use std::fs;
use std::path::{Path, PathBuf};
use std::sync::Arc;

use arc_swap::ArcSwap;
use chrono::Utc;
use rpki::rtr::cache::RtrCache;
use rpki::rtr::report::{ReportConfiguration, ReportContext};
use rpki::rtr::server::RtrService;
use rpki::source::pipeline::{
    DataQualityReport, FileFingerprint, PayloadTypeCounts, SlurmRuleCounts, SourceFingerprint,
    SourceLoadReport,
};
use serde_json::Value;

fn test_configuration(report_history_limit: usize) -> ReportConfiguration {
    ReportConfiguration::new(
        300,
        300,
        report_history_limit,
        100,
        false,
        false,
        chrono_tz::Asia::Shanghai,
        (3600, 600, 7200),
    )
}

#[test]
fn write_report_creates_parseable_json() {
    let temp = tempfile::tempdir().unwrap();
    let report_dir = temp.path().join("report");
    let shared_cache = Arc::new(ArcSwap::from_pointee(RtrCache::default()));
    let service = RtrService::new(shared_cache.clone());
    let notifier = service.notifier();
    let context = ReportContext::new(test_configuration(10));

    context.write_or_warn(
        &report_dir,
        "test",
        &shared_cache,
        &notifier,
        &service.stats(),
    );

    let source_report = read_single_report(&report_dir, "rtr-source");
    assert_eq!(source_report["schema_version"], 1);
    assert_eq!(source_report["phase"], "test");
    assert_report_time_offset(&source_report["generated_at"]);
    assert_report_time_offset(&source_report["cache"]["created_at"]);
    assert_eq!(source_report["cache"]["availability"], "ready");
    assert_eq!(source_report["refresh"]["status"], "not_attempted");
    assert!(source_report["source"].is_null());
    assert!(source_report["data_quality"].is_null());

    let runtime_report = read_single_report(&report_dir, "rtr-runtime");
    assert_report_time_offset(&runtime_report["service"]["started_at"]);
    assert_eq!(
        runtime_report["configuration"]["source_refresh_interval_seconds"],
        300
    );
    assert_eq!(runtime_report["configuration"]["report_history_limit"], 10);

    let clients_report = read_single_report(&report_dir, "rtr-clients");
    assert_eq!(clients_report["service"]["max_connections"], 1024);
    assert_eq!(clients_report["service"]["active_connections"], 0);
    assert_eq!(
        clients_report["service"]["connections_by_transport"]["tcp"],
        0
    );
    assert_eq!(
        clients_report["service"]["connections_by_transport"]["tls"],
        0
    );
    assert_eq!(
        clients_report["service"]["connections_by_transport"]["ssh"],
        0
    );
    assert_eq!(
        source_report["cache"]["versions"].as_array().unwrap().len(),
        3
    );
    assert_eq!(
        source_report["cache"]["versions"][2]["snapshot"]["total"],
        0
    );
    assert_eq!(
        source_report["cache"]["memory"]["delta_payload_counts"][2],
        0
    );
    assert!(source_report["source_fingerprint"].is_null());
    assert_no_temporary_reports(&report_dir);
}

#[test]
fn refresh_failure_preserves_last_successful_source_data() {
    let temp = tempfile::tempdir().unwrap();
    let report_dir = temp.path().join("report");
    let shared_cache = Arc::new(ArcSwap::from_pointee(RtrCache::default()));
    let service = RtrService::new(shared_cache.clone());
    let notifier = service.notifier();
    let context = ReportContext::new(test_configuration(10));
    let source = SourceLoadReport {
        ccr_file: "data/example.ccr".to_string(),
        ccr_file_size_bytes: 123,
        ccr_modified_at: Some(Utc::now()),
        ccr_produced_at: Some("20260615000000Z".to_string()),
        slurm_enabled: true,
        slurm_file_count: 1,
        slurm_files: vec!["policy.slurm".to_string()],
        slurm_version: Some(2),
    };
    let quality = DataQualityReport {
        ccr_input: PayloadTypeCounts {
            total: 11,
            vrp: 10,
            router_key: 0,
            aspa: 1,
        },
        invalid: PayloadTypeCounts::default(),
        before_slurm: PayloadTypeCounts {
            total: 11,
            vrp: 10,
            router_key: 0,
            aspa: 1,
        },
        after_slurm: PayloadTypeCounts {
            total: 10,
            vrp: 9,
            router_key: 0,
            aspa: 1,
        },
        slurm_filters: SlurmRuleCounts {
            prefix: 1,
            router_key: 0,
            aspa: 0,
        },
        slurm_assertions: SlurmRuleCounts::default(),
    };
    context.record_source_fingerprint(SourceFingerprint {
        ccr: FileFingerprint {
            path: "data/example.ccr".to_string(),
            len: 123,
            modified_unix_secs: 1_781_404_800,
        },
        slurm_files: vec![FileFingerprint {
            path: "policy.slurm".to_string(),
            len: 42,
            modified_unix_secs: 1_781_408_400,
        }],
    });

    context.record_refresh_success(Utc::now(), 12, true, source, quality);
    context.record_refresh_failure(Utc::now(), 5, &anyhow::anyhow!("source unavailable"));
    context.write_or_warn(
        &report_dir,
        "refresh_failed",
        &shared_cache,
        &notifier,
        &service.stats(),
    );

    let report = read_single_report(&report_dir, "rtr-source");
    assert_eq!(report["source"]["ccr_file"], "data/example.ccr");
    assert_eq!(
        report["source_fingerprint"]["ccr"]["path"],
        "data/example.ccr"
    );
    assert_eq!(report["source_fingerprint"]["ccr"]["len"], 123);
    assert_report_time_offset(&report["source_fingerprint"]["ccr"]["modified_at"]);
    assert_eq!(
        report["source_fingerprint"]["slurm_files"][0]["path"],
        "policy.slurm"
    );
    assert_report_time_offset(&report["source"]["ccr_modified_at"]);
    assert_eq!(report["data_quality"]["after_slurm"]["total"], 10);
    assert_eq!(report["refresh"]["status"], "failed");
    assert_eq!(report["refresh"]["consecutive_failures"], 1);
    assert_eq!(report["refresh"]["last_error"], "source unavailable");
    assert!(!report["refresh"]["last_success_at"].is_null());
    assert_report_time_offset(&report["refresh"]["last_success_at"]);
}

#[test]
fn rolling_reports_keep_latest_files_per_category() {
    let temp = tempfile::tempdir().unwrap();
    let report_dir = temp.path().join("report");
    let shared_cache = Arc::new(ArcSwap::from_pointee(RtrCache::default()));
    let service = RtrService::new(shared_cache.clone());
    let notifier = service.notifier();
    let context = ReportContext::new(test_configuration(2));

    for phase in ["one", "two", "three"] {
        context.write_or_warn(
            &report_dir,
            phase,
            &shared_cache,
            &notifier,
            &service.stats(),
        );
    }

    assert_eq!(report_files(&report_dir, "rtr-source").len(), 2);
    assert_eq!(report_files(&report_dir, "rtr-clients").len(), 2);
    assert_eq!(report_files(&report_dir, "rtr-runtime").len(), 2);
    assert_no_temporary_reports(&report_dir);
}

#[test]
fn category_writes_only_create_requested_report_type() {
    let temp = tempfile::tempdir().unwrap();
    let report_dir = temp.path().join("report");
    let shared_cache = Arc::new(ArcSwap::from_pointee(RtrCache::default()));
    let service = RtrService::new(shared_cache.clone());
    let notifier = service.notifier();
    let context = ReportContext::new(test_configuration(10));

    context.write_source_or_warn(
        &report_dir,
        "source_only",
        &shared_cache,
        &notifier,
        &service.stats(),
    );
    assert_eq!(report_files(&report_dir, "rtr-source").len(), 1);
    assert_eq!(report_files(&report_dir, "rtr-clients").len(), 0);
    assert_eq!(report_files(&report_dir, "rtr-runtime").len(), 0);

    context.write_clients_or_warn(
        &report_dir,
        "clients_only",
        &shared_cache,
        &notifier,
        &service.stats(),
    );
    assert_eq!(report_files(&report_dir, "rtr-source").len(), 1);
    assert_eq!(report_files(&report_dir, "rtr-clients").len(), 1);
    assert_eq!(report_files(&report_dir, "rtr-runtime").len(), 0);

    context.write_runtime_or_warn(
        &report_dir,
        "runtime_only",
        &shared_cache,
        &notifier,
        &service.stats(),
    );
    assert_eq!(report_files(&report_dir, "rtr-source").len(), 1);
    assert_eq!(report_files(&report_dir, "rtr-clients").len(), 1);
    assert_eq!(report_files(&report_dir, "rtr-runtime").len(), 1);
}

fn assert_report_time_offset(value: &Value) {
    let value = value.as_str().expect("report time should be a string");
    assert!(
        value.ends_with("+08:00"),
        "report time should use +08:00 offset, got {value}"
    );
}

fn read_single_report(report_dir: &Path, prefix: &str) -> Value {
    let files = report_files(report_dir, prefix);
    assert_eq!(files.len(), 1, "expected one {prefix} report");
    serde_json::from_slice(&fs::read(&files[0]).unwrap()).unwrap()
}

fn report_files(report_dir: &Path, prefix: &str) -> Vec<PathBuf> {
    let start = format!("{prefix}-");
    let mut files = fs::read_dir(report_dir)
        .unwrap()
        .map(|entry| entry.unwrap().path())
        .filter(|path| {
            path.file_name()
                .and_then(|name| name.to_str())
                .is_some_and(|name| name.starts_with(&start) && name.ends_with(".json"))
        })
        .collect::<Vec<_>>();
    files.sort();
    files
}

fn assert_no_temporary_reports(report_dir: &Path) {
    let has_temporary = fs::read_dir(report_dir).unwrap().any(|entry| {
        entry
            .unwrap()
            .file_name()
            .to_str()
            .is_some_and(|name| name.ends_with(".tmp"))
    });
    assert!(!has_temporary);
}