import { z } from 'zod'
import type { Prisma } from '@prisma/client'
import { router, protectedProcedure, adminProcedure } from '../trpc'
import { logAudit } from '../utils/audit'
import { wizardConfigSchema } from '@/types/wizard-config'
import { parseWizardConfig } from '@/lib/wizard-config'

export const programRouter = router({
  /**
   * List all programs with optional filtering.
   * When includeStages is true, returns stages nested under
   * pipelines -> tracks -> stages, flattened as `stages` for convenience.
   */
  list: protectedProcedure
    .input(
      z.object({
        status: z.enum(['DRAFT', 'ACTIVE', 'ARCHIVED']).optional(),
        includeStages: z.boolean().optional(),
      }).optional()
    )
    .query(async ({ ctx, input }) => {
      const includeStages = input?.includeStages || false

      const programs = await ctx.prisma.program.findMany({
        where: input?.status ? { status: input.status } : undefined,
        orderBy: { year: 'desc' },
        include: includeStages
          ? {
              pipelines: {
                include: {
                  tracks: {
                    include: {
                      stages: {
                        orderBy: { sortOrder: 'asc' },
                        include: {
                          _count: {
                            select: { assignments: true, projectStageStates: true },
                          },
                        },
                      },
                    },
                  },
                },
              },
            }
          : undefined,
      })

      // Flatten stages into a rounds-compatible shape for backward compatibility
      return programs.map((p) => ({
        ...p,
        // Provide a flat `stages` array for convenience
        stages: (p as any).pipelines?.flatMap((pipeline: any) =>
          pipeline.tracks?.flatMap((track: any) =>
            (track.stages || []).map((stage: any) => ({
              ...stage,
              pipelineName: pipeline.name,
              trackName: track.name,
              // Backward-compatible _count shape
              _count: {
                projects: stage._count?.projectStageStates || 0,
                assignments: stage._count?.assignments || 0,
              },
            }))
          ) || []
        ) || [],
        // Legacy alias
        rounds: (p as any).pipelines?.flatMap((pipeline: any) =>
          pipeline.tracks?.flatMap((track: any) =>
            (track.stages || []).map((stage: any) => ({
              id: stage.id,
              name: stage.name,
              status: stage.status === 'STAGE_ACTIVE' ? 'ACTIVE'
                : stage.status === 'STAGE_CLOSED' ? 'CLOSED'
                : stage.status,
              votingEndAt: stage.windowCloseAt,
              _count: {
                projects: stage._count?.projectStageStates || 0,
                assignments: stage._count?.assignments || 0,
              },
            }))
          ) || []
        ) || [],
      }))
    }),

  /**
   * Get a single program with its stages (via pipelines)
   */
  get: protectedProcedure
    .input(z.object({ id: z.string() }))
    .query(async ({ ctx, input }) => {
      const program = await ctx.prisma.program.findUniqueOrThrow({
        where: { id: input.id },
        include: {
          pipelines: {
            include: {
              tracks: {
                include: {
                  stages: {
                    orderBy: { sortOrder: 'asc' },
                    include: {
                      _count: {
                        select: { assignments: true, projectStageStates: true },
                      },
                    },
                  },
                },
              },
            },
          },
        },
      })

      // Flatten stages for convenience
      const stages = (program as any).pipelines?.flatMap((pipeline: any) =>
        pipeline.tracks?.flatMap((track: any) =>
          (track.stages || []).map((stage: any) => ({
            ...stage,
            _count: {
              projects: stage._count?.projectStageStates || 0,
              assignments: stage._count?.assignments || 0,
            },
          }))
        ) || []
      ) || []

      return {
        ...program,
        stages,
        // Legacy alias
        rounds: stages.map((s: any) => ({
          id: s.id,
          name: s.name,
          status: s.status === 'STAGE_ACTIVE' ? 'ACTIVE'
            : s.status === 'STAGE_CLOSED' ? 'CLOSED'
            : s.status,
          votingEndAt: s.windowCloseAt,
          _count: s._count,
        })),
      }
    }),

  /**
   * Create a new program (admin only)
   */
  create: adminProcedure
    .input(
      z.object({
        name: z.string().min(1).max(255),
        year: z.number().int().min(2020).max(2100),
        description: z.string().optional(),
      })
    )
    .mutation(async ({ ctx, input }) => {
      const program = await ctx.prisma.program.create({
        data: input,
      })

      // Audit log
      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'CREATE',
        entityType: 'Program',
        entityId: program.id,
        detailsJson: input,
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      return program
    }),

  /**
   * Update a program (admin only)
   */
  update: adminProcedure
    .input(
      z.object({
        id: z.string(),
        name: z.string().min(1).max(255).optional(),
        slug: z.string().min(1).max(100).optional(),
        status: z.enum(['DRAFT', 'ACTIVE', 'ARCHIVED']).optional(),
        description: z.string().optional(),
        settingsJson: z.record(z.any()).optional(),
      })
    )
    .mutation(async ({ ctx, input }) => {
      const { id, ...data } = input

      const program = await ctx.prisma.program.update({
        where: { id },
        data,
      })

      // Audit log
      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'UPDATE',
        entityType: 'Program',
        entityId: id,
        detailsJson: data,
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      return program
    }),

  /**
   * Delete a program (admin only)
   * Note: This will cascade delete all rounds, projects, etc.
   */
  delete: adminProcedure
    .input(z.object({ id: z.string() }))
    .mutation(async ({ ctx, input }) => {
      const program = await ctx.prisma.program.delete({
        where: { id: input.id },
      })

      // Audit log
      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'DELETE',
        entityType: 'Program',
        entityId: input.id,
        detailsJson: { name: program.name, year: program.year },
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      return program
    }),

  /**
   * Get wizard config for a program (parsed from settingsJson)
   */
  getWizardConfig: protectedProcedure
    .input(z.object({ programId: z.string() }))
    .query(async ({ ctx, input }) => {
      const program = await ctx.prisma.program.findUniqueOrThrow({
        where: { id: input.programId },
        select: { settingsJson: true },
      })
      return parseWizardConfig(program.settingsJson)
    }),

  /**
   * Update wizard config for a program (admin only)
   */
  updateWizardConfig: adminProcedure
    .input(
      z.object({
        programId: z.string(),
        wizardConfig: wizardConfigSchema,
      })
    )
    .mutation(async ({ ctx, input }) => {
      const program = await ctx.prisma.program.findUniqueOrThrow({
        where: { id: input.programId },
        select: { settingsJson: true },
      })

      const currentSettings = (program.settingsJson || {}) as Record<string, unknown>

      const updatedSettings = {
        ...currentSettings,
        wizardConfig: input.wizardConfig,
      }

      await ctx.prisma.program.update({
        where: { id: input.programId },
        data: {
          settingsJson: updatedSettings as Prisma.InputJsonValue,
        },
      })

      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'UPDATE',
        entityType: 'Program',
        entityId: input.programId,
        detailsJson: {
          field: 'wizardConfig',
          stepsEnabled: input.wizardConfig.steps.filter((s) => s.enabled).length,
          totalSteps: input.wizardConfig.steps.length,
          customFieldsCount: input.wizardConfig.customFields?.length ?? 0,
        },
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      return { success: true }
    }),
})