#!/usr/bin/env nu
# detect-provctl.nu - Detect provctl availability and capabilities
# Usage: nu scripts/provisioning/detect-provctl.nu [--verbose]
#
# Returns JSON with provctl information or empty record if not available
# Example output:
# {
#   available: true,
#   path: "/Users/user/Development/provctl",
#   version: "0.1.0",
#   commands: ["start", "stop", "restart", "status", "logs", "deploy"],
#   backends: ["systemd", "launchd", "pidfile"]
# }

def main [--verbose] {
    let result = detect_provctl

    if $verbose {
        if ($result.available) {
            print $"✓ provctl detected at: ($result.path)"
            print $"  Version: ($result.version)"
            print $"  Commands: ($result.commands | str join ', ')"
            print $"  Backends: ($result.backends | str join ', ')"
        } else {
            print "✗ provctl not found"
            print "  Install from: https://github.com/Akasha/provctl"
        }
    }

    $result
}

# Main detection logic
def detect_provctl []: nothing -> record {
    # Check common provctl locations in order
    let locations = [
        # Check if provctl is available in PATH
        (which provctl 2>/dev/null | get path),
        # Check development location (if user is developer)
        "/Users/Akasha/Development/provctl",
        # Check cargo bin
        (($env.HOME? + "/.cargo/bin/provctl")),
        # Check /usr/local/bin
        "/usr/local/bin/provctl",
        # Check /opt/provctl
        "/opt/provctl",
    ]

    let found = (
        $locations
        | where { |loc|
            ($loc != null) and ($loc != "") and (($loc | path exists) or (try { which $loc 2>/dev/null | get path } catch { null }) != null)
        }
        | first
    )

    if ($found == null) {
        return {
            available: false,
            path: null,
            version: null,
            commands: [],
            backends: [],
            reason: "provctl not found in PATH"
        }
    }

    # Try to get version
    let version = (
        try {
            (^$found --version 2>/dev/null | str trim)
        } catch {
            "unknown"
        }
    )

    # Try to get help to detect commands
    let help_output = (
        try {
            (^$found --help 2>/dev/null)
        } catch {
            ""
        }
    )

    # Extract available commands from help text
    let commands = (
        try {
            if ($help_output | str contains "Commands:") {
                let lines = ($help_output | split row "\n")
                let cmd_section = false
                let cmds = []

                for line in $lines {
                    if ($line | str contains "Commands:") {
                        let cmd_section = true
                        continue
                    }

                    if ($cmd_section and ($line | str starts-with "  ")) {
                        let cmd = ($line | str trim | split row " " | first)
                        if ($cmd != "") {
                            $cmds | append $cmd
                        }
                    } else if ($cmd_section and ($line | str trim == "")) {
                        break
                    }
                }

                $cmds
            } else {
                []
            }
        } catch {
            []
        }
    )

    # Detect available backends (platform-specific)
    let backends = (detect_available_backends)

    {
        available: true,
        path: $found,
        version: $version,
        commands: $commands,
        backends: $backends,
        help_available: ($help_output != "")
    }
}

# Detect which backends are available on this system
def detect_available_backends []: nothing -> list {
    mut backends = []

    # Check for systemd (Linux)
    if ((try { which systemctl 2>/dev/null } catch { null }) != null) {
        $backends = ($backends | append "systemd")
    }

    # Check for launchd (macOS)
    if ((try { which launchctl 2>/dev/null } catch { null }) != null) {
        $backends = ($backends | append "launchd")
    }

    # Check for Docker
    if ((try { which docker 2>/dev/null } catch { null }) != null) {
        $backends = ($backends | append "docker")
    }

    # Check for Kubernetes
    if ((try { which kubectl 2>/dev/null } catch { null }) != null) {
        $backends = ($backends | append "kubernetes")
    }

    # PID files are always available
    $backends = ($backends | append "pidfile")

    $backends
}

# Helper to check if a command exists
def command_exists [cmd: string]: nothing -> bool {
    (try { which $cmd 2>/dev/null } catch { null }) != null
}

# Run main if executed directly
# Note: Nushell 0.109+ removed $nu.invocation-dir
# Scripts are executed via `nu script.nu` so we can just call main
main