#!/usr/bin/env bash
# migrate-nbd-to-beans.sh — Migrate nbd tickets to beans
#
# Usage: bash scripts/migrate-nbd-to-beans.sh [project-dir]
# Defaults to current directory if no arg given.
#
# Requirements: beans, jq

set -euo pipefail

PROJECT_DIR="${1:-.}"
PROJECT_DIR="$(cd "$PROJECT_DIR" && pwd)"
NBD_DIR="$PROJECT_DIR/.nbd/tickets"
MAP_FILE="/tmp/nbd_id_map_$(echo "$PROJECT_DIR" | tr '/' '_').tsv"

# ── Preflight ────────────────────────────────────────────────────────────────

if [[ ! -d "$NBD_DIR" ]]; then
    echo "ERROR: No .nbd/tickets directory found in $PROJECT_DIR" >&2
    exit 1
fi

command -v beans >/dev/null 2>&1 || { echo "ERROR: beans not found in PATH" >&2; exit 1; }
command -v jq    >/dev/null 2>&1 || { echo "ERROR: jq not found in PATH" >&2; exit 1; }

# ── Field mappers ─────────────────────────────────────────────────────────────

map_priority() {
    local p="${1:-5}"
    if   [[ "$p" -ge 8 ]]; then echo "critical"
    elif [[ "$p" -eq 7 ]]; then echo "high"
    elif [[ "$p" -ge 5 ]]; then echo "normal"
    elif [[ "$p" -ge 3 ]]; then echo "low"
    else echo "deferred"
    fi
}

map_status() {
    case "$1" in
        todo)        echo "todo"        ;;
        in_progress) echo "in-progress" ;;
        done)        echo "completed"   ;;
        closed)      echo "scrapped"    ;;
        archived)    echo "completed"   ;;
        backlog)     echo "draft"       ;;
        *)           echo "todo"        ;;
    esac
}

map_type() {
    case "$1" in
        project) echo "epic"    ;;
        feature) echo "feature" ;;
        task)    echo "task"    ;;
        bug)     echo "bug"     ;;
        *)       echo "task"    ;;
    esac
}

# ── Parse TOML frontmatter field (string value, strips surrounding quotes) ───

parse_field() {
    local field="$1"
    local file="$2"
    awk -v field="$field" '
        /^\+\+\+$/ { fm_count++; if (fm_count == 2) exit; next }
        fm_count == 1 && $0 ~ "^" field " = " {
            line = $0
            sub("^" field " = \"?", "", line)
            sub("\"?$", "", line)
            print line
            exit
        }
    ' "$file"
}

# ── Extract body (everything after second +++) ────────────────────────────────

extract_body() {
    local file="$1"
    awk '/^\+\+\+$/ { count++; if (count == 2) { body=1; next } } body { print }' "$file"
}

# ── Extract dep IDs from a TOML array string ─────────────────────────────────
# Input:  dependencies = ["abc123", "def456"]
# Output: abc123\ndef456  (one per line)

extract_dep_ids() {
    echo "$1" | grep -oE '[0-9a-f]{6}' || true
}

# ── Init ──────────────────────────────────────────────────────────────────────

echo "==> Initializing beans in $PROJECT_DIR"
(cd "$PROJECT_DIR" && beans init)

# Clear map file: columns are old_id <TAB> new_id <TAB> deps_raw
> "$MAP_FILE"

tickets_created=0
tickets_failed=0
deps_wired=0
warnings=()

# ── Pass 1: Create beans ──────────────────────────────────────────────────────

echo ""
echo "==> Pass 1: Creating beans from nbd tickets"

body_tmp="$(mktemp)"
trap 'rm -f "$body_tmp"' EXIT

for ticket_file in "$NBD_DIR"/*.md; do
    [[ -f "$ticket_file" ]] || continue
    old_id="$(basename "$ticket_file" .md)"

    # Parse frontmatter fields
    title="$(parse_field title "$ticket_file")"
    priority_num="$(parse_field priority "$ticket_file")"
    status_raw="$(parse_field status "$ticket_file")"
    type_raw="$(parse_field ticket_type "$ticket_file")"
    deps_line="$(awk '/^\+\+\+$/ { fm_count++; if (fm_count == 2) exit; next } fm_count == 1 && /^dependencies = / { print; exit }' "$ticket_file")"

    # Map to beans values
    beans_priority="$(map_priority "${priority_num:-5}")"
    beans_status="$(map_status "${status_raw:-todo}")"
    beans_type="$(map_type "${type_raw:-task}")"

    # Write body to temp file to avoid quoting issues
    extract_body "$ticket_file" > "$body_tmp"

    # Create the bean
    result="$(cd "$PROJECT_DIR" && beans create \
        --json \
        --type "$beans_type" \
        --status "$beans_status" \
        --priority "$beans_priority" \
        --body-file "$body_tmp" \
        "$title" 2>&1)" || true

    if new_id="$(echo "$result" | jq -r '.bean.id // .id' 2>/dev/null)" && [[ -n "$new_id" && "$new_id" != "null" ]]; then
        printf '%s\t%s\t%s\n' "$old_id" "$new_id" "$deps_line" >> "$MAP_FILE"
        (( tickets_created++ )) || true
        echo "  ✓ $old_id -> $new_id  [$beans_status/$beans_priority/$beans_type]  $title"
    else
        (( tickets_failed++ )) || true
        warnings+=("WARN: failed to create ticket for nbd/$old_id: $title")
        echo "  ✗ $old_id FAILED: $title"
        echo "    Response: $result"
    fi
done

# ── Pass 2: Wire dependencies ─────────────────────────────────────────────────

echo ""
echo "==> Pass 2: Wiring dependencies"

while IFS=$'\t' read -r old_id new_id deps_line; do
    dep_ids="$(extract_dep_ids "$deps_line")"
    [[ -z "$dep_ids" ]] && continue

    while IFS= read -r dep_old_id; do
        [[ -z "$dep_old_id" ]] && continue

        # Look up the new beans ID for this dependency
        dep_new_id="$(awk -F'\t' -v id="$dep_old_id" '$1 == id { print $2 }' "$MAP_FILE")"

        if [[ -z "$dep_new_id" ]]; then
            warnings+=("WARN: dep $dep_old_id (for $old_id -> $new_id) not found in map — skipped")
            echo "  ! dep $dep_old_id not found in map (for $new_id)"
            continue
        fi

        result="$(cd "$PROJECT_DIR" && beans update "$new_id" --blocked-by "$dep_new_id" --json 2>&1)" || true
        if echo "$result" | jq -e '.bean.id // .id' > /dev/null 2>&1; then
            (( deps_wired++ )) || true
            echo "  ✓ $new_id blocked-by $dep_new_id  (was $old_id blocked-by $dep_old_id)"
        else
            warnings+=("WARN: failed to wire dep $dep_new_id -> $new_id: $result")
            echo "  ✗ failed to wire $dep_new_id -> $new_id"
        fi
    done <<< "$dep_ids"
done < "$MAP_FILE"

# ── Cleanup ───────────────────────────────────────────────────────────────────

echo ""
echo "==> Removing .nbd directory"
rm -rf "$PROJECT_DIR/.nbd"
echo "  Removed $PROJECT_DIR/.nbd"

# ── Summary ───────────────────────────────────────────────────────────────────

echo ""
echo "=========================================="
echo "  Migration complete for: $PROJECT_DIR"
echo "  Tickets created : $tickets_created"
echo "  Tickets failed  : $tickets_failed"
echo "  Deps wired      : $deps_wired"
if [[ ${#warnings[@]} -gt 0 ]]; then
    echo "  Warnings:"
    for w in "${warnings[@]}"; do
        echo "    - $w"
    done
fi
echo "=========================================="