package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"time"

	"data-terminal-cloud/internal/alertreceiverconformance"
)

func main() {
	routesPath := flag.String("routes", "", "GET /api/v1/ops/alert-routing-policies JSON")
	testsPath := flag.String("tests", "", "GET /api/v1/ops/alert-delivery-tests JSON")
	incidentPath := flag.String("incident", "", "GET /api/v1/ops/alerts/{id} formal drill JSON")
	receiverPath := flag.String("receiver", "", "alert-receiver-capture-v1 JSON")
	candidateVersion := flag.String("candidate-version", "", "release candidate version")
	buildDigest := flag.String("build-digest", "", "sha256 immutable build digest")
	outputPath := flag.String("output", "", "absolute output report path")
	flag.Parse()
	if *routesPath == "" || *testsPath == "" || *incidentPath == "" || *receiverPath == "" || strings.TrimSpace(*candidateVersion) == "" || strings.TrimSpace(*buildDigest) == "" || !filepath.IsAbs(*outputPath) {
		fmt.Fprintln(os.Stderr, "usage: alert-receiver-conformance -routes routes.json -tests tests.json -incident incident.json -receiver receiver.json -candidate-version VERSION -build-digest sha256:... -output ABSOLUTE.json")
		os.Exit(2)
	}
	routesContent, testsContent, incidentContent, receiverContent, err := readInputs(*routesPath, *testsPath, *incidentPath, *receiverPath)
	if err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(2)
	}
	routes, err := alertreceiverconformance.ParseRoutes(routesContent)
	if err != nil {
		failInput(err)
	}
	tests, err := alertreceiverconformance.ParseTests(testsContent)
	if err != nil {
		failInput(err)
	}
	incident, err := alertreceiverconformance.ParseIncident(incidentContent)
	if err != nil {
		failInput(err)
	}
	capture, err := alertreceiverconformance.ParseCapture(receiverContent)
	if err != nil {
		failInput(err)
	}
	report := alertreceiverconformance.Evaluate(routes, tests, incident, capture, *candidateVersion, *buildDigest, time.Now().UTC())
	report.InputSHA256 = map[string]string{
		"cloud_routes": alertreceiverconformance.SHA256(routesContent), "cloud_tests": alertreceiverconformance.SHA256(testsContent),
		"cloud_incident": alertreceiverconformance.SHA256(incidentContent), "receiver_capture": alertreceiverconformance.SHA256(receiverContent),
	}
	encoded, _ := json.MarshalIndent(report, "", "  ")
	encoded = append(encoded, '\n')
	if err = os.WriteFile(*outputPath, encoded, 0o600); err != nil {
		fmt.Fprintln(os.Stderr, "write alert receiver report:", err)
		os.Exit(2)
	}
	fmt.Printf("alert receiver conformance %s: %s\n", report.Result, *outputPath)
	if report.Result != "PASS" {
		os.Exit(1)
	}
}

func readInputs(paths ...string) ([]byte, []byte, []byte, []byte, error) {
	values := make([][]byte, 4)
	for index, path := range paths {
		content, err := os.ReadFile(path)
		if err != nil {
			return nil, nil, nil, nil, fmt.Errorf("read input %s: %w", filepath.Base(path), err)
		}
		values[index] = content
	}
	return values[0], values[1], values[2], values[3], nil
}

func failInput(err error) {
	fmt.Fprintln(os.Stderr, err)
	os.Exit(2)
}