// Copyright (c) 2026 Probo Inc <hello@probo.com>.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

package coredata

import (
	"context"
	"fmt"
	"maps"
	"time"

	"github.com/jackc/pgx/v5"
	"go.gearno.de/kit/pg"
	"go.probo.inc/probo/pkg/gid"
	"go.probo.inc/probo/pkg/page"
)

type (
	DetectedTracker struct {
		ID               gid.GID       `db:"id"`
		CookieBannerID   gid.GID       `db:"cookie_banner_id"`
		TrackerPatternID *gid.GID      `db:"tracker_pattern_id"`
		TrackerType      TrackerType   `db:"tracker_type"`
		Identifier       string        `db:"identifier"`
		MaxAgeSeconds    *int          `db:"max_age_seconds"`
		Source           *CookieSource `db:"source"`
		ValueSize        *int          `db:"value_size"`
		InitiatorURL     *string       `db:"initiator_url"`
		InitiatorDomain  *string       `db:"initiator_domain"`
		LastDetectedAt   time.Time     `db:"last_detected_at"`
		CreatedAt        time.Time     `db:"created_at"`
		UpdatedAt        time.Time     `db:"updated_at"`
	}

	DetectedTrackers []*DetectedTracker
)

func (dt *DetectedTracker) CursorKey(field DetectedTrackerOrderField) page.CursorKey {
	switch field {
	case DetectedTrackerOrderFieldInitiatorURL:
		if dt.InitiatorURL == nil {
			return page.NewCursorKey(dt.ID, "")
		}

		return page.NewCursorKey(dt.ID, *dt.InitiatorURL)
	case DetectedTrackerOrderFieldLastDetectedAt:
		return page.NewCursorKey(dt.ID, dt.LastDetectedAt)
	}

	panic(fmt.Sprintf("unsupported order by: %s", field))
}

func (dt *DetectedTracker) Upsert(
	ctx context.Context,
	tx pg.Tx,
	scope Scoper,
) (bool, error) {
	q := `
INSERT INTO detected_trackers (
	id,
	tenant_id,
	cookie_banner_id,
	tracker_pattern_id,
	tracker_type,
	identifier,
	max_age_seconds,
	source,
	value_size,
	initiator_url,
	initiator_domain,
	last_detected_at,
	created_at,
	updated_at
) VALUES (
	@id,
	@tenant_id,
	@cookie_banner_id,
	@tracker_pattern_id,
	@tracker_type,
	@identifier,
	@max_age_seconds,
	@source,
	@value_size,
	@initiator_url,
	@initiator_domain,
	@last_detected_at,
	@created_at,
	@updated_at
)
ON CONFLICT (cookie_banner_id, tracker_type, identifier) DO UPDATE
	SET last_detected_at = EXCLUDED.last_detected_at,
		source = CASE WHEN detected_trackers.source IS NULL OR (
				detected_trackers.source != @source_script AND EXCLUDED.source = @source_script
			) THEN EXCLUDED.source
			ELSE detected_trackers.source
		END,
		initiator_url = COALESCE(EXCLUDED.initiator_url, detected_trackers.initiator_url),
		initiator_domain = COALESCE(EXCLUDED.initiator_domain, detected_trackers.initiator_domain),
		updated_at = EXCLUDED.updated_at
`

	args := pgx.StrictNamedArgs{
		"id":                 dt.ID,
		"tenant_id":          scope.GetTenantID(),
		"cookie_banner_id":   dt.CookieBannerID,
		"tracker_pattern_id": dt.TrackerPatternID,
		"tracker_type":       dt.TrackerType,
		"identifier":         dt.Identifier,
		"max_age_seconds":    dt.MaxAgeSeconds,
		"source":             dt.Source,
		"source_script":      CookieSourceScript,
		"value_size":         dt.ValueSize,
		"initiator_url":      dt.InitiatorURL,
		"initiator_domain":   dt.InitiatorDomain,
		"last_detected_at":   dt.LastDetectedAt,
		"created_at":         dt.CreatedAt,
		"updated_at":         dt.UpdatedAt,
	}

	result, err := tx.Exec(ctx, q, args)
	if err != nil {
		return false, fmt.Errorf("cannot upsert detected tracker: %w", err)
	}

	return result.RowsAffected() > 0, nil
}

func (dts *DetectedTrackers) CountByTrackerPatternID(
	ctx context.Context,
	conn pg.Querier,
	scope Scoper,
	trackerPatternID gid.GID,
) (int, error) {
	q := `
SELECT
	COUNT(id)
FROM
	detected_trackers
WHERE
	%s
	AND tracker_pattern_id = @tracker_pattern_id
`

	q = fmt.Sprintf(q, scope.SQLFragment())

	args := pgx.StrictNamedArgs{"tracker_pattern_id": trackerPatternID}
	maps.Copy(args, scope.SQLArguments())

	row := conn.QueryRow(ctx, q, args)

	var count int
	if err := row.Scan(&count); err != nil {
		return 0, fmt.Errorf("cannot scan count: %w", err)
	}

	return count, nil
}

func (dts *DetectedTrackers) LoadInitiatorDomainsByTrackerPatternID(
	ctx context.Context,
	conn pg.Querier,
	trackerPatternID gid.GID,
	limit int,
) ([]string, error) {
	q := `
SELECT DISTINCT initiator_domain
FROM detected_trackers
WHERE tracker_pattern_id = @tracker_pattern_id
  AND initiator_domain IS NOT NULL
LIMIT @limit;
`

	args := pgx.StrictNamedArgs{
		"tracker_pattern_id": trackerPatternID,
		"limit":              limit,
	}

	rows, err := conn.Query(ctx, q, args)
	if err != nil {
		return nil, fmt.Errorf("cannot load initiator domains: %w", err)
	}

	domains, err := pgx.CollectRows(rows, pgx.RowTo[string])
	if err != nil {
		return nil, fmt.Errorf("cannot collect initiator domains: %w", err)
	}

	return domains, nil
}

func (dts *DetectedTrackers) LoadByTrackerPatternID(
	ctx context.Context,
	conn pg.Querier,
	scope Scoper,
	trackerPatternID gid.GID,
	cursor *page.Cursor[DetectedTrackerOrderField],
) error {
	q := `
SELECT
	id,
	cookie_banner_id,
	tracker_pattern_id,
	tracker_type,
	identifier,
	max_age_seconds,
	source,
	value_size,
	initiator_url,
	initiator_domain,
	last_detected_at,
	created_at,
	updated_at
FROM
	detected_trackers
WHERE
	%s
	AND tracker_pattern_id = @tracker_pattern_id
	AND %s
`

	q = fmt.Sprintf(q, scope.SQLFragment(), cursor.SQLFragment())

	args := pgx.StrictNamedArgs{
		"tracker_pattern_id": trackerPatternID,
	}
	maps.Copy(args, scope.SQLArguments())
	maps.Copy(args, cursor.SQLArguments())

	rows, err := conn.Query(ctx, q, args)
	if err != nil {
		return fmt.Errorf("cannot query detected trackers: %w", err)
	}

	trackers, err := pgx.CollectRows(rows, pgx.RowToAddrOfStructByName[DetectedTracker])
	if err != nil {
		return fmt.Errorf("cannot collect detected trackers: %w", err)
	}

	*dts = trackers

	return nil
}

func (dts *DetectedTrackers) LoadSiblingPatternIDsByInitiatorDomains(
	ctx context.Context,
	conn pg.Querier,
	cookieBannerID gid.GID,
	domains []string,
	excludePatternID gid.GID,
	limit int,
) ([]gid.GID, error) {
	if len(domains) == 0 {
		return nil, nil
	}

	q := `
SELECT DISTINCT tracker_pattern_id
FROM detected_trackers
WHERE cookie_banner_id = @cookie_banner_id
  AND initiator_domain = ANY(@domains)
  AND tracker_pattern_id IS NOT NULL
  AND tracker_pattern_id != @exclude_pattern_id
ORDER BY tracker_pattern_id
LIMIT @limit;
`

	args := pgx.StrictNamedArgs{
		"cookie_banner_id":   cookieBannerID,
		"domains":            domains,
		"exclude_pattern_id": excludePatternID,
		"limit":              limit,
	}

	rows, err := conn.Query(ctx, q, args)
	if err != nil {
		return nil, fmt.Errorf("cannot load sibling pattern ids: %w", err)
	}

	ids, err := pgx.CollectRows(rows, pgx.RowTo[gid.GID])
	if err != nil {
		return nil, fmt.Errorf("cannot collect sibling pattern ids: %w", err)
	}

	return ids, nil
}

// UpdateTrackerPatternID repoints a single detected tracker at another
// pattern. It is the per-row counterpart of RelinkByTrackerPatternID,
// used by the banner-reset rebuild where each detection of a glob moves
// to its own recreated exact pattern.
func (dt *DetectedTracker) UpdateTrackerPatternID(
	ctx context.Context,
	tx pg.Tx,
	scope Scoper,
) error {
	q := `
UPDATE detected_trackers
SET
	tracker_pattern_id = @tracker_pattern_id,
	updated_at = @updated_at
WHERE
	%s
	AND id = @id
`

	q = fmt.Sprintf(q, scope.SQLFragment())

	args := pgx.StrictNamedArgs{
		"id":                 dt.ID,
		"tracker_pattern_id": dt.TrackerPatternID,
		"updated_at":         time.Now(),
	}
	maps.Copy(args, scope.SQLArguments())

	result, err := tx.Exec(ctx, q, args)
	if err != nil {
		return fmt.Errorf("cannot update detected tracker pattern: %w", err)
	}

	if result.RowsAffected() == 0 {
		return ErrResourceNotFound
	}

	return nil
}

func (dts *DetectedTrackers) RelinkByTrackerPatternID(
	ctx context.Context,
	tx pg.Tx,
	scope Scoper,
	sourcePatternID gid.GID,
	targetPatternID gid.GID,
) error {
	q := `
UPDATE detected_trackers
SET
	tracker_pattern_id = @target_pattern_id,
	updated_at = @updated_at
WHERE
	%s
	AND tracker_pattern_id = @source_pattern_id
`

	q = fmt.Sprintf(q, scope.SQLFragment())

	args := pgx.StrictNamedArgs{
		"source_pattern_id": sourcePatternID,
		"target_pattern_id": targetPatternID,
		"updated_at":        time.Now(),
	}
	maps.Copy(args, scope.SQLArguments())

	_, err := tx.Exec(ctx, q, args)
	if err != nil {
		return fmt.Errorf("cannot relink detected trackers to pattern: %w", err)
	}

	return nil
}