# CREATE_ALL_WEEKLY_MOSAICS.R
# ===========================
# Generate weekly mosaics for all available weeks in the merged_final_tif dataset
# This script identifies all unique weeks from the TIF files and creates mosaics
# for weeks that don't already have mosaics.

suppressPackageStartupMessages({
  library(terra)
  library(sf)
  library(dplyr)
  library(lubridate)
  library(here)
})

# Set project directory
project_dir <- "esa"
assign("project_dir", project_dir, envir = .GlobalEnv)

# Source required files
cat("Loading project configuration...\n")
source(here("r_app", "parameters_project.R"))
source(here("r_app", "mosaic_creation_utils.R"))

# Get all TIF files from merged_final_tif
merged_final_dir <- here("laravel_app/storage/app", project_dir, "merged_final_tif")
tif_files <- list.files(merged_final_dir, pattern = "\\.tif$", full.names = FALSE)

cat("Found", length(tif_files), "TIF files\n")

# Extract dates from filenames
dates <- as.Date(gsub("\\.tif$", "", tif_files))
cat("Date range:", as.character(min(dates)), "to", as.character(max(dates)), "\n")

# Create a data frame with week and year for each date
weeks_df <- data.frame(
  date = dates,
  week = isoweek(dates),
  year = isoyear(dates)
) %>%
  # Get unique weeks
  distinct(week, year) %>%
  arrange(year, week) %>%
  # Create a representative date for each week (middle of the week)
  mutate(
    # Calculate the Monday of each ISO week
    week_start = as.Date(paste0(year, "-01-01")) + weeks((week - 1)),
    # Adjust to ensure it's actually the correct week
    week_start = week_start - wday(week_start, week_start = 1) + 1,
    # Use Wednesday as the representative date (middle of week)
    representative_date = week_start + 2
  )

cat("Total unique weeks:", nrow(weeks_df), "\n")

# Check which mosaics already exist
weekly_mosaic_dir <- here("laravel_app/storage/app", project_dir, "weekly_mosaic")
existing_mosaics <- list.files(weekly_mosaic_dir, pattern = "^week_.*\\.tif$", full.names = FALSE)
existing_weeks <- gsub("^week_|.tif$", "", existing_mosaics) %>%
  strsplit("_") %>%
  lapply(function(x) data.frame(week = as.integer(x[1]), year = as.integer(x[2]))) %>%
  bind_rows()

cat("Existing mosaics:", nrow(existing_weeks), "\n")

# Find missing weeks
weeks_df <- weeks_df %>%
  anti_join(existing_weeks, by = c("week", "year")) %>%
  arrange(year, week)

cat("Missing mosaics:", nrow(weeks_df), "\n")
cat("\n")

if (nrow(weeks_df) == 0) {
  cat("All mosaics already exist!\n")
  quit(save = "no", status = 0)
}

# Ask for confirmation
cat("This will create", nrow(weeks_df), "weekly mosaics.\n")
cat("Estimated time: ~", round(nrow(weeks_df) * 30 / 60, 1), "minutes (assuming 30 seconds per mosaic)\n")
cat("\nProcessing will begin in 5 seconds... (Ctrl+C to cancel)\n")
Sys.sleep(5)

# Create mosaics for each missing week
cat("\n=== Starting mosaic creation ===\n\n")
success_count <- 0
error_count <- 0
error_weeks <- list()

for (i in 1:nrow(weeks_df)) {
  week_info <- weeks_df[i, ]
  
  cat(sprintf("[%d/%d] Creating mosaic for week %02d of %d...", 
              i, nrow(weeks_df), week_info$week, week_info$year))
  
  tryCatch({
    # Use the representative date (Wednesday of the week) with 7-day offset
    end_date <- week_info$representative_date
    offset <- 7  # Look back 7 days to cover the whole week
    
    # Generate date range
    dates <- date_list(end_date, offset)
    
    # Create output filename
    file_name_tif <- sprintf("week_%02d_%d.tif", week_info$week, week_info$year)
    
    # Create the mosaic
    output_file <- create_weekly_mosaic(
      dates = dates,
      field_boundaries = field_boundaries,
      daily_vrt_dir = daily_vrt,
      merged_final_dir = merged_final_dir,
      output_dir = weekly_mosaic_dir,
      file_name_tif = file_name_tif,
      create_plots = FALSE  # Disable plots for batch processing
    )
    
    if (file.exists(output_file)) {
      cat(" ✓\n")
      success_count <- success_count + 1
    } else {
      cat(" ✗ (file not created)\n")
      error_count <- error_count + 1
      error_weeks[[length(error_weeks) + 1]] <- week_info
    }
    
  }, error = function(e) {
    cat(" ✗\n")
    cat("  Error:", e$message, "\n")
    error_count <- error_count + 1
    error_weeks[[length(error_weeks) + 1]] <- week_info
  })
  
  # Progress update every 10 mosaics
  if (i %% 10 == 0) {
    cat(sprintf("\nProgress: %d/%d completed (%.1f%%) | Success: %d | Errors: %d\n\n",
                i, nrow(weeks_df), (i/nrow(weeks_df))*100, success_count, error_count))
  }
}

# Final summary
cat("\n=== SUMMARY ===\n")
cat("Total weeks processed:", nrow(weeks_df), "\n")
cat("Successful:", success_count, "\n")
cat("Errors:", error_count, "\n")

if (error_count > 0) {
  cat("\nWeeks with errors:\n")
  error_df <- bind_rows(error_weeks)
  print(error_df)
}

cat("\nDone!\n")