import { db } from '../db'
import { jsonResponse, errorResponse } from '../utils/cors'

function parseCanvas(row: any) {
  return {
    ...row,
    is_default: !!row.is_default,
    is_system: !!row.is_system,
    show_in_toolbar: !!row.show_in_toolbar,
    config: row.config ? JSON.parse(row.config) : null,
    tools: row.tools ? JSON.parse(row.tools) : []
  }
}

export function handleToolbarCanvas() {
  const rows = db.query('SELECT * FROM project_canvas WHERE show_in_toolbar = 1 ORDER BY toolbar_order ASC, name ASC').all()
  return jsonResponse((rows as any[]).map(parseCanvas))
}

export function handleDefaultCanvas() {
  const row = db.query('SELECT * FROM project_canvas WHERE is_default = 1 LIMIT 1').get() as any
  if (!row) {
    return jsonResponse({ hasDefault: false })
  }
  return jsonResponse({ hasDefault: true, canvas: parseCanvas(row) })
}

export async function handleCanvas(req: Request) {
  if (req.method === 'GET') {
    const rows = db.query('SELECT * FROM project_canvas ORDER BY is_system DESC, is_default DESC, name ASC').all()
    return jsonResponse((rows as any[]).map(parseCanvas))
  }

  if (req.method === 'POST') {
    const body = await req.json()
    const id = body.id || `canvas-${Date.now()}`
    const stmt = db.prepare(`
      INSERT OR REPLACE INTO project_canvas
      (id, name, description, type, theme_id, config, tools, is_default, is_system, show_in_toolbar, toolbar_icon, toolbar_order, updated_at)
      VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP)
    `)
    stmt.run(
      id,
      body.name,
      body.description || '',
      body.type || 'project',
      body.theme_id || null,
      JSON.stringify(body.config || {}),
      JSON.stringify(body.tools || []),
      body.is_default ? 1 : 0,
      body.is_system ? 1 : 0,
      body.show_in_toolbar ? 1 : 0,
      body.toolbar_icon || null,
      body.toolbar_order ?? 99
    )
    return jsonResponse({ success: true, id })
  }

  return null
}

export async function handleCanvasById(req: Request, id: string, action?: string) {
  // POST /api/canvas/:id/clone
  if (action === 'clone' && req.method === 'POST') {
    const original = db.query('SELECT * FROM project_canvas WHERE id = ?').get(id) as any
    if (!original) {
      return errorResponse('Canvas not found', 404)
    }

    const body = await req.json()
    const newId = `canvas-${Date.now()}`
    const newName = body.name || `${original.name} (copia)`

    const stmt = db.prepare(`
      INSERT INTO project_canvas
      (id, name, description, type, theme_id, config, tools, is_default, is_system)
      VALUES (?, ?, ?, 'project', ?, ?, ?, 0, 0)
    `)
    stmt.run(newId, newName, original.description, original.theme_id, original.config, original.tools)

    // Clone canvas components
    const components = db.query('SELECT * FROM canvas_components WHERE canvas_id = ?').all(id) as any[]
    if (components.length > 0) {
      const compStmt = db.prepare(`
        INSERT INTO canvas_components (canvas_id, component_id, position, props, layout, is_visible)
        VALUES (?, ?, ?, ?, ?, ?)
      `)
      for (const comp of components) {
        compStmt.run(newId, comp.component_id, comp.position, comp.props, comp.layout, comp.is_visible)
      }
    }

    return jsonResponse({ success: true, id: newId })
  }

  // GET /api/canvas/:id
  if (req.method === 'GET' && !action) {
    const row = db.query('SELECT * FROM project_canvas WHERE id = ?').get(id) as any
    if (!row) {
      return errorResponse('Canvas not found', 404)
    }
    return jsonResponse(parseCanvas(row))
  }

  // PUT /api/canvas/:id
  if (req.method === 'PUT' && !action) {
    const canvas = db.query('SELECT * FROM project_canvas WHERE id = ?').get(id) as any
    if (!canvas) {
      return errorResponse('Canvas not found', 404)
    }

    const body = await req.json()
    const updates: string[] = []
    const values: any[] = []

    // System canvas can only modify toolbar settings and is_default
    if (canvas.is_system) {
      if (body.is_default !== undefined) { updates.push('is_default = ?'); values.push(body.is_default ? 1 : 0) }
      if (body.show_in_toolbar !== undefined) { updates.push('show_in_toolbar = ?'); values.push(body.show_in_toolbar ? 1 : 0) }
      if (body.toolbar_icon !== undefined) { updates.push('toolbar_icon = ?'); values.push(body.toolbar_icon) }
      if (body.toolbar_order !== undefined) { updates.push('toolbar_order = ?'); values.push(body.toolbar_order) }
    } else {
      if (body.name !== undefined) { updates.push('name = ?'); values.push(body.name) }
      if (body.description !== undefined) { updates.push('description = ?'); values.push(body.description) }
      if (body.theme_id !== undefined) { updates.push('theme_id = ?'); values.push(body.theme_id) }
      if (body.config !== undefined) { updates.push('config = ?'); values.push(JSON.stringify(body.config)) }
      if (body.tools !== undefined) { updates.push('tools = ?'); values.push(JSON.stringify(body.tools)) }
      if (body.is_default !== undefined) { updates.push('is_default = ?'); values.push(body.is_default ? 1 : 0) }
      if (body.show_in_toolbar !== undefined) { updates.push('show_in_toolbar = ?'); values.push(body.show_in_toolbar ? 1 : 0) }
      if (body.toolbar_icon !== undefined) { updates.push('toolbar_icon = ?'); values.push(body.toolbar_icon) }
      if (body.toolbar_order !== undefined) { updates.push('toolbar_order = ?'); values.push(body.toolbar_order) }
    }

    if (updates.length > 0) {
      updates.push('updated_at = CURRENT_TIMESTAMP')
      values.push(id)
      const sql = `UPDATE project_canvas SET ${updates.join(', ')} WHERE id = ?`
      db.run(sql, values)
    }

    return jsonResponse({ success: true, id })
  }

  // DELETE /api/canvas/:id
  if (req.method === 'DELETE' && !action) {
    const canvas = db.query('SELECT is_system FROM project_canvas WHERE id = ?').get(id) as { is_system: number } | null
    if (canvas?.is_system) {
      return errorResponse('Cannot delete system canvas', 403)
    }
    db.run('DELETE FROM project_canvas WHERE id = ?', [id])
    return jsonResponse({ success: true })
  }

  return null
}

// Canvas Components API
export async function handleCanvasComponents(req: Request, canvasId: string) {
  if (req.method === 'GET') {
    const rows = db.query(`
      SELECT cc.*, vc.name, vc.template, vc.setup, vc.style, vc.props as component_props, vc.imports
      FROM canvas_components cc
      JOIN vue_components vc ON cc.component_id = vc.id
      WHERE cc.canvas_id = ?
      ORDER BY cc.position ASC
    `).all(canvasId) as any[]

    const components = rows.map(row => ({
      id: row.id,
      canvasId: row.canvas_id,
      componentId: row.component_id,
      position: row.position,
      props: row.props ? JSON.parse(row.props) : {},
      layout: row.layout ? JSON.parse(row.layout) : null,
      isVisible: !!row.is_visible,
      createdAt: row.created_at,
      component: {
        id: row.component_id,
        name: row.name,
        template: row.template,
        setup: row.setup,
        style: row.style,
        props: row.component_props ? JSON.parse(row.component_props) : [],
        imports: row.imports ? JSON.parse(row.imports) : []
      }
    }))

    return jsonResponse(components)
  }

  if (req.method === 'POST') {
    const body = await req.json()

    // Verify component exists
    const component = db.query('SELECT id FROM vue_components WHERE id = ?').get(body.component_id)
    if (!component) {
      return errorResponse('Component not found', 404)
    }

    // Get next position
    const maxPos = db.query('SELECT MAX(position) as max FROM canvas_components WHERE canvas_id = ?').get(canvasId) as { max: number | null }
    const position = body.position ?? ((maxPos?.max ?? -1) + 1)

    const stmt = db.prepare(`
      INSERT OR REPLACE INTO canvas_components
      (canvas_id, component_id, position, props, layout, is_visible)
      VALUES (?, ?, ?, ?, ?, ?)
    `)
    stmt.run(
      canvasId,
      body.component_id,
      position,
      JSON.stringify(body.props || {}),
      body.layout ? JSON.stringify(body.layout) : null,
      body.is_visible !== false ? 1 : 0
    )

    return jsonResponse({ success: true })
  }

  return null
}

export async function handleCanvasComponentById(req: Request, canvasId: string, componentId: string) {
  if (req.method === 'PUT') {
    const body = await req.json()
    const updates: string[] = []
    const values: any[] = []

    if (body.position !== undefined) { updates.push('position = ?'); values.push(body.position) }
    if (body.props !== undefined) { updates.push('props = ?'); values.push(JSON.stringify(body.props)) }
    if (body.layout !== undefined) { updates.push('layout = ?'); values.push(JSON.stringify(body.layout)) }
    if (body.is_visible !== undefined) { updates.push('is_visible = ?'); values.push(body.is_visible ? 1 : 0) }

    if (updates.length > 0) {
      values.push(canvasId, componentId)
      const sql = `UPDATE canvas_components SET ${updates.join(', ')} WHERE canvas_id = ? AND component_id = ?`
      db.run(sql, values)
    }

    return jsonResponse({ success: true })
  }

  if (req.method === 'DELETE') {
    db.run('DELETE FROM canvas_components WHERE canvas_id = ? AND component_id = ?', [canvasId, componentId])
    return jsonResponse({ success: true })
  }

  return null
}