package models

import (
	"database/sql"
	"strings"
	"time"
)

type JobLog struct {
	ID        int64     `db:"id" json:"id"`
	JobID     int64     `db:"job_id" json:"job_id"`
	Stream    string    `db:"stream" json:"stream"`
	Content   string    `db:"content" json:"content"`
	Timestamp time.Time `db:"timestamp" json:"timestamp"`
}

type JobLogRepository struct {
	db *sql.DB
}

func NewJobLogRepository(db *sql.DB) *JobLogRepository {
	return &JobLogRepository{db: db}
}

func (r *JobLogRepository) InsertBatch(jobID int64, stream string, lines []string) error {
	if len(lines) == 0 {
		return nil
	}
	tx, err := r.db.Begin()
	if err != nil {
		return err
	}
	stmt, err := tx.Prepare("INSERT INTO job_logs (job_id, stream, content) VALUES (?, ?, ?)")
	if err != nil {
		return err
	}
	defer stmt.Close()
	for _, line := range lines {
		if _, err := stmt.Exec(jobID, stream, line); err != nil {
			tx.Rollback()
			return err
		}
	}
	return tx.Commit()
}

func (r *JobLogRepository) GetByJobID(jobID int64, limit, offset int) ([]JobLog, error) {
	if limit <= 0 {
		limit = 1000
	}
	if limit > 10000 {
		limit = 10000
	}
	rows, err := r.db.Query(`
		SELECT id, job_id, stream, content, timestamp
		FROM job_logs WHERE job_id = ?
		ORDER BY id ASC LIMIT ? OFFSET ?`,
		jobID, limit, offset)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var logs []JobLog
	for rows.Next() {
		var l JobLog
		if err := rows.Scan(&l.ID, &l.JobID, &l.Stream, &l.Content, &l.Timestamp); err != nil {
			return nil, err
		}
		logs = append(logs, l)
	}
	return logs, rows.Err()
}

func (r *JobLogRepository) CountByJobID(jobID int64) (int64, error) {
	var n int64
	err := r.db.QueryRow("SELECT COUNT(*) FROM job_logs WHERE job_id = ?", jobID).Scan(&n)
	return n, err
}

func (r *JobLogRepository) DeleteBefore(before time.Time) (int64, error) {
	res, err := r.db.Exec("DELETE FROM job_logs WHERE timestamp < ?", before)
	if err != nil {
		return 0, err
	}
	return res.RowsAffected()
}

type JobWithStats struct {
	Job
	DurationSeconds *int64 `db:"duration_seconds" json:"duration_seconds"`
	LogLineCount    int64  `db:"log_line_count" json:"log_line_count"`
}

func (r *JobLogRepository) GetAllFiltered(limit, offset int, syncPairID *int64, status, triggerType string, from, to *time.Time) ([]JobWithStats, int64, error) {
	where, args := []string{"1=1"}, []interface{}{}
	if syncPairID != nil {
		where = append(where, "j.sync_pair_id = ?")
		args = append(args, *syncPairID)
	}
	if status != "" {
		where = append(where, "j.status = ?")
		args = append(args, status)
	}
	if triggerType != "" {
		where = append(where, "j.trigger_type = ?")
		args = append(args, triggerType)
	}
	if from != nil {
		where = append(where, "j.created_at >= ?")
		args = append(args, *from)
	}
	if to != nil {
		where = append(where, "j.created_at <= ?")
		args = append(args, *to)
	}
	whereClause := strings.Join(where, " AND ")

	var total int64
	countQuery := "SELECT COUNT(*) FROM jobs j WHERE " + whereClause
	if err := r.db.QueryRow(countQuery, args...).Scan(&total); err != nil {
		return nil, 0, err
	}

	query := `
		SELECT
			j.id, j.sync_pair_id, j.trigger_type, j.status,
			j.started_at, j.finished_at, j.log_file, j.created_at,
			CASE WHEN j.finished_at IS NOT NULL AND j.started_at IS NOT NULL
				THEN (j.finished_at - j.started_at) ELSE NULL END as duration_seconds,
			(SELECT COUNT(*) FROM job_logs WHERE job_id = j.id) as log_line_count
		FROM jobs j
		WHERE ` + whereClause + `
		ORDER BY j.created_at DESC LIMIT ? OFFSET ?`
	args = append(args, limit, offset)

	rows, err := r.db.Query(query, args...)
	if err != nil {
		return nil, 0, err
	}
	defer rows.Close()

	var jobs []JobWithStats
	for rows.Next() {
		var j JobWithStats
		var started, finished sql.NullTime
		var logFile sql.NullString
		var durationSeconds sql.NullInt64
		if err := rows.Scan(&j.ID, &j.SyncPairID, &j.TriggerType, &j.Status,
			&started, &finished, &logFile, &j.CreatedAt,
			&durationSeconds, &j.LogLineCount); err != nil {
			return nil, 0, err
		}
		if started.Valid {
			j.StartedAt = &started.Time
		}
		if finished.Valid {
			j.FinishedAt = &finished.Time
		}
		if logFile.Valid {
			j.LogFile = &logFile.String
		}
		if durationSeconds.Valid {
			j.DurationSeconds = &durationSeconds.Int64
		}
		jobs = append(jobs, j)
	}
	return jobs, total, rows.Err()
}