# Search packages for host system instead of packages for target system
# in case of cross compilation thess macro should be defined by toolchain file
if(NOT COMMAND find_host_package)
  macro(find_host_package)
    find_package(${ARGN})
  endmacro()
endif()
if(NOT COMMAND find_host_program)
  macro(find_host_program)
    find_program(${ARGN})
  endmacro()
endif()


# Provides an option that the user can optionally select.
# Can accept condition to control when option is available for user.
# Usage:
#   option(<option_variable> "help string describing the option" <initial value or boolean expression> [IF <condition>])
macro(OCV_OPTION variable description value)
  set(__value ${value})
  set(__condition "")
  set(__varname "__value")
  foreach(arg ${ARGN})
    if(arg STREQUAL "IF" OR arg STREQUAL "if")
      set(__varname "__condition")
    else()
      list(APPEND ${__varname} ${arg})
    endif()
  endforeach()
  unset(__varname)
  if("${__condition}" STREQUAL "")
    set(__condition 2 GREATER 1)
  endif()

  if(${__condition})
    if("${__value}" MATCHES ";")
      if(${__value})
        option(${variable} "${description}" ON)
      else()
        option(${variable} "${description}" OFF)
      endif()
    elseif(DEFINED ${__value})
      if(${__value})
        option(${variable} "${description}" ON)
      else()
        option(${variable} "${description}" OFF)
      endif()
    else()
      option(${variable} "${description}" ${__value})
    endif()
  else()
    unset(${variable} CACHE)
  endif()
  unset(__condition)
  unset(__value)
endmacro()


# Macros that checks if module have been installed.
# After it adds module to build and define
# constants passed as second arg
macro(CHECK_MODULE module_name define)
  set(${define} 0)
  if(PKG_CONFIG_FOUND)
    set(ALIAS               ALIASOF_${module_name})
    set(ALIAS_FOUND                 ${ALIAS}_FOUND)
    set(ALIAS_INCLUDE_DIRS   ${ALIAS}_INCLUDE_DIRS)
    set(ALIAS_LIBRARY_DIRS   ${ALIAS}_LIBRARY_DIRS)
    set(ALIAS_LIBRARIES         ${ALIAS}_LIBRARIES)

    PKG_CHECK_MODULES(${ALIAS} ${module_name})

    if(${ALIAS_FOUND})
      set(${define} 1)
      foreach(P "${ALIAS_INCLUDE_DIRS}")
        if(${P})
          list(APPEND HIGHGUI_INCLUDE_DIRS ${${P}})
        endif()
      endforeach()

      foreach(P "${ALIAS_LIBRARY_DIRS}")
        if(${P})
          list(APPEND HIGHGUI_LIBRARY_DIRS ${${P}})
        endif()
      endforeach()

      list(APPEND HIGHGUI_LIBRARIES ${${ALIAS_LIBRARIES}})
    endif()
  endif()
endmacro()


# Status report function.
# Automatically align right column and selects text based on condition.
# Usage:
#   status(<text>)
#   status(<heading> <value1> [<value2> ...])
#   status(<heading> <condition> THEN <text for TRUE> ELSE <text for FALSE> )
function(status text)
  set(status_cond)
  set(status_then)
  set(status_else)

  set(status_current_name "cond")
  foreach(arg ${ARGN})
    if(arg STREQUAL "THEN")
      set(status_current_name "then")
    elseif(arg STREQUAL "ELSE")
      set(status_current_name "else")
    else()
      list(APPEND status_${status_current_name} ${arg})
    endif()
  endforeach()

  if(DEFINED status_cond)
    set(status_placeholder_length 32)
    string(RANDOM LENGTH ${status_placeholder_length} ALPHABET " " status_placeholder)
    string(LENGTH "${text}" status_text_length)
    if(status_text_length LESS status_placeholder_length)
      string(SUBSTRING "${text}${status_placeholder}" 0 ${status_placeholder_length} status_text)
    elseif(DEFINED status_then OR DEFINED status_else)
      message(STATUS "${text}")
      set(status_text "${status_placeholder}")
    else()
      set(status_text "${text}")
    endif()

    if(DEFINED status_then OR DEFINED status_else)
      if(${status_cond})
        string(REPLACE ";" " " status_then "${status_then}")
        message(STATUS "${status_text}" "${status_then}")
      else()
        string(REPLACE ";" " " status_else "${status_else}")
        message(STATUS "${status_text}" "${status_else}")
      endif()
    else()
      string(REPLACE ";" " " status_cond "${status_cond}")
      message(STATUS "${status_text}" "${status_cond}")
    endif()
  else()
    message(STATUS "${text}")
  endif()
endfunction()


# splits cmake libraries list of format "general;item1;debug;item2;release;item3" to two lists
macro(ocv_split_libs_list lst lstdbg lstopt)
  set(${lstdbg} "")
  set(${lstopt} "")
  set(perv_keyword "")
  foreach(word ${${lst}})
    if(word STREQUAL "debug" OR word STREQUAL "optimized")
      set(perv_keyword ${word})
    elseif(word STREQUAL "general")
      set(perv_keyword "")
    elseif(perv_keyword STREQUAL "debug")
      list(APPEND ${lstdbg} "${word}")
      set(perv_keyword "")
    elseif(perv_keyword STREQUAL "optimized")
      list(APPEND ${lstopt} "${word}")
      set(perv_keyword "")
    else()
      list(APPEND ${lstdbg} "${word}")
      list(APPEND ${lstopt} "${word}")
      set(perv_keyword "")
    endif()
  endforeach()
endmacro()


# remove all matching elements from the list
macro(ocv_list_filterout lst regex)
  foreach(item ${${lst}})
    if(item MATCHES "${regex}")
      list(REMOVE_ITEM ${lst} "${item}")
    endif()
  endforeach()
endmacro()


# stable & safe duplicates removal macro
macro(ocv_list_unique __lst)
  if(${__lst})
    list(REMOVE_DUPLICATES ${__lst})
  endif()
endmacro()


# safe list reversal macro
macro(ocv_list_reverse __lst)
  if(${__lst})
    list(REVERSE ${__lst})
  endif()
endmacro()


# safe list sorting macro
macro(ocv_list_sort __lst)
  if(${__lst})
    list(SORT ${__lst})
  endif()
endmacro()


# simple regex escaping routine (does not cover all cases!!!)
macro(ocv_regex_escape var regex)
  string(REGEX REPLACE "([+.*^$])" "\\\\1" ${var} "${regex}")
endmacro()