#!/bin/bash
# Materia Supervisor - Continuous pipeline orchestration
# Inspired by TigerBeetle's CFO supervisor pattern
# https://github.com/tigerbeetle/tigerbeetle/blob/main/src/scripts/cfo_supervisor.sh

set -euo pipefail

# Configuration
readonly CHECK_INTERVAL=900  # 15 minutes
readonly CLI_VERSION_CHECK_INTERVAL=3600  # 1 hour
readonly MATERIA_DIR="/opt/materia"
readonly R2_ARTIFACTS_URL="https://${R2_ENDPOINT}/${R2_ARTIFACTS_BUCKET}"
readonly CLI_ARTIFACT="materia-cli-latest.tar.gz"

# Schedules (cron-style times in UTC)
readonly EXTRACT_SCHEDULE_HOUR=2  # 02:00 UTC
readonly TRANSFORM_SCHEDULE_HOUR=3  # 03:00 UTC

# State tracking
last_extract_run=""
last_transform_run=""
last_cli_check=0

log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $*"
}

log_error() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] ERROR: $*" >&2
}

# Check if CLI needs updating
check_cli_update() {
    local now
    now=$(date +%s)

    # Only check once per hour
    if (( now - last_cli_check < CLI_VERSION_CHECK_INTERVAL )); then
        return 0
    fi

    last_cli_check=$now

    log "Checking for CLI updates..."

    # Download new version
    local temp_file="${MATERIA_DIR}/cli-new.tar.gz"
    if ! curl -fsSL -o "$temp_file" "${R2_ARTIFACTS_URL}/${CLI_ARTIFACT}"; then
        log_error "Failed to download CLI artifact"
        return 1
    fi

    # Compare checksums
    local old_checksum=""
    local new_checksum

    if [ -f "${MATERIA_DIR}/${CLI_ARTIFACT}" ]; then
        old_checksum=$(sha256sum "${MATERIA_DIR}/${CLI_ARTIFACT}" | awk '{print $1}')
    fi

    new_checksum=$(sha256sum "$temp_file" | awk '{print $1}')

    if [ "$old_checksum" = "$new_checksum" ]; then
        log "CLI is up to date"
        rm -f "$temp_file"
        return 0
    fi

    log "New CLI version detected, updating..."

    # Install new version
    mv "$temp_file" "${MATERIA_DIR}/${CLI_ARTIFACT}"

    cd "$MATERIA_DIR"
    rm -rf cli && mkdir -p cli
    tar -xzf "$CLI_ARTIFACT" -C cli/

    if pip3 install --force-reinstall cli/*.whl; then
        log "CLI updated successfully"
        materia version
    else
        log_error "Failed to install CLI"
        return 1
    fi
}

# Check if we should run extract pipeline (daily at specified hour)
should_run_extract() {
    local current_hour
    local current_date

    current_hour=$(date -u +%H)
    current_date=$(date -u +%Y-%m-%d)

    # Only run at the scheduled hour
    if [ "$current_hour" != "$EXTRACT_SCHEDULE_HOUR" ]; then
        return 1
    fi

    # Only run once per day
    if [ "$last_extract_run" = "$current_date" ]; then
        return 1
    fi

    return 0
}

# Check if we should run transform pipeline (daily at specified hour)
should_run_transform() {
    local current_hour
    local current_date

    current_hour=$(date -u +%H)
    current_date=$(date -u +%Y-%m-%d)

    # Only run at the scheduled hour
    if [ "$current_hour" != "$TRANSFORM_SCHEDULE_HOUR" ]; then
        return 1
    fi

    # Only run once per day
    if [ "$last_transform_run" = "$current_date" ]; then
        return 1
    fi

    return 0
}

# Run extract pipeline
run_extract() {
    log "Starting extract pipeline..."

    if materia pipeline run extract; then
        log "Extract pipeline completed successfully"
        last_extract_run=$(date -u +%Y-%m-%d)
    else
        log_error "Extract pipeline failed"
        return 1
    fi
}

# Run transform pipeline
run_transform() {
    log "Starting transform pipeline..."

    if materia pipeline run transform; then
        log "Transform pipeline completed successfully"
        last_transform_run=$(date -u +%Y-%m-%d)
    else
        log_error "Transform pipeline failed"
        return 1
    fi
}

# Main supervisor loop
main() {
    log "Materia supervisor starting..."
    log "Extract schedule: daily at ${EXTRACT_SCHEDULE_HOUR}:00 UTC"
    log "Transform schedule: daily at ${TRANSFORM_SCHEDULE_HOUR}:00 UTC"
    log "Check interval: ${CHECK_INTERVAL}s"

    # Initial CLI check
    check_cli_update || log_error "Initial CLI check failed, continuing anyway"

    while true; do
        # Check for CLI updates
        check_cli_update || true

        # Check and run extract pipeline
        if should_run_extract; then
            run_extract || true
        fi

        # Check and run transform pipeline
        if should_run_transform; then
            run_transform || true
        fi

        sleep "$CHECK_INTERVAL"
    done
}

# Run main loop
main