#!/bin/bash
# ============================================================================
# Fleet Dispatch — Shell wrapper for Emacs Control Plane operations
# ============================================================================
#
# Usage:
#   scripts/fleet_dispatch.sh append "Message text"
#   scripts/fleet_dispatch.sh poll [agent_name]
#   scripts/fleet_dispatch.sh claim TASK_ID agent_name
#   scripts/fleet_dispatch.sh complete TASK_ID "Result text"
#   scripts/fleet_dispatch.sh status
#
# Environment:
#   FLEET_DAEMON_HOST    — Bezalel host (default: 159.203.146.185)
#   FLEET_DAEMON_USER    — SSH user (default: root)
#   FLEET_DAEMON_SOCKET  — Emacs socket path (default: /root/.emacs.d/server/bezalel)
#   FLEET_DISPATCH_FILE  — Path to dispatch.org on remote (default: /srv/fleet/workspace/dispatch.org)
# ============================================================================

set -euo pipefail

# ── Configuration ──────────────────────────────────────────────────────────
FLEET_DAEMON_HOST="${FLEET_DAEMON_HOST:-159.203.146.185}"
FLEET_DAEMON_USER="${FLEET_DAEMON_USER:-root}"
FLEET_DAEMON_SOCKET="${FLEET_DAEMON_SOCKET:-/root/.emacs.d/server/bezalel}"
FLEET_DISPATCH_FILE="${FLEET_DISPATCH_FILE:-/srv/fleet/workspace/dispatch.org}"

# Colors
GREEN='\033[0;32m'
CYAN='\033[0;36m'
YELLOW='\033[0;33m'
RED='\033[0;31m'
NC='\033[0m'

# ── Helper: Run emacsclient command on Bezalel ─────────────────────────────
run_emacs() {
    local elisp="$1"
    ssh "${FLEET_DAEMON_USER}@${FLEET_DAEMON_HOST}" \
        "emacsclient -s ${FLEET_DAEMON_SOCKET} -e '${elisp}'" 2>/dev/null
}

# ── Helper: Read dispatch.org via SSH ──────────────────────────────────────
read_dispatch() {
    ssh "${FLEET_DAEMON_USER}@${FLEET_DAEMON_HOST}" \
        "cat ${FLEET_DISPATCH_FILE}" 2>/dev/null
}

# ── Helper: Write dispatch.org via SSH ─────────────────────────────────────
write_dispatch() {
    ssh "${FLEET_DAEMON_USER}@${FLEET_DAEMON_HOST}" \
        "cat > ${FLEET_DISPATCH_FILE}" 2>/dev/null
}

# ── Commands ───────────────────────────────────────────────────────────────

cmd_append() {
    local message="${1:?Usage: fleet_dispatch.sh append \"message\"}"
    local timestamp
    timestamp=$(date -u +"%Y-%m-%d %H:%M:%S UTC")
    
    echo -e "${CYAN}Appending to fleet log...${NC}"
    
    # Use the fleet-append wrapper on Bezalel if available, otherwise emacsclient
    if ssh "${FLEET_DAEMON_USER}@${FLEET_DAEMON_HOST}" "which fleet-append" &>/dev/null; then
        ssh "${FLEET_DAEMON_USER}@${FLEET_DAEMON_HOST}" \
            "fleet-append '${timestamp} — ${message}'"
    else
        run_emacs "(with-current-buffer (find-file-noselect \"${FLEET_DISPATCH_FILE}\") (goto-char (point-max)) (insert \"\\n- ${timestamp} — ${message}\") (save-buffer))"
    fi
    
    echo -e "${GREEN}✓ Appended: ${message}${NC}"
}

cmd_poll() {
    local agent="${1:-}"
    
    echo -e "${CYAN}Polling dispatch.org for tasks...${NC}"
    
    local content
    content=$(read_dispatch)
    
    if [ -z "$content" ]; then
        echo -e "${RED}Could not read dispatch.org${NC}"
        return 1
    fi
    
    # Filter TODO items, optionally by agent
    echo -e "${YELLOW}=== Pending Tasks ===${NC}"
    if [ -n "$agent" ]; then
        echo "$content" | grep -E "^\*\* TODO \[${agent}\]" || echo "  No tasks for ${agent}"
    else
        echo "$content" | grep -E "^\*\* TODO " || echo "  No pending tasks"
    fi
}

cmd_claim() {
    local task_id="${1:?Usage: fleet_dispatch.sh claim TASK_ID agent}"
    local agent="${2:?Usage: fleet_dispatch.sh claim TASK_ID agent}"
    local timestamp
    timestamp=$(date -u +"%Y-%m-%dT%H:%M:%SZ")
    
    echo -e "${CYAN}Claiming task #${task_id} for ${agent}...${NC}"
    
    # Use emacsclient to update the Org heading
    run_emacs "(progn (with-current-buffer (find-file-noselect \"${FLEET_DISPATCH_FILE}\") (org-mode) (goto-char (point-min)) (if (re-search-forward (format \"^\\\\*\\\\* TODO.*#%s\" \"${task_id}\") nil t) (progn (org-todo \"IN_PROGRESS\") (org-set-property \"STARTED\" \"${timestamp}\") (save-buffer) (message \"Task %s claimed\" \"${task_id}\")) (message \"Task %s not found\" \"${task_id}\"))))"
    
    echo -e "${GREEN}✓ Task #${task_id} claimed by ${agent}${NC}"
}

cmd_complete() {
    local task_id="${1:?Usage: fleet_dispatch.sh complete TASK_ID \"result\"}"
    local result="${2:-Completed}"
    local timestamp
    timestamp=$(date -u +"%Y-%m-%d %H:%M")
    
    echo -e "${CYAN}Completing task #${task_id}...${NC}"
    
    run_emacs "(progn (with-current-buffer (find-file-noselect \"${FLEET_DISPATCH_FILE}\") (org-mode) (goto-char (point-min)) (if (re-search-forward (format \"^\\\\*\\\\* IN_PROGRESS.*#%s\" \"${task_id}\") nil t) (progn (org-todo \"DONE\") (org-set-property \"RESULT\" \"${result}\") (org-add-planning-info 'closed (org-current-effective-time)) (save-buffer) (message \"Task %s completed\" \"${task_id}\")) (message \"Task %s not found\" \"${task_id}\"))))"
    
    echo -e "${GREEN}✓ Task #${task_id} completed: ${result}${NC}"
}

cmd_status() {
    echo -e "${CYAN}Fleet Control Plane Status${NC}"
    echo -e "  Host:    ${FLEET_DAEMON_HOST}"
    echo -e "  Socket:  ${FLEET_DAEMON_SOCKET}"
    echo -e "  Dispatch: ${FLEET_DISPATCH_FILE}"
    echo ""
    
    # Test connectivity
    if ssh -o ConnectTimeout=5 "${FLEET_DAEMON_USER}@${FLEET_DAEMON_HOST}" "echo ok" &>/dev/null; then
        echo -e "  SSH:     ${GREEN}✓ reachable${NC}"
    else
        echo -e "  SSH:     ${RED}✗ unreachable${NC}"
        return 1
    fi
    
    # Test emacs daemon
    local daemon_status
    daemon_status=$(run_emacs "(if (server-running-p) \"running\" \"stopped\")" 2>/dev/null || echo "error")
    if [ "$daemon_status" = "\"running\"" ]; then
        echo -e "  Daemon:  ${GREEN}✓ running${NC}"
    else
        echo -e "  Daemon:  ${RED}✗ ${daemon_status}${NC}"
    fi
    
    # Count tasks
    local content
    content=$(read_dispatch 2>/dev/null || echo "")
    if [ -n "$content" ]; then
        local todo_count in_progress_count done_count
        todo_count=$(echo "$content" | grep -c "^\*\* TODO " || echo 0)
        in_progress_count=$(echo "$content" | grep -c "^\*\* IN_PROGRESS " || echo 0)
        done_count=$(echo "$content" | grep -c "^\*\* DONE " || echo 0)
        
        echo -e "  Tasks:   ${YELLOW}${todo_count} TODO${NC}, ${CYAN}${in_progress_count} IN_PROGRESS${NC}, ${GREEN}${done_count} DONE${NC}"
    fi
}

# ── Main ───────────────────────────────────────────────────────────────────

case "${1:-help}" in
    append|log)
        shift
        cmd_append "$@"
        ;;
    poll|check)
        shift
        cmd_poll "$@"
        ;;
    claim)
        shift
        cmd_claim "$@"
        ;;
    complete|done)
        shift
        cmd_complete "$@"
        ;;
    status)
        cmd_status
        ;;
    help|--help|-h)
        echo "Fleet Dispatch — Emacs Control Plane wrapper"
        echo ""
        echo "Usage:"
        echo "  $0 append \"message\"          Append to fleet log"
        echo "  $0 poll [agent]               Check for pending tasks"
        echo "  $0 claim TASK_ID agent        Claim a task"
        echo "  $0 complete TASK_ID \"result\"  Mark task complete"
        echo "  $0 status                     Show control plane status"
        echo ""
        echo "Environment:"
        echo "  FLEET_DAEMON_HOST    Bezalel host (default: 159.203.146.185)"
        echo "  FLEET_DAEMON_USER    SSH user (default: root)"
        echo "  FLEET_DAEMON_SOCKET  Emacs socket (default: /root/.emacs.d/server/bezalel)"
        ;;
    *)
        echo -e "${RED}Unknown command: $1${NC}"
        echo "Run '$0 help' for usage."
        exit 1
        ;;
esac