package dao

import (
	"context"
	"fmt"
	"time"

	"model-gateway/consts/public"
	"model-gateway/model/entity"

	"gitea.redpowerfuture.com/red-future/common/db/gfdb"
	"github.com/gogf/gf/v2/database/gdb"
	"github.com/gogf/gf/v2/os/gtime"
)

// ======================== 查询辅助 ========================

// taskColumns 查询用的公共字段
const taskColumns = `id, tenant_id, creator, model_name, task_id, biz_name, callback_url, model_key, retry_count, input_ref, request_payload, phase, tmp_file`

// ======================== 事务抢占 ========================

// claimTasks 事务内抢占任务并更新 state=1
func claimTasks(ctx context.Context, where string, args ...any) ([]*entity.AsynchTask, error) {
	var tasks []*entity.AsynchTask
	err := gfdb.DB(ctx).Transaction(ctx, func(ctx context.Context, tx gdb.TX) error {
		sql := fmt.Sprintf(`SELECT %s FROM %s WHERE deleted_at IS NULL AND state = 0 %s LIMIT 1 FOR UPDATE SKIP LOCKED`, taskColumns, public.TableNameTask, where)
		r, err := tx.GetOne(sql, args...)
		if err != nil {
			return err
		}
		if r.IsEmpty() {
			return nil
		}
		var task entity.AsynchTask
		if err := r.Struct(&task); err != nil {
			return err
		}
		now := time.Now()
		_, err = tx.Exec(fmt.Sprintf(`UPDATE %s SET state=1, started_at=?, updated_at=? WHERE id=?`, public.TableNameTask), now, now, task.Id)
		if err != nil {
			return err
		}
		tasks = []*entity.AsynchTask{&task}
		return nil
	})
	return tasks, err
}

// ClaimPendingGlobal 批量抢占 pending 任务
func (d *taskDao) ClaimPendingGlobal(ctx context.Context, batchSize int) ([]*entity.AsynchTask, error) {
	if batchSize <= 0 {
		batchSize = 1
	}
	var tasks []*entity.AsynchTask
	err := gfdb.DB(ctx).Transaction(ctx, func(ctx context.Context, tx gdb.TX) error {
		sql := fmt.Sprintf(`SELECT %s FROM %s WHERE deleted_at IS NULL AND state = 0 ORDER BY enqueue_at ASC LIMIT %d FOR UPDATE SKIP LOCKED`, taskColumns, public.TableNameTask, batchSize)
		r, err := tx.GetAll(sql)
		if err != nil {
			return err
		}
		if r.IsEmpty() {
			return nil
		}
		if err := r.Structs(&tasks); err != nil {
			return err
		}
		now := time.Now()
		for _, t := range tasks {
			_, err = tx.Exec(fmt.Sprintf(`UPDATE %s SET state=1, started_at=?, updated_at=? WHERE id=?`, public.TableNameTask), now, now, t.Id)
			if err != nil {
				return err
			}
		}
		return nil
	})
	return tasks, err
}

// ClaimPendingByTaskIDGlobal 按 task_id 抢占
func (d *taskDao) ClaimPendingByTaskIDGlobal(ctx context.Context, taskID string) (*entity.AsynchTask, error) {
	if taskID == "" {
		return nil, nil
	}
	tasks, err := claimTasks(ctx, "AND task_id = ?", taskID)
	if err != nil || len(tasks) == 0 {
		return nil, err
	}
	return tasks[0], nil
}

// ======================== 更新辅助 ========================

func execSQL(ctx context.Context, sql string, args ...any) error {
	_, err := gfdb.DB(ctx).Exec(ctx, sql, args...)
	return err
}

// updateTask 通用更新
func updateTask(ctx context.Context, id int64, data entity.AsynchTask) error {
	_, err := gfdb.DB(ctx).Model(ctx, public.TableNameTask).OmitEmpty().
		Where(entity.AsynchTaskCol.Id, id).Data(data).Update()
	return err
}

// UpdateSuccessGlobal 更新任务成功
func (d *taskDao) UpdateSuccessGlobal(ctx context.Context, t *entity.AsynchTask) error {
	return updateTask(ctx, t.Id, entity.AsynchTask{
		State:           2,
		OssFile:         t.OssFile,
		FileType:        t.FileType,
		TextResult:      t.TextResult,
		FileSize:        t.FileSize,
		ErrorMsg:        "",
		FinishedAt:      gtime.Now(),
		Phase:           0,
		TmpFile:         "",
		ExpendTokens:    t.ExpendTokens,
		DurationSeconds: t.DurationSeconds,
	})
}

// UpdateFailedGlobal 模型调用失败
func (d *taskDao) UpdateFailedGlobal(ctx context.Context, t *entity.AsynchTask) error {
	return updateTask(ctx, t.Id, entity.AsynchTask{
		State:           3,
		ErrorMsg:        t.ErrorMsg,
		FinishedAt:      gtime.Now(),
		Phase:           0,
		TmpFile:         "",
		TextResult:      t.TextResult,
		DurationSeconds: t.DurationSeconds,
	})
}

// UpdateFailedKeepTmpGlobal OSS 上传失败
func (d *taskDao) UpdateFailedKeepTmpGlobal(ctx context.Context, id int64, errorMsg string) error {
	return execSQL(ctx, fmt.Sprintf(`UPDATE %s SET state=3, error_msg=?, finished_at=?, phase=1, updated_at=? WHERE id=?`, public.TableNameTask), errorMsg, gtime.Now(), gtime.Now(), id)
}

// UpdateTmpAfterModelGlobal 写临时文件
func (d *taskDao) UpdateTmpAfterModelGlobal(ctx context.Context, id int64, tmpFile string) error {
	return execSQL(ctx, fmt.Sprintf(`UPDATE %s SET phase=1, tmp_file=?, updated_at=NOW() WHERE id=?`, public.TableNameTask), tmpFile, id)
}

// RollbackToPendingGlobal 回滚
func (d *taskDao) RollbackToPendingGlobal(ctx context.Context, id int64) error {
	return execSQL(ctx, fmt.Sprintf(`UPDATE %s SET state=0, enqueue_at=NOW(), updated_at=NOW() WHERE id=? AND state=1`, public.TableNameTask), id)
}

// IncRetryCountGlobal 重试计数+1
func (d *taskDao) IncRetryCountGlobal(ctx context.Context, id int64) error {
	return execSQL(ctx, fmt.Sprintf(`UPDATE %s SET retry_count=retry_count+1, updated_at=NOW() WHERE id=?`, public.TableNameTask), id)
}

// RequeueForRetryGlobal 重新入队
func (d *taskDao) RequeueForRetryGlobal(ctx context.Context, id int64, enqueueAt time.Time) error {
	return execSQL(ctx, fmt.Sprintf(`UPDATE %s SET state=0, retry_count=retry_count+1, enqueue_at=?, updated_at=NOW() WHERE id=? AND state=3 AND deleted_at IS NULL`, public.TableNameTask), enqueueAt, id)
}

// ======================== 列表查询 ========================

// ListExpiredDownloadedGlobal
func (d *taskDao) ListExpiredDownloadedGlobal(ctx context.Context, limit int) ([]*entity.AsynchTask, error) {
	return queryTasks(ctx, fmt.Sprintf(`SELECT * FROM %s WHERE deleted_at IS NULL AND state=4 AND expire_at IS NOT NULL AND expire_at < ? LIMIT ?`, public.TableNameTask), gtime.Now(), clampLimit(limit, 200))
}

// ListFailedRetryableGlobal
func (d *taskDao) ListFailedRetryableGlobal(ctx context.Context, limit int) ([]*entity.AsynchTask, error) {
	return queryTasks(ctx, fmt.Sprintf(`SELECT t.*, m.retry_queue_max_seconds FROM %s t JOIN %s m ON t.tenant_id=m.tenant_id AND t.model_name=m.model_name WHERE t.deleted_at IS NULL AND t.state=3 AND t.retry_count < m.retry_times ORDER BY t.updated_at ASC LIMIT ?`, public.TableNameTask, public.TableNameModel), clampLimit(limit, 200))
}

// ListFailedExhaustedGlobal
func (d *taskDao) ListFailedExhaustedGlobal(ctx context.Context, limit int) ([]*entity.AsynchTask, error) {
	return queryTasks(ctx, fmt.Sprintf(`SELECT t.* FROM %s t JOIN %s m ON t.tenant_id=m.tenant_id AND t.model_name=m.model_name WHERE t.deleted_at IS NULL AND t.state=3 AND t.retry_count >= m.retry_times ORDER BY t.updated_at ASC LIMIT ?`, public.TableNameTask, public.TableNameModel), clampLimit(limit, 200))
}

// ListTimeoutTasksGlobal
func (d *taskDao) ListTimeoutTasksGlobal(ctx context.Context, limit int) ([]*entity.AsynchTask, error) {
	return queryTasks(ctx, fmt.Sprintf(`SELECT t.* FROM %s t JOIN %s m ON t.tenant_id=m.tenant_id AND t.model_name=m.model_name WHERE t.deleted_at IS NULL AND t.state IN (0,1) AND m.expected_seconds > 0 AND t.created_at < (NOW() - (m.expected_seconds || ' seconds')::interval) LIMIT ?`, public.TableNameTask, public.TableNameModel), clampLimit(limit, 200))
}

// HardDeleteByIDGlobal
func (d *taskDao) HardDeleteByIDGlobal(ctx context.Context, id int64) error {
	return execSQL(ctx, fmt.Sprintf(`DELETE FROM %s WHERE id=?`, public.TableNameTask), id)
}

// ======================== 内部辅助 ========================

func queryTasks(ctx context.Context, sql string, args ...any) ([]*entity.AsynchTask, error) {
	r, err := gfdb.DB(ctx).GetAll(ctx, sql, args...)
	if err != nil {
		return nil, err
	}
	var list []*entity.AsynchTask
	err = r.Structs(&list)
	return list, err
}

func clampLimit(limit, defaultVal int) int {
	if limit <= 0 {
		return defaultVal
	}
	return limit
}

// UpdateColumns 更新指定字段（结构体版）
func (d *taskDao) UpdateColumns(ctx context.Context, id int64, data entity.AsynchTask) error {
	_, err := gfdb.DB(ctx).Model(ctx, public.TableNameTask).OmitEmpty().
		Where(entity.AsynchTaskCol.Id, id).
		Data(data).
		Update()
	return err
}