env python3
"""
Massive backfill: March 12 - April 1, 2026
Writes ONLY to 'default' namespace (raw data)
Overlapping chunks - no gaps!
"""
import struct
import urllib.request
import urllib.error
import urllib.parse
import json
import ssl
import snappy
import base64
import time

# Read credentials from environment (see .env)
import os
MIMIR_URL = "https://metrics.vultrlabs.com/prometheus"
MIMIR_USER = os.environ.get("MIMIR_USERNAME", "REPLACE_WITH_MIMIR_USERNAME")
MIMIR_PASS = os.environ.get("MIMIR_PASSWORD", "REPLACE_WITH_MIMIR_PASSWORD")
M3DB_URL = "http://m3coordinator.m3db.svc.cluster.local:7201"

# March 12 to April 1 (full range)
START_TS = 1773273600   # March 12 00:00 UTC
END_TS = 1775052000     # April 1 14:00 UTC
CHUNK_HOURS = 4         # 4-hour chunks
OVERLAP_MINUTES = 30    # 30-min overlap between chunks
STEP = "10s"

METRICS = [
    "vllm:prompt_tokens_total",
    "vllm:generation_tokens_total",
    "DCGM_FI_DEV_GPU_UTIL",
]

def enc(v):
    b = v & 0x7f
    v >>= 7
    r = b""
    while v:
        r += bytes([0x80 | b])
        b = v & 0x7f
        v >>= 7
    return r + bytes([b])

def es(f, d): return enc((f<<3)|2) + enc(len(d)) + d
def ed(f, v): return enc((f<<3)|1) + struct.pack("<d", v)

def build_ts(labels, samples):
    ts = b""
    for n, v in labels.items():
        l = es(1, n.encode()) + es(2, v.encode())
        ts += enc((1<<3)|2) + enc(len(l)) + l
    for t_ms, val in samples:
        s = ed(1, val) + enc((2<<3)|0) + enc(t_ms)
        ts += enc((2<<3)|2) + enc(len(s)) + s
    return ts

def ssl_ctx():
    ctx = ssl.create_default_context()
    ctx.check_hostname = False
    ctx.verify_mode = ssl.CERT_NONE
    return ctx

def mimir_req(path):
    auth = base64.b64encode(f"{MIMIR_USER}:{MIMIR_PASS}".encode()).decode()
    url = f"{MIMIR_URL}{path}"
    req = urllib.request.Request(url)
    req.add_header("Authorization", f"Basic {auth}")
    resp = urllib.request.urlopen(req, context=ssl_ctx(), timeout=300)
    return json.loads(resp.read().decode())

def write_m3db(data):
    c = snappy.compress(data)
    req = urllib.request.Request(f"{M3DB_URL}/api/v1/prom/remote/write", c, method="POST")
    req.add_header("Content-Type", "application/x-protobuf")
    req.add_header("X-Prometheus-Remote-Write-Version", "0.1.0")
    req.add_header("Content-Encoding", "snappy")
    # TARGET ONLY DEFAULT NAMESPACE
    req.add_header("X-M3-Namespace", "default")
    try:
        urllib.request.urlopen(req, timeout=300)
        return True
    except urllib.error.HTTPError as e:
        err = e.read().decode()[:200]
        print(f"  WRITE ERROR {e.code}: {err}")
        return False

print(f"MASSIVE BACKFILL - DEFAULT NAMESPACE ONLY")
print(f"Range: March 12 - April 1, 2026")
print(f"Chunk size: {CHUNK_HOURS}h, Overlap: {OVERLAP_MINUTES}m")
print(f"Metrics: {len(METRICS)}")
print("="*60)

total_samples = 0
start_time = time.time()
chunk_seconds = CHUNK_HOURS * 3600
overlap_seconds = OVERLAP_MINUTES * 60

for metric in METRICS:
    print(f"\n{metric}:")
    metric_samples = 0
    chunk_num = 0
    
    chunk_start = START_TS
    while chunk_start < END_TS:
        chunk_end = min(chunk_start + chunk_seconds, END_TS)
        chunk_num += 1
        
        path = f"/api/v1/query_range?query={urllib.parse.quote(metric)}&start={chunk_start}&end={chunk_end}&step={STEP}"
        
        try:
            data = mimir_req(path)
        except Exception as e:
            print(f"  Chunk {chunk_num}: QUERY FAILED: {e}")
            chunk_start = chunk_end - overlap_seconds
            continue
        
        if data.get("status") != "success":
            print(f"  Chunk {chunk_num}: status={data.get('status')}")
            chunk_start = chunk_end - overlap_seconds
            continue
        
        series = data["data"]["result"]
        samples = sum(len(s["values"]) for s in series)
        
        if samples == 0:
            chunk_start = chunk_end - overlap_seconds
            continue
        
        wr = b""
        for s in series:
            labels = dict(s["metric"])
            labels["cluster"] = "serverless-inference-cluster"
            pts = [(int(float(v[0])*1000), float(v[1])) for v in s["values"]]
            ts = build_ts(labels, pts)
            wr += enc((1<<3)|2) + enc(len(ts)) + ts
        
        if write_m3db(wr):
            metric_samples += samples
            hrs = (chunk_end - chunk_start) / 3600
            print(f"  Chunk {chunk_num}: {samples:,} samples ({hrs:.1f}h) ✓", flush=True)
        
        # Next chunk starts with overlap
        chunk_start = chunk_end - overlap_seconds
    
    total_samples += metric_samples
    print(f"  TOTAL {metric}: {metric_samples:,} samples")

elapsed = time.time() - start_time
print("="*60)
print(f"DONE! {total_samples:,} samples in {elapsed:.1f}s")