# -*- coding: utf-8 -*-
"""Post-migration for 19.0.2.2.0 - Bundle 11.

Back-fills the new x_fc_symptom_class_id M2O on repair.order from the legacy
x_fc_issue_category Char so that existing repairs can immediately be used
with troubleshooting flowcharts. For each distinct (category, issue_category)
text we encounter, we either match an existing symptom.class by lowercase
name OR create a placeholder symptom row tagged 'auto-imported' so a manager
can clean it up later.
"""

import logging
import re

_logger = logging.getLogger(__name__)


def _slug(text):
    return re.sub(r'[^a-z0-9_]+', '_', (text or '').strip().lower()).strip('_') or 'unknown'


def migrate(cr, version):
    if not version:
        return  # fresh install, nothing to back-fill

    # Find every (category_id, issue_category) pair on existing repairs that
    # is not yet linked to a symptom class.
    cr.execute("""
        SELECT DISTINCT x_fc_repair_category_id, x_fc_issue_category
          FROM repair_order
         WHERE x_fc_issue_category IS NOT NULL
           AND x_fc_issue_category <> ''
           AND x_fc_symptom_class_id IS NULL
    """)
    pairs = cr.fetchall()
    if not pairs:
        return

    _logger.info(
        'Bundle 11 migration: back-filling symptom_class for %d distinct '
        '(category, issue_category) pairs', len(pairs),
    )

    for cat_id, issue_text in pairs:
        if not cat_id:
            continue
        code = _slug(issue_text)
        # Try to reuse an existing symptom class by code-or-name on this category.
        cr.execute("""
            SELECT id FROM fusion_repair_symptom_class
             WHERE category_id = %s
               AND (code = %s OR LOWER(name->>'en_US') = LOWER(%s))
             LIMIT 1
        """, (cat_id, code, issue_text))
        row = cr.fetchone()
        if row:
            sym_id = row[0]
        else:
            # Create a placeholder so the M2O isn't lost. Manager renames later.
            display = (issue_text or 'Imported').strip()[:80]
            cr.execute("""
                INSERT INTO fusion_repair_symptom_class
                       (name, code, category_id, sequence, active,
                        description, icon, create_date, write_date, create_uid,
                        write_uid)
                VALUES (%s, %s, %s, %s, %s, %s, %s,
                        NOW(), NOW(), 1, 1)
                RETURNING id
            """, (
                {'en_US': display},
                code,
                cat_id,
                90,
                True,
                'Auto-imported by Bundle 11 migration from legacy '
                'x_fc_issue_category. Review and rename if needed.',
                'fa-exclamation-circle',
            ))
            sym_id = cr.fetchone()[0]
        # Back-fill the M2O on every repair with this pair.
        cr.execute("""
            UPDATE repair_order
               SET x_fc_symptom_class_id = %s
             WHERE x_fc_repair_category_id = %s
               AND x_fc_issue_category = %s
               AND x_fc_symptom_class_id IS NULL
        """, (sym_id, cat_id, issue_text))

    _logger.info('Bundle 11 migration: back-fill complete.')