library(rlang)
library(formula.tools)

## all tests are wrapped in a single function to make it easier to call on different designs,
## which is done at the end of this script

comprehensive_design_test  <- function(nosim, resps, destype, designpath, ul, bcoeff,  decisiongroups=c(0,1)) {
    # Test cases related to sim_all function
  test_that("u is not a list of lists", {
    expect_error(sim_all(nosim = nosim, resps=resps, destype = destype,
                         designpath = designpath, u=data.frame(u=" alp"), bcoeff = bcoeff),
                 "must be provided and must be a list containing at least one list")
  })

  test_that("no value provided for  utility", {
    expect_error(sim_all(nosim = nosim, resps=resps, destype = destype,
                         designpath = designpath, bcoeff = bcoeff),
                 "must be provided and must be a list containing at least one list")
  })


  test_that("wrong designtype", {
    expect_error(sim_all(nosim = nosim, resps=resps, destype = "ng",
                         designpath = designpath, u=ul, bcoeff = bcoeff, decisiongroups = decisiongroups),"Invalid value for design. Please provide either 'ngene' or 'spdesign'.")
  })


  test_that("folder does not exist", {
    expect_error(sim_all(nosim = nosim, resps=resps, destype = destype,
                         designpath = system.file("da/bullshit", package = "simulateDCE"), u=ul, bcoeff = bcoeff, decisiongroups = decisiongroups)
      ,
                 "The folder where your designs are stored does not exist.")
  })

  test_that("seed setting makes code reproducible", {
    set.seed(3333)
    result1 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff, decisiongroups = decisiongroups)

    set.seed(3333)
    result2 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff, decisiongroups = decisiongroups)

    expect_identical(result1[["summaryall"]], result2[["summaryall"]])
  })

  test_that("No seed setting makes code results different", {

    result1 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff, decisiongroups = decisiongroups)


    result2 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff, decisiongroups = decisiongroups)

    expect_failure(expect_identical(result1[["summaryall"]], result2[["summaryall"]]))
  })

  test_that("Length of utility functions matches number of decision groups", {
    # Define test inputs
    badbcoeff = list(
      basc = 0.2,
      bcow = 0.3,
      badv = 0.3,
      bvet = 0.3,
      bfar = 0.3,
      bmet = 0.3,
      bbon = 0.3,
      bbon2 = 1.9,
      basc2 =2)

    badlist <- list(u1= list(
      v1 =V.1 ~  bcow*alt1.cow + badv * alt1.adv + bvet * alt1.vet + bfar * alt1.far + bmet*alt1.met + bbon * alt1.bon,
      v2 =V.2 ~  bcow*alt2.cow + badv * alt2.adv + bvet * alt2.vet + bfar * alt2.far + bmet*alt2.met + bbon * alt2.bon,
      v3 =V.3 ~ basc)
      ,
      u2 = list(
        v1 =V.1 ~  bcow*alt1.cow + badv * alt1.adv + bvet * alt1.vet + bfar * alt1.far + bbon * alt1.bon,
        v2 =V.2 ~  bcow*alt2.cow + badv * alt2.adv + bvet * alt2.vet + bfar * alt2.far + bbon * alt2.bon,
        v3 =V.3 ~ basc),
      u3 = list(
        v1 =V.1 ~  bbon2 * alt1.bon,
        v2 =V.2 ~  bbon2 * alt2.bon,
        v3 =V.3 ~ basc),

      u4 = list(v1 =V.1 ~ basc2 + bcow*alt1.cow + badv * alt1.adv + bvet * alt1.vet + bfar * alt1.far + bmet*alt1.met + bbon * alt1.bon,
                v2 =V.2 ~  bcow*alt2.cow + badv * alt2.adv + bvet * alt2.vet + bfar * alt2.far + bmet*alt2.met + bbon * alt2.bon,
                v3 =V.3 ~ basc)
    )
    baddecisiongroups <- c(0,0.3,0.6,1)

    # Test that the function throws an error when lengths don't match
    expect_error(sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = badlist, bcoeff = badbcoeff, decisiongroups =  baddecisiongroups), "Number of decision groups must equal number of utility functions!")

    # Define test inputs where lengths match
    gooddecisiongroups <- c(0,0.3,0.6, 0.8, 1)

    # Test that the function does not throw an error when lengths match (assumed true in input)
    expect_no_error(sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff, decisiongroups =  decisiongroups))
  })


  ########### Additional Tests ##############
  test_that("bcoeff is provided", {
      expect_error(sim_all(nosim = nosim, resps = resps, destype = destype,
                           designpath = designpath, u = ul))
  })

  test_that("bcoeff contains valid values", {
    expect_error(sim_all(nosim = nosim, resps = resps, destype = destype,
                         designpath = designpath, u = ul, bcoeff = list(bsq = "invalid")))
  })

  test_that("bcoeff is a list", {
    expect_error(sim_all(nosim = nosim, resps = resps, destype = destype,
                         designpath = designpath, u = ul, bcoeff = "not a list")
    )
  })

  test_that("B coefficients in the utility functions dont match those in the bcoeff list", {
    expect_error(sim_all(nosim = nosim, resps=resps, destype = destype,
                         designpath = designpath, u = ul, bcoeff = list(bWRONG = 0.00)))
  })

  test_that("Utility functions are valid", {
    expect_no_error(eval(ul$u1$v1))
    expect_no_error(eval(ul$u1$v2))
  })

  test_that("Design path must be a valid directory", {
    # Test case: designpath is not a character string
    expect_error(sim_all(nosim = nosim, resps = resps, destype = destype, designpath = 123, u = ul, bcoeff = bcoeff))

    # Test case: designpath does not exist
    expect_error(sim_all(nosim = nosim, resps = resps, destype = destype, designpath = '/nonexistent/path', u = ul, bcoeff = bcoeff))

    # Test case: designpath is not a directory
    expect_error(sim_all(nosim = nosim, resps = resps, destype = destype, designpath = 'path/to/a/file.txt', u = ul, bcoeff = bcoeff))
  })

  test_that("Resps must be an integer", {
    # Test case: resps is missing
    expect_error(sim_all(nosim = nosim, destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff))

    # Test case: resps is not an integer
    expect_error(sim_all(nosim = nosim, resps = "abc", destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff))

    # Test case: resps is a numeric but not an integer
    expect_error(sim_all(nosim = nosim, resps = 1.5, destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff))

  })

  test_that("Function exists in simulateDCE", {
    expect_true("sim_all" %in% ls("package:simulateDCE"))
  })

  test_that("Simulation results are reasonable", {

    result1 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul, bcoeff = bcoeff, decisiongroups = decisiongroups)

    # obtain the names of the design files (without extensions)
    designs <- tools::file_path_sans_ext(list.files(designpath, full.names = FALSE))

    ## Now access the summary data. this is tricky because a different table is made for each design
    ## to address this, loop through all designs and run tests on each design
    for (design in designs) {
      # Access the summary data frame for the current design
      summaryTable <- result1[[design]][["summary"]]

      ##nested loop looks at each row starting with est_ (estimated bcoeffs)
      for (row_name in rownames(summaryTable)) {
        if (startsWith(row_name, "est_")) {

          betaCoeff <- sub("^est_", "", row_name) #simpkly strip prefix
          meanBeta <- summaryTable[row_name, 'mean']
          inputBeta <- as.integer(bcoeff[betaCoeff]) # access beta coefficient list by specific coefficient name

          # Perform tests for rows starting with "est_"
          expect_true(betaCoeff %in% names(bcoeff),
                      sprintf("Variable est_%s does not exist in summary data frame", variable))


          expect_gt(meanBeta, inputBeta - 1)
          expect_lt(meanBeta, inputBeta + 1)
        }
      }
    }


  })
}

###################
## FROM RBOOK #####
###################

designpath<- system.file("extdata","Rbook" ,package = "simulateDCE")

#notes <- "This design consists of different heuristics. One group did not attend the methan attribute, another group only decided based on the payment"

notes <- "No Heuristics"

resps =40  # number of respondents
nosim=2 # number of simulations to run (about 500 is minimum)

#betacoefficients should not include "-"

bcoeff <-list(bsq=0.00,
              bredkite=-0.05,
              bdistance=0.50,
              bcost=-0.05,
              bfarm2=0.25,
              bfarm3=0.50,
              bheight2=0.25,
              bheight3=0.50)

destype <- "spdesign"


#place your utility functions here
ul<- list(u1= list(
  v1 =V.1 ~  bsq * alt1.sq,
  v2 =V.2 ~  bfarm2 * alt2.farm2 + bfarm3 * alt2.farm3 + bheight2 * alt2.height2 + bheight3 * alt2.height3 +  bredkite * alt2.redkite + bdistance * alt2.distance + bcost * alt2.cost,
  v3 =V.3 ~  bfarm2 * alt3.farm2 + bfarm3 * alt3.farm3 + bheight2 * alt3.height2 + bheight3 * alt3.height3 +  bredkite * alt3.redkite + bdistance * alt3.distance + bcost * alt3.cost
)
)

comprehensive_design_test(nosim=nosim, resps=resps, destype=destype, designpath=designpath, ul = ul, bcoeff = bcoeff)

###############################
#### From feedadditives #######
###############################

designpath<- system.file("extdata","feedadditives" ,package = "simulateDCE")

#notes <- "This design consists of different heuristics. One group did not attend the methan attribute, another group only decided based on the payment"

notes <- "Three heuristics"

resps =30  # number of respondents
nosim=2 # number of simulations to run (about 500 is minimum)
destype = "ngene"

#betacoefficients should not include "-"
bcoeff = list(
  basc = 0.2,
  bcow = 0.3,
  badv = 0.3,
  bvet = 0.3,
  bfar = 0.3,
  bmet = 0.3,
  bbon = 0.3,
  bbon2 = 1.9,
  basc2 = 2)

dgFeed=c(0,0.3,0.6,0.8,1)

#place your utility functions here
ul<- list(u1= list(
  v1 =V.1 ~  bcow*alt1.cow + badv * alt1.adv + bvet * alt1.vet + bfar * alt1.far + bmet*alt1.met + bbon * alt1.bon,
  v2 =V.2 ~  bcow*alt2.cow + badv * alt2.adv + bvet * alt2.vet + bfar * alt2.far + bmet*alt2.met + bbon * alt2.bon,
  v3 =V.3 ~ basc)
  ,
  u2 = list(
    v1 =V.1 ~  bcow*alt1.cow + badv * alt1.adv + bvet * alt1.vet + bfar * alt1.far + bbon * alt1.bon,
    v2 =V.2 ~  bcow*alt2.cow + badv * alt2.adv + bvet * alt2.vet + bfar * alt2.far + bbon * alt2.bon,
    v3 =V.3 ~ basc),
  u3 = list(
    v1 =V.1 ~  bbon2 * alt1.bon,
    v2 =V.2 ~  bbon2 * alt2.bon,
    v3 =V.3 ~ basc),

  u4 = list(v1 =V.1 ~ basc2 + bcow*alt1.cow + badv * alt1.adv + bvet * alt1.vet + bfar * alt1.far + bmet*alt1.met + bbon * alt1.bon,
            v2 =V.2 ~  bcow*alt2.cow + badv * alt2.adv + bvet * alt2.vet + bfar * alt2.far + bmet*alt2.met + bbon * alt2.bon,
            v3 =V.3 ~ basc)
)

## comprehensive_design_test(nosim=nosim, resps=resps, destype=destype, designpath=designpath, ul = ul, bcoeff = bcoeff, decisiongroups = dgFeed)