package main

import (
	"fmt"
	"os"
	"strings"

	"github.com/spf13/cobra"
	"github.com/steveyegge/beads/internal/beads"
	"github.com/steveyegge/beads/internal/storage/sqlite"
	"github.com/steveyegge/beads/internal/types"
	"github.com/steveyegge/beads/internal/ui"
	"github.com/steveyegge/beads/internal/utils"
)

var molRunCmd = &cobra.Command{
	Use:   "run <proto-id>",
	Short: "Spawn proto and start execution (spawn + assign + pin)",
	Long: `Run a molecule by spawning a proto and setting up for durable execution.

This command:
  1. Spawns the molecule (creates issues from proto template)
  2. Assigns the root issue to the caller
  3. Sets root status to in_progress
  4. Pins the root issue for session recovery

After a crash or session reset, the pinned root issue ensures the agent
can resume from where it left off by checking 'bd ready'.

The --template-db flag enables cross-database spawning: read templates from
one database (e.g., main) while writing spawned instances to another (e.g., wisp).
This is essential for wisp molecule spawning where templates exist in the main
database but instances should be ephemeral.

Example:
  bd mol run mol-version-bump --var version=1.2.0
  bd mol run bd-qqc --var version=0.32.0 --var date=2025-01-01
  bd --db .beads-wisp/beads.db mol run mol-patrol --template-db .beads/beads.db`,
	Args: cobra.ExactArgs(1),
	Run:  runMolRun,
}

func runMolRun(cmd *cobra.Command, args []string) {
	CheckReadonly("mol run")

	ctx := rootCtx

	// mol run requires direct store access
	if store == nil {
		if daemonClient != nil {
			fmt.Fprintf(os.Stderr, "Error: mol run requires direct database access\n")
			fmt.Fprintf(os.Stderr, "Hint: use --no-daemon flag: bd --no-daemon mol run %s ...\n", args[0])
		} else {
			fmt.Fprintf(os.Stderr, "Error: no database connection\n")
		}
		os.Exit(1)
	}

	varFlags, _ := cmd.Flags().GetStringSlice("var")
	templateDB, _ := cmd.Flags().GetString("template-db")

	// Parse variables
	vars := make(map[string]string)
	for _, v := range varFlags {
		parts := strings.SplitN(v, "=", 2)
		if len(parts) != 2 {
			fmt.Fprintf(os.Stderr, "Error: invalid variable format '%s', expected 'key=value'\n", v)
			os.Exit(1)
		}
		vars[parts[0]] = parts[1]
	}

	// Determine which store to use for reading the template
	// If --template-db is set, open a separate connection for reading the template
	// This enables cross-database spawning (read from main, write to wisp)
	//
	// Auto-discovery: if --db contains ".beads-wisp" (wisp storage) but --template-db
	// is not set, automatically use the main database for templates. This handles the
	// common case of spawning patrol molecules from main DB into wisp storage.
	templateStore := store
	if templateDB == "" && strings.Contains(dbPath, ".beads-wisp") {
		// Auto-discover main database for templates
		templateDB = beads.FindDatabasePath()
		if templateDB == "" {
			fmt.Fprintf(os.Stderr, "Error: cannot find main database for templates\n")
			fmt.Fprintf(os.Stderr, "Hint: specify --template-db explicitly\n")
			os.Exit(1)
		}
	}
	if templateDB != "" {
		var err error
		templateStore, err = sqlite.NewWithTimeout(ctx, templateDB, lockTimeout)
		if err != nil {
			fmt.Fprintf(os.Stderr, "Error opening template database %s: %v\n", templateDB, err)
			os.Exit(1)
		}
		defer templateStore.Close()
	}

	// Resolve molecule ID from template store
	moleculeID, err := utils.ResolvePartialID(ctx, templateStore, args[0])
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error resolving molecule ID %s: %v\n", args[0], err)
		os.Exit(1)
	}

	// Load the molecule subgraph from template store
	subgraph, err := loadTemplateSubgraph(ctx, templateStore, moleculeID)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error loading molecule: %v\n", err)
		os.Exit(1)
	}

	// Check for missing variables
	requiredVars := extractAllVariables(subgraph)
	var missingVars []string
	for _, v := range requiredVars {
		if _, ok := vars[v]; !ok {
			missingVars = append(missingVars, v)
		}
	}
	if len(missingVars) > 0 {
		fmt.Fprintf(os.Stderr, "Error: missing required variables: %s\n", strings.Join(missingVars, ", "))
		fmt.Fprintf(os.Stderr, "Provide them with: --var %s=<value>\n", missingVars[0])
		os.Exit(1)
	}

	// Spawn the molecule with actor as assignee (wisp for cleanup - bd-2vh3)
	result, err := spawnMolecule(ctx, store, subgraph, vars, actor, actor, true)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error spawning molecule: %v\n", err)
		os.Exit(1)
	}

	// Update root issue: set status=in_progress and pinned=true
	rootID := result.NewEpicID
	updates := map[string]interface{}{
		"status": string(types.StatusInProgress),
		"pinned": true,
	}
	if err := store.UpdateIssue(ctx, rootID, updates, actor); err != nil {
		fmt.Fprintf(os.Stderr, "Error updating root issue: %v\n", err)
		os.Exit(1)
	}

	// Schedule auto-flush
	markDirtyAndScheduleFlush()

	if jsonOutput {
		outputJSON(map[string]interface{}{
			"root_id":    rootID,
			"created":    result.Created,
			"id_mapping": result.IDMapping,
			"pinned":     true,
			"status":     "in_progress",
			"assignee":   actor,
		})
		return
	}

	fmt.Printf("%s Molecule running: created %d issues\n", ui.RenderPass("✓"), result.Created)
	fmt.Printf("  Root issue: %s (pinned, in_progress)\n", rootID)
	fmt.Printf("  Assignee: %s\n", actor)
	fmt.Println("\nNext steps:")
	fmt.Printf("  bd ready                # Find unblocked work in this molecule\n")
	fmt.Printf("  bd show %s       # View molecule status\n", rootID)
}

func init() {
	molRunCmd.Flags().StringSlice("var", []string{}, "Variable substitution (key=value)")
	molRunCmd.Flags().String("template-db", "", "Database to read templates from (enables cross-database spawning)")

	molCmd.AddCommand(molRunCmd)
}