package main

import (
	"database/sql"
	"embed"
	"encoding/json"
	"fmt"
	"io/fs"
	"sort"
	"strings"
	"time"

	_ "github.com/mattn/go-sqlite3"
)

//go:embed migrations/*.sql
var migrationsFS embed.FS

// DeployTarget represents a deploy configuration stored in operations.db.
type DeployTarget struct {
	App          string            `json:"app"`
	Host         string            `json:"host"` // SSH alias from ~/.ssh/config
	RemoteDir    string            `json:"remote_dir"`
	BinaryName   string            `json:"binary_name"`
	BuildCmd     string            `json:"build_cmd"`
	ServiceUser  string            `json:"service_user"`
	Port         int               `json:"port"`
	HealthPath   string            `json:"health_path"`
	Env          map[string]string `json:"env"`
	Strategy     string            `json:"strategy"`      // "systemd" (default), "systemd-remote", "docker-compose"
	SourceDir    string            `json:"source_dir"`    // override for appDir(); empty = use default apps/<app>
	Branch       string            `json:"branch"`        // git branch for remote deploys; default "main"
	ComposeFiles string            `json:"compose_files"` // comma-separated extra compose files
	CreatedAt    time.Time         `json:"created_at"`
}

// DeployLog records a deploy execution.
type DeployLog struct {
	ID        int64     `json:"id"`
	App       string    `json:"app"`
	Host      string    `json:"host"`
	Status    string    `json:"status"` // "success", "failure"
	Trigger   string    `json:"trigger"` // "manual", "webhook"
	Error     string    `json:"error"`
	Duration  int64     `json:"duration_ms"`
	StartedAt time.Time `json:"started_at"`
}

// Store manages the deploy_server's SQLite database.
type Store struct {
	db *sql.DB
}

func OpenStore(path string) (*Store, error) {
	db, err := sql.Open("sqlite3", path+"?_journal_mode=WAL&_busy_timeout=5000")
	if err != nil {
		return nil, err
	}
	s := &Store{db: db}
	if err := s.migrate(); err != nil {
		db.Close()
		return nil, err
	}
	return s, nil
}

func (s *Store) Close() error {
	return s.db.Close()
}

func (s *Store) migrate() error {
	files, err := fs.Glob(migrationsFS, "migrations/*.sql")
	if err != nil {
		return err
	}
	sort.Strings(files)
	for _, f := range files {
		b, err := migrationsFS.ReadFile(f)
		if err != nil {
			return err
		}
		// Split por sentencia para que cada ALTER pueda fallar idempotentemente
		// sin abortar el resto. SQLite acepta multiples sentencias en Exec(),
		// pero no ignora duplicados — ejecutamos una a una.
		stmts := splitSQLStatements(string(b))
		for _, stmt := range stmts {
			s2 := strings.TrimSpace(stmt)
			if s2 == "" {
				continue
			}
			if _, err := s.db.Exec(s2); err != nil {
				if isIdempotentError(err) {
					continue
				}
				return fmt.Errorf("migrate %s: %w", f, err)
			}
		}
	}
	return nil
}

func splitSQLStatements(s string) []string {
	out := []string{}
	cur := strings.Builder{}
	for _, line := range strings.Split(s, "\n") {
		trim := strings.TrimSpace(line)
		if strings.HasPrefix(trim, "--") || trim == "" {
			continue
		}
		cur.WriteString(line)
		cur.WriteString("\n")
		if strings.HasSuffix(trim, ";") {
			out = append(out, cur.String())
			cur.Reset()
		}
	}
	if cur.Len() > 0 {
		out = append(out, cur.String())
	}
	return out
}

func isIdempotentError(err error) bool {
	msg := err.Error()
	return strings.Contains(msg, "duplicate column") ||
		strings.Contains(msg, "already exists")
}

func (s *Store) AddTarget(t DeployTarget) error {
	envJSON, _ := json.Marshal(t.Env)
	if t.Strategy == "" {
		t.Strategy = "systemd"
	}
	if t.Branch == "" {
		t.Branch = "main"
	}
	_, err := s.db.Exec(`
		INSERT OR REPLACE INTO deploy_targets (app, host, remote_dir, binary_name, build_cmd, service_user, port, health_path, env, strategy, source_dir, branch, compose_files, created_at)
		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
		t.App, t.Host, t.RemoteDir, t.BinaryName, t.BuildCmd, t.ServiceUser, t.Port, t.HealthPath,
		string(envJSON), t.Strategy, t.SourceDir, t.Branch, t.ComposeFiles,
		time.Now().UTC().Format(time.RFC3339))
	return err
}

func (s *Store) RemoveTarget(app string) error {
	res, err := s.db.Exec("DELETE FROM deploy_targets WHERE app = ?", app)
	if err != nil {
		return err
	}
	n, _ := res.RowsAffected()
	if n == 0 {
		return fmt.Errorf("target %q not found", app)
	}
	return nil
}

const selectTargetCols = "app, host, remote_dir, binary_name, build_cmd, service_user, port, health_path, env, strategy, source_dir, branch, compose_files, created_at"

func (s *Store) GetTargets(app string) ([]DeployTarget, error) {
	rows, err := s.db.Query("SELECT "+selectTargetCols+" FROM deploy_targets WHERE app = ?", app)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	return scanTargets(rows)
}

func (s *Store) ListTargets() ([]DeployTarget, error) {
	rows, err := s.db.Query("SELECT "+selectTargetCols+" FROM deploy_targets ORDER BY app, host")
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	return scanTargets(rows)
}

func scanTargets(rows *sql.Rows) ([]DeployTarget, error) {
	var targets []DeployTarget
	for rows.Next() {
		var t DeployTarget
		var envStr, createdStr string
		if err := rows.Scan(&t.App, &t.Host, &t.RemoteDir, &t.BinaryName, &t.BuildCmd, &t.ServiceUser, &t.Port, &t.HealthPath, &envStr, &t.Strategy, &t.SourceDir, &t.Branch, &t.ComposeFiles, &createdStr); err != nil {
			return nil, err
		}
		json.Unmarshal([]byte(envStr), &t.Env)
		t.CreatedAt, _ = time.Parse(time.RFC3339, createdStr)
		targets = append(targets, t)
	}
	return targets, rows.Err()
}

func (s *Store) LogDeploy(l DeployLog) error {
	_, err := s.db.Exec(`
		INSERT INTO deploy_logs (app, host, status, trigger, error, duration_ms, started_at)
		VALUES (?, ?, ?, ?, ?, ?, ?)`,
		l.App, l.Host, l.Status, l.Trigger, l.Error, l.Duration, l.StartedAt.UTC().Format(time.RFC3339))
	return err
}

func (s *Store) RecentLogs(app string, limit int) ([]DeployLog, error) {
	query := "SELECT id, app, host, status, trigger, error, duration_ms, started_at FROM deploy_logs"
	var args []any
	if app != "" {
		query += " WHERE app = ?"
		args = append(args, app)
	}
	query += " ORDER BY started_at DESC LIMIT ?"
	args = append(args, limit)

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

	var logs []DeployLog
	for rows.Next() {
		var l DeployLog
		var startedStr string
		if err := rows.Scan(&l.ID, &l.App, &l.Host, &l.Status, &l.Trigger, &l.Error, &l.Duration, &startedStr); err != nil {
			return nil, err
		}
		l.StartedAt, _ = time.Parse(time.RFC3339, startedStr)
		logs = append(logs, l)
	}
	return logs, rows.Err()
}