package workspaceprovision

import (
	"context"
	"database/sql"
	"errors"
	"fmt"
	"os"
	"path/filepath"
	"strings"

	"inbox/internal/app/workspaceruntime"
	"inbox/internal/base/slug"
	"inbox/internal/domain/workspace"
)

type store interface {
	GetProject(context.Context, string) (workspace.Project, error)
	GetProjectByRootPath(context.Context, string) (workspace.Project, error)
	GetProjectBySlug(context.Context, string) (workspace.Project, error)
	CreateProject(context.Context, workspace.Project) (workspace.Project, error)
	UpdateProjectDefaultBranch(context.Context, string, string) error
	GetWorkspace(context.Context, string) (workspace.Workspace, error)
	GetWorkspaceByProjectAndSlug(context.Context, string, string) (workspace.Workspace, error)
	CreateWorkspace(context.Context, workspace.Workspace) (workspace.Workspace, error)
	UpdateWorkspace(context.Context, workspace.Workspace) error
}

type Service struct {
	store         store
	workspacesDir string
	runtime       runtimeManager
}

type ProvisionRequest struct {
	ProjectDir string
	Name       string
}

type runtimeManager interface {
	EnsureRepository(ctx context.Context, projectDir string) (string, error)
	Ensure(ctx context.Context, workspaceID string) (workspace.Workspace, workspaceruntime.Runtime, error)
}

func NewService(store store, workspacesDir string, runtime runtimeManager) *Service {
	return &Service{
		store:         store,
		workspacesDir: strings.TrimSpace(workspacesDir),
		runtime:       runtime,
	}
}

func (s *Service) Provision(ctx context.Context, req ProvisionRequest) (workspace.Workspace, workspaceruntime.Runtime, error) {
	if s.runtime == nil {
		return workspace.Workspace{}, workspaceruntime.Runtime{}, fmt.Errorf("workspace runtime is not configured")
	}
	projectDir, err := filepath.Abs(strings.TrimSpace(req.ProjectDir))
	if err != nil {
		return workspace.Workspace{}, workspaceruntime.Runtime{}, fmt.Errorf("resolve project dir: %w", err)
	}
	info, err := os.Stat(projectDir)
	if err != nil {
		return workspace.Workspace{}, workspaceruntime.Runtime{}, fmt.Errorf("stat project dir: %w", err)
	}
	if !info.IsDir() {
		return workspace.Workspace{}, workspaceruntime.Runtime{}, fmt.Errorf("project dir is not a directory: %s", projectDir)
	}

	projectName := filepath.Base(projectDir)
	projectSlug := slug.Normalize(projectName)
	if projectSlug == "" {
		projectSlug = "project"
	}
	workspaceSlug := slug.Normalize(firstNonEmpty(req.Name, projectName))
	if workspaceSlug == "" {
		workspaceSlug = projectSlug
	}

	baseBranch, err := s.runtime.EnsureRepository(ctx, projectDir)
	if err != nil {
		return workspace.Workspace{}, workspaceruntime.Runtime{}, err
	}

	project, err := s.ensureProject(ctx, projectDir, projectName, projectSlug, baseBranch)
	if err != nil {
		return workspace.Workspace{}, workspaceruntime.Runtime{}, err
	}

	ws, err := s.store.GetWorkspaceByProjectAndSlug(ctx, project.ID, workspaceSlug)
	if err != nil {
		if !errors.Is(err, sql.ErrNoRows) {
			return workspace.Workspace{}, workspaceruntime.Runtime{}, err
		}
		ws = workspace.NormalizeWorkspaceForCreate(workspace.Workspace{
			ProjectID:  project.ID,
			Slug:       workspaceSlug,
			Name:       workspaceSlug,
			RootPath:   filepath.Join(s.workspacesDir, workspaceSlug),
			BaseBranch: baseBranch,
		})
		ws, err = s.store.CreateWorkspace(ctx, ws)
		if err != nil {
			return workspace.Workspace{}, workspaceruntime.Runtime{}, err
		}
	}

	ws = workspace.ApplyManagedRuntimeConfig(ws, s.workspacesDir, baseBranch)
	if err := s.store.UpdateWorkspace(ctx, ws); err != nil {
		return workspace.Workspace{}, workspaceruntime.Runtime{}, err
	}
	return s.runtime.Ensure(ctx, ws.ID)
}

func (s *Service) ensureProject(ctx context.Context, projectDir, projectName, projectSlug, baseBranch string) (workspace.Project, error) {
	project, err := s.store.GetProjectByRootPath(ctx, projectDir)
	if err != nil {
		if !errors.Is(err, sql.ErrNoRows) {
			return workspace.Project{}, err
		}
		project = workspace.NormalizeProjectForCreate(workspace.Project{
			Slug:          projectSlug,
			Name:          projectName,
			RootPath:      projectDir,
			DefaultBranch: baseBranch,
		})
		created, createErr := s.store.CreateProject(ctx, project)
		if createErr == nil {
			return created, nil
		}
		if existing, lookupErr := s.store.GetProjectBySlug(ctx, projectSlug); lookupErr == nil && existing.RootPath == projectDir {
			project = existing
		} else {
			return workspace.Project{}, createErr
		}
	}
	if project.DefaultBranch != baseBranch {
		if err := s.store.UpdateProjectDefaultBranch(ctx, project.ID, baseBranch); err != nil {
			return workspace.Project{}, err
		}
		project.DefaultBranch = baseBranch
	}
	return project, nil
}

func firstNonEmpty(values ...string) string {
	for _, value := range values {
		if strings.TrimSpace(value) != "" {
			return value
		}
	}
	return ""
}