package platform

import (
	"context"
	"database/sql"
	"encoding/json"
)

func (s *service) canvasRunResults(ctx context.Context, run canvasQueueRun) (map[string]canvasStepResult, error) {
	rows, err := s.db.QueryContext(ctx, `SELECT id,status,output FROM canvas_ai_steps WHERE project=$1 AND workspace_id=$2 AND run_id=$3 ORDER BY ordinal`, run.Project, run.Workspace, run.ID)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	results := map[string]canvasStepResult{}
	for rows.Next() {
		var id, status string
		var raw []byte
		if err = rows.Scan(&id, &status, &raw); err != nil {
			return nil, err
		}
		if status == "queued" {
			continue
		}
		if status == "running" {
			return nil, sql.ErrNoRows
		}
		var output struct {
			Text    string `json:"text"`
			AssetID string `json:"assetId"`
		}
		if len(raw) > 0 {
			if err = json.Unmarshal(raw, &output); err != nil {
				return nil, err
			}
		}
		results[id] = canvasStepResult{Status: status, Text: output.Text, AssetID: output.AssetID}
	}
	return results, rows.Err()
}

// A 429 codex_busy response proves the worker did not invoke the CLI. Only this
// admission failure can return a step to the persistent queue for safe retry.
func (s *service) requeueCanvasStep(ctx context.Context, run canvasQueueRun, step canvasAIStepPlan) (bool, error) {
	tx, err := s.db.BeginTx(ctx, nil)
	if err != nil {
		return false, err
	}
	defer tx.Rollback()
	var locked string
	err = tx.QueryRowContext(ctx, `SELECT id::text FROM workspaces WHERE project=$1 AND id=$2 FOR UPDATE`, run.Project, run.Workspace).Scan(&locked)
	if err != nil {
		return false, err
	}
	var active bool
	err = tx.QueryRowContext(ctx, `SELECT status='running' AND lease_id=$4 AND NOT cancel_requested FROM canvas_ai_runs WHERE project=$1 AND workspace_id=$2 AND id=$3 FOR UPDATE`, run.Project, run.Workspace, run.ID, run.Lease).Scan(&active)
	if err != nil {
		return false, err
	}
	if !active {
		return false, nil
	}
	result, err := tx.ExecContext(ctx, `UPDATE canvas_ai_steps SET status='queued',started_at=NULL,error_code=NULL WHERE project=$1 AND workspace_id=$2 AND run_id=$3 AND id=$4 AND status='running'`, run.Project, run.Workspace, run.ID, step.ID)
	if err != nil {
		return false, err
	}
	count, _ := result.RowsAffected()
	if count == 0 {
		return false, nil
	}
	_, err = tx.ExecContext(ctx, `UPDATE canvas_ai_runs SET status='queued',available_at=now()+interval '5 seconds',lease_id=NULL,lease_until=NULL WHERE project=$1 AND workspace_id=$2 AND id=$3`, run.Project, run.Workspace, run.ID)
	if err != nil {
		return false, err
	}
	if err = appendAIEvent(ctx, tx, run.Project, run.Workspace, run.ID, "step.queued", response{"step_id": step.ID, "board_id": step.BoardID, "node_id": step.NodeID, "reason": "worker_busy"}); err != nil {
		return false, err
	}
	for _, edge := range run.Plan.Edges {
		if edge.Target == step.ID {
			if err = appendAIEvent(ctx, tx, run.Project, run.Workspace, run.ID, "edge.skipped", response{"logical_edge_id": edge.ID, "status": "skipped", "reason": "worker_busy"}); err != nil {
				return false, err
			}
		}
	}
	if err = appendAIEvent(ctx, tx, run.Project, run.Workspace, run.ID, "run.queued", response{"status": "queued", "reason": "worker_busy"}); err != nil {
		return false, err
	}
	if err = tx.Commit(); err != nil {
		return false, err
	}
	return true, nil
}