xbp 10.46.0

use semver::Version;
use std::collections::BTreeMap;
use std::fs;
use std::path::{Path, PathBuf};

use super::adapters::parse_release_version_target;
use super::git_ops::{
    parse_canonical_scoped_release_tag_version, release_tag_family, RELEASE_FLAG_SUFFIXES,
};

/// One git tag mapped into release-docs rows.
#[derive(Debug, Clone)]
pub(crate) struct ReleaseDocEntry {
    pub(crate) tag: String,
    pub(crate) version: Version,
    /// Display version (core + real prerelease/build; not inverted service slug).
    pub(crate) version_label: String,
    pub(crate) date: String,
    /// Service / package / release-family key used for SECURITY.md grouping.
    pub(crate) service: String,
    pub(crate) channel: &'static str,
}

pub(crate) fn sync_release_docs(
    project_root: &Path,
    owner: &str,
    repo: &str,
) -> Result<Vec<PathBuf>, String> {
    let entries: Vec<ReleaseDocEntry> = release_doc_entries(project_root)?;
    // SECURITY.md is always rewritten (heals flat multi-service tables into
    // one table per service / release family).
    let updated_paths = vec![
        sync_changelog(project_root, owner, repo, &entries)?,
        sync_security_policy(project_root, &entries)?,
    ];
    Ok(updated_paths)
}

/// Rewrite `SECURITY.md` into the per-service table layout (full heal/migrate).
///
/// Safe to run anytime; overwrites the previous flat multi-service table shape.
/// Called from release-doc sync and available for explicit heal entrypoints.
#[allow(dead_code)]
pub(crate) fn heal_security_policy(project_root: &Path) -> Result<PathBuf, String> {
    let entries = release_doc_entries(project_root)?;
    sync_security_policy(project_root, &entries)
}

fn sync_changelog(
    project_root: &Path,
    owner: &str,
    repo: &str,
    entries: &[ReleaseDocEntry],
) -> Result<PathBuf, String> {
    let changelog: String = render_changelog(owner, repo, entries);
    let path: PathBuf = project_root.join("CHANGELOG.md");
    fs::write(&path, changelog)
        .map_err(|e| format!("Failed to write {}: {}", path.display(), e))?;
    Ok(path)
}

fn sync_security_policy(
    project_root: &Path,
    entries: &[ReleaseDocEntry],
) -> Result<PathBuf, String> {
    let policy: String = render_security_policy(entries);
    let path: PathBuf = project_root.join("SECURITY.md");
    fs::write(&path, policy).map_err(|e| format!("Failed to write {}: {}", path.display(), e))?;
    Ok(path)
}

fn release_doc_entries(project_root: &Path) -> Result<Vec<ReleaseDocEntry>, String> {
    let output: String = super::run_git_command(
        project_root,
        &[
            "for-each-ref",
            "--sort=-creatordate",
            "--format=%(refname:strip=2)|%(creatordate:short)",
            "refs/tags",
        ],
    )?;

    let mut entries: Vec<ReleaseDocEntry> = Vec::new();
    for line in output.lines() {
        let trimmed: &str = line.trim();
        if trimmed.is_empty() {
            continue;
        }
        let Some((tag_raw, date_raw)) = trimmed.split_once('|') else {
            continue;
        };
        let tag: String = tag_raw.trim().to_string();
        let date: String = date_raw.trim().to_string();
        let Some(entry) = classify_release_tag(&tag, &date) else {
            continue;
        };
        entries.push(entry);
    }
    Ok(entries)
}

/// Map a git tag into a release-doc entry with service family.
///
/// Supported shapes:
/// - `v1.2.3` / `1.2.3` → service `repository`
/// - `athena-js-3.0.4` / `docs-v0.1.1-alpha.1` → service from prefix
/// - inverted legacy `1.14.0-athena-auth` → service from prerelease label
pub(crate) fn classify_release_tag(tag: &str, date: &str) -> Option<ReleaseDocEntry> {
    let tag = tag.trim();
    if tag.is_empty() {
        return None;
    }

    // Prefixed package/service tags: slug-1.2.3 / slug-v1.2.3 / slug-1.2.3-flag
    if looks_like_scoped_tag(tag) {
        let family_raw = release_tag_family(tag);
        let (family, service) = normalize_tag_family(&family_raw);
        if !service.is_empty() && service != "v" {
            if let Some(version) = parse_scoped_tag_version(tag, &family) {
                return Some(ReleaseDocEntry {
                    tag: tag.to_string(),
                    version_label: display_version_label(&version),
                    channel: release_channel(&version),
                    version,
                    date: date.to_string(),
                    service,
                });
            }
            // Fallback: adapters parser for standard slug-semver tags.
            if let Ok((version, _)) = parse_release_version_target(tag) {
                return Some(ReleaseDocEntry {
                    tag: tag.to_string(),
                    version_label: display_version_label(&version),
                    channel: release_channel(&version),
                    version,
                    date: date.to_string(),
                    service,
                });
            }
        }
    }

    // Pure / v-prefixed repository tags, including inverted `1.2.3-service-slug`.
    let normalized = tag.strip_prefix('v').unwrap_or(tag);
    let version = Version::parse(normalized).ok()?;

    if let Some(service) = inverted_service_slug(&version) {
        let mut core = Version::new(version.major, version.minor, version.patch);
        // Keep build metadata for channel; drop service-as-prerelease.
        core.build = version.build.clone();
        return Some(ReleaseDocEntry {
            tag: tag.to_string(),
            version_label: display_version_label(&core),
            channel: release_channel(&core),
            version: core,
            date: date.to_string(),
            service,
        });
    }

    Some(ReleaseDocEntry {
        tag: tag.to_string(),
        version_label: display_version_label(&version),
        channel: release_channel(&version),
        version,
        date: date.to_string(),
        service: "repository".to_string(),
    })
}

fn looks_like_scoped_tag(tag: &str) -> bool {
    // Digit (or `v`+digit) after a non-empty letter prefix ⇒ scoped
    // (athena-js-3.0.0, docs-v0.1.0).
    let family = release_tag_family(tag);
    if family.is_empty() || family == "v" || tag.len() <= family.len() {
        return false;
    }
    let rest = &tag[family.len()..];
    rest.chars()
        .next()
        .map(|c| c.is_ascii_digit() || c == 'v')
        .unwrap_or(false)
}

/// `docs-v` → strip prefix `docs-v`, service `docs`; `athena-js-` → service `athena-js`.
fn normalize_tag_family(family_raw: &str) -> (String, String) {
    // Tags like docs-v0.1.0 yield family `docs-v` from release_tag_family.
    if family_raw.len() > 1 && family_raw.ends_with('v') {
        let without_v = &family_raw[..family_raw.len() - 1];
        let service = without_v.trim_end_matches('-').to_string();
        if !service.is_empty() {
            return (family_raw.to_string(), service);
        }
    }
    (
        family_raw.to_string(),
        family_raw.trim_end_matches('-').to_string(),
    )
}

fn parse_scoped_tag_version(tag: &str, family: &str) -> Option<Version> {
    if let Some(v) = parse_canonical_scoped_release_tag_version(tag, family) {
        return Some(v);
    }
    // Also try family without a trailing `v` (docs- / studio-).
    if family.ends_with('v') && family.len() > 1 {
        let alt = &family[..family.len() - 1];
        if let Some(v) = parse_canonical_scoped_release_tag_version(tag, alt) {
            return Some(v);
        }
        if let Some(mut rest) = tag.strip_prefix(alt) {
            rest = rest.strip_prefix('v').unwrap_or(rest);
            if let Ok(v) = Version::parse(rest) {
                return Some(v);
            }
        }
    }
    let mut rest = tag.strip_prefix(family)?;
    rest = rest.strip_prefix('v').unwrap_or(rest);
    for flag in RELEASE_FLAG_SUFFIXES {
        let suffix = format!("-{flag}");
        if let Some(core) = rest.strip_suffix(suffix.as_str()) {
            if let Ok(mut version) = Version::parse(core) {
                if version.build.is_empty() {
                    version.build = semver::BuildMetadata::new(flag).ok()?;
                }
                return Some(version);
            }
        }
    }
    Version::parse(rest).ok()
}

fn inverted_service_slug(version: &Version) -> Option<String> {
    if version.pre.is_empty() {
        return None;
    }
    let pre = version.pre.as_str();
    // Known channel prereleases are not service names.
    if is_channel_prerelease(pre) {
        return None;
    }
    // Service slugs contain letters (athena-auth, athena-auth-ui).
    if !pre.chars().any(|c| c.is_ascii_alphabetic()) {
        return None;
    }
    Some(pre.to_string())
}

fn is_channel_prerelease(pre: &str) -> bool {
    let lower = pre.to_ascii_lowercase();
    let head = lower.split('.').next().unwrap_or(&lower);
    RELEASE_FLAG_SUFFIXES
        .iter()
        .any(|flag| head == *flag || head.starts_with(&format!("{flag}.")))
        || matches!(
            head,
            "rc" | "preview" | "pre" | "snapshot" | "canary" | "next"
        )
}

fn display_version_label(version: &Version) -> String {
    version.to_string()
}

pub(crate) fn release_channel(version: &Version) -> &'static str {
    let label: String = version.pre.to_string().to_ascii_lowercase();
    let build: String = version.build.as_str().to_ascii_lowercase();
    if label.is_empty() && build.is_empty() {
        "stable"
    } else if label.contains("nightly") || build.contains("nightly") {
        "nightly"
    } else if !label.is_empty() || !build.is_empty() {
        // alpha/beta/exp/build metadata → experimental (unless pure nightly above)
        if build == "stable" && label.is_empty() {
            "stable"
        } else {
            "experimental"
        }
    } else {
        "stable"
    }
}

pub(crate) fn render_changelog(owner: &str, repo: &str, entries: &[ReleaseDocEntry]) -> String {
    let mut out: String = String::new();
    out.push_str("# Changelog\n\n");
    out.push_str("## Unreleased\n\n");
    out.push_str("### Notes\n\n");
    out.push_str("- _No unreleased changes yet._\n\n");

    for (idx, entry) in entries.iter().enumerate() {
        let version_label: &str = &entry.version_label;
        let line = if idx + 1 < entries.len() {
            let prev_tag: &str = &entries[idx + 1].tag;
            format!(
                "## [{}](https://github.com/{}/{}/compare/{}...{}) ({})\n\n",
                version_label, owner, repo, prev_tag, entry.tag, entry.date
            )
        } else {
            format!(
                "## [{}](https://github.com/{}/{}/releases/tag/{}) ({})\n\n",
                version_label, owner, repo, entry.tag, entry.date
            )
        };
        out.push_str(&line);
        out.push_str("- Service: `");
        out.push_str(&entry.service);
        out.push_str("`\n");
        out.push_str("- Release channel: ");
        out.push_str(entry.channel);
        out.push('\n');
        out.push_str("- Tag: `");
        out.push_str(&entry.tag);
        out.push_str("`\n\n");
    }

    out
}

pub(crate) fn render_security_policy(entries: &[ReleaseDocEntry]) -> String {
    let mut out: String = String::new();
    out.push_str("# Security Policy\n\n");
    out.push_str("## Supported Versions\n\n");
    out.push_str(
        "Security support is tracked **per service / package release family**. \
Each table lists versions that currently receive security updates for that unit.\n\n",
    );

    let grouped = group_entries_by_service(entries);

    if grouped.is_empty() {
        out.push_str("### repository\n\n");
        out.push_str("| Version | Channel | Supported |\n");
        out.push_str("| ------- | ------- | --------- |\n");
        out.push_str("| _none yet_ | n/a | :x: |\n\n");
    } else {
        for (service, rows) in grouped {
            out.push_str("### ");
            out.push_str(&service);
            out.push_str("\n\n");
            out.push_str("| Version | Channel | Supported |\n");
            out.push_str("| ------- | ------- | --------- |\n");
            for row in rows {
                out.push_str("| ");
                out.push_str(&row.version_label);
                out.push_str(" | ");
                out.push_str(row.channel);
                out.push_str(" | :white_check_mark: |\n");
            }
            out.push('\n');
        }
    }

    out.push_str("## Reporting a Vulnerability\n\n");
    out.push_str(
        "Report vulnerabilities privately to the maintainers. Include reproduction steps, impact, and affected versions (service + version). You will receive an acknowledgement and triage update as soon as possible.\n",
    );
    out
}

/// Group by service, sort services with `repository` first then alpha, versions newest first.
fn group_entries_by_service(
    entries: &[ReleaseDocEntry],
) -> BTreeMap<String, Vec<ReleaseDocEntry>> {
    let mut map: BTreeMap<String, Vec<ReleaseDocEntry>> = BTreeMap::new();
    for entry in entries {
        map.entry(entry.service.clone())
            .or_default()
            .push(entry.clone());
    }

    for rows in map.values_mut() {
        // Newest first by semver, then tag string.
        rows.sort_by(|a, b| {
            b.version
                .cmp(&a.version)
                .then_with(|| b.tag.cmp(&a.tag))
        });
        // Dedupe identical version_label within a service (keep first = newest tag).
        let mut seen = std::collections::BTreeSet::new();
        rows.retain(|row| seen.insert(row.version_label.clone()));
    }

    // Re-order: repository first via custom key prefix in a new map
    let mut ordered: BTreeMap<String, Vec<ReleaseDocEntry>> = BTreeMap::new();
    if let Some(rows) = map.remove("repository") {
        ordered.insert("repository".to_string(), rows);
    }
    for (k, v) in map {
        ordered.insert(k, v);
    }
    ordered
}

#[cfg(test)]
mod classify_tests {
    use super::*;

    #[test]
    fn classifies_repository_v_tag() {
        let e = classify_release_tag("v4.0.0", "2026-07-01").expect("entry");
        assert_eq!(e.service, "repository");
        assert_eq!(e.version_label, "4.0.0");
        assert_eq!(e.channel, "stable");
    }

    #[test]
    fn classifies_scoped_package_tag() {
        let e = classify_release_tag("athena-js-3.0.4", "2026-07-01").expect("entry");
        assert_eq!(e.service, "athena-js");
        assert_eq!(e.version_label, "3.0.4");
        assert_eq!(e.channel, "stable");
    }

    #[test]
    fn classifies_docs_v_prefix_tag() {
        let e = classify_release_tag("docs-v0.1.1-alpha.1", "2026-07-01").expect("entry");
        assert_eq!(e.service, "docs");
        assert_eq!(e.version_label, "0.1.1-alpha.1");
        assert_eq!(e.channel, "experimental");
    }

    #[test]
    fn classifies_inverted_legacy_service_pre() {
        let e = classify_release_tag("1.14.0-athena-auth", "2026-07-01").expect("entry");
        assert_eq!(e.service, "athena-auth");
        assert_eq!(e.version_label, "1.14.0");
        assert_eq!(e.channel, "stable");
    }

    #[test]
    fn classifies_inverted_ui_pre() {
        let e = classify_release_tag("1.13.2-athena-auth-ui", "2026-07-01").expect("entry");
        assert_eq!(e.service, "athena-auth-ui");
        assert_eq!(e.version_label, "1.13.2");
    }

    #[test]
    fn security_policy_has_per_service_tables() {
        let entries = vec![
            classify_release_tag("v4.0.0", "2026-07-02").unwrap(),
            classify_release_tag("athena-js-3.0.4", "2026-07-01").unwrap(),
            classify_release_tag("1.14.0-athena-auth", "2026-06-01").unwrap(),
        ];
        let security = render_security_policy(&entries);
        assert!(security.contains("### repository"));
        assert!(security.contains("### athena-auth"));
        assert!(security.contains("### athena-js"));
        assert!(security.contains("| 4.0.0 | stable | :white_check_mark: |"));
        assert!(security.contains("| 3.0.4 | stable | :white_check_mark: |"));
        assert!(security.contains("| 1.14.0 | stable | :white_check_mark: |"));
        // Must not dump inverted service name as the version cell.
        assert!(!security.contains("| 1.14.0-athena-auth |"));
    }
}