import type { RouteLocationNormalized } from 'vue-router'
import { useProjectsStore } from '@/stores/projects'
import { episodeService } from '@/services/episode'
import { shotService } from '@/services/shot'

export interface BreadcrumbItem {
  label: string
  href?: string
  isActive?: boolean
  /** True for the crumb representing the current project tab (Overview/Shots/Assets/...), so the header can render a tab-switcher dropdown on it. */
  isTabCrumb?: boolean
  /** True for the crumb representing the current project name, so the header can render a project-switcher dropdown on it. */
  isProjectCrumb?: boolean
}

export class BreadcrumbService {
  static async generateBreadcrumbs(route: RouteLocationNormalized): Promise<BreadcrumbItem[]> {
    const pathSegments = route.path.split('/').filter(Boolean)
    const crumbs: BreadcrumbItem[] = [{ label: 'Home', href: '/' }]
    
    // Handle different route patterns
    if (pathSegments[0] === 'projects' && pathSegments[1]) {
      const projectId = parseInt(pathSegments[1])
      
      if (!isNaN(projectId)) {
        // Get project information - initialize store here when needed
        const projectsStore = useProjectsStore()
        let project = projectsStore.getProjectById(projectId)
        if (!project) {
          try {
            project = await projectsStore.getProject(projectId)
          } catch (error) {
            console.error('Failed to load project for breadcrumbs:', error)
          }
        }

        // Add project breadcrumb
        crumbs.push({
          label: project ? project.name : `Project ${projectId}`,
          href: `/projects/${projectId}`,
          isProjectCrumb: true
        })

        // Handle tab-based navigation
        const tab = route.meta?.tab as string
        const tabLabel = route.meta?.tabLabel as string || this.getTabLabel(tab)
        
        if (tab) {
          // For shots tab with episode context
          if (tab === 'shots' && route.params.episodeId) {
            crumbs.push({
              label: tabLabel,
              href: `/projects/${projectId}/shots`,
              isTabCrumb: true
            })
            
            // Add episode context
            const episodeId = parseInt(route.params.episodeId as string)
            if (!isNaN(episodeId)) {
              try {
                const episodes = await episodeService.getProjectEpisodes(projectId)
                const episode = episodes.find(ep => ep.id === episodeId)
                crumbs.push({
                  label: episode ? episode.name : `Episode ${episodeId}`,
                  isActive: true
                })
              } catch (error) {
                console.error('Failed to load episode for breadcrumbs:', error)
                crumbs.push({
                  label: `Episode ${episodeId}`,
                  isActive: true
                })
              }
            }
          } else {
            // Regular tab navigation (Overview included, so the trail always reads Home > Project > Tab)
            crumbs.push({
              label: tabLabel,
              isActive: true,
              isTabCrumb: true
            })
          }
        }
        
        // Handle shot detail page (path: /projects/:projectId/shots/:shotId)
        if (pathSegments[2] === 'shots' && pathSegments[3]) {
          const shotId = parseInt(pathSegments[3])
          if (!isNaN(shotId)) {
            try {
              const shot = await shotService.getShot(shotId)
              // Replace the last item (Shots) with Shots > ShotName
              if (crumbs.length > 1) {
                crumbs[crumbs.length - 1] = {
                  label: 'Shots',
                  href: `/projects/${projectId}/shots`,
                  isTabCrumb: true
                }
              }
              crumbs.push({
                label: shot.name,
                isActive: true
              })
            } catch (error) {
              console.error('Failed to load shot for breadcrumbs:', error)
              // Keep the default behavior - show shot ID
            }
          }
        }
      }
    } else {
      // Handle other routes
      let currentPath = ''
      pathSegments.forEach((segment, index) => {
        currentPath += `/${segment}`
        const isLast = index === pathSegments.length - 1
        
        // Format segment label
        const label = this.formatSegmentLabel(segment)
        
        crumbs.push({
          label,
          href: isLast ? undefined : currentPath,
          isActive: isLast
        })
      })
    }
    
    return crumbs
  }

  private static getTabLabel(tab: string): string {
    switch (tab) {
      case 'overview': return 'Overview'
      case 'shots': return 'Shots'
      case 'assets': return 'Assets'
      case 'technical-specs': return 'Technical Specs'
      default: return tab.charAt(0).toUpperCase() + tab.slice(1).replace(/-/g, ' ')
    }
  }

  private static formatSegmentLabel(segment: string): string {
    // Handle special cases
    if (segment === 'api-keys') return 'API Keys'
    if (segment === 'technical-specs') return 'Technical Specs'
    
    // Default formatting
    return segment.charAt(0).toUpperCase() + segment.slice(1).replace(/-/g, ' ')
  }
}